FIELD
[0001] The present application generally relates to an antenna and, in particular, to an
antenna integrated with an electrostatic discharge protection shield and devices that
include an antenna integrated with an electrostatic discharge protection shield.
BACKGROUND
[0002] As consumer electronics devices become more compact and achieve greater functionality,
it has become increasingly difficult to arrange the interior components to realize
higher density. This is especially so with wireless communications devices, including
handheld devices, personal digital assistants, mobile smartphones, etc., where the
devices are increasingly compact, yet include a greater number of components and features
than ever before. Many such devices now include keyboards, cameras, trackballs, display
screens (ordinary or touchscreen), memory cards, speakers, microphones, I/O jacks,
and multiple antennas, for cellular, IEEE 802.11, Bluetooth®, GPS, and other radio
frequency communications. This has made the configuration of the components challenging
and puts circuit board space at a premium.
[0003] It would be advantageous to provide for an electronic device having a new configuration
of components that permits greater density.
SUMMARY
[0004] The present application describes an antenna partly formed from the electrostatic
discharge shield covering a microphone in an electronic device. By exploiting the
presence of the electrostatic discharge shield and using it as the shorting element
in the antenna, space is saved. Moreover, to the extent the microphone employs an
acoustic tube to form an acoustic pathway between the device casing and the microphone,
the radiator arm of the antenna integrally formed with the electrostatic discharge
shield may be arranged over the acoustic tube, which results in an efficient arrangement
of elements.
[0005] In one aspect, the present application describes a handheld electronic device. The
device includes a substrate having a ground plane and an antenna signal trace; a microphone
mounted to the substrate; a metallic shield disposed over the microphone and being
connected to the ground plane; and a radio frequency antenna formed in part from the
metallic shield and having at least one radiator arm connected to the metallic shield.
The antenna includes a feed point connected to the antenna signal trace.
[0006] In another aspect, the present application describes a mobile communications device.
The device includes a device casing having an acoustic microphone opening; a substrate
within the device casing, the substrate having an electrical ground and a signal trace;
a microphone mounted to the substrate; an electrostatic discharge shield disposed
over the microphone and connected to the electrical ground, the electrostatic discharge
shield defining an acoustic port; and an antenna having a radiator arm and a feed
element both connected to the electrostatic discharge shield, and wherein the feed
element is further connected to the signal trace.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Reference will now be made, by way of example, to the accompanying drawings which
show example embodiments of the present application, and in which:
[0008] Figure 1 shows a side view of one embodiment of an antenna integrated with ESD protection;
[0009] Figure 2 shows a top planar view of the antenna of Figure 1;
[0010] Figure 3 shows a front view of the antenna of Figure 1;
[0011] Figure 4 shows a perspective view of the antenna of Figure 1;
[0012] Figure 5 shows a perspective view of an example embodiment of an acoustic shield
for use with the microphone;
[0013] Figure 6 shows a block diagram of the antenna;
[0014] Figures 7 through 11 show additional example embodiments of the antenna; and
[0015] Figure 12 shows a block diagram of a handheld electronic device incorporating the
antenna.
[0016] Similar reference numerals may have been used in different figures to denote similar
components.
DESCRIPTION OF EXAMPLE EMBODIMENTS
[0017] Many electronics devices include an antenna for radio frequency communications, including
mobile devices, laptop computers, desktop computers, smartphones, personal digital
assistants, and many other such devices. Many of these devices also include a microphone
that functions to receive audio input and convert the audio to electrical signals
that are processed by the device. In many cases, the microphone serves to permit voice
communications, such as in a mobile telephone and other devices configured for wireless
communications.
[0018] Microphones are transducers that require exposure to the environment in order to
receive acoustic signals. The environment can also have a detrimental impact on microphones,
as they become exposed to environmental hazards such as human liquids or oils. Accordingly,
in some cases microphones are encased in a sealed rubber covering, except for an opening
(i.e. a port or hole) through which acoustic waves are to be received. A gasket or
"rubber boots" may be used to seal the port or hole to the exterior casing of the
electronic device.
[0019] Microphones and their associated coder/decoder (CODEC) integrated circuits (ICs)
are also vulnerable to electrostatic discharge (ESD). Techniques that have been developed
for protecting microphones from electrostatic discharge include covering the microphone
(except the acoustic opening/port) with a grounded casing or shield. Alternatively
or additionally, transient voltage suppressor (TVS) diodes may be added to the microphone
circuit to absorb ESD events. Adding TVS diodes can be costly and may negatively impact
the performance of the audio circuits.
[0020] Reference is now made to Figure 1, which shows a side view of one embodiment of an
antenna 10 integrated with ESD protection. The antenna 10 is formed partly with an
ESD shield (generally 14) over a microphone 12. The microphone 12 is illustrated in
phantom lines. The microphone 12 is mounted or connected to a printed circuit board
16 or other substrate. In this application, the term "substrate" is intended to encompass
printed circuit boards and any other such substrate on which electrical components
may be assembled and interconnected to form an electronic device. The printed circuit
board 16 includes a ground connection or plane (not illustrated). The microphone 12
is connected to suitable audio circuitry and a CODEC IC for receiving and processing
signals from the microphone 12. In one embodiment, the microphone 12 is an Electret
Condenser Microphone (ECM), however in other embodiments other types of microphones
may be used.
[0021] A top plan view of the antenna 10 is shown in Figure 2. Figure 3 shows a front view
of the antenna 10, and Figure 4 shows a perspective view.
[0022] The microphone 12 is protected from ESD events by the ESD shield 14. The ESD shield
14 is a metal covering or casing connected to a ground plane or trace on the circuit
board 16. In Figures 1-4 the microphone 12 is shown as a cylindrical element for ease
of illustration. Those skilled in the art will appreciate that the microphone 12 is
not necessarily cylindrical and is not necessarily arranged on the circuit board 16
in the manner illustrated in Figures 1-4.
[0023] The ESD shield 14 generally covers the microphone 12, and, in the illustrated embodiment,
has a top section 20, and side sections 22, 24. At the front of the ESD shield 14,
the side sections 22, 24 are separated to define an acoustic opening or port 26 through
which the microphone 12 may receive acoustic waves. The interior of the ESD shield
14 creates an acoustic cavity. At least one of the side sections 22, 24 is connected
to electrical ground. For example, one or both of the side sections 22, 24 may be
directly connected to a ground plane on or within the printed circuit board 16 or
substrate to which the microphone 12 is mounted. Because the ESD shield 14 is grounded,
it protects the microphone 12 from spurious ESD events and from electromagnetic interference.
In many embodiments, this may eliminate the need for TVS diode protection, which may
reduce the cost associated with the microphone 12.
[0024] Reference is now made to Figure 5, which shows a perspective view of an example embodiment
of an acoustic shield 30 for use with the microphone 12. The acoustic shield 30 is
intended to shield the microphone 12 from unwanted acoustic interference and/or reflections
but permit desired voice range acoustic waves to be received through the acoustic
port 26.
[0025] The acoustic shield 30 includes a non-metal acoustic tube 32 for connecting the acoustic
port 26 to the casing of the electronic device (not shown). The acoustic tube 32 is
formed from rubber or other suitable material. The acoustic tube 32 provides a pathway
34 for acoustic waves to travel from a port or opening in the exterior casing of the
device to the acoustic port 26 in the ESD shield 14. Although the tube 32 is straight
in many embodiments, in some embodiments it may be possible for the tube 32 to have
bends or curves provided that its interior dimensions and angles permit a reasonably
efficient transfer of sound in the voice range down the pathway 34 of the tube 32.
The end of the tube 32 at the casing may be sealed to the casing.
[0026] In some embodiments the acoustic shield 30 includes a cavity portion 36 sized to
fit within the ESD shield 14 and substantially surround the microphone 12. It will
be appreciated that the cavity portion 36 does not pass underneath the microphone
12 where the microphone 12 is attached to the circuit board 16, but rather fits on
top of the microphone 12. The interior of the cavity portion 36 is dimensioned so
that the tube resonance is above the audio band used in telephony.
[0027] The interior of the cavity portion 36 is in sealed communication with the pathway
34 of the tube 32 to permit sound transfer down the pathway 34 to the interior of
the cavity portion 36 and, thus, the microphone 12. The cavity portion 36 may otherwise
have a sidewall 38 and top wall 40 that substantially surrounds the microphone 12.
[0028] Those ordinarily skilled in the art will appreciate the range of suitable materials
that may be employed to create the acoustic shield 30.
[0029] Referring still to Figures 1 to 5, the antenna 10 includes a radiator arm 50 and
a feed element 52. The radiator arm 50 is, in this embodiment, a metal planar element.
The radiator arm 50 may, in some embodiments, be formed integrally with the ESD shield
14. In this particular embodiment, the radiator arm 50 lies in the same plane as the
top section 20 of the ESD shield 14. The feed element 52 is a metal element connected
to approximately the opposite side of the top section 20 from the radiator arm 50.
The feed element 52 extends down to the circuit board 16 or other substrate where
it connects to a signal trace or other circuit element through which it may electrically
conduct received or transmitted signals. In the embodiment shown in Figures 1-4, the
feed element 52 extends downwards at an acute angle; however, in other embodiments
it may extend downwards perpendicular to the top section 20.
[0030] The radiator arm 50 may be arranged to extend partly or wholly above the acoustic
tube 32 (Fig. 5). In some embodiments the radiator arm 50 may be wider, thinner or
the same width as the acoustic tube 32. In some embodiments the radiator arm 50 is
the same or shorter than the length of the acoustic tube 32. The length and width
of the radiator arm 50 are selected in conjunction with the dimensions of the top
section 20 and the feed element 52 to give the antenna 10 the desired RF properties.
The length and width of the radiator arm 50 may be selected so as to frequency tune
the antenna 10.
[0031] The radiator arm 50, ESD shield 14, and feed element 52 are, in one embodiment, formed
from a metal stamping process.
[0032] Reference is now also made to Figure 6, which shows a block diagram of the antenna
10. The antenna 10 is formed from the radiator arm 50, the grounded ESD shield 14,
and feed element 52. The ESD shield 14, in particular the top section 20, serves as
a shorted element of the antenna 10. Either one of the sides 22, 24 of the ESD shield
14 or both sides 22, 24 may be connected to ground. The feed element 52 is connected
to a signal trace or circuit element connected to a matching block 60. The matching
circuit 60 is configured to impedance match with the antenna 10, as will be understood
by those skilled in the art. The matching circuit 60 may, in some embodiments, be
implemented using integrated passive devices (IPDs).
[0033] The feed element 52 is coupled to a signal source 62 through the matching circuit
60. The signal source 62 is configured to drive the antenna 10 at one or more frequencies
to which the antenna 10 is tuned. Those ordinarily skilled in the art will appreciate
the range of circuit elements and variations on configuration for using an RF antenna
such as the antenna 10 for sending or receiving RF signals.
[0034] It will be appreciated that the antenna 10 shown in Figures 6 and in Figures 1-4
is configured as an Inverted-F antenna. In other embodiments other microstrip antennas
may be implemented. It will be understood that the antenna 10 discussed herein is
an example only. Other embodiments of antennas integrated with the ESD shield of a
microphone may include multiple feed points, multiple shorting elements, slots, or
parasitic elements. It will also be understood that the radiator arm 50 may, in some
embodiments, be folded and/or non-planar. For example, the radiator arm 50 may be
arranged as a folded three-dimensional structure. In one embodiment, the radiator
arm 50 may have elements arranged along one or more of the sides of the acoustic tube
32.
[0035] Reference will now be made to Figures 7 through 11, which illustrate other example
embodiments of the antenna 10.
[0036] Figure 7 shows a perspective view of an embodiment of the antenna 10 with a non-cylindrical
ESD shield 114. In this embodiment, the ESD shield 114 is rectangular. In other embodiments,
the ESD shield 114 may be arranged in other shapes.
[0037] Figure 8 shows a perspective view of an embodiment of the antenna 10 with an ESD
shield 314 having the same width as the radiator arm 50. In this embodiment, the top
section 320 of the ESD shield 314 has the same width as the radiator arm and is generally
rectangular in shape. The sides 322, 324 of the ESD shield 314 extend downwards from
the top section 320 and the acoustic opening or port 326 occupies the entire front
of the ESD shield 314.
[0038] Figure 9 shows a right front perspective view of yet another embodiment of the antenna
10. In this embodiment, the ESD shield 14 is cylindrical, like in Figures 1-4; however,
the feed element 152 in this embodiment extends perpendicular to the top portion 20.
Gaps 154, 156 between the feed element 152 and the sides of the ESD shield 14 prevent
the feed element 152 from being shorted out in this embodiment.
[0039] Figure 10 illustrates an embodiment of the antenna 10 of Figures 1-4 arranged together
with the acoustic tube 32 of Figure 5. The acoustic tube 32 is shown in dashed lines
for ease of illustration. In this embodiment, the radiator arm 52 substantially covers
the top of the acoustic tube 32 and has nearly the same length as the acoustic tube
32.
[0040] Figure 11 shows another embodiment of the antenna 10 together with the acoustic tube
32. In this embodiment, the radiator arm 150 is formed as a folded three-dimensional
structure. The radiator arm 50 features portions on the top of the acoustic tube 32
and interconnecting portions on one or more of the sides of the acoustic tube 32,
so as to form a winding or switchback pattern in three-dimensions.
[0041] In the foregoing embodiments, the radiator arm 50 is shown lying in the same plane
as the top section 20 of the ESD shield 14. In other embodiments, the radiator arm
50 may extend in a different plane from the top section 20. As noted in connection
with Figure 11, the radiator arm 50 may have a three-dimensional shape. In addition,
although the top section 20 is illustrated as being planar in many of the embodiments,
in some embodiments the top section 20 may not be planar.
[0042] Those ordinarily skilled in the art will appreciated that the foregoing embodiments
are examples only and that many other configurations or shapes may be used to form
the ESD shield, radiator arm, and/or feed element of the antenna, depending on the
application desired.
[0043] Reference is now made to Figure 12, which shows an example embodiment of a mobile
communication device 201 which may incorporate the antenna 10 described herein. The
mobile communication device 201 is a two-way communication device having voice and
possibly data communication capabilities; for example, the capability to communicate
with other computer systems, e.g., via the Internet. Depending on the functionality
provided by the mobile communication device 201, in various embodiments the device
may be a multiple-mode communication device configured for both data and voice communication,
a smartphone, a mobile telephone or a PDA (personal digital assistant) enabled for
wireless communication, or a computer system with a wireless modem.
[0044] The mobile communication device 201 includes a controller comprising at least one
processor 240 such as a microprocessor which controls the overall operation of the
mobile communication device 201, and a wireless communication subsystem 211 for exchanging
radio frequency signals with the wireless network 101. The processor 240 interacts
with the communication subsystem 211 which performs communication functions. The processor
240 interacts with additional device subsystems. In some embodiments, the device 201
may include a touchscreen display 210 which includes a display (screen) 204, such
as a liquid crystal display (LCD) screen, with a touch-sensitive input surface or
overlay 206 connected to an electronic controller 208. The touch-sensitive overlay
206 and the electronic controller 208 provide a touch-sensitive input device and the
processor 240 interacts with the touch-sensitive overlay 206 via the electronic controller
208. In other embodiments, the display 204 may not be a touchscreen display. Instead,
the device 201 may simply include a non-touch display and one or more input mechanisms,
such as, for example, a depressible scroll wheel.
[0045] The processor 240 interacts with additional device subsystems including flash memory
244, random access memory (RAM) 246, read only memory (ROM) 248, auxiliary input/output
(I/O) subsystems 250, data port 252 such as serial data port, such as a Universal
Serial Bus (USB) data port, speaker 256, microphone 258, input mechanism 260, switch
261, short-range communication subsystem 272, and other device subsystems generally
designated as 274. Some of the subsystems shown in Figure 12 perform communication-related
functions, whereas other subsystems may provide "resident" or on-device functions.
[0046] The communication subsystem 211 may include a receiver, a transmitter, and associated
components, such as one or more antenna elements 10, local oscillators (LOs), and
a processing module such as a digital signal processor (DSP). The antenna 10 may be
embedded or internal to the mobile communication device 201 and a single antenna may
be shared by both receiver and transmitter, as is known in the art. As will be apparent
to those skilled in the field of communication, the particular design of the communication
subsystem 211 depends on the wireless network 101 in which the mobile communication
device 201 is intended to operate. As described above, the antenna 10 may be formed
integral with the microphone 258 ESD protection.
[0047] The mobile communication device 201 may communicate with any one of a plurality of
fixed transceiver base stations of a wireless network 101 within its geographic coverage
area. The mobile communication device 201 may send and receive communication signals
over the wireless network 101 after a network registration or activation procedures
have been completed. Signals received by the antenna 10 through the wireless network
101 are input to the receiver, which may perform such common receiver functions as
signal amplification, frequency down conversion, filtering, channel selection, etc.,
as well as analog-to-digital (A/D) conversion. A/D conversion of a received signal
allows more complex communication functions such as demodulation and decoding to be
performed in the DSP. In a similar manner, signals to be transmitted are processed,
including modulation and encoding, for example, by the DSP. These DSP-processed signals
are input to the transmitter for digital-to-analog (D/A) conversion, frequency up
conversion, filtering, amplification, and transmission to the wireless network 101
via the antenna 10.
[0048] The processor 240 operates under stored program control and executes software modules
220 stored in memory such as persistent memory, for example, in the flash memory 244.
As illustrated in Figure 12, the software modules 220 comprise operating system software
222 and software applications 224.
[0049] Those skilled in the art will appreciate that the software modules 220 or parts thereof
may be temporarily loaded into volatile memory such as the RAM 246. The RAM 246 is
used for storing runtime data variables and other types of data or information, as
will be apparent to those skilled in the art. Although specific functions are described
for various types of memory, this is merely one example, and those skilled in the
art will appreciate that a different assignment of functions to types of memory could
also be used.
[0050] The software applications 224 may include a range of other applications, including,
for example, a messaging application, a calendar application, and/or a notepad application.
In some embodiments, the software applications 224 include an email message application,
a push content viewing application, a voice communication (i.e. telephony) application,
a map application, and a media player application. Each of the software applications
224 may include layout information defining the placement of particular fields and
graphic elements (e.g. text fields, input fields, icons, etc.) in the user interface
(i.e. the display device 204) according to the application.
[0051] In some embodiments, the auxiliary input/output (I/O) subsystems 250 may comprise
an external communication link or interface, for example, an Ethernet connection.
The mobile communication device 201 may comprise other wireless communication interfaces
for communicating with other types of wireless networks, for example, a wireless network
such as an orthogonal frequency division multiplexed (OFDM) network or a GPS transceiver
for communicating with a GPS satellite network (not shown). The auxiliary I/O subsystems
250 may comprise a vibrator for providing vibratory notifications in response to various
events on the mobile communication device 201 such as receipt of an electronic communication
or incoming phone call, or for other purposes such as haptic feedback (touch feedback).
[0052] In some embodiments, the mobile communication device 201 also includes a removable
memory card 230 (typically comprising flash memory) and a memory card interface 232.
Network access may be associated with a subscriber or user of the mobile communication
device 201 via the memory card 230, which may be a Subscriber Identity Module (SIM)
card for use in a GSM network or other type of memory card for use in the relevant
wireless network type. The memory card 230 is inserted in or connected to the memory
card interface 232 of the mobile communication device 201 in order to operate in conjunction
with the wireless network 101.
[0053] The mobile communication device 201 stores data 240 in an erasable persistent memory,
which in one example embodiment is the flash memory 244. In various embodiments, the
data 240 includes service data comprising information required by the mobile communication
device 201 to establish and maintain communication with the wireless network 101.
The data 240 may also include user application data such as email messages, address
book and contact information, calendar and schedule information, notepad documents,
image files, and other commonly stored user information stored on the mobile communication
device 201 by its user, and other data. The data 240 stored in the persistent memory
(e.g. flash memory 244) of the mobile communication device 201 may be organized, at
least partially, into a number of databases each containing data items of the same
data type or associated with the same application.
[0054] The serial data port 252 may be used for synchronization with a user's host computer
system (not shown). The serial data port 252 enables a user to set preferences through
an external device or software application and extends the capabilities of the mobile
communication device 201 by providing for information or software downloads to the
mobile communication device 201 other than through the wireless network 101. The alternate
download path may, for example, be used to load an encryption key onto the mobile
communication device 201 through a direct, reliable and trusted connection to thereby
provide secure device communication.
[0055] In some embodiments, the mobile communication device 201 is provided with a service
routing application programming interface (API) which provides an application with
the ability to route traffic through a serial data (i.e., USB) or Bluetooth® (Bluetooth®
is a registered trademark of Bluetooth SIG, Inc.) connection to the host computer
system using standard connectivity protocols. When a user connects their mobile communication
device 201 to the host computer system via a USB cable or Bluetooth® connection, traffic
that was destined for the wireless network 101 is automatically routed to the mobile
communication device 201 using the USB cable or Bluetooth® connection. Similarly,
any traffic destined for the wireless network 101 is automatically sent over the USB
cable Bluetooth® connection to the host computer system for processing.
[0056] The mobile communication device 201 also includes a battery 238 as a power source,
which is typically one or more rechargeable batteries that may be charged, for example,
through charging circuitry coupled to a battery interface such as the serial data
port 252. The battery 238 provides electrical power to at least some of the electrical
circuitry in the mobile communication device 201, and the battery interface 236 provides
a mechanical and electrical connection for the battery 238. The battery interface
236 is coupled to a regulator (not shown) which provides power V+ to the circuitry
of the mobile communication device 201.
[0057] The short-range communication subsystem 272 is an additional optional component which
provides for communication between the mobile communication device 201 and different
systems or devices, which need not necessarily be similar devices. For example, the
subsystem 272 may include an infrared device and associated circuits and components,
or a wireless bus protocol compliant communication mechanism such as a Bluetooth®
communication module to provide for communication with similarly-enabled systems and
devices.
[0058] A predetermined set of applications that control basic device operations, including
data and possibly voice communication applications will normally be installed on the
mobile communication device 201 during or after manufacture. Additional applications
and/or upgrades to the operating system 221 or software applications 224 may also
be loaded onto the mobile communication device 201 through the wireless network 101,
the auxiliary I/O subsystem 250, the serial port 252, the short-range communication
subsystem 272, or other suitable subsystem 274 other wireless communication interfaces.
The downloaded programs or code modules may be permanently installed, for example,
written into the program memory (i.e. the flash memory 244), or written into and executed
from the RAM 246 for execution by the processor 240 at runtime. Such flexibility in
application installation increases the functionality of the mobile communication device
201 and may provide enhanced on-device functions, communication-related functions,
or both. For example, secure communication applications may enable electronic commerce
functions and other such financial transactions to be performed using the mobile communication
device 201.
[0059] Although in this embodiment, it is the communication subsystem 211 that employs the
antenna 10 integrated with the microphone 258 ESD protection, in other embodiments
a different communication system within the mobile device 201 may use an antenna integrated
with the microphone 258 ESD protection, such as a GPS system, or the short-range communication
subsystem 272.
[0060] The wireless network 101 may comprise one or more of a Wireless Wide Area Network
(WWAN) and a Wireless Local Area Network (WLAN) or other suitable network arrangements.
In some embodiments, the mobile communication device 201 is configured to communicate
over both the WWAN and WLAN, and to roam between these networks. In some embodiments,
the wireless network 101 may comprise multiple WWANs and WLANs. In some embodiments,
the mobile device 201 includes the communication subsystem 211 for WWAN communications
and a separate communication subsystem for WLAN communications. In most embodiments,
communications with the WLAN employ a different antenna than communications with the
WWAN. Accordingly, the antenna 10 may be configured for WWAN communications or WLAN
communications depending on the embodiment and desired application.
[0061] In some embodiments, the WWAN conforms to one or more of the following wireless network
types: Mobitex Radio Network, DataTAC, GSM (Global System for Mobile Communication),
GPRS (General Packet Radio System), TDMA (Time Division Multiple Access), CDMA (Code
Division Multiple Access), CDPD (Cellular Digital Packet Data), iDEN (integrated Digital
Enhanced Network), EvDO (Evolution-Data Optimized) CDMA2000, EDGE (Enhanced Data rates
for GSM Evolution), UMTS (Universal Mobile Telecommunication Systems), HSPDA (HighSpeed
Downlink Packet Access), IEEE 802.16e (also referred to as Worldwide Interoperability
for Microwave Access or "WiMAX), or various other networks. Although WWAN is described
as a "Wide-Area" network, that term is intended herein also to incorporate wireless
Metropolitan Area Networks (WMAN) and other similar technologies for providing coordinated
service wirelessly over an area larger than that covered by typical WLANs.
[0062] The WLAN comprises a wireless network which, in some embodiments, conforms to IEEE
802.11x standards (sometimes referred to as Wi-Fi) such as, for example, the IEEE
802.11a, 802.11b and/or 802.11g standard. Other communication protocols may be used
for the WLAN in other embodiments such as, for example, IEEE 802.11n, IEEE 802.16e
(also referred to as Worldwide Interoperability for Microwave Access or "WiMAX"),
or IEEE 802.20 (also referred to as Mobile Wireless Broadband Access). The WLAN includes
one or more wireless RF Access Points (AP) that collectively provide a WLAN coverage
area.
[0063] Certain adaptations and modifications of the described embodiments can be made. Therefore,
the above discussed embodiments are considered to be illustrative and not restrictive.
1. A mobile communication device, comprising:
a substrate having a ground plane and an antenna signal trace;
a microphone mounted to the substrate;
a metallic shield disposed over the microphone and being connected to the ground plane;
and
a radio frequency antenna formed in part from the metallic shield and having at least
one radiator arm connected to the metallic shield,
wherein the antenna includes a feed point connected to the antenna signal trace.
2. The mobile communication device claimed in claim 1, further including a non-metallic
acoustic tube disposed at least partly under the radiator arm.
3. The mobile communication device claimed in claim 2, further including a device casing,
the device casing having an acoustic opening, and wherein the non-metallic acoustic
tube defines an acoustic pathway between the acoustic opening and the microphone.
4. The mobile communication device claimed in any one of claims 1 to 3, wherein the metallic
shield includes a top section, and wherein the at least one radiator arm is connected
to the top section.
5. The mobile communication device claimed in claim 4, wherein the at least one radiator
arm includes a planar metal element having one end connected to the top section.
6. The mobile communication device claimed in claim 5, wherein the planar metal element
and the top section lie in the same plane.
7. The mobile communication device claimed in claim 4, wherein the antenna includes a
feed element having one end connected to the top section and another end connected
to the antenna signal trace.
8. The mobile communication device claimed in any one of claims 1 to 7, wherein the antenna
includes a feed element having one end connected to the metallic shield and another
end connected to the antenna signal trace.
9. The mobile communication device claimed in claim 1, wherein the metallic shield includes
a planar top section disposed substantially parallel to the substrate and spaced above
the microphone, and wherein the metallic shield includes at least two side walls extending
downwards from the edges of the planar top section, and wherein at least one of the
side walls is connected to the ground plane.
10. The mobile communication device claimed in claim 9, wherein the side walls define
an acoustic port through which the microphone is exposed to the environment external
to the device.
11. The mobile communication device claimed in claim 10, further including a non-metallic
acoustic shield within the metallic shield and over the microphone, and wherein the
non-metallic acoustic shield includes an acoustic tube extending from the acoustic
port and disposed at least partly under the radiator arm.
12. The mobile communications device claimed in any one of claims 10 to 11, further comprising
a device casing having an acoustic microphone opening in communication with the acoustic
port.
13. The mobile communications device claimed in claim 12, wherein the acoustic port is
located below the radiator arm, and further including a non-metallic acoustic tube
disposed beneath the radiator arm and defining an acoustic pathway between the acoustic
microphone opening and the acoustic port.
14. The mobile communications device claimed in any one of claims 1 to 13, wherein the
microphone comprises an electret condenser microphone.
15. The mobile communications device claimed in any one of claims 1 to 14, wherein the
electrostatic discharge shield is cylindrical.