(19)
(11)EP 3 462 640 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
26.02.2020 Bulletin 2020/09

(21)Application number: 18201145.2

(22)Date of filing:  13.11.2009
(51)International Patent Classification (IPC): 
H04B 7/26(2006.01)
H04W 28/18(2009.01)

(54)

ASYMMETRIC TDD IN FLEXIBLE USE SPECTRUM

ASYMMETRISCHES TDD IN EINEM FLEXIBLEN NUTZUNGSSPEKTRUM

TDD ASYMÉTRIQUE DANS UN SPECTRE À UTILISATION FLEXIBLE


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

(30)Priority: 14.11.2008 US 270946

(43)Date of publication of application:
03.04.2019 Bulletin 2019/14

(62)Application number of the earlier application in accordance with Art. 76 EPC:
18163866.9 / 3361652
09764120.3 / 2359499

(73)Proprietor: DBSD Satellite Services G.P.
Reston, Virginia 20190 (US)

(72)Inventors:
  • SOROND, Mariam
    Reston, Virginia 20194 (US)
  • COREA, Peter
    Alexandria, Virginia 22311 (US)
  • HYSLOP, Doug
    Vienna, Virginia 22181 (US)
  • PETERS, Tom
    McLean, Virginia 22101 (US)

(74)Representative: LKGLOBAL Lorenz & Kopf PartG mbB Patentanwälte 
Brienner Straße 11
80333 München
80333 München (DE)


(56)References cited: : 
US-A1- 2004 165 547
US-A1- 2006 126 546
US-A1- 2006 077 931
US-A1- 2007 286 156
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    CROSS-REFERENCE TO RELATED APPLICATION



    [0001] This application is a continuation of and claims the benefit of US 2010/0124183 A1.

    BACKGROUND



    [0002] The invention relates generally to wireless communication systems and more particularly to a communication method that uses time division duplexing.

    [0003] In addition to traditional voice services, next generation wireless communication systems have to support various different types of multimedia services, including broadcasts, video conferencing, and interactive applications, for example. Many of these multimedia services may require flexibility in their use of spectrum capacity to operate effectively. The typical spectrum management approach is to assign frequencies to a particular use. This approach, however, has become somewhat limited in view of the complexity and overlap between the operations of next generation services and applications. One regulatory solution has been the introduction of flexible-use spectrum in which users of assigned portions of spectrum have more freedom to decide which technologies and services to deploy. In this regard, flexible-use spectrum can allow spectrum users to make timely commercial choices and can let market forces determine which competing technologies and services will be offered in a particular frequency band. Such approach can result in a more effective use of spectrum than that which occurs by imposing a technology or a service by regulation. As a result of these efforts to open up the spectrum, new user-based communication techniques are being considered that address aspects that are particular to next generation services and applications. For example, communication methods that include duplexing techniques or schemes that incorporate the inherent asymmetry in data flow that is characteristic of many multimedia services are being considered for next generation wireless communication systems.

    [0004] Duplexing techniques include time division duplexing (TDD), frequency division duplexing (FDD), and/or hybrid duplexing, the latter of which includes aspects of both TDD and FDD schemes. In TDD, bidirectional communication or data flow is implemented through a communication link by separating the communication time within a given frequency band associated with the communication link into alternating transmission time slots and reception time slots. A time guard is used between time slots to reduce or minimize the likelihood of interference. In this scheme, a satellite or a base station, for example, can allocate a number of transmission time slots different from a number of reception time slots to a mobile device within a given time interval to produce asymmetric data communication. As the area of coverage provided by the satellite or the base station increases significantly, the guard time between time slots may be increased to compensate for delays that result from a longer signal round-trip between the satellite or base station and the mobile device. The increased delay can reduce the communication efficiency of the TDD scheme. In many instances, however, the time guard is sufficiently small even when large areas of coverage are concerned such that the TDD scheme efficiency remains adequate for many services or applications.

    [0005] In FDD, bidirectional communication or data flow is implemented through a communication link by partitioning a given frequency band associated with the communication link into separate transmission and reception frequency bands that operate concurrently. Because the transmission and reception bands are separate from each other to reduce the likelihood of interference, no time delays occur associated with the transmission or reception of signals (i.e., no round-trip delays). Although the FDD scheme may be suitable for large areas of coverage because time delays do not play a significant role, the fixed and balanced nature of the transmission and reception frequency bands limit the flexibility that is necessary for asymmetric data communication in next generation wireless communication services. Some FDD schemes achieve asymmetry by using an auxiliary frequency band separate from the paired transmission and reception frequency bands to provide additional capacity in one direction of the data flow. This approach, however, requires the communication system to include additional hardware and/or software to handle the separate frequency band through which asymmetry is achieved. US 2004/165547 A1 describes that the amount of interference to communications in Time Division Duplexing (TDD) mode between a TDD mobile and a TDD base station from a mobile operating in Frequency Division Duplexing (FDD) mode that is located near to the TTD base station can be reduced by changing at least the frequency channel allocated to a particular TDD communications channel, and also by changing the timeslot allocated to that particular TDD communications channel. Thus, instead of allocating particular frequency channels to particular operators for TDD communication, the frequency channels used by any particular operator for TDD communication can change from frame to frame. The timeslots within a frame on a frequency channel may stay the same or may also change. Thus, any particular communications channel (6,8) will not remain on the same frequency channel, nor, possibly, on the same timeslot within a frame, from one frame to the next, so that no one TDD channel will have continuous interference from an FDD channel, but all the TDD communications channels will have the interference shared between them.

    [0006] US 2007/0286156 A1 refers to a wireless system and method includes a FDD system configured to provide at least a first FDD channel operating within a first frequency band. A TDD system is configured to provide at least a first TDD channel operating within a second frequency band. The first frequency band and the second frequency band are separated by a third frequency band, and a half-duplex frequency division duplex (H-FDD) system is configured to provide at least a first H-FDD channel operating within the third frequency band. A transmission of the first H-FDD channel may be synchronized with one of an uplink transmission and a downlink transmission of the first TDD channel.

    [0007] US 2006/0126546 A1 refers to a wireless communication system in an overlay network where systems using different frequency bands coexist. The wireless communication system includes at least one first duplexing system utilizing a first duplexing technique through a first frequency band, and at least one second duplexing system utilizing a second frequency band and a part of the first frequency band. The second duplexing system overlaps with the first duplexing system in coverage.

    [0008] US 2006/077931 A1 describes an enhanced hybrid duplexing technology (EDHT)-based communication method including dividing a cell prescribed by a transmission power of the base station into at least two logical areas, dividing the system frequency band into at least two subbands, and communicating in different duplexing modes using at least one of the subbands according to a position of the terminal within the cell. According to the method, a flexible resource management is possible according to the communication environment by dividing an entire system band into at least two subbands, differentiating the bandwidths of the subbands and the duplexing techniques, and selecting and allocating the resources of the subbands according to the position of the terminal within the cell.

    [0009] Thus, a need exists for new methods for asymmetric communication in wireless communication systems.

    SUMMARY



    [0010] The invention is defined by the appended claims.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0011] 

    FIG. 1 is a schematic representation of a wireless communication system, according to an example.

    FIG. 2 is a schematic representation of coexisting mobile devices, according to examples.

    FIG. 3 is a diagram illustrating an asymmetric time division duplexing (TDD) scheme in AWS-3 flexible use spectrum, according to an example.

    FIG. 4 is a diagram illustrating aspects of an asymmetric TDD communication scheme for use in the AWS-3 portion of the wireless spectrum, according to an example.

    FIGS. 5A-5B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent frequency division duplexing (FDD) schemes, according to examples.

    FIGS. 6A-6B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD schemes, according to examples.

    FIGS. 7A-7B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD and synchronous TDD schemes, with FIG. 7A being an example and FIG. 7B illustrating an embodiment of the invention.

    FIGS. 7C-7D are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD and synchronous TDD schemes, with FIG. 7C being an example and FIG. 7D illustrating an embodiment of the invention.

    FIGS. 8A-8B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent synchronous TDD and asynchronous TDD schemes, according to examples.

    FIGS. 9A-9B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent synchronous TDD and temporally-asymmetric TDD schemes, according to examples.

    FIGS. 10A-10B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent temporally-asymmetric TDD schemes, according to examples.

    FIGS. 11A-11B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent temporally-asymmetric TDD schemes, according to examples.

    FIGS. 12A-12B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD and broadcast schemes, according to examples.

    FIGS. 13-15 are flow charts illustrating a method for a TDD scheme, according to examples.


    DETAILED DESCRIPTION



    [0012] The devices and methods described herein are generally related to wireless communication systems. For example, the devices and methods are suitable for use in cellular (terrestrial) communication systems, satellite communication systems, and/or hybrid satellite and terrestrial (satellite/terrestrial) communication systems, such as a Mobile Satellite Services (MSS) system with an Ancillary Terrestrial Component (ATC). An example of such a hybrid satellite/terrestrial communication system is described in U.S. patent application US 2008/0268838 A1 to Zufall et, al. An MSS MSS/ATC system can use one or more satellites to support a wide geographic coverage of mobile satellite interactive (i.e., bidirectional) services. For example, a portion of the 2 GHz spectrum allocated for MSS satellite communications can be used to provide effective service coverage to rural and remote areas. Along with the MSS network, the land-based ATC network can facilitate service penetration in urban and suburban areas through effective satellite and terrestrial frequency reuse.

    [0013] In one or more embodiments, a method associated with terrestrial, satellite, and/or hybrid satellite/terrestrial wireless communication systems includes receiving and transmitting signals over an asymmetric time division duplex (TDD) communication path. Signals are received over the asymmetric TDD communication path via a first portion of a first frequency band. The first frequency band is adjacent to a second frequency band and to a third frequency band. The first frequency band is different from the second frequency band and from the third frequency band. The first frequency band, the second frequency band, and the third frequency band can be mutually exclusive. A first frequency division duplex (FDD) communication path can be operated in the second frequency band. A second FDD communication path can be operated in the third frequency band. Signals are transmitted over the TDD communication path via a second portion of the first frequency band that is different from the first portion of the first frequency band.

    [0014] It is noted that, as used in this written description and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, the term "a frequency" is intended to mean a single frequency or a combination of frequencies. Similarly, the term "a time slot" is intended to mean, for example, a single time slot or more than one time slot.

    [0015] FIG. 1 is a schematic representation of a wireless communication system 100, according to an examples. The wireless communication system 100 is configured to provide next generation wireless communication services and applications, including interactive services, for example. The wireless communication system 100 includes a terrestrial antenna 140 and a mobile device 110. In some examples, the wireless communication system 100 can include at least one of a satellite 130 and a broadcast antenna 120. In some examples, the wireless communication system 100 can include multiple terrestrial antennas, multiple satellites, and/or multiple broadcast antennas, for example.

    [0016] The terrestrial antenna 140 is configured to communicate multicast and/or interactive data with the mobile device 110 via a terrestrial communication path, channel, or link, for example, which includes a downlink portion 142 and/or an uplink portion 144. In this example, the downlink portion 142 refers to the portion of the terrestrial communication path in which data or information flows from the terrestrial antenna 140 to the mobile device 110. The terrestrial antenna 140 is thus configured to send, transmit, or transfer data to the mobile device 110 via the downlink portion 142 of the terrestrial communication path, while the mobile device 110 is configured to receive data at downlink portion 142. The uplink portion 144 refers to a portion of the terrestrial communication path in which data or information flows from the mobile device 110 to the terrestrial antenna 140. The mobile device 110 is thus configured to send, transmit, or transfer data to the terrestrial antenna 140 via the uplink portion 144 of the terrestrial communication path, while the terrestrial antenna 140 is configured to receive at uplink portion 144. The terrestrial antenna 140 can be associated with a wireless base station used, for example, in cellular or like communication systems. In some examples, the downlink portion 142 of the terrestrial communication path and the uplink portion 144 of the terrestrial communication path operate over the same frequency band. In other examples, the downlink portion 142 of the terrestrial communication path operates over a first frequency band and the uplink portion 144 of the terrestrial communication path operates over a second frequency band different from the first frequency band.

    [0017] The terrestrial antenna 140 is configured to communicate with the mobile device 110 via the terrestrial communication path, for example, by using a duplexing scheme such as a TDD scheme, an FDD scheme, and/or a hybrid TDD/FDD scheme. The terrestrial antenna 140 is thus configured to establish and/or operate an asymmetric TDD communication scheme with the mobile device 110 via the terrestrial communication path. An asymmetric TDD communication scheme refers to a TDD communication path, channel, or link, for example, between the terrestrial antenna 140 and the mobile device 110 in which the amount of data flowing in one direction (uplink or downlink) is larger than the amount of data flowing in the opposite direction. For example, in interactive multimedia applications, the amount of data (e.g., video) flowing from the terrestrial antenna 140 to the mobile device 110 is larger than the amount of data (e.g., user selections) flowing from the mobile device 110 to the terrestrial antenna 140. The amount of data flowing in a given direction can be based on a spectrum bandwidth associated with that direction and/or a time interval associated with the flow of data in that direction. An asymmetric TDD communication scheme may provide the asymmetry that is desirable in many next generation services and applications without the need for an auxiliary frequency band to increase capacity in one direction or another.

    [0018] The broadcast antenna 120 is configured to communicate with the mobile device 110 via a broadcast 122. In this example, data flows from the broadcast antenna 120 to the mobile device 110. In one example, the broadcast antenna 120 can be a directional antenna and can be configured such that the broadcast 122 occurs in a particular direction. In another example, the broadcast antenna 120 can be an omni-directional antenna and can be configured such that the broadcast 122 occurs uniformly in every direction.

    [0019] The satellite 130 is configured to communicate multicast and/or interactive data with the mobile device 110 via a satellite communication path, channel, or link, for example, which includes a downlink portion 132 and/or an uplink portion 134. In this example, the downlink portion 132 refers to the portion of the satellite communication path in which data or information flows from the satellite 130 to the mobile device 110. The satellite 130 is thus configured to send, transmit, or transfer data (e.g., video content) to the mobile device 110 via the downlink portion 132 of the satellite communication path, while the mobile device 110 is configured to receive data from the satellite 130 via that downlink portion 132. The uplink portion 134 refers to a portion of the satellite communication path in which data or information flows from the mobile device 110 to the satellite 130. The mobile device 110 is thus configured to send, transmit, or transfer data (e.g., interactive data) to the satellite 130 via the uplink portion 134 of the satellite communication path, while the satellite 130 is configured to receive data from the mobile device 110 via that uplink portion 134. In some examples, the downlink portion 132 of the satellite communication path and the upstream portion 134 of the satellite communication path operate over the same frequency band. In other examples, the downlink portion 132 of the satellite communication path operates over a first frequency band and the upstream portion 134 of the satellite communication path operates over a second frequency band different from the first frequency band.

    [0020] The satellite 130 is configured to communicate with the mobile device 110 via the satellite communication path, for example, by using a duplexing scheme such as a TDD scheme, an FDD scheme, and/or a hybrid TDD/FDD scheme. The satellite 130 is configured to establish and/or operate an asymmetric TDD communication scheme with the mobile device 110 via the satellite communication path. For example, in interactive travel assistance applications, the amount of data (e.g., navigation data) flowing from the satellite 130 to the mobile device 110 is larger than the amount of data (e.g., user queries) flowing from the mobile device 110 to the satellite 130. The amount of data flowing in a given direction can be based on a spectrum bandwidth associated with that direction and/or a time interval associated with that direction.

    [0021] In some examples, the satellite 130 and the terrestrial antenna 140 can be used in a hybrid satellite/terrestrial communication system to communicate with the mobile device 110. For example, the satellite 130 can be configured to communicate with the terrestrial antenna 140 such that data can flow from the satellite 130 to the mobile device 110 via the terrestrial antenna 140. In this example, the satellite 130 can be configured to send data to the terrestrial antenna 140 via a downlink portion of a given satellite communication path (not shown) with the terrestrial antenna 140. The terrestrial antenna 140 can be configured to send the data received from the satellite 130 to the mobile device 110 via the downlink portion 142 of the terrestrial communication path. In another example, the terrestrial antenna 140 can be configured to communicate with the satellite 130 via a network (not shown) and/or a ground station (not shown).

    [0022] The mobile device 110 can include a handheld device, a laptop, and/or an in-vehicle system, for example. The mobile device 110 is configured to communicate with the satellite 130 and/or the terrestrial antenna 140. For example, the mobile device 110 can be configured to communicate with the satellite 130 via an asymmetric TDD communication scheme (e.g., TDD downlink and TDD uplink) over a satellite communication path. In another example, the mobile device 110 can be configured to communicate with the terrestrial antenna 140 via an asymmetric TDD communication scheme (e.g., TDD downlink and TDD uplink) over a terrestrial communication path. The mobile device 110 can also be configured to receive broadcast data from the broadcast antenna 120. The functionality of the mobile device 110 can be software-based (e.g., set of instructions executable at a processor, software code) and/or hardware-based (e.g., circuit system, processor, application-specific integrated circuit (ASIC), field programmable gate array (FPGA)). The mobile device 110 can include a processor and a related processor-readable medium having instructions or computer code thereon for performing various processor-implemented operations. Such processors can be implemented as hardware modules such as embedded microprocessors, microprocessors as part of a computer system, Application-Specific Integrated Circuits ("ASICs"), and Programmable Logic Devices ("PLDs"). Such processors can also be implemented as one or more software modules in programming languages as Java, C++, C, assembly, a hardware description language, or any other suitable programming language.

    [0023] A processor according to some examples of the mobile device 110 includes media and computer code (also can be referred to as code) specially designed and constructed for the specific purpose or purposes. Examples of processor-readable media include, but are not limited to: magnetic storage media such as hard disks, floppy disks, and magnetic tape; optical storage media such as Compact Disc/Digital Video Discs ("CD/DVDs"), Compact Disc-Read Only Memories ("CD-ROMs"), and holographic devices; magneto-optical storage media such as optical disks, and read-only memory ("ROM") and random-access memory ("RAM") devices. Examples of computer code include, but are not limited to, micro-code or micro-instructions, machine instructions, such as produced by a compiler, and files containing higher-level instructions that are executed by a computer using an interpreter. For example, an example of the mobile device 110 may be implemented using Java, C++, or other object-oriented programming language and development tools. Additional examples of computer code include, but are not limited to, control signals, encrypted code, and compressed code.

    [0024] In some examples, at least a portion of the wireless communication system 100 can be pre-configured to support an asymmetric TDD communication scheme. In other examples, at least a portion of the wireless communication system 100 can be dynamically configured (e.g., after deployment) to support an asymmetric TDD communication scheme.

    [0025] FIG. 2 is a schematic representation showing mobile devices 210, 220, and 230 operating in an area 200, according to examples. The mobile device 220 is configured to communicate with a given wireless communication system (not shown), such as the wireless communication system 100 described above with respect to FIG. 1. The mobile device 220 can communicate with that wireless communication system via an asymmetric TDD communication scheme. For example, the mobile device 220 can communicate via an uplink portion 224 and a downlink portion 222 of an asymmetric TDD communication scheme associated with a particular frequency band (frequency band 1).

    [0026] The mobile device 210 and the mobile device 230 are each configured to communicate with a wireless communication system (not shown) via a communication path that includes one of multiple communication methods such as an FDD communication scheme, a TDD communication scheme synchronous with the asymmetric TDD communication scheme associated with the mobile device 220, a TDD communication scheme asynchronous with the asymmetric TDD communication scheme associated with the mobile device 220, a temporally-asymmetric TDD communication scheme, or a broadcast, for example. In some examples, the mobile device 210 can communicate with its associated wireless communication system via a communication path having an uplink portion 214 and a downlink portion 212. Each of the uplink portion 214 and the downlink portion 212 of the communication path is associated with a frequency band 2. Similarly, the mobile device 230 can communicate with its associated wireless communication system via a communication path having an uplink portion 234 and a downlink portion 232. Each of the uplink portion 234 and downlink portion 2232 is associated with a frequency band 3. In some examples, the frequency band 2 and/or the frequency band 3 can include multiple frequency bands or frequency subbands.

    [0027] The frequency bands 1, 2, and 3 can be adjacent (i.e., adjoining or neighboring) frequency bands. For example, frequency band 1 can be adjacent to frequency band 2 and adjacent to frequency band 3. The frequency bands 1, 2, and 3 can be mutually exclusive frequency bands, for example. In some examples, the frequency band 1 can be associated with a flexible-use spectrum, for example.

    [0028] The mobile devices 220 and 210 are configured to coexist in the area 200 such that minimal (if any) interference occurs between the asymmetric TDD communication scheme being used by the mobile device 220 (and associated with frequency band 1) and the communication method being used by the mobile device 210 (and associated with frequency band 2). Similarly, the mobile devices 220 and 230 are configured to coexist in the area 200 such that minimal (if any) interference occurs between the asymmetric TDD communication scheme being used by the mobile device 220 (and associated with frequency band 1) and the communication method being used by the mobile device 230 (and associated with frequency band 3). The size of the area 200 may be associated with the minimum distance between the mobile device 220 and the mobile device 210, and/or the minimum distance between the mobile device 220 and the mobile device 230 such that the mobile devices 210, 220, and/or 230 can effectively operate (i.e., coexist) without interfering with each other.

    [0029] FIG. 3 is a diagram illustrating an asymmetric TDD scheme in an advanced wireless services (AWS) spectrum, according to an example. The wireless spectrum 300 is a portion of the radio frequency spectrum that includes a portion 310 (AWS-1 F Block), a portion 320 (AWS-3), a portion 330 (J Block), a portion 340 (MSS-1), and a portion 350 (MSS-2). The AWS-1 and AWS-3 are each a portion of an AWS frequency band plan associated with next generation voice and data services and applications. The AWS-1 includes multiple frequency blocks, such as blocks A, B, C, D, E, and F. Each frequency block has an associated mobile frequency band and base frequency band. The portion 310 of the wireless spectrum 300 is associated with the base frequency band of the AWS-1 F block of the AWS frequency band plan. The AWS-1 F block includes frequencies from about 1745 megahertz (MHz) to about 2155 MHz and is used for downlink communication via a downlink portion 312 of a communication path between, for example, a base station (e.g., terrestrial antenna) and a mobile device. The AWS-1 F block is shown as being adjacent to the AWS-3 portion of the AWS frequency band plan.

    [0030] The J block is a frequency band being proposed for use with an AWS-2 portion (not shown) of the AWS frequency band plan. The J block includes frequencies from about 2175 MHz to about 2180 MHz. The J block is shown as being adjacent to the AWS-3 portion of the AWS frequency band plan and adjacent to the MSS-1 portion of the wireless spectrum 300. The J block is used for downlink communication via a downlink portion 332 of a communication path between, for example, a terrestrial antenna and a mobile device.

    [0031] Each of the MSS-1 and MSS-2 is a portion of the wireless spectrum 300 that is used for mobile satellite services systems. The MSS-1 portion of the wireless spectrum 300 is associated with a frequency band that includes frequencies from about 2180 MHz to about 2190 MHz. The MSS-2 portion of the wireless spectrum 300 is associated with a frequency band that includes frequencies from about 2190 MHz to about 2200 MHz. Each of the MSS-1 and MSS-2 portions of the wireless spectrum 300 can be used in hybrid satellite/terrestrial wireless communication systems, for example. The MSS-1 portion of the wireless spectrum 300 is used for downlink communication via a downlink portion 342 of a communication path between, for example, a base station or a satellite, and a mobile device. The MSS-2 portion of the wireless spectrum 300 is used for downlink communication via a downlink portion 352 of a communication path between, for example, a base station or a satellite, and a mobile device. The MSS-1 portion of the wireless spectrum 300 is shown as being adjacent to the J block and adjacent to the MSS-2 portion of the wireless spectrum 300. The MSS-2 portion of the wireless spectrum 300 is shown as being adjacent to the MSS-1 portion of the wireless spectrum 300.

    [0032] The AWS-3 portion of the AWS frequency band plan is being proposed for flexible-use spectrum services and applications. The AWS-3 portion of the AWS frequency band plan can be used for services and applications that use different communication methods. For example, the AWS-3 portion of the AWS frequency band plan can be used for an asymmetric TDD communication scheme via a communication path between, for example, a base station or a satellite, and a mobile device. The communication path associated with the asymmetric TDD communication scheme includes a downlink portion 322 and an uplink portion 324. Because the AWS-3 portion of the AWS frequency band plan is adjacent to the AWS-1 F block and the J block, it is desirable that the downlink portion 322 and the uplink portion 324 be configured such that minimal (if any) interference occurs between the frequency band associated with the AWS-3 portion of the AWS frequency band plan and the frequency bands associated with the AWS-1 F block and the J block.

    [0033] FIG. 4 is a diagram illustrating aspects of an asymmetric TDD communication scheme for use in the AWS-3 portion of the wireless spectrum 300 described above with respect to FIG. 3, according to an example. The asymmetric TDD communication scheme allocates or assigns frequencies from about 2160 MHz to about 2170 MHz to a first portion 410 of a frequency band 440 and associated with a frequency band 430. The asymmetric TDD communication scheme also allocates or assigns frequencies from about 2155 MHz to about 2175 MHz to a second portion 420 associated with the frequency band 440. The first portion 410 is different from the second portion 420 of the asymmetric TDD communication scheme. For example, a spectrum bandwidth associated with the frequency band 440 of the second portion 420 is larger than a spectrum bandwidth associated with the frequency band 420 of the first portion 410.

    [0034] The first portion 410 is associated with an uplink portion or uplink communication portion (↑) of the asymmetric TDD communication scheme. The first portion 410 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t1 and t2. The second portion 420 is associated with a downlink portion or downlink communication portion (↓) of the asymmetric TDD communication scheme. The second portion 420 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances t0 and t1. In some examples, the interval between time instances t1 and t2 can have substantially the same duration as the interval between time instances t0 and t1. In other examples, the interval between time instances t1 and t2 can have a different duration than the duration of the interval between time instances t0 and t1.

    [0035] Asymmetric data flow in the TDD communication scheme occurs when a time-bandwidth product associated with the first portion 410 is different from a time-bandwidth product associated with the second portion 420. The time-bandwidth product associated with the first portion 410 refers to the product of TU and the spectrum bandwidth associated with the frequency band 430. The time-bandwidth product associated with the first portion 410 is proportional to the amount of data that can flow in the direction of the first portion 410. The time-bandwidth product associated with the second portion 420 refers to the product of To and the spectrum bandwidth associated with the frequency band 440. The time-bandwidth product associated with the second portion 420 is proportional to the amount of data that can flow in the direction of the second portion 420. When TU and TD are substantially the same, the amount of data flow in a given direction is proportional to the spectrum bandwidth of the frequency band associated with that direction. In this example, when TU and TD are substantially the same, the amount of data flow is larger in the downlink direction associated with the second portion 420 of the asymmetric TDD communication scheme than in the uplink direction associated with the first portion 410 of the asymmetric TDD communication scheme.

    [0036] The asymmetric TDD communication scheme also includes an uplink guard band 450 that separates the first portion 410 from a frequency band (e.g., AWS-1 F block) that is adjacent to the 2155 MHz frequency of the frequency band 440. The asymmetric TDD communication scheme further includes an uplink guard band 460 that separates the first portion 410 from a frequency band (e.g., J block) that is adjacent to the 2175 MHz frequency of the frequency band 440. The uplink guard bands 450 and 460 are used to minimize or reduce the interference that can occur between the downlink portions of the adjacent frequency bands and the uplink portion of the asymmetric TDD communication scheme described in FIG. 4.

    [0037] FIGS. 5A-5B are each a diagram depicting the time and frequency aspects of a TDD scheme with adjacent FDD schemes, according to examples. FIG. 5A shows a diagram 500 that illustrates a first frequency band 504 associated with a TDD communication path. The TDD communication path can be symmetric or asymmetric. In some examples, it may be desirable that the TDD communication path be asymmetric to be used in next generation applications and services. The diagram 500 also illustrates a second frequency band 502 associated with an uplink portion of an FDD communication path and a third frequency band 506 associated with a downlink portion of an FDD communication path. The second frequency band 502 and the third frequency band 506 need not (but can) be paired FDD frequency bands associated with the same FDD communication path.

    [0038] The first frequency band 504 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f4. The second frequency band 502 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 506 is associated with a spectrum bandwidth that includes frequencies in the range f4 to f5. The first frequency band 504 is adjacent to the second frequency band 502 (e.g., at f1). The first frequency band 504 is adjacent to the third frequency band 506 (e.g., at f4). The first frequency band 504, the second frequency band 502, and the third frequency band 506 can be mutually exclusive frequency bands. In some examples, the first frequency band 504, the second frequency band 502, and the third frequency band 506 are wireless frequency bands.

    [0039] The first frequency band 504 includes a first portion 510 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first frequency band 504 includes a second portion 512 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f4. The first portion 510 of the first frequency band 504 is different from the second portion 512 of the first frequency band 504 and overlaps the second portion 512 of the first frequency band 504. The spectrum bandwidth associated with the first portion 510 of the first frequency band 504 can be different (or the same) from the spectrum bandwidth associated with the second portion 512 of the first frequency band 504.

    [0040] The first portion 510 of the first frequency band 504 is associated with an uplink portion or uplink communication portion of the TDD communication path. The first portion 510 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t1 and t2. The second portion 512 of the first frequency band 504 is associated with a downlink portion or downlink communication portion of the TDD communication path. The second portion 512 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances t0 and t1.

    [0041] When the time-bandwidth product associated with the first portion 510 of the first frequency band 504 is substantially the same as the time-bandwidth product associated with the second portion 512 of the first frequency band 504, the TDD communication path associated with the first frequency band 504 operates as a symmetric TDD communication path. The time-bandwidth product associated with the first portion 510 of the first frequency band 504 refers to the product of TU and the spectrum bandwidth between frequencies f1 and f3. The time-bandwidth product associated with the second portion 512 of the first frequency band 504 refers to the product of TD and the spectrum bandwidth between frequencies f2 and f4. When the time-bandwidth product associated with the first portion 510 of the first frequency band 504 is different from the time-bandwidth product associated with the second portion 512 of the first frequency band 504, the TDD communication path associated with the first frequency band 504 operates as an asymmetric TDD communication path.

    [0042] FIG. 5A shows the first portion 510 of the first frequency band 504 as being adjacent to the second frequency band 502 and separate from the third frequency band 506 by an uplink guard band 516. Because the first portion 510 of the first frequency band 504 and the uplink portion of the FDD communication path associated with the second frequency band 502 are both either transmitting or receiving signals in a same direction, no guard band may be desirable between the first portion 510 of the first frequency band 504 and the second frequency band 502 given that minimal (if any) interference occurs. On the other hand, the first portion 510 of the first frequency band 504 and the downlink portion of the FDD communication link associated with the third frequency band 506 may need a guard band (e.g., uplink guard band 516) because they are either transmitting or receiving signals in opposite directions, which may result in significant levels of interference.

    [0043] Similarly, the second portion 512 of the first frequency band 504 is shown as being adjacent to the third frequency band 506 and separate from the second frequency band 502 by a downlink guard band 514. Because the second portion 512 of the first frequency band 504 and the downlink portion of the FDD communication path associated with the third frequency band 506 are both either transmitting or receiving signals in a same direction, no guard band may be desirable given that minimal (if any) interference occurs between the second portion 512 of the first frequency band 504 and the third frequency band 506. On the other hand, the second portion 512 of the first frequency band 504 and the uplink portion of the FDD communication path associated with the second frequency band 502 may need a guard band (e.g., downlink guard band 514) because they are either transmitting or receiving signals in opposite directions, which may result in significant levels of interference. The uplink guard band 516 and the downlink guard band 514 need not (but can) have the same spectrum bandwidth.

    [0044] FIG. 5B shows a diagram 520 that illustrates a first frequency band 524 associated with a TDD communication path. The diagram 520 also illustrates a second frequency band 522 associated with a downlink portion of an FDD communication path and a third frequency band 526 associated with an uplink portion of an FDD communication path. The second frequency band 522 and the third frequency band 526 need not (but can) be paired FDD frequency bands associated with the same FDD communication path.

    [0045] The first frequency band 524, the second frequency band 522, and the third frequency band 526 are similar to the first frequency band 504, the second frequency band 502, and the third frequency band 506 described above with respect to FIG. 5A. The first frequency band 524 includes a first portion 530 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f4. The first frequency band 524 includes a second portion 532 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first portion 530 of the first frequency band 524 is different from the second portion 532 of the first frequency band 524 and overlaps the second portion 532 of the first frequency band 524. The spectrum bandwidth associated with the first portion 530 of the first frequency band 524 can be different (or the same) from the spectrum bandwidth associated with the second portion 532 of the first frequency band 524.

    [0046] The first portion 530 of the first frequency band 524 is associated with an uplink portion of the TDD communication path and has an associated uplink time slot, TU, described above with respect to FIG. 5A. The second portion 532 of the first frequency band 524 is associated with a downlink portion of the TDD communication path and has an associated downlink time slot, TD, also described above with respect to FIG. 5A. The TDD communication path associated with the first frequency 524 can be symmetric or asymmetric based on the time-bandwidth product associated with the first portion 530 of the first frequency band 524 and the time-bandwidth product associated with the second portion 532 of the first frequency band 524.

    [0047] FIG. 5B shows the first portion 530 of the first frequency band 524 as being adjacent to the third frequency band 526 and separate from the second frequency band 524 by an uplink guard band 534. The first portion 530 of the first frequency band 524 and the downlink portion of the FDD communication path associated with the second frequency band 524 may need a guard band because they are either transmitting or receiving signals in opposite directions, which may result in significant levels of interference.

    [0048] Similarly, the second portion 532 of the first frequency band 524 is shown as being adjacent to the second frequency band 522 and separate from the third frequency band 526 by a downlink guard band 536. The second portion 532 of the first frequency band 524 and the uplink portion of the FDD communication path associated with the third frequency band 526 may need a guard band because they are either transmitting or receiving signals in opposite directions, which may result in significant levels of interference. The uplink guard band 534 and the downlink guard band 536 need not (but can) have the same spectrum bandwidth.

    [0049] FIGS. 6A-6B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD schemes, according to other examples. FIG. 6A shows a diagram 600 that illustrates a first frequency band 604 associated with a TDD communication path. The diagram 600 also illustrates a second frequency band 602 associated with an uplink portion of an FDD communication path and a third frequency band 606 associated with an uplink portion of an FDD communication path different from the FDD communication path associated with the second frequency band 602.

    [0050] The first frequency band 604 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f4. The second frequency band 602 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 606 is associated with a spectrum bandwidth that includes frequencies in the range f4 to f5. The first frequency band 604 is adjacent to the second frequency band 602 (e.g., at f1). The first frequency band 604 is adjacent to the third frequency band 606 (e.g., at f4). The first frequency band 604, the second frequency band 602, and the third frequency band 606 can be mutually exclusive frequency bands. In some examples, the first frequency band 604, the second frequency band 602, and the third frequency band 606 are wireless frequency bands.

    [0051] The first frequency band 604 includes a first portion 610 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f4. The first frequency band 604 includes a second portion 612 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first portion 610 of the first frequency band 604 is different from the second portion 612 of the first frequency band 604 and overlaps the second portion 612 of the first frequency band 604. The spectrum bandwidth associated with the first portion 610 of the first frequency band 604 is different from the spectrum bandwidth associated with the second portion 612 of the first frequency band 604.

    [0052] The first portion 610 of the first frequency band 604 is associated with an uplink portion or uplink communication portion of the TDD communication path. The first portion 610 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t1 and t2. The second portion 612 of the first frequency band 604 is associated with a downlink portion or downlink communication portion of the TDD communication path. The second portion 612 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances to and t1.

    [0053] When the time-bandwidth product associated with the first portion 610 of the first frequency band 604 is substantially the same as the time-bandwidth product associated with the second portion 612 of the first frequency band 604, the TDD communication path associated with the first frequency band 604 operates as a symmetric TDD communication path. When the time-bandwidth product associated with the first portion 610 of the first frequency band 604 is different from the time-bandwidth product associated with the second portion 612 of the first frequency band 604, the TDD communication path associated with the first frequency band 604 operates as an asymmetric TDD communication path. Because the spectrum bandwidth associated with the first portion 610 of the first frequency band 604 is different from the spectrum bandwidth associated with the second portion 612 of the first frequency band 604, when the time intervals associated with the time slots TU and TD are the same, the TDD communication path associated with the first frequency band 604 operates as an asymmetric TDD communication path.

    [0054] FIG. 6A shows the first portion 610 of the first frequency band 604 as being adjacent to the second frequency band 602 and to the third frequency band 606. Because the first portion 610 of the first frequency band 604, the uplink portion of the FDD communication path associated with the second frequency band 602, and the uplink portion of the FDD communication path associated with the second frequency band 606 are either transmitting or receiving signals in a same direction, no guard band may be desirable given that minimal (if any) interference may occur.

    [0055] The second portion 612 of the first frequency band 604 is shown as being separated from the second frequency band 602 by a downlink guard band 614 and separate from the third frequency band 606 by a downlink guard band 616. The downlink guard bands 614 and 616 may be desirable because the second portion 612 of the first frequency band 604, the uplink portion of the FDD communication path associated with the second frequency band 602, and the uplink portion of the FDD communication path associated with the second frequency band 606 are either transmitting or receiving signals in opposite directions, which may result in significant levels of interference. The downlink guard band 614 and 616 need not (but can) have the same spectrum bandwidth.

    [0056] FIG. 6B shows a diagram 620 that illustrates a first frequency band 624 associated with a TDD communication path. The diagram 620 also illustrates a second frequency band 622 associated with a downlink portion of an FDD communication path and a third frequency band 626 associated with a downlink portion of an FDD communication path different from the FDD communication path associated with the second frequency band 622.

    [0057] The first frequency band 624, the second frequency band 622, and the third frequency band 626 are similar to the first frequency band 604, the second frequency band 602, and the third frequency band 606 described above with respect to FIG. 6A. The first frequency band 624 includes a first portion 630 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first frequency band 624 includes a second portion 632 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f4. The first portion 630 of the first frequency band 624 is different from the second portion 632 of the first frequency band 624 and overlaps the second portion 632 of the first frequency band 624. The spectrum bandwidth associated with the first portion 630 of the first frequency band 624 is different from the spectrum bandwidth associated with the second portion 632 of the first frequency band 624.

    [0058] The first portion 630 of the first frequency band 624 is associated with an uplink portion of the TDD communication path and has an associated uplink time slot, TU, described above with respect to FIG. 6A. The second portion 632 of the first frequency band 624 is associated with a downlink portion of the TDD communication path and has an associated downlink time slot, TD, also described above with respect to FIG. 6A. The TDD communication path associated with the first frequency 624 can be symmetric or asymmetric based on the time-bandwidth product associated with the first portion 630 of the first frequency band 624 and the time-bandwidth product associated with the second portion 632 of the first frequency band 624. Because the spectrum bandwidth associated with the first portion 630 of the first frequency band 624 is different from the spectrum bandwidth associated with the second portion 632 of the first frequency band 624, when the time intervals associated with the time slots TU and TD are the same, the TDD communication path associated with the first frequency band 624 operates as an asymmetric TDD communication path.

    [0059] FIG. 6B shows the first portion 630 of the first frequency band 624 as being separated from the second frequency band 622 by an uplink guard band 634 and separate from the third frequency band 626 by an uplink guard band 636. The uplink guard bands 634 and 636 need not (but can) have the same spectrum bandwidth. The second portion 632 of the first frequency band 624 is shown as being adjacent to the second frequency band 622 and adjacent to the third frequency band 626.

    [0060] FIGS. 7A-7B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD and synchronous TDD schemes, according to examples. FIG. 7A shows a diagram 700 that illustrates a first frequency band 704 associated with a TDD communication path. The diagram 700 illustrates a second frequency band 702 associated with a TDD communication path that is synchronized to the TDD communication path in the first frequency band 704. The diagram 700 also illustrates a third frequency band 706 associated with an uplink portion of an FDD communication path.

    [0061] The first frequency band 704 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f3. The second frequency band 702 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 706 is associated with a spectrum bandwidth than includes frequencies between frequencies f3 and f4. The first frequency band 704 is adjacent to the second frequency band 702 (e.g., at f1). The first frequency band 704 is also adjacent to the third frequency band 706 (e.g., at f3). The first frequency band 704, the second frequency band 702, and the third frequency band 706 can be mutually exclusive frequency bands. In some embodiments, the first frequency band 704, the second frequency band 702, and the third frequency band 706 are wireless frequency bands.

    [0062] The first frequency band 704 includes a first portion 710 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first frequency band 704 includes a second portion 712 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f2. The first portion 710 of the first frequency band 704 is different from the second portion 712 of the first frequency band 704 and overlaps the second portion 712 of the first frequency band 704. The spectrum bandwidth associated with the first portion 710 of the first frequency band 704 is different from the spectrum bandwidth associated with the second portion 712 of the first frequency band 704.

    [0063] The first portion 710 of the first frequency band 704 is associated with an uplink portion or uplink communication portion of the TDD communication path. The first portion 710 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t1 and t2. The second portion 712 of the first frequency band 704 is associated with a downlink portion or downlink communication portion of the TDD communication path. The second portion 712 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances to and t1.

    [0064] When the time-bandwidth product associated with the first portion 710 of the first frequency band 704 is substantially the same as the time-bandwidth product associated with the second portion 712 of the first frequency band 704, the TDD communication path associated with the first frequency band 704 operates as a symmetric TDD communication path. When the time-bandwidth product associated with the first portion 710 of the first frequency band 704 is different from the time-bandwidth product associated with the second portion 712 of the first frequency band 704, the TDD communication path associated with the first frequency band 704 operates as an asymmetric TDD communication path.

    [0065] FIG. 7A shows the first portion 710 of the first frequency band 704 as being adjacent to the second frequency band 702. The synchronized or synchronous TDD communication path in the second frequency band 702 has an uplink portion (not shown) and a downlink portion (not shown) that operate at substantially the same time intervals (i.e., synchronously) as the time intervals TU and TD of the first portion 710 and the second portion 712 of the first frequency band 704, respectively. As a result, the first portion 710 of the first frequency band 704 and the synchronous TDD communication path associated with the second frequency band 702 are both either transmitting or receiving signals in a same direction and no guard band may be desirable given that minimal (if any) interference occurs between the first portion 710 of the first frequency band 704 and the second frequency band 702.

    [0066] The first portion 710 of the first frequency band 704 is also adjacent to the third frequency band 706. The first portion 710 of the first frequency band 704 and the uplink portion of the FDD communication path associated with the third frequency band 706 need no guard band because they are either transmitting or receiving signals in the same direction with minimal or no interference between the frequency bands.

    [0067] The second portion 712 of the first frequency band 704 is shown as being adjacent to the second frequency band 702 and separate from the third frequency band 706 by a downlink guard band 714. No guard band is needed between the second portion 712 of the first frequency band 704 and the synchronous TDD communication path associated with the second frequency band 702. The downlink guard band 704, however, is needed because the second portion 712 of the first frequency band 704 and the uplink portion of the FDD communication path associated with the third frequency band 706 are transmitting or receiving signals in opposite directions.

    [0068] FIG. 7B shows a diagram 720 according to the invention that illustrates a first frequency band 724 associated with a TDD communication path. The diagram 720 also illustrates a second frequency band 722 associated with an uplink portion of an FDD communication path and a third frequency band 726 associated with a synchronous TDD communication path.

    [0069] The first frequency band 724, the second frequency band 722, and the third frequency band 726 are similar to the first frequency band 704, the second frequency band 702, and the third frequency band 706 described above with respect to FIG. 7A. The first frequency band 724 includes a first portion 730 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first frequency band 724 includes a second portion 732 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first portion 730 of the first frequency band 724 is different from the second portion 732 of the first frequency band 724 and overlaps the second portion 732 of the first frequency band 724. The spectrum bandwidth associated with the first portion 730 of the first frequency band 724 is different from the spectrum bandwidth associated with the second portion 732 of the first frequency band 724.

    [0070] The first portion 730 of the first frequency band 724 is associated with an uplink portion of the TDD communication path and has an associated uplink time slot, TU, described above with respect to FIG. 7A. The second portion 732 of the first frequency band 724 is associated with a downlink portion of the TDD communication path and has an associated downlink time slot, TD, also described above with respect to FIG. 7A. The TDD communication path associated with the first frequency 724 can be symmetric or asymmetric based on the time-bandwidth product associated with the first portion 730 of the first frequency band 724 and the time-bandwidth product associated with the second portion 732 of the first frequency band 724.

    [0071] FIG. 7B shows the first portion 730 of the first frequency band 724 as being adjacent to the second frequency band 722 and adjacent to the third frequency band 726. The first portion 730 of the first frequency band 724 and the uplink portion of the FDD communication link associated with the second frequency band 722 need no guard band because they are either transmitting or receiving signals in the same direction with minimal (if any) interference. Similarly, the first portion 730 of the first frequency band 724 and the synchronous TDD communication path associated with the third frequency band 726 need no guard band because they are synchronously transmitting or receiving signals in the same direction.

    [0072] The second portion 732 of the first frequency band 724 is shown as being separated from the second frequency band 722 by a downlink guard band 734 and adjacent to the third frequency band 726. The second portion 732 of the first frequency band 724 and the uplink portion of the FDD communication path associated with the second frequency band 722 may need a guard band because they are either transmitting or receiving signals in opposite directions and are likely to interfere with each other. The second portion 732 of the first frequency band 724 and the synchronous TDD communication path associated with the third frequency band 726 do not need a guard band because they are synchronously transmitting or receiving signals in the same direction

    [0073] FIGS. 7C-7D are each a diagram depicting time and frequency aspects of an asymmetric TDD scheme with adjacent FDD and synchronous TDD schemes, according other embodiments. FIG. 7C shows a diagram 740 that illustrates a first frequency band 744 associated with a TDD communication path that can be symmetric or asymmetric. The diagram 740 also illustrates a second frequency band 742 associated with a TDD communication path that is synchronized to the TDD communication path in the first frequency band 744. The diagram 740 also illustrates a third frequency band 706 associated with a downlink portion of an FDD communication path.

    [0074] The first frequency band 744 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f3. The second frequency band 742 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 746 is associated with a spectrum bandwidth that includes frequencies in the range f3 to f4. The first frequency band 744 is adjacent to the second frequency band 742 (e.g., at fi). The first frequency band 744 is adjacent to the third frequency band 746 (e.g., at f3). The first frequency band 744, the second frequency band 742, and the third frequency band 746 can be mutually exclusive frequency bands. In some embodiments, the first frequency band 744, the second frequency band 742, and the third frequency band 746 are wireless frequency bands.

    [0075] The first frequency band 744 includes a first portion 750 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f2. The first frequency band 744 includes a second portion 752 that has allocated or assigned a spectrum bandwidth including frequencies between frequencies f1 and f3. The first portion 750 of the first frequency band 744 is different from the second portion 752 of the first frequency band 744 and overlaps the second portion 752 of the first frequency band 744. The spectrum bandwidth associated with the first portion 750 of the first frequency band 744 is different from the spectrum bandwidth associated with the second portion 752 of the first frequency band 744.

    [0076] The first portion 750 of the first frequency band 744 is associated with an uplink portion or uplink communication portion of the TDD communication path. The first portion 750 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t1 and t2. The second portion 752 of the first frequency band 744 is associated with a downlink portion or downlink communication portion of the TDD communication path. The second portion 752 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances t0 and t1.

    [0077] When the time-bandwidth product associated with the first portion 750 of the first frequency band 744 is substantially the same as the time-bandwidth product associated with the second portion 752 of the first frequency band 744, the TDD communication path associated with the first frequency band 744 operates as a symmetric TDD communication path. When the time-bandwidth product associated with the first portion 750 of the first frequency band 744 is different from the time-bandwidth product associated with the second portion 752 of the first frequency band 744, the TDD communication path associated with the first frequency band 744 operates as an asymmetric TDD communication path.

    [0078] FIG. 7C shows the first portion 750 of the first frequency band 744 as being adjacent to the second frequency band 742. The synchronized or synchronous TDD communication path in the second frequency band 742 has an uplink portion (not shown) and a downlink portion (not shown) that operate at substantially the same time intervals (i.e., synchronously) as the time intervals TU and TD of the first portion 750 and the second portion 752 of the first frequency band 744, respectively. As a result, the first portion 750 of the first frequency band 744 and the synchronous TDD communication path associated with the second frequency band 742 are both either transmitting or receiving signals in a same direction and no guard band may be desirable given that minimal (if any) interference occurs between the first portion 750 of the first frequency band 744 and the second frequency band 742.

    [0079] The first portion 750 of the first frequency band 744 is separate from the third frequency band 746 by an uplink guard band 754 because the first portion 750 of the first frequency band 744 and the FDD communication path associated with third frequency band 746 are transmitting or receiving signals in the opposite directions. The second portion 752 of the first frequency band 744 is shown as being adjacent to the second frequency band 742 and adjacent to the third frequency band 746.

    [0080] FIG. 7D shows a diagram 760 according to the invention that illustrates a first frequency band 764 associated with a TDD communication path. The diagram 760 also illustrates a second frequency band 762 associated with a downlink portion of an FDD communication path and a third frequency band 766 associated with a synchronous TDD communication path.

    [0081] The first frequency band 764, the second frequency band 762, and the third frequency band 766 are similar to the first frequency band 744, the second frequency band 742, and the third frequency band 746 described above with respect to FIG. 7C. The first frequency band 764 includes a first portion 770 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first frequency band 764 includes a second portion 772 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first portion 770 of the first frequency band 764 is different from the second portion 772 of the first frequency band 764 and overlaps the second portion 772 of the first frequency band 764. The spectrum bandwidth associated with the first portion 770 of the first frequency band 764 is different from the spectrum bandwidth associated with the second portion 772 of the first frequency band 764.

    [0082] The first portion 770 of the first frequency band 764 is associated with an uplink portion of the TDD communication path and has an associated uplink time slot, TU, described above with respect to FIG. 7C. The second portion 772 of the first frequency band 764 is associated with a downlink portion of the TDD communication path and has an associated downlink time slot, TD, also described above with respect to FIG. 7C. The TDD communication path associated with the first frequency band 764 can be symmetric or asymmetric based on the time-bandwidth product associated with the first portion 770 of the first frequency band 764 and the time-bandwidth product associated with the second portion 772 of the first frequency band 764.

    [0083] FIG. 7D shows the first portion 770 of the first frequency band 764 as being separated from the second frequency band 762 by an uplink guard band 774. The first portion 770 of the first frequency band 764 is adjacent to the third frequency band 766. The second portion 772 of the first frequency band 764 is shown as being adjacent to the second frequency band 762 and adjacent to the third frequency band 766.

    [0084] FIGS. 8A-8B are diagrams each depicting time and frequency aspects of a TDD scheme with adjacent synchronous TDD and asynchronous TDD schemes, according to examples. FIG. 8A shows a diagram 800 that illustrates a first frequency band 804 associated with a TDD communication path. The diagram 800 illustrates a second frequency band 802 associated with a TDD communication path that is asynchronous with the TDD communication path in the first frequency band 804. The diagram 800 also illustrates a third frequency band 806 associated with a TDD communication path that is synchronous with the TDD communication path in the first frequency band 804.

    [0085] The first frequency band 804 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f3. The second frequency band 802 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 806 is associated with a spectrum bandwidth that includes frequencies in the range f3 to f4. The first frequency band 804 is adjacent to the second frequency band 802 (e.g., at f1). The first frequency band 804 is adjacent to the third frequency band 806 (e.g., at f3). The first frequency band 804, the second frequency band 802, and the third frequency band 806 can be mutually exclusive frequency bands. In some examples, the first frequency band 804, the second frequency band 802, and the third frequency band 806 are wireless frequency bands.

    [0086] In this example, the first frequency band 804 includes a first portion 810 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first frequency band 804 includes a second portion 812, which is also shown as being associated with the spectrum bandwidth that includes frequencies in the range f2 to f3. The spectrum bandwidth associated with the first portion 810 of the first frequency band 804, however, need not be the same as the spectrum bandwidth associated with the second portion 812 of the first frequency band 804.

    [0087] The first portion 810 of the first frequency band 804 is associated with an uplink portion or uplink communication portion of the TDD communication path. The first portion 810 has an uplink time interval or uplink time slot, TU, associated with the interval between time instances t3 and t5. The second portion 812 of the first frequency band 804 is associated with a downlink portion or downlink communication portion of the TDD communication path. The second portion 812 has a downlink time interval or downlink time slot, TD, associated with the interval between time instances t1 and t3.

    [0088] When the time-bandwidth product associated with the first portion 810 of the first frequency band 804 is substantially the same as the time-bandwidth product associated with the second portion 812 of the first frequency band 804, the TDD communication path associated with the first frequency band 804 operates as a symmetric TDD communication path. When the time-bandwidth product associated with the first portion 810 of the first frequency band 804 is different from the time-bandwidth product associated with the second portion 812 of the first frequency band 844, the TDD communication path associated with the first frequency band 844 operates as an asymmetric TDD communication path.

    [0089] FIG. 8A shows the first portion 810 of the first frequency band 804 as being adjacent to the third frequency band 806. The synchronized or synchronous TDD communication path in the third frequency band 806 has an uplink portion (not shown) and a downlink portion (not shown) that operate at substantially the same time intervals (i.e., synchronously) as the time intervals TU and TD of the first portion 810 and the second portion 812 of the first frequency band 804, respectively. As a result, the first portion 810 of the first frequency band 804 and the synchronous TDD communication path associated with the third frequency band 806 are both either transmitting or receiving signals in a same direction and no guard band may be desirable.

    [0090] The first portion 810 of the first frequency band 804 is separate from the second frequency band 802 by an uplink guard band 814 because the first portion 810 of the first frequency band 804 and the asynchronous TDD communication path associated with second frequency band 802 are offset in time. For example, an uplink portion 820 of the asynchronous TDD communication path associated with the second frequency band 802 has an uplink time slot or time interval between time instances t2 and t4. The uplink time slot associated with the uplink portion 820 of the second frequency band 802 is temporally offset or misaligned with the uplink time slot, TU, associated with the first portion 810 of the first frequency band 804. This temporal offset can result in interference between the second frequency band 802 and the first frequency band 804 as at least a portion of the uplink portion 820 of the second frequency band 802 occurs during the second portion 812 of the first frequency band 804.

    [0091] The second portion 812 of the first frequency band 804 is shown as being adjacent to the third frequency band 806. The second portion 812 of the first frequency band 804 and the synchronous TDD communication path associated with the third frequency band 806 are both either transmitting or receiving signals in a same direction and no guard band may be desirable. The second portion 812 of the first frequency band 804 is separate from the second frequency band 802 by a downlink guard band 816 because the second portion 812 of the first frequency band 804 and the asynchronous TDD communication path associated with second frequency band 802 are offset in time. For example, a downlink portion 822 of the asynchronous TDD communication path associated with the second frequency band 802 has a downlink time slot or time interval between time instances t0 and t2. The downlink time slot associated with the downlink portion 822 of the second frequency band 802 is temporally offset or misaligned with the downlink time slot, TD, associated with the second portion 812 of the first frequency band 804. This temporal offset can result in interference between the second frequency band 802 and the first frequency band 804.

    [0092] FIG. 8B shows a diagram 840 that illustrates a first frequency band 844 associated with a TDD communication path. The diagram 840 also illustrates a second frequency band 842 associated with an asynchronous TDD communication path and a third frequency band 846 associated with a synchronous TDD communication path.

    [0093] The first frequency band 844, the second frequency band 842, and the third frequency band 846 are similar to the first frequency band 804, the second frequency band 802, and the third frequency band 806 described above with respect to FIG. 8A. A first portion 850 of the first frequency band 844 is similar to the first portion 810 of the first frequency band 804 described above with respect to FIG. 8A. A second portion 852 of the first frequency band 844 is similar to the second portion 812 of the first frequency band 804 described above with respect to FIG. 8A.

    [0094] FIG. 8B shows the first portion 850 of the first frequency band 844 and the second portion 852 of the first frequency band as being adjacent to the third frequency band 846. The first portion 850 of the first frequency band 844 is shown separate from the second frequency band 842 by an uplink guard band 854 because the first portion 850 of the first frequency band 844 and the asynchronous TDD communication path associated with second frequency band 842 are offset or misaligned in time (i.e., unsynchronized). For example, an uplink portion 860 of the asynchronous TDD communication path associated with the second frequency band 842 has an uplink time slot between time instances t3 and t5, while the uplink time slot, TU, of the first portion 850 of the first frequency band 844 is associated with time instances t2 and t4.

    [0095] Similarly, the second portion 852 of the first frequency band 844 is shown separate from the second frequency band 842 by a downlink guard band 856 because the second portion 860 of the first frequency band 844 and the asynchronous TDD communication path associated with second frequency band 842 are offset or misaligned in time. For example, a downlink portion 862 of the asynchronous TDD communication path associated with the second frequency band 842 has a downlink time slot between time instances t1 and t3, while the downlink time slot, TD, of the second portion 852 of the first frequency band 844 is associated with time instances t0 and t2.

    [0096] FIGS. 9A-9B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent synchronous TDD and temporally-asymmetric TDD schemes, according to examples. FIG. 9A shows a diagram 900 that illustrates a first frequency band 904 associated with a TDD communication path. The diagram 900 illustrates a second frequency band 902 associated with a temporally-asymmetric TDD communication path. The temporally-asymmetric TDD communication path can refer to a TDD communication path having an uplink time slot duration different from a downlink time slot duration. The diagram 900 further illustrates a third frequency band 906 associated with a TDD communication path that is synchronous with the TDD communication path in the first frequency band 904.

    [0097] The first frequency band 904 is associated with a spectrum bandwidth that includes frequencies in the range f1 to f3. The second frequency band 902 is associated with a spectrum bandwidth that includes frequencies in the range f0 to f1. The third frequency bandwidth 906 is associated with a spectrum bandwidth that includes frequencies in the range f3 to f4. The first frequency band 904 is adjacent to the second frequency band 902 (e.g., at f1). The first frequency band 904 is adjacent to the third frequency band 906 (e.g., at f3). The first frequency band 904, the second frequency band 902, and the third frequency band 906 can be mutually exclusive frequency bands. In some examples, the first frequency band 904, the second frequency band 902, and the third frequency band 906 are wireless frequency bands.

    [0098] The first frequency band 904 includes a first portion 910 that has allocated or assigned a spectrum bandwidth including frequencies in the range f2 to f3. The first frequency band 904 includes a second portion 912 that has allocated or assigned a spectrum bandwidth including frequencies in the range f1 to f3. The first portion 910 of the first frequency band 904 is different from the second portion 912 of the first frequency band 904. The spectrum bandwidth associated with the first portion 910 of the first frequency band 904 is different from the spectrum bandwidth associated with the second portion 912 of the first frequency band 904.

    [0099] The first portion 910 of the first frequency band 904 is associated with an uplink portion of the TDD communication path. The first portion 910 has an uplink time slot, TU, associated with the interval between time instances t1 and t3. The second portion 912 of the first frequency band 904 is associated with a downlink portion of the TDD communication path. The second portion 912 has a downlink time slot, TD, associated with the interval between time instances t0 and t1.

    [0100] The TDD communication path associated with the first frequency 904 is symmetric when a time-bandwidth product associated with the first portion 910 of the first frequency band 904 is substantially the same as a time-bandwidth product associated with the second portion 912 of the first frequency band 904. The TDD communication path associated with the first frequency 904 is asymmetric when the time-bandwidth product associated with the first portion 910 of the first frequency band 904 is different from the time-bandwidth product associated with the second portion 912 of the first frequency band 904.

    [0101] FIG. 9A shows the first portion 910 of the first frequency band 904 as being adjacent to the third frequency band 906. The synchronous TDD communication path in the third frequency band 906 has an uplink portion (not shown) and a downlink portion (not shown) that operate at substantially the same time intervals as the time intervals TU and TD of the first portion 910 and the second portion 912 of the first frequency band 904, respectively.

    [0102] The first portion 910 of the first frequency band 904 is separate from the second frequency band 902 by an uplink guard band 914 because the first portion 910 of the first frequency band 904 and the temporally-asymmetric TDD communication path associated with second frequency band 902 are offset in time. For example, an uplink portion 920 of the temporally-asymmetric TDD communication path associated with the second frequency band 802 has an uplink time slot or time interval between time instances t2 and t3. The uplink time slot associated with the uplink portion 920 of the second frequency band 902 is temporally offset or misaligned with the uplink time slot, TU, associated with the first portion 910 of the first frequency band 904. This temporal offset can result in interference between the second frequency band 902 and the first frequency band 904.

    [0103] The second portion 912 of the first frequency band 904 is shown as being adjacent to the second frequency band 902 and adjacent to the third frequency band 906. The second portion 912 of the first frequency band 904 and the synchronous TDD communication path associated with the third frequency band 906 are both either transmitting or receiving signals in a same direction and no guard band may be desirable. The second portion 912 of the first frequency band 904 and the second frequency band 902 need no guard band because the second portion 912 of the first frequency band 904 and the temporally-asymmetric TDD communication path associated with second frequency band 902 are transmitting or receiving signals at the same time. For example, a downlink portion 922 of the temporally-asymmetric TDD communication path associated with the second frequency band 902 has a downlink time slot between time instances t0 and t2. As a result, the downlink time slot associated with the downlink portion 922 of the second frequency band 902 and the downlink time slot, TD, associated with the second portion 912 of the first frequency band 904 are common over the time instances t0 and t1 associated with the downlink time slot, TD, and no guard band may be desirable.

    [0104] FIG. 9B shows a diagram 940 that illustrates a first frequency band 944 associated with a TDD communication path. The diagram 940 also illustrates a second frequency band 942 associated with a temporally-asymmetric TDD communication path and a third frequency band 946 associated with a synchronous TDD communication path.

    [0105] The first frequency band 944, the second frequency band 942, and the third frequency band 946 are similar to the first frequency band 904, the second frequency band 902, and the third frequency band 906 described above with respect to FIG. 9A. The first frequency band 944 has a first portion 950 associated with an uplink portion of the TDD communication path. The first frequency band 944 has a second portion 952 associated with a downlink portion of the TDD communication path. The second frequency band 942 has a first portion 960 associated with an uplink portion of the temporally-asymmetric TDD communication path. The second frequency band 942 has a second portion 962 associated with a downlink portion of the temporally-asymmetric TDD communication path.

    [0106] The first portion 950 of the first frequency band 944 is shown as being adjacent to the third frequency band 946 and adjacent to the second frequency band 942. The second portion 952 of the first frequency band 944 is shown as being adjacent to the third frequency band 946 and separate from the second frequency band 942 by a downlink guard band 954. The downlink guard band 954 may be desirable because the uplink portion 960 of the second frequency band 942 overlaps in time with the second portion 952 of the first frequency band 944 that is associated with the downlink portion of the TDD communication path.

    [0107] FIGS. 10A-10B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent temporally-asymmetric TDD schemes, according to an example. FIG. 10A shows a diagram 1000 that illustrates a first frequency band 1004 associated with a TDD communication path. The diagram 1000 also illustrates a second frequency band 1002 associated with a temporally-asymmetric TDD communication path. In this example, the temporally-asymmetric TDD communication path associated with the second frequency band 1002 has an uplink time slot duration that is shorter than a downlink time slot duration. For example, the uplink time slot is between time instances t2 and t3 and the downlink time slot is between time instances t0 and t2. The diagram 1000 further illustrates a third frequency band 1006 associated with a temporally-asymmetric TDD communication path different from that of the second frequency band 1002. In this example, the temporally-asymmetric TDD communication path associated with the third frequency band 1006 also has the same uplink time slot duration and the same downlink time slot duration as the temporally-asymmetric TDD communication path associated with the second frequency band 1002.

    [0108] The first frequency band 1004 includes a first portion 1010 and a second portion 1012. A spectrum bandwidth associated with the first portion 1010 of the first frequency band 1004 is smaller than a spectrum bandwidth associated with the second portion 1012 of the first frequency band 1004. The first portion 1010 of the first frequency band 1004 is associated with an uplink portion of the TDD communication path. The second portion 1012 of the first frequency band 1004 is associated with a downlink portion of the TDD communication path. The second frequency band 1002 includes an uplink portion 1020 and a downlink portion 1022 associated with the temporally-asymmetric TDD communication path. The third frequency band 1006 includes an uplink portion 1030 and a downlink portion 1032 associated with the temporally-asymmetric TDD communication path.

    [0109] FIG. 10A shows the first portion 1010 of the first frequency band 1004 as separate from the second frequency band 1002 by an uplink guard band 1014 and separate from the third frequency band 1006 by an uplink guard band 1016. The uplink guard bands 1014 and 1016 may be desirable because the downlink portion 1022 of the second frequency band 1002 and the downlink portion 1032 of the third frequency band 1006 temporally overlap the first portion 1010 of the first frequency band 1004 that is associated with the uplink portion of the TDD communication path such that interference may occur between the bands.

    [0110] Similarly, the second portion 1012 of the first frequency band 1004 is shown as adjacent to the second frequency band 1002 and adjacent to the third frequency band 1006. In this example, guard bands need not be used because the second portion 1012 of the first frequency band 1004 occurs during a time interval (e.g., between t0 and t1) that coincides with a time interval (e.g., between t0 and t2) associated with the downlink portion 1022 of the second frequency band 1002 and also associated with the downlink portion 1032 of the third frequency band 1006.

    [0111] FIG. 10B shows a diagram 1040 that illustrates a first frequency band 1044 associated with a TDD communication path. The diagram 1040 also illustrates a second frequency band 1042 associated with a temporally-asymmetric TDD communication path and a third frequency band 1046 associated with a different temporally-asymmetric TDD communication path. In this example, the temporally-asymmetric TDD communication path associated with the second frequency band 1042 and the temporally-asymmetric TDD communication path associated with the third frequency band 1046 each has an uplink time slot duration that is longer than a downlink time slot duration.

    [0112] The first frequency band 1044, the second frequency band 1042, and the third frequency band 1046 are similar to the first frequency band 1004, the second frequency band 1002, and the third frequency band 1006 described above with respect to FIG. 10A. The first frequency band 1044 has a first portion 1050 associated with an uplink portion of the TDD communication path. The first frequency band 1044 has a second portion 1052 associated with a downlink portion of the TDD communication path. The second frequency band 1042 has a first portion 1060 associated with an uplink portion of the temporally-asymmetric TDD communication path. The second frequency band 1042 has a second portion 1062 associated with a downlink portion of the temporally-asymmetric TDD communication path. The third frequency band 1046 has a first portion 1070 associated with an uplink portion of the temporally-asymmetric TDD communication path. The third frequency band 1046 has a second portion 1072 associated with a downlink portion of the temporally-asymmetric TDD communication path.

    [0113] The first portion 1050 of the first frequency band 1044 is shown as being adjacent to the third frequency band 1046 and adjacent to the second frequency band 1042. The second portion 1052 of the first frequency band 1044 is shown as being separated from to the third frequency band 1046 by a downlink guard band 1056 and separate from the second frequency band 1042 by a downlink guard band 1054. The downlink guard bands 1054 and 1056 may be desirable because the uplink portion 1060 of the second frequency band 1042 and the uplink portion 1070 of the third frequency band 1046 each overlaps in time (e.g., between t1 and t2) with the second portion 1052 of the first frequency band 1044 that is associated with the downlink portion of the TDD communication path.

    [0114] FIGS. 11A-11B are each a diagram depicting the time and frequency aspects of a TDD scheme with adjacent temporally-asymmetric TDD schemes, according examples. FIG. 11 A shows a diagram 1100 that illustrates a first frequency band 1104 associated with a TDD communication path. The TDD communication path can be symmetric or asymmetric. The diagram 1100 also illustrates a second frequency band 1102 associated with a temporally-asymmetric TDD communication path. In this example, the temporally-asymmetric TDD communication path associated with the second frequency band 1002 has an uplink time slot duration (e.g., between t3 and t4) that is shorter than a downlink time slot duration (e.g., between t0 and t3). The diagram 1100 further illustrates a third frequency band 1106 associated with a temporally-asymmetric TDD communication path. In this example, the temporally-asymmetric TDD communication path associated with the third frequency band 1106 has an uplink time slot duration (e.g., between t1 and t4) that is longer than a downlink time slot duration (e.g., between to and t1).

    [0115] The first frequency band 1104 includes a first portion 1110 and a second portion 1112. A spectrum bandwidth associated with the first portion 1110 of the first frequency band 1104 can be the same (or different) than a spectrum bandwidth associated with the second portion 1112 of the first frequency band 1104. The first portion 1110 of the first frequency band 1104 is associated with an uplink portion of the TDD communication path. The second portion 1112 of the first frequency band 1104 is associated with a downlink portion of the TDD communication path. The second frequency band 1102 includes an uplink portion 1120 and a downlink portion 1122 of the temporally-asymmetric TDD communication path. The third frequency band 1106 includes an uplink portion 1130 and a downlink portion 1132 of the temporally-asymmetric TDD communication path.

    [0116] FIG. 11A shows the first portion 1110 of the first frequency band 1104 as separate from the second frequency band 1102 by an uplink guard band 1114 and adjacent to the third frequency band 1106. The uplink guard band 1114 may be desirable because the downlink portion 1122 of the second frequency band 1102 temporally overlaps the first portion 1110 of the first frequency band 1104 that is associated with the uplink portion of the TDD communication path. Without the uplink guard band 1114, this temporal overlap can cause interference between communication schemes operating in the first frequency band 1104 and the second frequency band 1102.

    [0117] Similarly, the second portion 1112 of the first frequency band 1104 is shown as adjacent to the second frequency band 1102 and separate from the third frequency band 1106 by a downlink guard band 1116. The downlink guard band 1116 may be desirable because the uplink portion 1130 of the third frequency band 1106 temporally overlaps the second portion 1112 of the first frequency band 1104 that is associated with the downlink portion of the TDD communication path. Without the downlink guard band 1116, this temporal overlap can cause interference between communication schemes operating in the first frequency band 1104 and in the third frequency band 1106.

    [0118] FIG. 11B shows a diagram 1140 that illustrates a first frequency band 1144 associated with a TDD communication path. The diagram 1140 also illustrates a second frequency band 1142 associated with a temporally-asymmetric TDD communication path and a third frequency band 1146 associated with a different temporally-asymmetric TDD communication path. In this example, the temporally-asymmetric TDD communication path associated with the second frequency band 1142 has an uplink time slot duration (e.g., between t1 and t4) that is longer than a downlink time slot duration (e.g., between t0 and t1). The temporally-asymmetric TDD communication path associated with the third frequency band 1146 has an uplink time slot duration (e.g., between t3 and t4) that is shorter than a downlink time slot duration (e.g., between t0 and t3).

    [0119] The first frequency band 1144, the second frequency band 1142, and the third frequency band 1146 are similar to the first frequency band 1104, the second frequency band 1102, and the third frequency band 1106 described above with respect to FIG. 11A. The first frequency band 1144 has a first portion 1150 associated with an uplink portion of the TDD communication path. The first frequency band 1144 has a second portion 1152 associated with a downlink portion of the TDD communication path. The second frequency band 1142 has a first portion 1160 associated with an uplink portion of the temporally-asymmetric TDD communication path. The second frequency band 1142 has a second portion 1162 associated with a downlink portion of the temporally-asymmetric TDD communication path. The third frequency band 1146 has a first portion 1170 associated with an uplink portion of the temporally-asymmetric TDD communication path. The third frequency band 1146 has a second portion 1172 associated with a downlink portion of the temporally-asymmetric TDD communication path.

    [0120] The first portion 1150 of the first frequency band 1144 is shown as being adjacent to the second frequency band 1142 and separate from the third frequency band 1146 by an uplink guard band 1156. The uplink guard band 1156 may be desirable because the downlink portion 1172 of the third frequency band 1146 overlaps in time with the first portion 1150 of the first frequency band 1144 that is associated with the uplink portion of the TDD communication path. The second portion 1152 of the first frequency band 1144 is shown as being separated from to the second frequency band 1142 by a downlink guard band 1154 and adjacent to the third frequency band 1146. The downlink guard band 1154 may be desirable because the uplink portion 1160 of the second frequency band 1142 overlaps in time with the second portion 1152 of the first frequency band 1144 that is associated with the downlink portion of the TDD communication path.

    [0121] FIGS. 12A-12B are each a diagram depicting time and frequency aspects of a TDD scheme with adjacent FDD and broadcast schemes, according to examples. FIG. 12A shows a diagram 1200 that illustrates a first frequency band 1204 associated with a TDD communication path. The TDD communication path can be symmetric or asymmetric. The diagram 1200 also illustrates a second frequency band 1202 associated with a wireless broadcast. The diagram 1200 further illustrates a third frequency band 1206 associated with a downlink portion of an FDD communication path.

    [0122] The first frequency band 1204 includes a first portion 1210 and a second portion 1212. A spectrum bandwidth associated with the first portion 1210 of the first frequency band 1204 is different from a spectrum bandwidth associated with the second portion 1212 of the first frequency band 1204. The first portion 1210 of the first frequency band 1204 is associated with an uplink portion of the TDD communication path. The second portion 1212 of the first frequency band 1204 is associated with a downlink portion of the TDD communication path.

    [0123] FIG. 12A shows the first portion 1210 of the first frequency band 1204 as separate from the second frequency band 1202 by an uplink guard band 1214 and separate from the third frequency band 1206 by an uplink guard band 1216. The uplink guard band 1214 may be desirable because the wireless broadcast associated with the second frequency band 1202 could interfere with the first portion 1210 of the first frequency band 1204 associated with the uplink portion of the TDD communication path. Similarly, the uplink guard band 1216 may be desirable because the downlink portion of the FDD communication path associated with the second frequency band 1202 could interfere with the first portion 1210 of the first frequency band 1204 associated with the uplink portion of the TDD communication path. The second portion 1212 of the first frequency band 1204 is shown as being adjacent to both the second frequency band 1204 and adjacent to the third frequency band 1206.

    [0124] FIG. 12B shows a diagram 1220 that illustrates a first frequency band 1224 associated with a TDD communication path. The diagram 1220 also illustrates a second frequency band 1222 associated with a wireless broadcast and a third frequency band 1226 associated with an uplink portion of an FDD communication path.

    [0125] The first frequency band 1224, the second frequency band 1222, and the third frequency band 1226 are similar to the first frequency band 1204, the second frequency band 1202, and the third frequency band 1206 described above with respect to FIG. 12A. The first frequency band 1224 has a first portion 1230 associated with an uplink portion of the TDD communication path. The first frequency band 1224 has a second portion 1232 associated with a downlink portion of the TDD communication path.

    [0126] The first portion 1230 of the first frequency band 1224 is shown as being separated from the second frequency band 1222 by an uplink guard band 1234 and adjacent to the third frequency band 1226. The uplink guard band 1234 may be desirable because the wireless broadcast associated with the second frequency band could would interfere with the first portion 1230 of the first frequency band 1224 associated with the uplink portion of the TDD communication path. The second portion 1232 of the first frequency band 1224 is shown as being adjacent to the second frequency band 1222 and separate from the third frequency band 1226 by a downlink guard band 1236. The downlink guard band 1236 may be desirable because the uplink portion of the FDD communication path associated with the third frequency band 1226 could interfere with the second portion 1232 of the first frequency band 1224 that is associated with the downlink portion of the TDD communication path.

    [0127] FIG. 13 is a flow chart illustrating a method for using an asymmetric TDD scheme, according to an example. At 1310, after 1300, receiving signals via a portion of a first frequency band over an asymmetric TDD communication path associated with the first frequency band. The first frequency band and the associated asymmetric TDD communication path can be based on one or more examples or embodiments described herein with respect to FIGS. 3-12B. At 1320, transmitting signals via a different portion of the first frequency band over the asymmetric TDD communication path associated with the first frequency band. After 1320, the process proceeds to 1330.

    [0128] FIG. 14 is a flow chart illustrating a method for using an asymmetric TDD scheme, according to another example. At 1410, after 1400, an asymmetric TDD communication path is operated over a first frequency band. The first frequency band and the associated asymmetric TDD communication path can be based on one or more examples or embodiments described herein with respect to FIGS. 3-12B. At 1420, communicating signals via the first frequency band over the asymmetric TDD communication path associated with the first frequency band. After 1420, the process proceeds to 1430.

    [0129] FIG. 15 is a flow chart illustrating a method for using an asymmetric TDD scheme, according to yet another example. At 1510, after 1500, operating a first communication portion of an asymmetric TDD communication path via an uplink portion of a first frequency band. The first frequency band and the associated asymmetric TDD communication path can be based on one or more examples or embodiments described herein with respect to FIGS. 3-12B. At 1520, operating a second communication portion of the asymmetric TDD communication path via a downlink portion of the first frequency band. After 1520, the process proceeds to

    [0130] In one or more embodiments or examples, the communication methods associated with asymmetric TDD communication paths described above with respect to FIGS. 3-12B can be implemented in flexible-use spectrum. In one or more embodiments or examples, the communication methods associated with asymmetric TDD communication paths described above with respect to FIGS. 3-12B can be implemented in spectrum having a dedicated use.

    CONCLUSION



    [0131] While various embodiments of the invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. For example, the methods described herein can include various combinations and/or subcombinations of the components and/or features of the different embodiments described. Furthermore, the alternative embodiments do not contribute to the invention. Although described with reference to use with flexible-use spectrum for satellite, terrestrial, and/or hybrid wireless communication systems, it should be understood that the asymmetric TDD methods described herein can be used with frequency bands dedicated for particular use and for use with certain wireless communication systems. Moreover, the asymmetric TDD methods described herein can be used with frequency bands in wired communication systems.


    Claims

    1. A method, comprising:

    sending a first signal via a first portion (730, 770) of a first frequency band (724, 764),

    receiving a second signal via a second portion (732, 772) of the first frequency band (724, 764), wherein a bandwidth utilized by the second portion is different from a bandwidth utilized by the first portion,

    characterized by:

    the first frequency band (724, 764) being immediately adjacent to a second frequency band (722, 762),

    the first frequency band (724, 764) being immediately adjacent to a third frequency band (726, 766),

    the first frequency band (724, 764), the second frequency band (722, 762) and the third frequency band (726, 766) being mutually exclusive frequency bands,

    wherein:

    an asymmetric time division duplex (TDD) communication path is operable in the first frequency band (724, 764), wherein, for the asymmetric TDD communication path, a time-bandwidth product associated with the first portion (730, 770) of the first frequency band (724, 764) is different from the time-bandwidth product associated with the second portion (732, 772) of the first frequency band (724, 764),

    a frequency division duplex (FDD) communication path is operable in the second frequency band (722, 762),

    a synchronous TDD communication path that is synchronized to the TDD communication path in the first frequency band is operable in the third frequency band (726, 766); and

    wherein:

    the first portion (730, 770) of the first frequency band (724, 764) occurs during a first time interval (TU),

    the second portion (732, 772) of the first frequency band (724, 764) occurs during a second time interval (TD), and

    wherein:

    a) the first portion (730) is contiguous with each of the second frequency band (722) and the third frequency band (726) during the first time interval (TU), and the second portion (732) is contiguous with only the third frequency band (726) during a second time interval (TD); the second portion (732) of the first frequency band (724) being separated from the third frequency band (726) by a first guard band (734) that is part of the first frequency band (724), wherein the first guard band (734) is located where the second portion (732) of the first frequency band (724) and the third frequency band (726) are transmitting or receiving signals in opposite directions or

    b) the first portion (770) is contiguous with only the third frequency band (766) during the first time interval (TU) with a second guard band (774) being positioned between the first portion (770) of the first frequency band (764) and the second frequency band (762) and with the second guard band (774) being part of the first frequency band (764), wherein the second guard band (774) is located where the first portion (770) of the first frequency band (764) and the third frequency band (766) are transmitting or receiving signals in opposite directions, and the second portion (772) is contiguous with each of the second frequency band (762) and the third frequency band (766) during the second time interval (TD).


     
    2. The method of claim 1, wherein a synchronous TDD uplink portion and a synchronous TDD downlink portion are operable in the third frequency band (726, 766).
     
    3. The method of claims 1 or 2, wherein the first time interval (TU) has a same duration as the second time interval (TD).
     
    4. The method of claim 3, wherein the first time interval (TU) and the second time interval (TD) are mutually exclusive time intervals; and/or
    wherein the first time interval (TU) occurs after the second time interval (TD).
     
    5. The method of claim 2, wherein the synchronous TDD uplink portion of the third frequency band occurs during the first time interval (TU); and/or
    the synchronous TDD downlink portion of the third frequency band occurs during the second time interval (TD).
     
    6. The method of claim 5, wherein the first portion (730) of the first frequency band has a larger frequency range than the second portion (732) of the first frequency band.
     
    7. The method of claims 5 or 6, wherein the FDD communication path in the second frequency band (722) comprises an FDD uplink path; and
    wherein the second portion (732) is separated from the second frequency band (722) by a downlink guard band (734).
     
    8. The method of claim 5, wherein the first portion (770) has a smaller frequency range than the second portion (772); and/or
    wherein the FDD communication path in the second frequency band (762) comprises an FDD downlink path.
     
    9. The method of claim 2, comprising:

    sending a third signal over the synchronous TDD path via the synchronous TDD uplink portion of the third frequency band (726, 766); and/or

    receiving a fourth signal over the synchronous TDD path via the synchronous TDD downlink portion of the third frequency band (726, 766).


     
    10. The method of claims 2 or 9, comprising:

    sending a fifth signal over the FDD communication path via the second frequency band (722);

    wherein:
    the fifth signal is sent over the FDD communication path during at least a portion of a time interval encompassing both the first time interval (TU) and the second time interval (TD).


     
    11. The method of claim 10, wherein the FDD communication path is separated by a downlink guard band (734) from the second portion (732) during the second time interval (TD);
    wherein the downlink guard band (734) has a bandwidth sufficient to limit interference between the second portion (732) and the second frequency band (722).
     
    12. The method of claims 2 or 9, comprising:

    receiving a sixth signal over the FDD communication path via the second frequency band (762);

    wherein:
    the sixth signal is sent over the FDD communication path during at least a portion of the time interval encompassing both the first time interval (TU) and the second time interval (TD).


     
    13. The method of claim 12, wherein the FDD communication path is separated by an uplink guard band (774) from the first portion (770) during the first time interval (TU); and/or
    wherein the uplink guard band (774) has a bandwidth sufficient to limit interference between the first portion (770) and the second frequency band (726).
     
    14. An apparatus comprising a communication device configured to::

    send a first signal via a first portion (730, 770) of a first frequency band (724, 764),

    receive a second signal via a second portion (732, 772) of the first frequency band (724, 764), wherein a bandwidth utilized by the second portion is different from a bandwidth utilized by the first portion,

    characterized by:

    the first frequency band (724, 764) is immediately adjacent to a second frequency band (722, 762),

    the first frequency band (724, 764) is immediately adjacent to a third frequency band (726, 766),

    the first frequency band (724, 764), the second frequency band (722, 762) and the third frequency band (726, 766) are mutually exclusive frequency bands,

    wherein:

    an asymmetric time division duplex (TDD) communication path is operable in the first frequency band (724, 764), wherein, for the asymmetric TDD communication path, a time-bandwidth product associated with the first portion (730, 770) of the first frequency band (724, 764) is different from the time-bandwidth product associated with the second portion (732, 772) of the first frequency band (724, 764),

    a frequency division duplex (FDD) communication path is operable in the second frequency band (722, 762),

    a synchronous TDD communication path that is synchronized to the TDD communication path in the first frequency band is operable in the third frequency band (726, 766);

    wherein:

    the first portion (730, 770) of the first frequency band (724, 764) occurs during a first time interval (TU),

    the second portion (732, 772) of the first frequency band (724, 764) occurs during a second time interval (TD), and

    wherein:

    a) the first portion (730) is contiguous with each of the second frequency band (722) and the third frequency band (726) during the first time interval (TU), and the second portion (732) is contiguous with only the third frequency band (726) during a second time interval (TD); the second portion (732) of the first frequency band (724) being separated from the third frequency band (726) by a first guard band (734) that is part of the first frequency band (724), wherein the first guard band (734) is located where the second portion (732) of the first frequency band (724) and the third frequency band (726) are transmitting or receiving signals in opposite directions; or

    b) the first portion (770) is contiguous with only the third frequency band (766) during the first time interval (TU) with a second guard band (774) being positioned between the first portion (770) of the first frequency band (764) and the second frequency band (762) and with the second guard band (774) being part of the first frequency band (764), wherein the second guard band (774) is located where the first portion (770) of the first frequency band (764) and the third frequency band (766) are transmitting or receiving signals in opposite directions, and the second portion (772) is contiguous with each of the second frequency band (762) and the third frequency band (766) during the second time interval (TD).


     


    Ansprüche

    1. Verfahren, umfassend:

    Senden eines ersten Signals über einen ersten Abschnitt (730, 770) eines ersten Frequenzbandes (724, 764),

    Empfangen eines zweiten Signals über einen zweiten Abschnitt (732, 772) des ersten Frequenzbandes (724, 764), wobei sich eine von dem zweiten Abschnitt verwendete Bandbreite von einer von dem ersten Abschnitt verwendeten Bandbreite unterscheidet,

    dadurch gekennzeichnet, dass:

    das erste Frequenzband (724, 764) unmittelbar an ein zweites Frequenzband (722, 762) angrenzt,

    das erste Frequenzband (724, 764) unmittelbar an ein drittes Frequenzband (726, 766) angrenzt,

    das erste Frequenzband (724, 764), das zweite Frequenzband (722, 762) und das dritte Frequenzband (726, 766) sich gegenseitig ausschließende Frequenzbänder sind,

    wobei:

    ein asymmetrischer Zeitduplex-(TDD)-Kommunikationspfad im ersten Frequenzband (724, 764) betreibbar ist, wobei für den asymmetrischen TDD-Kommunikationspfad ein dem ersten Abschnitt (730, 770) des ersten Frequenzbandes (724, 764) zugeordnetes Zeitbandbreitenprodukt sich von dem dem zweiten Abschnitt (732, 772) des ersten Frequenzbandes (724, 764) zugeordneten Zeitbandbreitenprodukt unterscheidet,

    ein Frequenzmultiplex-(FDD)-Kommunikationspfad in dem zweiten Frequenzband (722, 762) betreibbar ist,

    ein synchroner TDD-Kommunikationspfad, der mit dem TDD-Kommunikationspfad im ersten Frequenzband synchronisiert ist, in dem dritten Frequenzband (726, 766) betreibbar ist; und

    wobei:

    der erste Abschnitt (730, 770) des ersten Frequenzbandes (724, 764) während eines ersten Zeitintervalls (TU) auftritt,

    der zweite Abschnitt (732, 772) des ersten Frequenzbandes (724, 764) während eines zweiten Zeitintervalls (TD) auftritt, und

    wobei:

    a) der erste Abschnitt (730) während des ersten Zeitintervalls (TU) sowohl mit dem zweiten Frequenzband (722) als auch mit dem dritten Frequenzband (726) benachbart ist, und der zweite Abschnitt (732) während eines zweiten Zeitintervalls (TD) nur mit dem dritten Frequenzband (726) benachbart ist, wobei der zweite Abschnitt (732) des ersten Frequenzbandes (724) von dem dritten Frequenzband (726) durch ein erstes Schutzband (734) getrennt ist, das Teil des ersten Frequenzbandes (724) ist, wobei das erste Schutzband (734) dort angeordnet ist, wo der zweite Abschnitt (732) des ersten Frequenzbandes (724) und das dritte Frequenzband (726) Signale in entgegengesetzten Richtungen senden oder empfangen; oder

    b) der erste Abschnitt (770) während des ersten Zeitintervalls (TU) nur mit dem dritten Frequenzband (766) benachbart ist, wobei ein zweites Schutzband (774) zwischen dem ersten Abschnitt (770) des ersten Frequenzbandes (764) und dem zweiten Frequenzband (762) positioniert ist und wobei das zweite Schutzband (774) Teil des ersten Frequenzbandes (764) ist, wobei das zweite Schutzband (774) dort angeordnet ist, wo der erste Abschnitt (770) des ersten Frequenzbandes (764) und das dritte Frequenzband (766) Signale in entgegengesetzte Richtungen senden oder empfangen, und der zweite Abschnitt (772) während des zweiten Zeitintervalls (TD) mit sowohl dem zweiten Frequenzband (762) als auch dem dritten Frequenzband (766) verbunden ist.


     
    2. Verfahren nach Anspruch 1, wobei ein synchroner TDD-Aufwärtsstreckenabschnitt und ein synchroner TDD-Abwärtsstreckenabschnitt im dritten Frequenzband (726, 766) betreibbar sind.
     
    3. Verfahren nach Anspruch 1 oder 2, wobei das erste Zeitintervall (TU) die gleiche Dauer wie das zweite Zeitintervall (TD) aufweist.
     
    4. Verfahren nach Anspruch 3, wobei das erste Zeitintervall (TU) und das zweite Zeitintervall (TD) sich gegenseitig ausschließende Zeitintervalle sind; und/oder wobei das erste Zeitintervall (TU) nach dem zweiten Zeitintervall (TD) auftritt.
     
    5. Verfahren nach Anspruch 2, worin der synchrone TDD-Aufwärtsstreckenabschnitt des dritten Frequenzbandes während des ersten Zeitintervalls (TU) auftritt; und/oder der synchrone TDD- Abwärtsstreckenabschnitt des dritten Frequenzbandes während des zweiten Zeitintervalls (TD) auftritt.
     
    6. Verfahren nach Anspruch 5, wobei der erste Abschnitt (730) des ersten Frequenzbandes einen größeren Frequenzbereich aufweist als der zweite Abschnitt (732) des ersten Frequenzbandes.
     
    7. Verfahren nach Anspruch 5 oder 6, wobei der FDD-Kommunikationspfad im zweiten Frequenzband (722) einen FDD- Aufwärtsstreckenpfad aufweist; und
    wobei der zweite Abschnitt (732) von dem zweiten Frequenzband (722) durch ein Abwärtsstrecken-Schutzband (734) getrennt ist.
     
    8. Verfahren nach Anspruch 5, wobei der erste Abschnitt (770) einen kleineren Frequenzbereich aufweist als der zweite Abschnitt (772); und/oder wobei der FDD-Kommunikationspfad in dem zweiten Frequenzband (762) einen FDD-Abwärtsstreckenpfad aufweist.
     
    9. Das Verfahren nach Anspruch 2, umfassend:

    Senden eines dritten Signals über den synchronen TDD-Pfad über den synchronen TDD-Aufwärtsstreckenabschnitt des dritten Frequenzbandes (726, 766); und/oder

    Empfangen eines vierten Signals über den synchronen TDD-Pfad über den synchronen TDD- Abwärtsstreckenabschnitt des dritten Frequenzbandes (726, 766).


     
    10. Verfahren nach den Ansprüchen 2 oder 9, umfassend:

    Senden eines fünften Signals über den FDD-Kommunikationspfad über das zweite Frequenzband (722);

    wobei:
    das fünfte Signal über den FDD-Kommunikationspfad während mindestens eines Teils eines Zeitintervalls gesendet wird, das sowohl das erste Zeitintervall (TU) als auch das zweite Zeitintervall (TD) umfasst.


     
    11. Verfahren nach Anspruch 10, wobei der FDD-Kommunikationspfad während des zweiten Zeitintervalls (TD) durch ein Abwärtsstrecken-Schutzband (734) von dem zweiten Abschnitt (732) getrennt ist;
    wobei das Abwärtsstrecken-Schutzband (734) eine Bandbreite aufweist, die ausreicht, um Störungen zwischen dem zweiten Abschnitt (732) und dem zweiten Frequenzband (722) zu begrenzen.
     
    12. Verfahren nach den Ansprüchen 2 oder 9, umfassend:

    Empfangen eines sechsten Signals über den FDD-Kommunikationspfad über das zweite Frequenzband (762);

    wobei:
    das sechste Signal über den FDD-Kommunikationspfad während mindestens eines Teils des Zeitintervalls gesendet wird, das sowohl das erste Zeitintervall (TU) als auch das zweite Zeitintervall (TD) umfasst.


     
    13. Verfahren nach Anspruch 12, wobei der FDD-Kommunikationspfad während des ersten Zeitintervalls (TU) durch ein Aufwärtsstrecken-Schutzband (774) von dem ersten Abschnitt (770) getrennt ist; und/oder
    wobei das Aufwärtsstrecken-Schutzband (774) eine Bandbreite aufweist, die ausreicht, um Störungen zwischen dem ersten Abschnitt (770) und dem zweiten Frequenzband (726) zu begrenzen.
     
    14. Eine Vorrichtung, die eine Kommunikationsvorrichtung umfasst, die konfiguriert ist zum:

    Senden eines ersten Signals über einen ersten Abschnitt (730, 770) eines ersten Frequenzbandes (724, 764),

    Empfangen eines zweiten Signals über einen zweiten Abschnitt (732, 772) des ersten Frequenzbandes (724, 764), wobei sich eine von dem zweiten Abschnitt verwendete Bandbreite von einer von dem ersten Abschnitt verwendeten Bandbreite unterscheidet,

    dadurch gekennzeichnet, dass:

    das erste Frequenzband (724, 764) unmittelbar an ein zweites Frequenzband (722, 762) angrenzt,

    das erste Frequenzband (724, 764) unmittelbar an ein drittes Frequenzband (726, 766) angrenzt,

    das erste Frequenzband (724, 764), das zweite Frequenzband (722, 762) und das dritte Frequenzband (726, 766) sich gegenseitig ausschließende Frequenzbänder sind,

    wobei:

    ein asymmetrischer Zeitduplex-(TDD)-Kommunikationspfad im ersten Frequenzband (724, 764) betreibbar ist, wobei für den asymmetrischen TDD-Kommunikationspfad ein dem ersten Abschnitt (730, 770) des ersten Frequenzbandes (724, 764) zugeordnetes Zeitbandbreitenprodukt sich von dem dem zweiten Abschnitt (732, 772) des ersten Frequenzbandes (724, 764) zugeordneten Zeitbandbreitenprodukt unterscheidet,

    ein Frequenzmultiplex-(FDD)-Kommunikationspfad im zweiten Frequenzband (722, 762) betreibbar ist,

    ein synchroner TDD-Kommunikationspfad, der mit dem TDD-Kommunikationspfad im ersten Frequenzband synchronisiert ist, im dritten Frequenzband (726, 766) betreibbar ist;

    wobei:

    der erste Abschnitt (730, 770) des ersten Frequenzbandes (724, 764) während eines ersten Zeitintervalls (TU) auftritt,

    der zweite Abschnitt (732, 772) des ersten Frequenzbandes (724, 764) während eines zweiten Zeitintervalls (TD) auftritt, und

    wobei:

    a) der erste Abschnitt (730) während des ersten Zeitintervalls (TU) sowohl mit dem zweiten Frequenzband (722) als auch dem dritten Frequenzband (726) benachbart ist, und der zweite Abschnitt (732) während eines zweiten Zeitintervalls (TD) nur mit dem dritten Frequenzband (726) benachbart ist, wobei der zweite Abschnitt (732) des ersten Frequenzbandes (724) von dem dritten Frequenzband (726) durch ein erstes Schutzband (734) getrennt ist, das Teil des ersten Frequenzbandes (724) ist, wobei das erste Schutzband (734) dort angeordnet ist, wo der zweite Abschnitt (732) des ersten Frequenzbandes (724) und das dritte Frequenzband (726) Signale in entgegengesetzten Richtungen senden oder empfangen; oder

    b) der erste Abschnitt (770) während des ersten Zeitintervalls (TU) nur mit dem dritten Frequenzband (766) benachbart ist, wobei ein zweites Schutzband (774) zwischen dem ersten Abschnitt (770) des ersten Frequenzbandes (764) und dem zweiten Frequenzband (762) positioniert ist und wobei das zweite Schutzband (774) Teil des ersten Frequenzbandes (764) ist, wobei das zweite Schutzband (774) dort angeordnet ist, wo der erste Abschnitt (770) des ersten Frequenzbandes (764) und das dritte Frequenzband (766) Signale in entgegengesetzte Richtungen senden oder empfangen, und der zweite Abschnitt (772) sowohl mit dem zweiten Frequenzband (762) als auch dem dritten Frequenzband (766) während des zweiten Zeitintervalls (TD) benachbart ist.


     


    Revendications

    1. Procédé, comprenant:

    envoyer un premier signal via une première partie (730, 770) d'une première bande de fréquences (724, 764),

    recevoir un second signal via une seconde partie (732, 772) de la première bande de fréquences (724, 764), dans laquelle une largeur de bande utilisée par la seconde partie est différente d'une largeur de bande utilisée par la première partie,

    caractérisé par:

    la première bande de fréquences (724, 764) étant immédiatement adjacente à une seconde bande de fréquences (722, 762),

    la première bande de fréquences (724, 764) étant immédiatement adjacente à une troisième bande de fréquences (726, 766),

    la première bande de fréquences (724, 764), la deuxième bande de fréquences (722, 762) et la troisième bande de fréquences (726, 766) étant mutuellement exclusives,

    dans laquelle:

    une trajet de communication duplex à répartition dans le temps (TDD) asymétrique est utilisable dans la première bande de fréquences (724, 764), dans laquelle, pour la trajet de communication TDD asymétrique, un produit de largeur de bande de temps associé à la première partie (730, 770) de la première bande de fréquences (724, 764) est différent du produit de largeur de bande dans le temps associé à la seconde partie (732, 772) de la première bande de fréquences (724, 764),

    une trajet de communication duplex à répartition en fréquence (FDD) est utilisable dans la deuxième bande de fréquences (722, 762),

    un trajet de communication DRT synchrone qui est synchronisé avec le trajet de communication DRT dans la première bande de fréquences est utilisable dans la troisième bande de fréquences (726, 766); et

    dans laquelle:

    la première partie (730, 770) de la première bande de fréquences (724, 764) se produit pendant un premier intervalle de temps (TU),

    la deuxième partie (732, 772) de la première bande de fréquences (724, 764) se produit pendant un deuxième intervalle de temps (TD), et

    dans laquelle :

    a) la première partie (730) est contiguë à chacune de la deuxième bande de fréquences (722) et de la troisième bande de fréquences (726) pendant le premier intervalle de temps (TU), et la deuxième partie (732) est contiguë à seulement la troisième bande de fréquences (726) pendant un deuxième intervalle de temps (TD), la seconde partie (732) de la première bande de fréquences (724) étant séparée de la troisième bande de fréquences (726) par une première bande de garde (734) qui fait partie de la première bande de fréquences (724), dans laquelle la première bande de garde (734) est située où la seconde partie (732) de la première bande de fréquences (724) et la troisième bande de fréquences (726) sont des signaux émis ou reçus en direction opposée ; ou

    b) la première partie (770) est contiguë à seulement la troisième bande de fréquences (766) pendant le premier intervalle de temps (TU), une deuxième bande de garde (774) étant positionnée entre la première partie (770) de la première bande de fréquences (764) et la deuxième bande de fréquences (762) et la deuxième bande de garde (774) étant partie de la première bande de fréquences (764), dans laquelle la seconde bande de garde (774) est située là où la première partie (770) de la première bande de fréquences (764) et la troisième bande de fréquences (766) émettent ou reçoivent des signaux dans des directions opposées, et la seconde partie (772) est contiguë à chacune de la seconde bande de fréquences (762) et de la troisième bande de fréquences (766) durant le deuxième intervalle de temps (TD).


     
    2. Procédé selon la revendication 1, dans lequel une partie synchrone de liaison montante DRT et une partie synchrone de liaison descendante DRT fonctionnent dans la troisième bande de fréquences (726, 766).
     
    3. Procédé de revendications 1 ou 2, dans lequel le premier intervalle de temps (TU) a la même durée que le second intervalle de temps (TD).
     
    4. Procédé selon la revendication 3, dans lequel le premier intervalle de temps (TU) et le second intervalle de temps (TD) sont des intervalles de temps mutuellement exclusifs ;
    et/ou
    dans laquelle le premier intervalle de temps (TU) se produit après le second intervalle de temps (TD).
     
    5. procédé selon la revendication 2, dans lequel la partie synchrone de liaison montante DRT de la troisième bande de fréquences se produit pendant le premier intervalle de temps (TU) ; et/ou
    la partie synchrone de la liaison descendante DRT de la troisième bande de fréquences se produit pendant le deuxième intervalle de temps (TD).
     
    6. Procédé selon la revendication 5, dans lequel la première partie (730) de la première bande de fréquences a une gamme de fréquences plus large que la seconde partie (732) de la première bande de fréquences.
     
    7. Procédé selon les revendications 5 ou 6, dans lequel le trajet de communication FDD dans la seconde bande de fréquences (722) comprend un trajet de liaison montante FDD;
    et
    dans laquelle la seconde partie (732) est séparée de la seconde bande de fréquences (722) par une bande de garde de liaison descendante (734).
     
    8. Procédé selon la revendication 5, dans lequel la première partie (770) a une gamme de fréquences plus petite que la seconde partie (772); et/ou
    dans laquelle le trajet de communication FDD dans la seconde bande de fréquences (762) comprend un trajet de liaison descendante FDD.
     
    9. Le procédé de la revendication 2, comprenant :

    l'envoi d'un troisième signal sur le trajet DRT synchrone via la partie synchrone de la liaison montante DRT de la troisième bande de fréquences (726, 766); et/ou

    recevoir un quatrième signal sur le trajet DRT synchrone via la partie synchrone de la liaison descendante DRT de la troisième bande de fréquences (726, 766).


     
    10. Procédé de revendication 2 ou 9, comprenant :

    l'envoi d'un cinquième signal sur le trajet de communication FDD via la deuxième bande de fréquences (722);

    dans laquelle:
    le cinquième signal est envoyé sur le trajet de communication FDD pendant au moins une partie d'un intervalle de temps englobant à la fois le premier intervalle de temps (TU) et le second intervalle de temps (TD).


     
    11. Procédé selon la revendication 10, dans lequel le trajet de communication FDD est séparé par une bande de garde de liaison descendante (734) de la seconde partie (732) pendant le second intervalle de temps (TD);
    dans laquelle la bande de garde de liaison descendante (734) a une largeur de bande suffisante pour limiter l'interférence entre la seconde partie (732) et la seconde bande de fréquence (722).
     
    12. Procédé de revendication 2 ou 9, comprenant:

    la réception d'un sixième signal sur le trajet de communication FDD via la deuxième bande de fréquences (762) ;

    dans laquelle:
    le sixième signal est envoyé sur le trajet de communication FDD pendant au moins une partie de l'intervalle de temps englobant à la fois le premier intervalle de temps (TU) et le second intervalle de temps (TD).


     
    13. Procédé selon la revendication 12, dans lequel le trajet de communication FDD est séparé par une bande de garde de liaison montante (774) de la première partie (770) pendant le premier intervalle de temps (TU); et/ou
    dans laquelle la bande de garde de liaison montante (774) a une largeur de bande suffisante pour limiter l'interférence entre la première partie (770) et la seconde bande de fréquence (726).
     
    14. Appareil comprenant un dispositif de communication configuré pour:

    envoyer un premier signal via une première partie (730, 770) d'une première bande de fréquences (724, 764),

    recevoir un second signal via une seconde partie (732, 772) de la première bande de fréquences (724, 764), dans laquelle une largeur de bande utilisée par la seconde partie est différente de celle utilisée par la première partie,

    caractérisé par:

    la première bande de fréquences (724, 764) est immédiatement adjacente à une seconde bande de fréquences (722, 762),

    la première bande de fréquences (724, 764) est immédiatement adjacente à une troisième bande de fréquences (726, 766),

    la première bande de fréquences (724, 764), la deuxième bande de fréquences (722, 762) et la troisième bande de fréquences (726, 766) sont mutuellement exclusives,

    dans laquelle:

    une trajet de communication duplex à répartition dans le temps (TDD) asymétrique est utilisable dans la première bande de fréquences (724, 764), dans laquelle, pour la trajet de communication TDD asymétrique, un produit de largeur de bande de temps associé à la première partie (730, 770) de la première bande de fréquences (724, 764) est différent du produit de largeur de bande dans le temps associé à la seconde partie (732, 772) de la première bande de fréquences (724, 764),

    une trajet de communication duplex à répartition en fréquence (FDD) est utilisable dans la deuxième bande de fréquences (722, 762),

    un trajet de communication DRT synchrone qui est synchronisé avec le trajet de communication DRT dans la première bande de fréquences est utilisable dans la troisième bande de fréquences (726, 766) ;

    dans laquelle:

    la première partie (730, 770) de la première bande de fréquences (724, 764) se produit pendant un premier intervalle de temps (TU),

    la deuxième partie (732, 772) de la première bande de fréquences (724, 764) se produit pendant un deuxième intervalle de temps (TD), et

    dans laquelle:

    a) la première partie (730) est contiguë à chacune de la deuxième bande de fréquences (722) et de la troisième bande de fréquences (726) pendant le premier intervalle de temps (TU), et la deuxième partie (732) est contiguë à seulement la troisième bande de fréquences (726) pendant un deuxième intervalle de temps (TD), la seconde partie (732) de la première bande de fréquences (724) étant séparée de la troisième bande de fréquences (726) par une première bande de garde (734) qui fait partie de la première bande de fréquences (724), dans laquelle la première bande de garde (734) est située où la seconde partie (732) de la première bande de fréquences (724) et la troisième bande de fréquences (726) sont des signaux émis ou reçus en direction opposée ; ou

    b) la première partie (770) est contiguë à seulement la troisième bande de fréquences (766) pendant le premier intervalle de temps (TU), une deuxième bande de garde (774) étant positionnée entre la première partie (770) de la première bande de fréquences (764) et la deuxième bande de fréquences (762) et la deuxième bande de garde (774) étant partie de la première bande de fréquences (764), dans laquelle la seconde bande de garde (774) est située là où la première partie (770) de la première bande de fréquences (764) et la troisième bande de fréquences (766) émettent ou reçoivent des signaux dans des directions opposées, et la seconde partie (772) est contiguë à chacune de la seconde bande de fréquences (762) et de la troisième bande de fréquences (766) durant le deuxième intervalle de temps (TD).


     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description