(19)
(11)EP 2 659 467 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
24.02.2021 Bulletin 2021/08

(21)Application number: 11852911.4

(22)Date of filing:  18.10.2011
(51)International Patent Classification (IPC): 
G01S 19/34(2010.01)
(86)International application number:
PCT/US2011/056784
(87)International publication number:
WO 2012/091785 (05.07.2012 Gazette  2012/27)

(54)

POWER MANAGEMENT IN WIRELESS TRACKING DEVICE OPERATING WITH RESTRICTED POWER SOURCE

LEISTUNGSSTEUERUNG EINER DRAHTLOSEN VERFOLGUNGSVORRICHTUNG MIT EINGESCHRÄNKTER STROMQUELLE

GESTION D'ÉNERGIE DANS UN DISPOSITIF DE SUIVI SANS FIL FONCTIONNANT AVEC UNE SOURCE DE PUISSANCE LIMITÉE


(84)Designated Contracting States:
AL 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 RS SE SI SK SM TR

(30)Priority: 28.12.2010 US 980171

(43)Date of publication of application:
06.11.2013 Bulletin 2013/45

(60)Divisional application:
21150806.4

(73)Proprietor: FedEx Corporate Services, Inc.
Collierville, TN 38017 (US)

(72)Inventors:
  • TURON, Martin
    Milpitas, CA 95035 (US)
  • XIN, Yang
    Milpitas, CA 95035 (US)
  • DIERKS, Michael, P.
    Milpitas, CA 95035 (US)

(74)Representative: Finnegan Europe LLP 
1 London Bridge
London SE1 9BG
London SE1 9BG (GB)


(56)References cited: : 
WO-A1-2006/092466
US-A1- 2004 176 127
US-A1- 2008 086 391
US-A1- 2009 058 719
US-A1- 2010 033 424
US-B1- 6 339 397
US-A- 5 592 173
US-A1- 2004 192 352
US-A1- 2008 246 656
US-A1- 2009 312 032
US-A1- 2010 271 260
  
  • Maxim: "Maxim APP 886; Selecting the Right Comparator, The Function of a Comparator", , 13 December 2001 (2001-12-13), XP055350700, Retrieved from the Internet: URL:http://pdfserv.maximintegrated.com/en/ an/AN886.pdf [retrieved on 2017-03-01]
  
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

BACKGROUND OF THE INVENTION


1. Field of the Invention



[0001] This invention relates to managing operations of a wireless tracking device with a restricted power source, more specifically to operating the wireless tracking device in more than one mode of operation to reduce power consumption and prolong its operational time.

2. Background of the Invention



[0002] Wireless tracking devices are employed to track locations and conditions of various assets. Such wireless tracking devices are often mounted on the assets or placed in the vicinity of the assets. As the assets are transported or are exposed to changing environment, the wireless tracking devices detect the location and/or sense changing conditions of the assets. Then, the wireless tracking devices send wireless messages indicating the locations and/or other environment parameters of the assets to a remote monitoring station. Based on the collected information, the remote monitoring station may prompt actions such as sending reports to customers, taking remedial actions to prevent deterioration of the assets, and initiating retrieval of stolen assets.

[0003] Generally, a wireless tracking device includes various components and sensors enclosed in a casing. The casing provides robust protection against dirt or other contaminants as well as external forces. The wireless tracking device may include various components such as temperature sensors, humidity sensors, light sensors, accelerometers, gyroscopes, magnetometers, controllers, GPS modules and wireless communication modules. These components or modules may consume power during their operations. Some wireless tracking devices include sensors to accommodate diverse applications whereas other wireless tracking devices are equipped with fewer types of sensors selected for specific applications.

[0004] To provide power to these components and modules, a wireless tracking device includes a restricted power source such as batteries or solar cells. In many cases, the wireless tracking devices operate in environments where access to other power sources is unavailable. The wireless tracking devices often rely on the restricted power source for their operations. Hence, to increase the operable time of a wireless tracking device, it is necessary to reduce the power consumption of its components.

[0005] From US 2010/0271260 A1 a power-saving positioning device is known which includes a short-distance wireless communication unit for establishing a wireless connection with a short-distance wireless transceiver to perform a positioning tracking, a GPS receiving unit, for receiving a satellite signal for performing a positioning tracking, and a mobile communication unit for transmitting the positioning information to a remote control centre. If a signal intensity of a wireless connection between the power-saving positioning device and the short-distance device is greater than a threshold, the GPS receiving unit and the mobile communication unit will enter into a power saving mode; on the other hand if the wireless connection signal intensity is smaller than the threshold, the short-distance wireless communication unit will enter into the power saving mode to achieve the power-saving effect.

[0006] From US6339397 (B1) a system for tracking objects on the earth's surface using global positioning system (GPS) satellites is known, which periodically transmits that position information via radio signal to a base receiver to deliver the object's position to the end user. US 2004/0192352 A1 discloses a location tracking device which in response to a movement sensor sensing a cessation of movement transmits a message via a RF transmitter to a GSM network and thereafter places the GSM transceiver into a reduced battery power consumption mode of operation. US 2009/0058719 A1 discloses a wireless communication device with power saving functionality witch switches between a first mode and a second mode according to a connection status of a wireless connection.

SUMMARY OF THE INVENTION



[0007] The invention is defined by the appended claims.

[0008] The features and advantages described in the specification are not all inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes.

BRIEF DESCRIPTION OF THE DRAWINGS



[0009] 

Figure 1 is a conceptual diagram illustrating a wireless tracking device in a vehicle, according to one embodiment.

Figure 2 is a block diagram illustrating a wireless tracking device, according to one embodiment.

Figure 3 is a diagram illustrating a method of operating the wireless tracking device in more than one mode, according to one embodiment.

Figure 4 is a diagram illustrating a geofence associated with different modes of operation, according to one embodiment.

Figure 5 is a flowchart illustrating the process of switching between the active mode and the hibernation mode when the geofence is implemented.


DETAILED DESCRIPTION OF THE INVENTION



[0010] Embodiments described herein provide a wireless tracking device operating in at least two modes to reduce power consumption and extend the operable time of the wireless tracking device. In an active mode, the wireless tracking device activates a communication module for communicating with a remote device via wireless connection or other components that consume a large amount of power. In a hibernation mode, the components or modules in the wireless tracking device are shut down to reduce power consumption. The wireless tracking device may switch from the hibernation mode to the active mode selectively when a predetermine event is detected.

Example Use of Wireless Tracking Device



[0011] Figure 1 is a diagram illustrating a wireless tracking device 122 in a moving vehicle 120. The wireless tracking device 122 may be located in a cargo 126 being transported by the vehicle 120. In this example, the wireless tracking device 122 tracks its location using a Global Positioning System (GPS) module that detects signals from satellites 110. The wireless tracking device 122 inside cargoes 126 also communicates with a remote monitoring station 128 over a wireless communication channel 130.

[0012] The vehicle 120 may carry multiple units of cargoes 126 where each unit is equipped with a wireless tracking device 122. Each cargo 126 may be destined to a different target location. As a cargo 126 is transported, a wireless tracking device 122 attached to the cargo 126 tracks the location of the cargo 126 and environmental conditions surrounding the cargo 126. Then, the location and other environment information are transmitted to a remote monitoring station 128 in a wireless message.

[0013] The environment conditions detected by the wireless tracking device 122 may include, but are not limited to, temperature, humidity, light, sound, vibration, tilt, shock, certain types of chemical compounds, pressure, magnetic field, smoke, and movements. The wireless tracking device 122 may be configured to detect some or all of these environment conditions.

[0014] The use of wireless tracking device 122 is not limited to moving cargoes 126. The wireless tracking device 122 may be used for an object that remains stationary. In such case, the wireless tracking device 122 is used primarily for detecting environmental conditions surrounding the wireless tracking device 122. Further, the vehicle 120 is merely an example of a mode of transport. The wireless tracking device 122 and the cargo 126 may be transported using other modes of transport such as vessels, trains or airplanes. Cargo 126 may be any asset transported in commerce, including among other things, envelopes, parcels, express packages, boxes, palettes, containers, crates, and specialty goods and materials.

Example Structure of Wireless Tracking Device



[0015] The wireless tracking device 122 operates in two distinct modes: an active mode and a hibernation mode. In the active mode, most or all of the components in the wireless tracking device 122 are activated. The activated components include high power consumption components such as a wireless communication module. In the hibernation mode, a fewer number of components or modules in the wireless tracking device 122 are activated. Other components or modules are turned off to preserve power. The wireless tracking device 122 switches between the active mode and the hibernation mode in response to detecting or in anticipation of an event.

[0016] Figure 2 is a block diagram illustrating the wireless tracking device 122, according to one embodiment. The wireless tracking device 122 may include, among other components, a high power system controller 210, a low power system controller 214, a Global Positioning System (GPS) module 222, a wireless communication module 226, a power manager 230, a restricted power source 234, and various sensors 250 through 262. The wireless tracking device 122 may include other components not illustrated in Figure 2 such as an input module or speakers.

[0017] The wireless tracking device 122 of Figure 2 has a dual processor structure including two controllers: the high power system controller 210 and the low power system controller 214. By using the two controllers, the power consumption may be reduced in the hibernation mode while obtaining high computing capacity during the active mode. When the wireless tracking device 122 is placed in the active mode, the high power system controller 210 becomes active and performs power intensive operations. Such power intensive operations include, for example, determining the location of the wireless tracking device 122 using the GPS module 222 and communicating wirelessly with the remote monitoring station 128 via the wireless communication module 226. During the hibernation mode, the wireless tracking device 122, the GPS module 222 and the wireless communication module 226 may be disabled to reduce power consumption.

[0018] In one embodiment, the low power system controller 214 is embodied as ATMEGA 8-bit microcontroller (available from Atmel Corporation of San Jose, California), Energy Micro Gecko micro controller (available from Energy Micro AS of Oslo, Norway) or SAM3 (available from Atmel Corporation of San Jose, California). Examples of the high power system controllers 210 include the Marvell PXA series, ARM11, Cortex-A series, or TI DSPs.

[0019] In one embodiment, the high power system controller 210 controls the operation of the GPS module 222 and the wireless communication module 226. When the high power system controller 210 is turned off, the GPS module 222 and the wireless communication module 226 are also deactivated to reduce power consumption.

[0020] The low power system controller 214 remains active in both the active mode and the hibernation mode. The low power system controller 214 determines whether to place the wireless tracking device 122 in the active mode or the hibernation mode, as described below in detail with reference to Figure 3. In one embodiment, the low power system controller 214 is connected to low-power consumption components such as sensors 250 through 262. The low power system controller 214 continues to receive sensor signals 282 through 294 even in the hibernation mode to avoid losing meaningful sensor data. However, the sampling rate and the sensitivity of the sensor signals 282 through 294 may be reduced in the hibernation mode to reduce power consumption.

[0021] The low power system controller 214 sends commands to the power manager 230 to turn on or off power provided to the high power system controller 210. When the low power system controller 214 issues a command indicating that the wireless tracking device 122 should be placed in the hibernation mode, the power manager 230 turns off power to the high power system controller 210.

[0022] The power manager 230 is connected to the power source 234. The power source 234 may be a restricted power source such as a battery or solar cells. In one embodiment, the power source 234 includes a charge circuit. The charger circuit receives charging electric current via port 238 to charge the battery.

[0023] The GPS module 222 may include an antenna and a signal processing unit for receiving GPS signals. The GPS module 222 operates under the command of the high power system controller 210 to identify the current location of the wireless tracking device 122. In one embodiment, the GPS module 222 embodies A-GPS (Assisted GPS) which improves the startup performance or TTFF (Time To First Fix) by utilizing data received via the wireless communication module 226. For this purpose, the GPS module 222 receives ephemeris data from a remote server via the wireless communication module 226.

[0024] The wireless communication module 226 includes a transceiver for sending or receiving data to or from the remote monitoring station 128. The wireless communication module 226 may establish communicating using various communication protocols such as GSM, WiFi, Bluetooth, Zigbee, UMTS/HSxPA, 3GPP Long Term Evolution (LTE) and WiMAX.

[0025] The sensors 250 through 262 detect various physical properties or conditions and send the sensor signals 282 through 294 to the low power system controller 214. The sensors in the wireless tracking device 122 include, for example, an accelerometer 250, a light sensor 254, a temperature sensor 258 and a humidity sensor 262. The wireless tracking device 122 may include other types of sensors to detect different physical properties or conditions.

[0026] The high power system controller 210 and the low power system controller 214 communicate over a data bridge 212. The high power system controller 210 may receive the sensor data from the low power system controller 214, compiles the sensor data into a message, and sends the message to the remote monitoring station 128 via the wireless communication module 226. On the other hand, the low power system controller 214 receives location information (based on the GPS module 222) from the high power system controller 210 or any data (e.g., control commands) received from the remote monitoring station 128 via the data bridge 212.

[0027] The high power system controller 210 and the low power system controller 214 include computer readable storage medium 270 and computer readable storage medium 272, respectively. The computer readable storage medium 270 stores instructions for execution by the high power system controller 210. The computer readable storage medium 272 stores instructions for execution by the low power system controller 214. In one embodiment, the computer readable storage media 270, 272 are embodied as a non-volatile memory device (e.g., EEPROM (Electrically Erasable Programmable Read-Only Memory) or a flash memory), a volatile memory device (e.g., Random Access Memory (RAM)) or a combination of both.

[0028] The embodiment of Figure 2 is merely illustrative. Wireless tracking devices of different configuration may also be used. For example, a single processor architecture including only a single controller may be used. In the single processor architecture, all the components and sensors are connected and controlled by the single controller. In one embodiment, the single controller may operate in two modes: an active mode with a higher processing capacity, and a hibernation mode with reduced power consumption. In yet another embodiment, the high power system controller 210 and the low power system controller 214 could also be implemented in a multi core configuration or via virtualization with a single core.

Power Mode Switching Scheme



[0029] Figure 3 is a diagram illustrating a method of placing the wireless tracking device 122 in the active mode or the hibernation mode, according to one embodiment. The low power system controller 214 receives 310 the sensor signals 282 through 294 from the sensors 250 through 262 or the location of the wireless tracking device 122 from the GPS module 222. For this purpose, the low power system controller 214 stores instructions for switching power modes in the computer readable storage medium 272.

[0030] Then, the low power system controller 214 determines 312 if one or more of predetermined events are detected to place the wireless tracking device 122 in the active mode. Various types of events may be used for switching the modes. The wireless tracking device 122 is placed in the active mode when events of interest to a user are likely to occur or continue whereas the wireless tracking device 122 is placed in the hibernation mode when the events of interest are unlikely to occur or continue.

[0031] If one or more of predetermined events are detected, the low power system controller 214 places or maintains 314 the wireless tracking device 122 in the active mode. In one embodiment, the predetermined events include detection of movement of the wireless tracking device 122 by the accelerometer sensor or the speed of the wireless tracking device 122 above a threshold. While the wireless tracking device 122 is in the active mode, the low power system controller 214 may monitor changes in the location based on GPS signals from the current active mode session to determine the speed of the wireless tracking device 122. Alternatively, the low power system controller 214 may compare the location of the wireless tracking device 122 with the location of the wireless tracking device 122 in the previous active mode session to determine the speed of the wireless tracking device 122.

[0032] In one embodiment, the wireless tracking device 122 is placed or maintained 314 in the active mode when external events are detected via the sensors 250 through 262. The external events refer to events occurring outside the wireless tracking device 122 and may include, for example, (i) a motion of the wireless tracking device 122 (as detected by the accelerometer 250), (ii) changes from indoor to outdoor or vice versa (as detected by the light sensor 254), (iii) changes in temperature (as detected by the temperature sensor 258), (iv) changes in the humidity (as detected by the humidity sensor 262), and (v) detection of certain chemical compounds or smoke. If such external events are detected, events of interest are likely to ensue or continue. Hence, the wireless tracking device 122 is maintained in the active mode to capture data associated with the external events.

[0033] In one embodiment, the event may be passing of time or a signal from a timer indicating a predetermined time. The low power system controller 214 may periodically switch the wireless tracking device 122 to the active mode. The low power system controller 214 switches to the active mode more often or stays in the active mode for a longer time when the accelerometer 250 sends a signal 282 indicating the movement of the wireless tracking device 122. The wireless tracking device 122 is more likely to experience significant changes in the environment when the wireless tracking device 122 is being transported. Hence, the wireless tracking device 122 is placed in the active mode to send more frequent updates to the remote monitoring station 128. The low power system controller 214 may switch back to the hibernation mode if a certain amount of time is elapsed.

[0034] If no significant events are detected for a predetermined amount of time, the low power system controller 214 places or maintains 318 the wireless tracking device 122 in the hibernation mode. The wireless tracking device 122 is unlikely to encounter significant changes when predetermined events are not detected. Hence, the low power system controller 214 places the wireless tracking device 122 in the hibernation mode to preserve power.

[0035] After placing or maintaining 314, 318 the wireless tracking device 122 in the active mode or the hibernation mode, the process returns to receiving 310 the sensor signals or locations.

[0036] In one embodiment, more significant events in the sensor signals or more drastic changes in locations are needed to switch the wireless tracking device 122 from the hibernation mode to the active mode compared to the events for maintaining the wireless tracking device 122 in the active mode. The sensitivity of sensors (e.g., the accelerometer 250) is lowered in the hibernation mode to avoid the wireless tracking device 122 from waking up to the active mode due to minor variances in the sensor signals.

[0037] In contrast, if the wireless tracking device 122 is currently in the active mode, the sensitivity of the sensors is increased. The fact that the wireless tracking device 122 is currently in the active mode indicates that the wireless tracking device 122 is likely to experience other significant events. By adjusting the sensitivity to sensor signals and location changes based on the mode of the wireless tracking device 122, the wireless tracking device 122 may be prevented from waking up due to insignificant events while retaining the chance of detecting significant events.

Geofencing of Wireless Tracking Device



[0038] The wireless tracking device 122 may move through a geographic region where wireless communication is not available or where reception of the wireless communication is poor. In one embodiment, such geographic region may be established as a goefence in which the wireless tracking device 122 does not attempt to communicate with the remote monitoring station 128. A geofence herein refers to a geographical area artificially defined for one purpose or the other. By avoiding communication in the geofenced area, power consumption associated with attempting to communicate with the remote monitoring station 128 in a poor reception area can be avoided. In addition, this feature may be used to satisfy certain regulatory requirements about RF transmissions in particular areas.

[0039] Figure 4 is a diagram illustrating a geofence 410 associated with wireless communication of the wireless tracking device 122 where wireless communication is unavailable or the signal reception is poor. Within the geofence 410, the wireless tracking device 122 does not attempt to communicate with the remote monitoring station 128. Data collected for events while the wireless tracking device 122 remains in the geofence 410 are stored and then transmitted to the remote monitoring station 128 when the wireless tracking device 122 leaves the geofence 410. In Figure 4, region 420 represents an area where the wireless communication of the wireless tracking device 122 is available with good reception.

[0040] In the example of Figure 4, the wireless tracking device 122 moves from point X to point Z. While the wireless tracking device 122 is in the region 420 and distanced away from the geofence 410 (represented by line X-Y), the wireless tracking device 122 switches to the active mode at a first frequency (i.e. sampling interval). As the wireless tracking device 122 approaches the geofence 410 (represented by line Y-Z), the wireless tracking device 122 switches to the active mode at a second frequency higher than the first frequency (i.e., the wireless tracking device 122 is placed in the active mode more often). For example, the wireless tracking device 122 may switch from the hibernation mode to the active mode every 10 minutes when the wireless tracking device 122 is traveling from point X to point Y. The same wireless tracking device 122 may switch from the hibernation mode to the active mode every 5 minutes when the wireless tracking device 122 is traveling from point Y to point Z.

[0041] In one embodiment, the wireless tracking device 122 gradually switches to active mode with increasing frequency or stays in the active mode for a longer time as the wireless tracking device 122 approaches the geofence 410.

[0042] Figure 5 is a flowchart illustrating the process of switching between the active mode and the hibernation mode when the geofence 410 is implemented. First, the wireless tracking device 122 switches 508 to the active mode. In the active mode, the low power system controller 214 determines 510 the location, the moving direction and the speed of the wireless tracking device 122. Based on the location, the moving direction and the speed of the wireless tracking device 122, the wireless tracking device 122 computes 514 the estimated time that the wireless tracking device 122 will arrive at the region of the geofence 410.

[0043] Based on the estimated time of arrival at the region of the geofence 410, the interval for switching to the active mode is determined 518. After any process in the current active mode is finished or preset time for staying in the active mode is elapsed, the wireless tracking device 122 switches 522 to the hibernation mode.

[0044] Then the wireless tracking device 122 determines 526 whether it is time to switch to the active mode based on the computed interval. If it is time to switch to the active mode, the process proceeds to switch 508 the wireless tracking device 122 to the active mode and repeats the subsequent steps. If it is not yet time to switch to the active mode, the wireless tracking device 122 remains 522 in the hibernation mode.

[0045] By adjusting the interval for placing the wireless tracking device 122 in the hibernation mode based on the estimated time of arrival at a poor wireless signal reception area, the wireless tracking device 122 can continue to update the remote monitoring station with wireless messages without using excessive amount of power.


Claims

1. A wireless tracking device (122), comprising:

a locating device (222) configured to determine a geographic location of the wireless tracking device (122);

at least one sensor (250) configured to generate a sensor signal (282), the sensor signal (282) representing a condition or a property associated with the wireless tracking device (122);

at least one controller (210) coupled to the location device (222) and the at least one sensor (250), the at least one controller (210) configured to:

generate a message indicating the geographic location and the condition or the property associated with the wireless tracking device (122),

place the wireless tracking device (122) in a hibernation mode for a predetermined amount of time,

switch the wireless tracking device (122) to an active mode in response to receiving, from the at least one sensor (250), a sensor signal (282) indicating a change exceeding a first sensitivity corresponding to a first external event, wherein the active mode consumes more power than the hibernation mode,

increase the sensitivity for detecting an event by the at least one sensor (250) to a second sensitivity while the wireless tracking device (122) is in the active mode, and

maintain the wireless tracking device (122) in the active mode in response to receiving a sensor signal (282) indicating a change exceeding the i second sensitivity corresponding to a second external event; and

a communication module (226) configured to send the message via a wireless network;

wherein the locating device (222) and the communication module (226) are configured to operate in the active mode but not in the hibernation mode and to be intermittently operated in the active mode.


 
2. The wireless tracking device (122) of claim 1, wherein the at least one controller (210, 214) comprises a first controller (214) and a second controller (210) consuming more power than the first controller (214) during operation.
 
3. The wireless tracking device (122) of claim 2, wherein the first controller (214) is configured to receive sensor signals (282, 286, 290, 294) from a plurality of sensors (250, 254, 258, 262), and wherein the second controller (210) is configured to operate the locating device (222) and the communication module (226).
 
4. The wireless tracking device (122) of claim 3, wherein the first controller (214) is configured to turn off the second controller (210), the locating device (222) and the communication module (226) in the hibernation mode.
 
5. The wireless tracking device (122) of claim 1, further comprising a restricted power source (234) for providing power to the locating device (222), the at least one controller (210) and the communication module (226).
 
6. The wireless tracking device (122) of claim 1, wherein the locating device (222) comprises a Global Positioning System, GPS, module.
 
7. The wireless tracking device (122) of claim 6, wherein the locating device (222) configured to receive ephemeris data from a remote server via the communication module (226).
 
8. The wireless tracking device (122) of claim 1, wherein the at least one controller (210) is further configured to:

compute an estimated time of arrival of the wireless tracking device at a geographical region where the message is not to be sent via the wireless network;

determine an interval for switching the wireless tracking device from the hibernation mode to the active mode, wherein the interval is determined based on proximity to a geofence; and

determine whether to switch to the active mode based on the determined interval.


 
9. The wireless tracking device (122) of claim 8, wherein the interval is shortened as the wireless tracking device approaches the geofence.
 
10. The wireless tracking device of claim 1, wherein the at least one controller (210) is further configured to: compute a distance between the wireless tracking device (122) and a boundary of a geographical region where the message is not to be sent via the wireless network; determine an interval for switching the wireless tracking device from the hibernation mode to the active mode, the interval being selected depending on the distance; and determine whether to switch to the active mode based on the determined interval.
 
11. The wireless tracking device (122) of claim 1, wherein the at least one sensor (250) comprises an accelerometer.
 
12. A method of operating a wireless tracking device (122) comprisng a locating device (222), at least one sensor (250) and a communication module (226), the method comprising:

placing the wireless tracking device (122) in a hibernation mode;

generating a sensor signal (282) by the at least on sensor (250), the sensor signal (282) representing a condition or property associated with the wireless tracking device (122);

switching the wireless tracking device (122) to an active mode in response to a sensor signal (282) indicating a change exceeding a first sensitivity corresponding to a first external event, wherein the active mode consumes more power than the hibernation mode;

increasing the sensitivity of the at least on sensor (250) for detecting an event to a second sensitivity while the wireless tracking device (122) is in the active mode;

determining a geographic location of the wireless tracking device 122) by the locating device (222);

generating a message indicating the geographic location, the condition or the property associated with the wireless tracking device (122);

sending the message via a wireless network by the communication module (226); and

maintaining the wireless tracking device (122) in the active mode responsive to receiving a sensor signal (282) indicating a change exceeding the second sensitivity corresponding to a second external event;

wherein the locating device (222) and the communication module (226) are operable in the active mode but not in the hibernation mode and a are intermittently operated in the active mode.


 
13. The method of claim 12, wherein in the hibernation mode, one of two controllers is turned off.
 
14. The method of claim 12, wherein the location is determined by using a Global Positioning, System, GPS.
 
15. The method of claim 14, further comprising receiving ephemeris data from a remote server via the wireless network.
 
16. The method of claim 12, further comprising:

computing an estimated time of arrival of the wireless tracking device at a geographical region where the message is not to be sent via the wireless network;

determining an interval for switching the wireless tracking device from the hibernation mode to the active mode; and

determining whether to switch to the active mode based on the determined interval, wherein the interval is determined based on proximity to a geofence (410).


 
17. The method of claim 16, wherein the interval is shortened as the wireless tracking device approaches the geofence (410).
 
18. The method of claim 12, wherein the sensor signal (282) is generated by an accelerometer (250).
 
19. A non-transitory computer-readable storage medium structured to store instructions executable by a processor in a wireless tracking device (122) comprising a locating device (222), at least one sensor (250) and a communication module (226), the instructions, when executed, causing the processor to:

place the wireless tracking device (122) in a hibernation mode for a predetermined amount of time;

generate a sensor signal (282) by the at least one sensor (250), the sensor signal (282) representing a condition or property associated with the wireless tracking device;

switch the wireless tracking device (122) to an active mode in response to a sensor signal (282) indicating a change exceeding a first sensitivity corresponding to a first external event, the active mode consuming more power than the hibernation mode;

increasing the sensitivity of the at least one sensor (250) for detecting an event to a second sensitivity while the wireless tracking device (122) is in the active mode;

determine a geographic location of the wireless tracking device (122) by the locating device (222);

generate a message indicating the geographic location, the condition or the property associated with the wireless tracking device;

send the message via a wireless network by the communication module (226); and

maintain the wireless tracking device (122) in the active mode responsive to receiving a sensor signal (282) indicating a change exceeding the second sensitivity corresponding to a second external event;

wherein the locating device (222) and the communication module (226) are operable in the active mode but not in the hibernation mode and a are intermittently operated in the active mode.


 


Ansprüche

1. Drahtlose Verfolgungsvorrichtung (122), umfassend:

eine Ortungsvorrichtung (222), die konfiguriert ist, um einen geografischen Standort der drahtlosen Verfolgungsvorrichtung (122) zu bestimmen;

mindestens einen Sensor (250), der konfiguriert ist, um ein Sensorsignal (282) zu erzeugen, wobei das Sensorsignal (282) einen Zustand oder eine Eigenschaft darstellt, die der drahtlosen Verfolgungsvorrichtung (122) zugeordnet ist;

mindestens eine Steuerung (210), die mit der Ortungsvorrichtung (222) und dem mindestens einen Sensor (250) verbunden ist, wobei die mindestens eine Steuerung (210) konfiguriert ist, um:

eine Nachricht zu erzeugen, die den geografischen Standort und den Zustand oder die Eigenschaft angibt, die der drahtlosen Verfolgungsvorrichtung (122) zugeordnet sind,

die drahtlose Verfolgungsvorrichtung (122) für eine vorbestimmte Zeitdauer in einen Ruhezustand zu versetzen,

die drahtlose Verfolgungsvorrichtung (122) in einen aktiven Modus als Reaktion auf das Empfangen, von dem mindestens einen Sensor (250), eines Sensorsignals (282) umzuschalten, das eine Änderung anzeigt, die eine erste Empfindlichkeit überschreitet, die einem ersten externen Ereignis entspricht, wobei der aktive Modus mehr Strom verbraucht als der Ruhezustand,

die Empfindlichkeit zum Erfassen eines Ereignisses durch den mindestens einen Sensor (250) auf eine zweite Empfindlichkeit zu erhöhen, während sich die drahtlose Verfolgungsvorrichtung (122) im aktiven Modus befindet, und

die drahtlose Verfolgungsvorrichtung (122) im aktiven Modus als Reaktion auf das Empfangen eines Sensorsignals (282) zu halten, das eine Änderung anzeigt, die die zweite Empfindlichkeit überschreitet, die einem zweiten externen Ereignis entspricht; und

ein Kommunikationsmodul (226),

das konfiguriert ist, um die Nachricht über ein drahtloses Netzwerk zu senden;

wobei die Ortungsvorrichtung (222) und das Kommunikationsmodul (226) konfiguriert sind, um im aktiven Modus, jedoch nicht im Ruhezustand zu arbeiten und intermittierend im aktiven Modus betrieben zu werden.


 
2. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 1, wobei die mindestens eine Steuerung (210, 214) eine erste Steuerung (214) und eine zweite Steuerung (210), die während des Betriebs mehr Energie verbraucht als die erste Steuerung (214), umfasst.
 
3. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 2, wobei die erste Steuerung (214) konfiguriert ist, um Sensorsignale (282, 286, 290, 294) von mehreren Sensoren (250, 254, 258, 262) zu empfangen, und wobei die zweite Steuerung (210) konfiguriert ist, um das Ortungsgerät (222) und das Kommunikationsmodul (226) zu betreiben.
 
4. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 3, wobei die erste Steuerung (214) konfiguriert ist, um die zweite Steuerung (210), die Ortungsvorrichtung (222) und das Kommunikationsmodul (226) im Ruhezustand auszuschalten.
 
5. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 1, ferner umfassend eine eingeschränkte Energiequelle (234) zum Zuführen von Energie an die Ortungsvorrichtung (222), die mindestens eine Steuerung (210) und das Kommunikationsmodul (226).
 
6. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 1, wobei die Ortungsvorrichtung (222) ein Global Positioning System, GPS, -Modul umfasst.
 
7. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 6, wobei die Ortungsvorrichtung (222) konfiguriert ist, um Ephemeridendaten von einem entfernten Server über das Kommunikationsmodul (226) zu empfangen.
 
8. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 1, wobei die mindestens eine Steuerung (210) ferner konfiguriert ist, um:

eine geschätzte Ankunftszeit der drahtlosen Verfolgungsvorrichtung in einer geografischen Region zu berechnen, in der die Nachricht nicht über das drahtlose Netzwerk gesendet werden soll;

ein Intervall zum Umschalten der drahtlosen Verfolgungsvorrichtung vom Ruhezustand in den aktiven Modus zu bestimmen, wobei das Intervall basierend auf der Nähe zu einem Geofence bestimmt wird; und

zu bestimmen, ob in den aktiven Modus basierend auf dem bestimmten Intervall umgeschaltet werden soll.


 
9. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 8, wobei das Intervall verkürzt wird, wenn sich die drahtlose Verfolgungsvorrichtung dem Geofence nähert.
 
10. Drahtlose Verfolgungsvorrichtung nach Anspruch 1, wobei die mindestens eine Steuerung (210) ferner konfiguriert ist, um: eine Entfernung zwischen der drahtlosen Verfolgungsvorrichtung (122) und einer Grenze einer geografischen Region zu berechnen, in der die Nachricht nicht über das drahtlose Netzwerk gesendet werden soll; ein Intervall zum Umschalten der drahtlosen Verfolgungsvorrichtung vom Ruhezustand in den aktiven Modus zu bestimmen, wobei das Intervall in Abhängigkeit von der Entfernung ausgewählt wird; und zu bestimmen, ob in den aktiven Modus basierend auf dem bestimmten Intervall umgeschaltet werden soll.
 
11. Drahtlose Verfolgungsvorrichtung (122) nach Anspruch 1, wobei der mindestens eine Sensor (250) einen Beschleunigungsmesser umfasst.
 
12. Verfahren zum Betreiben einer drahtlosen Verfolgungsvorrichtung (122), umfassend
eine Ortungsvorrichtung (222), mindestens einen Sensor (250) und ein Kommunikationsmodul (226), wobei das Verfahren umfasst:

Versetzen der drahtlosen Verfolgungsvorrichtung (122) in einen Ruhezustand;

Erzeugen eines Sensorsignals (282) durch den mindestens eingeschalteten Sensor (250),

wobei das Sensorsignal (282) einen Zustand oder eine Eigenschaft darstellt, die der drahtlosen Verfolgungsvorrichtung (122) zugeordnet sind;

Umschalten der drahtlosen Verfolgungsvorrichtung (122) in einen aktiven Modus als Reaktion auf ein Sensorsignal (282), das eine Änderung anzeigt, die eine erste Empfindlichkeit überschreitet, die einem ersten externen Ereignis entspricht, wobei der aktive Modus mehr Strom verbraucht als der Ruhezustand;

Erhöhen der Empfindlichkeit des mindestens eingeschalteten Sensors (250) zum Erfassen eines Ereignisses auf eine zweite Empfindlichkeit, während sich die drahtlose Verfolgungsvorrichtung (122) im aktiven Modus befindet;

Bestimmen eines geografischen Standortes der drahtlosen Verfolgungsvorrichtung (122) durch die Ortungsvorrichtung (222);

Erzeugen einer Nachricht, die den geografischen Standort, den Zustand oder die Eigenschaft angibt, die der drahtlosen Verfolgungsvorrichtung (122) zugeordnet sind;

Senden der Nachricht über ein drahtloses Netzwerk durch das Kommunikationsmodul (226); und

Halten der drahtlosen Verfolgungsvorrichtung (122) im aktiven Modus als Reaktion auf das Empfangen eines Sensorsignals (282), das eine Änderung anzeigt, die die zweite Empfindlichkeit überschreitet, die einem zweiten externen Ereignis entspricht;

wobei die Ortungsvorrichtung (222) und das Kommunikationsmodul (226) im aktiven Modus, jedoch nicht im Ruhezustand betriebsbereit sind und intermittierend im aktiven Modus betrieben werden.


 
13. Verfahren nach Anspruch 12, wobei im Ruhezustand eine von zwei Steuerungen ausgeschaltet ist.
 
14. Verfahren nach Anspruch 12, wobei der Standort durch Verwenden eines Global Positioning Systems, GPS, bestimmt wird.
 
15. Verfahren nach Anspruch 14, ferner umfassend das Empfangen von Ephemeridendaten von einem entfernten Server über das drahtlose Netzwerk.
 
16. Verfahren nach Anspruch 12, ferner umfassend:

Berechnen einer geschätzten Ankunftszeit der drahtlosen Verfolgungsvorrichtung in einer geografischen Region, in der die Nachricht nicht über das drahtlose Netzwerk gesendet werden soll;

Bestimmen eines Intervalls zum Umschalten der drahtlosen Verfolgungsvorrichtung vom Ruhezustand in den aktiven Modus; und

Bestimmen, ob in den aktiven Modus basierend auf dem bestimmten Intervall umgeschaltet werden soll, wobei das Intervall basierend auf der Nähe zu einem Geofence (410) bestimmt wird.


 
17. Verfahren nach Anspruch 16, wobei das Intervall verkürzt wird, wenn sich die drahtlose Verfolgungsvorrichtung dem Geofence (410) nähert.
 
18. Verfahren nach Anspruch 12, wobei das Sensorsignal (282) durch einen Beschleunigungsmesser (250) erzeugt wird.
 
19. Nicht flüchtiges computerlesbares Speichermedium, das strukturiert ist, um Anweisungen zu speichern, die von einem Prozessor in einer drahtlosen Verfolgungsvorrichtung (122) ausführbar sind, die eine Ortungsvorrichtung (222), mindestens einen Sensor (250) und ein Kommunikationsmodul (226) umfasst,
wobei die Anweisungen bei deren Ausführung bewirken, dass der Prozessor:

die drahtlose Verfolgungsvorrichtung (122) für eine vorbestimmte Zeitdauer in einen Ruhezustand versetzt;

ein Sensorsignal (282) durch den mindestens einen Sensor (250) erzeugt,

wobei das Sensorsignal (282) einen Zustand oder eine Eigenschaft darstellt, die der drahtlosen Verfolgungsvorrichtung zugeordnet sind;

die drahtlose Verfolgungsvorrichtung (122) in einen aktiven Modus als Reaktion auf ein Sensorsignal (282) umschaltet, das eine Änderung anzeigt, die eine erste Empfindlichkeit überschreitet, die einem ersten externen Ereignis entspricht, wobei der aktive Modus mehr Strom verbraucht als der Ruhezustand;

Erhöhen der Empfindlichkeit des mindestens einen Sensors (250) zum Erfassen eines Ereignisses auf eine zweite Empfindlichkeit,

während sich die drahtlose Verfolgungsvorrichtung (122) im aktiven Modus befindet;

einen geografischen Standort der drahtlosen Verfolgungsvorrichtung (122) durch die Ortungsvorrichtung (222) bestimmt;

eine Nachricht erzeugt, die den geografischen Standort, den Zustand oder die Eigenschaft angibt, die der drahtlosen Verfolgungsvorrichtung zugeordnet sind;

die Nachricht über ein drahtloses Netzwerk durch das Kommunikationsmodul (226) sendet; und

die drahtlose Verfolgungsvorrichtung (122) im aktiven Modus als Reaktion auf das Empfangen eines Sensorsignals (282) hält, das eine Änderung anzeigt, die die zweite Empfindlichkeit überschreitet, die einem zweiten externen Ereignis entspricht;

wobei die Ortungsvorrichtung (222) und das Kommunikationsmodul (226) im aktiven Modus, jedoch nicht im Ruhezustand betriebsbereit sind und intermittierend im aktiven Modus betrieben werden.


 


Revendications

1. Dispositif de suivi sans fil (122), comprenant :

un dispositif de localisation (222) configuré pour déterminer un emplacement géographique du dispositif de localisation sans fil (122) ;

au moins un capteur (250) configuré pour générer un signal de capteur (282), le signal de capteur (282) représentant une condition ou une propriété associée au dispositif de suivi sans fil (122) ;

au moins un dispositif de commande (210) couplé au dispositif de localisation (222) et à l'au moins un capteur (250), le au moins un dispositif de commande (210) étant configuré pour :

générer un message indiquant l'emplacement géographique et la condition ou la propriété associée au dispositif de suivi sans fil (122),

le placement du dispositif de suivi sans fil (122) dans un mode hibernation pendant une quantité de temps prédéfinie,

la commutation du dispositif de suivi sans fil (122) vers un mode actif en réponse à la réception, en provenance du au moins un capteur (250), d'un signal de capteur (282) indiquant un changement dépassant une première sensibilité correspondant à un premier événement externe, ledit mode actif consommant plus d'énergie que le mode hibernation,

l'augmentation de la sensibilité en vue de la détection d'un événement par le au moins un capteur (250) à une seconde sensibilité pendant que le dispositif de suivi sans fil (122) est en mode actif, et

le maintien du dispositif de suivi sans fil (122) dans le mode actif en réponse à la réception d'un signal de capteur (282) indiquant un changement dépassant la seconde sensibilité correspondant à un second événement externe ; et

un module de communication (226)

configuré pour envoyer le message par l'intermédiaire d'un réseau sans fil ;

ledit dispositif de localisation (222) et le module de communication (226) étant configurés pour fonctionner en mode actif mais pas en mode hibernation et pour fonctionner par intermittence en mode actif.


 
2. Dispositif de suivi sans fil (122) selon la revendication 1, ledit au moins un dispositif de commande (210, 214) comprenant un premier dispositif de commande (214) et un second dispositif de commande (210) consommant plus d'énergie que le premier dispositif de commande (214) durant le fonctionnement.
 
3. Dispositif de suivi sans fil (122) selon la revendication 2, ledit premier dispositif de commande (214) étant configuré pour recevoir des signaux de capteur (282, 286, 290,294) en provenance d'une pluralité de capteurs (250,254,258,262), et ledit second dispositif de commande (210) étant configuré pour faire fonctionner le dispositif de localisation (222) et le module de communication (226).
 
4. Dispositif de suivi sans fil (122) selon la revendication 3, ledit premier dispositif de commande (214) étant configuré pour couper le second dispositif de commande (210), le dispositif de localisation (222) et le module de communication (226) dans le mode d'hibernation.
 
5. Dispositif de suivi sans fil (122) selon la revendication 1, comprenant en outre une source de puissance restreinte (234) destinée à fournir une puissance au dispositif de localisation (222), à l'au moins un dispositif de commande (210) et au module de communication (226).
 
6. Dispositif de localisation sans fil (122) selon la revendication 1, ledit dispositif de localisation (222) comprenant un module de système de positionnement par satellites, GPS.
 
7. Dispositif de localisation sans fil (122) selon la revendication 6, ledit dispositif de localisation (222) étant configuré pour recevoir des données d'éphémérides en provenance d'un serveur distant par l'intermédiaire du module de communication (226).
 
8. Dispositif de suivi sans fil (122) selon la revendication 1, ledit au moins un dispositif de commande (210) étant en outre configuré pour :

calculer une heure d'arrivée estimée du dispositif de suivi sans fil dans une région géographique où le message ne doit pas être envoyé par l'intermédiaire du réseau sans fil ;

déterminer un intervalle pour faire passer le dispositif de suivi sans fil du mode d'hibernation au mode actif, l'intervalle étant déterminé sur la base de la proximité d'une barrière géographique ; et

déterminer de passer ou none dans le mode actif en fonction de l'intervalle déterminé.


 
9. Dispositif de suivi sans fil (122) selon la revendication 8, ledit intervalle étant raccourci à mesure que le dispositif de suivi sans fil s'approche de la barrière géographique.
 
10. Dispositif de suivi sans fil selon la revendication 1, ledit au moins un dispositif de commande (210) étant en outre configuré pour : calculer une distance entre le dispositif de suivi sans fil (122) et une limite d'une région géographique où le message ne doit pas être envoyé par l'intermédiaire du réseau sans fil ; déterminer un intervalle pour faire passer le dispositif de suivi sans fil du mode d'hibernation au mode actif, l'intervalle étant sélectionné en fonction de la distance ; et déterminer de passer ou non au mode actif sur la base de l'intervalle déterminé.
 
11. Dispositif de suivi sans fil (122) selon la revendication 1, ledit au moins un capteur (250) comprenant un accéléromètre.
 
12. Procédé de fonctionnement d'un dispositif de suivi sans fil (122) comprenant
un dispositif de localisation (222), au moins un capteur (250) et un module de communication (226), le procédé comprenant :

le placement du dispositif de suivi sans fil (122) dans le mode hibernation;

la génération d'un signal de capteur (282) par le au moins un capteur (250),

le signal de capteur (282) représentantune condition ou une propriété associée au dispositif de suivi sans fil (122),

le passage du dispositif de suivi sans fil (122) vers un mode actif en réponse à un signal de capteur (282) indiquant un changement dépassant une première sensibilité correspondant à un premier événement externe, ledit mode actif consommant plus de puissance que le mode hibernation ;

l'augmentation de la sensibilité du au moins capteur (250) en vue de la détection d'un événement à une seconde sensibilité pendant que le dispositif de suivi sans fil (122) est dans le mode actif ;

la détermination d'un emplacement géographique du dispositif de suivi sans fil (122) par le dispositif de localisation (222) ;

la génération d'un message indiquant l'emplacement géographique, la condition ou la propriété associée au dispositif de suivi sans fil (122) ;

l'envoi du message par l'intermédiaire d'un réseau sans fil par le module de communication (226) ; et

le maintien du dispositif de suivi sans fil (122) dans le mode actif en réponse à la réception d'un signal de capteur (282) indiquant un changement dépassant la second sensibilité correspondant à un second événement externe ;

ledit dispositif de localisation (222) et ledit module de communication (226) pouvant fonctionner dans le mode actif mais pas dans le mode hibernation et étant actionnés par intermittence en mode actif.


 
13. Procédé selon la revendication 12, dans le mode hibernation, l'un des deux dispositif de commandes étant coupé.
 
14. Procédé selon la revendication 12, ledit emplacement étant déterminé à l'aide d'un système de positionnement par satellites, GPS.
 
15. Procédé selon la revendication 14, comprenant en outre la réception de données d'éphémérides en provenance d'un serveur distant par l'intermédiaire du réseau sans fil.
 
16. Procédé selon la revendication 12, comprenant en outre :

le calcul d'une heure d'arrivée estimée du dispositif de suivi sans fil dans une région géographique où le message ne doit pas être envoyé par l'intermédiaire du réseau sans fil ;

la détermination d'un intervalle pour faire passer le dispositif de suivi sans fil du mode d'hibernation au mode actif ; et

la détermination du passage ou non au mode actif sur la base de l'intervalle déterminé, ledit intervalle étant déterminé sur la base de la proximité d'une barrière géographique (410).


 
17. Procédé selon la revendication 16, ledit intervalle étant raccourci lorsque le dispositif de suivi sans fil s'approche de la barrière géographique (410).
 
18. Procédé selon la revendication 12, ledit signal de capteur (282) étant généré par un accéléromètre (250).
 
19. Support de stockage non transitoire lisible par ordinateur structuré pour stocker des instructions exécutables par un processeur dans un dispositif de suivi sans fil (122) comprenant un dispositif de localisation (222), au moins un capteur (250) et un module de communication (226),
les instructions, lorsqu'elles sont exécutées, amenant le processeur à :

placer le dispositif de suivi sans fil (122) dans un mode hibernation durant une durée prédéfinie ;

générer un signal de capteur (282) par le au moins un capteur (250),

le signal de capteur (282) représentantune condition ou une propriété associée au dispositif de suivi sans fil ;

faire passer le dispositif de suivi sans fil (122) vers un mode actif en réponse à un signal de capteur (282) indiquant un changement dépassant une première sensibilité correspondant à un premier événement externe, le mode actif consommant plus d'énergie que le mode hibernation ;

augmenter la sensibilité du au moins un capteur (250) pour détecter un événement à une seconde sensibilité

pendant que le dispositif de suivi sans fil (122) est dans le mode actif ;

déterminer un emplacement géographique du dispositif de suivi sans fil (122) par le dispositif de localisation (222) ;

générer un message indiquant l'emplacement géographique, la condition ou la propriété associée au dispositif de suivi sans fil ;

envoyer le message par l'intermédiaire d'un réseau sans fil par le module de communication (226) ; et

maintenir le dispositif de suivi sans fil (122) dans le mode actif en réponse à la réception d'un signal de capteur (282) indiquant un changement dépassant la second sensibilité correspondant à un second événement externe ;

ledit dispositif de localisation (222) et ledit module de communication (226) pouvant fonctionner dans le mode actif mais pas dans le mode hibernation et étant actionnés par intermittence en mode actif.


 




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Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description