Aided location communication system

• US 7,970,412 B2
• Filed: 07/20/2005
• Issued: 06/28/2011
• Est. Priority Date: 05/18/2000
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: SIRF Technology Incorporated (Qualcomm, Inc.)
• Inventors: Vantalon, Nicolas Patrick, Chadha, Kanwar, Schmidt, Kurt Christian, Turetzky, Gregory B., Zhang, Gengsheng, Garin, Lionel Jacques, Peng, Leon Kuo-Liang, Pande, Ashutosh
• Primary Examiner(s): DESIR, PIERRE LOUIS
• Application Number:
  US11/185,533
• Publication Number:
  US 20060038719A1
• Time in Patent Office: 2,169 Days
• Field of Search: 455/456.1, 455/456.6, 455/12.1, 455/13.2, 455/440, 701/213, 701/200, 342/357.12, 342/357.06, 342/357.1, 342/357.05, 342/357.03, 342/357.09, 342/457, 342/387, 342/352
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/17 Emergency applications
• CPC Class Codes: G01S 19/26 involving a sensor measurement for aiding acquisition or tracking
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile

Abstract

An Aided Location Communication System (“ALCS”) is described that may include a geolocation server and a wireless communication device having a GPS section where the GPS receiver section is capable of being selectively switched between a standalone mode and at least one other mode for determining a geolocation of the wireless communications device. An Aided Location Communication Device (“ALCD”) is also described. The ALCD includes a position-determination section having a GPS receiver and a communication section where the position-determination section is selectively switchable between a GPS-standalone mode and at least one other mode for determining a geolocation of the ALCD.

Claims

1. An Aided Location Communication System (“

ALCS”

), comprising;

a geolocation server; and

an Aided Location Communication Device (“

ALCD”

) including;

a communication section having a host processor in signal communication with the geolocation server,

a position-determination section having a GPS-engine, which acquires and tracks a GPS signal from a GPS satellite, and is in communication with the host processor,

wherein the host processor is capable of selectively switching from;

a first position-determination mode for determining a geolocation of the ALCD, to

a second position-determination mode for determining the geolocation of the ALCD in response to the host processor determining that the geolocation has been determined in the first position determination mode.

2. The ALCS of claim 1, wherein the selective switching occurs substantially simultaneously with the determination of the geolocation of the ALCD.

3. The ALCS of claim 1, wherein the geolocation server receives at least one GPS-signal from at least one GPS satellite.

4. The ALCS of claim 1, wherein the communication section is capable of selectively sending the determined geolocation of the ALCD to the geolocation server.

5. The ALCS of claim 1, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

6. The ALCS of claim 1, wherein the first mode position-determination mode is selected from a group consisting of:

GPS-standalone mode;

a GPS-autonomous mode;

a GPS-network aided mode;

a GPS-network centric mode;

a network-based mode;

a reverse-aiding mode; and

an augmented-autonomous mode.

7. The ALCS of claim 6, wherein the second position-determination mode is selected from a group consisting of:

the GPS-standalone mode;

the GPS-autonomous mode;

the GPS-network aided mode;

the GPS-network centric mode;

the network-based mode;

the reverse-aiding mode; and

the augmented-autonomous mode.

8. The ALCS of claim 7, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

9. The ALCS of claim 7, wherein the communication section is capable of selectively sending the determined geolocation of the ALCD to the geolocation server.

10. The ALCS of claim 9, wherein the communication section includes a wireless receiver.

11. The ALCS of claim 10, wherein the selective switching of the position determination section is performed automatically by the ALCD.

12. The ALCS of claim 11, wherein the selective switching of the position determination section is performed automatically by the communication section.

13. The ALCS of claim 6 or 7, wherein the augmented-autonomous mode utilizes a network resource selected from a group consisting of:

a computer network;

a communication network; and

a wireless network.

14. The ALCS of claim 13, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

15. The ALCS of claim 14, wherein the wireless network is a Bluetooth wireless network.

16. The ALCS of claim 14, wherein the wireless network is an IEEE 802.11 wireless network.

17. The ALCS of claim 6 or 7, wherein the augmented-autonomous mode utilizes an external device that is capable of transmitting augmented-aiding information.

18. The ALCS of claim 17, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

19. The ALCS of claim 18, wherein the external device utilizes a wireless transmission to transmit the augmented-aiding information.

20. The ALCS of claim 19, wherein the wireless transmission includes a Bluetooth transmission.

21. The ALCS of claim 19, wherein the wireless transmission includes an IEEE 802.11 transmission.

22. The ALCS of claim 19, wherein the external device includes a GPS wireless re-radiator.

23. The ALCS of claim 18, wherein the external device utilizes a non wireless transmission to transmit the augmented-aiding information.

24. The ALCS of claim 23, wherein the non-wireless transmission includes a serial connection.

25. The ALCS of claim 23, wherein the non-wireless transmission includes an Ethernet connection.

26. The ALCS of claim 23, wherein the non-wireless transmission includes an electrical connection.

27. The ALCS of claim 18, wherein the augmented-aiding information includes the location information for the external device.

28. The ALCS of claim 18, wherein the augmented-aiding information includes ephemeris data for the GPS satellites.

29. The ALCS of claim 7, wherein the ALCD operating in the network-based mode utilizes transmitters within an external communication system to determine the geolocation of the ALCD.

30. The ALCS of claim 29, wherein the ALCD utilizes a Time Difference of Arrival (“

TDOA”

) technique to determine the geolocation of the ALCD.

31. The ALCS of claim 30, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

32. The ALCS of claim 7, wherein the ALCD operating in the reverse-aiding mode monitors the ALCS.

33. The ALCS of claim 32, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

34. The ALCS of claim 33, wherein the ALCD operating in the reverse-aiding mode monitors the ALCS for utilization in power management of the ALCS.

35. The ALCS of claim 34, where the power management includes varying the characteristics of an antenna beam transmitted from a basestation to the ALCD, wherein the basestation is within the ALCS.

36. The ALCS of claim 33, wherein the ALCD operating in the reverse-aiding mode monitors the ALCS for utilization in cell planning of the ALCS.

37. The ALCS of claim 33, wherein the ALCD sends the geolocation server the determined geolocation of the ALCD along with wireless network monitoring information.

38. The ALCS of claim 37, wherein the wireless network monitoring information includes wireless signal strength of the wireless network at the geolocation of the ALCD.

39. The ALCS of claim 33, wherein the ALCD sends the geolocation server the geolocation, velocity and heading of the ALCD within the wireless network.

40. The ALCS of claim 33, wherein the ALCD, operating in the reverse-aiding mode, provides the geolocation server with redundant time and frequency reference information measured at the ALCD.

41. The ALCS of claim 40, wherein the ALCS models the wireless network time offset and frequency drift from the redundant time and frequency reference information measured at the ALCD.

42. The ALCS of claim 33, wherein the ALCD sends the geolocation server the multipath information measured at the ALCD.

43. The ALCS of claim 42, wherein the ALCS models the wireless network multipath characteristics from the measured multipath information from the ALCD.

44. The ALCS of claim 33, wherein the ALCS aligns the phase locked loop (“

PLL”

) of the ALCD wireless tracking loops.

45. The ALCS of claim 7, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

46. The ALCS of claim 45, wherein the ALCD operating in the reverse-aiding mode utilizes direct GPS aiding from a second ALCD within the ALCS without utilizing the geolocation server.

47. The ALCS of claim 45, wherein the ALCD operating in the reverse aiding mode utilizes space-domain multiplexing (“

SDM”

) to increase the frequency capacity within a cell of the ALCS.

48. The ALCS of claim 45, wherein the position-determination section switches between the first position-determination mode and the second position determination mode when a predetermined event occurs.

49. The ALCS of claim 48, wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

50. The ALCS of claim 49, wherein the first position-determination mode is the GPS-standalone mode and the second position-determination mode is selected from a group consisting of:

the GPS-autonomous mode;

the GPS-network aided mode;

the GPS-network centric mode;

the network-based mode;

the reverse-aiding mode; and

the augmented-autonomous mode.

51. The ALCS of claim 50, wherein the selective switching of the position-determination section switches the position-determination section from the second position-determination mode to the GPS-standalone mode.

52. The ALCS of claim 50, wherein the second position-determination mode is the GPS-network aided mode.

53. The ALCS of claim 50, wherein the second position-determination mode is the reverse-aiding mode.

54. The ALCS of claim 53, wherein the ALCD is capable of receiving information from a second source.

55. The ALCS of claim 54, wherein the second source is selected from a group consisting of:

a Bluetooth network;

a specialized mobile radio (“

SMR”

) network;

a personal communication system (“

PCS”

) network;

a non-wireless local area network;

a wireless local area network;

an infrared network;

a paging network;

a two-way paging network; and

an FM broadcast network.

56. The ALCS of claim 55, wherein the wireless local area network is an IEEE 802.11 wireless network.

57. The ALCS of claim 55, wherein the geolocation of the ALCD is determined utilizing GPS-signals from at least one GPS satellite and the information from the second source.

58. The ALCS of claim 48, wherein the predetermined event is a lapse of a predetermined amount of time without acquiring at least one GPS satellite signal.

59. The ALCS of claim 58, wherein the predetermined event occurs within a thirty second time window centered on a time of determination of the geolocation of the ALCD.

60. The ALCS of claim 45, wherein

the communication section is capable of selectively sending the determined geolocation of the ALCD to the geolocation server,

the communication section includes a wireless receiver, and

the communication section periodically transmits a frequency reference message to the position-determination section.

61. The ALCS of claim 60, wherein the frequency reference message steers a call processing clock onto a basestation clock, where the call processing clock is part of the communication section and the basestation clock is in signal communication with the geolocation server.

62. The ALCS of claim 60, wherein the frequency reference message includes an error between a call processing clock and a basestation clock, where the call processing clock is part of the communication section and the basestation clock is in signal communication with the geolocation server.

63. The ALCS of claim 62, wherein a GPS clock in the position-determination section is periodically compared to the call processing clock to determine a frequency offset of the GPS clock.

64. The ALCS of claim 63, wherein the periodic transmission of the frequency reference message and the periodic comparison of the GPS clock to the call processing clock have the same period.

65. The ALCS of claim 64, wherein the position-determination section switches between the first position-determination mode and the second position determination mode when a predetermined event occurs.

66. The ALCS of claim 65, wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

67. The ALCS of claim 66, wherein the selective switching of the position-determination section switches the position-determination section from the first position-determination mode to the GPS-standalone mode.

68. An Aided Location Communication Device (“

ALCD”

), the ALCD comprising;

a communication section having a host processor for communicating with a wireless communications network; and

a position-determination section having a GPS-engine, which acquires and tracks a GPS signal from a GPS satellite, and communicates with the host processor,

wherein the host processor is capable of selectively switching from;

a first mode position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD in response to the host processor determining that the geolocation has been determined in the first position determination mode.

69. The ALCS of claim 68, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

70. The ALCD of claim 69, wherein the first mode position-determination mode is selected from a group consisting of:

GPS-standalone mode;

a GPS-autonomous mode;

a GPS-network aided mode;

a GPS-network centric mode;

a network-based mode;

a reverse-aiding mode; and

an augmented-autonomous mode.

71. The ALCD of claim 70, wherein the at least one other position-determination mode is selected from a group consisting of:

the GPS-standalone mode;

the GPS-autonomous mode;

the GPS-network aided mode;

the GPS-network centric mode;

the network-based mode;

the reverse-aiding mode; and

the augmented-autonomous mode.

72. The ALCD of claim 71, wherein the selective switching occurs substantially simultaneously with the determination of a geolocation of the ALCD.

73. The ALCD of claim 71, wherein the communication section is capable of selectively sending a determined geolocation of the ALCD to a geolocation server.

74. The ALCD of claim 73, wherein the communication section includes a wireless receiver.

75. The ALCD of claim 70 or 71, wherein the augmented-autonomous mode utilizes a network resource selected from a group consisting of:

a computer network;

a communication network; and

a wireless network.

76. The ALCD of claim 75, wherein the wireless network is a Bluetooth wireless network.

77. The ALCD of claim 76, wherein the wireless network is an IEEE 802.11 wireless network.

78. The ALCD of claim 70 or 71, wherein the augmented-autonomous mode utilizes an external device that is capable of transmitting augmented-aiding information.

79. The ALCD of claim 78, wherein the external device utilizes a wireless transmission to transmit the augmented-aiding information.

80. The ALCD of claim 79, wherein the wireless transmission includes a Bluetooth transmission.

81. The ALCD of claim 79, wherein the wireless transmission includes an IEEE 802.11 transmission.

82. The ALCD of claim 79, wherein the external device includes a GPS wireless re-radiator.

83. The ALCD of claim 78, wherein the external device utilizes a non-wireless transmission to transmit the augmented-aiding information.

84. The ALCD of claim 78, wherein the augmented-aiding information includes the location information for the external device.

85. The ALCD of claim 84, wherein the augmented-aiding information includes ephemeris data for the GPS satellites.

86. The ALCD of claim 69 or 70, wherein the position-determination section switches between the GPS-standalone mode and the at least one other mode when a predetermined event occurs.

87. The ALCD of claim 86, wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

88. The ALCD of claim 87, wherein the selective switching of the GPS receiver switches the position-determination section from the at least one other position-determination mode to the GPS-standalone mode.

89. The ALCD of claim 88, wherein the ALCD is capable of receiving information from a second source.

90. The ALCD of claim 89, wherein the second source is selected from a group consisting of:

a Bluetooth network;

a specialized mobile radio (“

SMR”

) network;

a personal communication system (“

PCS”

) network;

a non-wireless local area network;

a wireless local area network;

an infrared network;

a paging network;

a two-way paging network; and

an FM broadcast network.

91. The ALCD of claim 90, wherein the wireless local area network is an IEEE 802.11 wireless network.

92. The ALCD of claim 90, wherein the geolocation of the ALCD is determined utilizing GPS-signals from at least one GPS satellite and the information from the second source.

93. An Aided Location Communication Device (“

ALCD”

), the ALCD comprising;

a host processor for communicating with a wireless communications network; and

a position-determination section having a GPS-engine, which acquires and tracks a GPS signal from a GPS satellite, communicates with the host processor,

wherein the communicating means is capable of selectively switching from;

a first mode position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD, in response to the host processor determining that the geolocation has been determined in the first position determination mode.

94. The ALCD of claim 93, wherein the GPS-engine is a GPS tracker capable of receiving GPS signals and producing GPS pseudo-range signals corresponding to the received GPS signals.

95. The ALCD of claim 94 wherein the first mode position-determination mode is selected from a group consisting of:

GPS-standalone mode;

a GPS-autonomous mode;

a GPS-network aided mode;

a GPS-network centric mode;

a network-based mode;

a reverse-aiding mode; and

an augmented-autonomous mode.

96. The ALCD of claim 95 wherein the at least one other position

determination mode is selected from a group consisting of:

the GPS-standalone mode;

the GPS-autonomous mode;

the GPS-network aided mode;

the GPS-network centric mode;

network-based mode;

the reverse-aiding mode; and

the augmented-autonomous mode.

97. An Aided Location Communication System (“

ALCS”

), comprising;

an Aided Location Communication Device (“

ALCD”

), including

a communication section having a host processor;

a GPS section for acquiring and tracking a GPS signal from a GPS satellite, and communicating with the host processor, and

a strategy selector, external to and coupled to the GPS section, that determines a positioning strategy based upon a state of the GPS section, wherein the strategy selector is capable of selectively switching from;

a first position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD, in response to the host processor determining that the geolocation has been determined in the first position determination mode

wherein the host processor is coupled to the GPS section and the strategy selector, for transmitting and receiving data to and from a geolocation server; and

a geolocation server, which communicates with the communications section of the ALCD via a communications network, including

an aiding data generation section for forming location aiding data; and

a communication control section for transmitting data to and receiving data from the ALCD.

98. An Aided Location Communication Device (“

ALCD”

) tracking at least one GPS satellite, comprising;

a bus structure,

a Central Processing Unit (CPU) core comprising

a host microprocessor, coupled to the bus structure;

a cache memory coupled to the bus structure for storing software code;

a random access memory, coupled to the bus structure, for storing data;

a read only memory, coupled to the bus structure, for storing a boot program; and

a GPS engine, which acquires and tracks a GPS signal from the GPS satellite, and communicates with the host microprocessor, the GPS engine comprising

a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals, wherein the GPS architecture can couple to at least two different protocol interfaces via the bus structure,

wherein the host microprocessor is capable of selectively switching from;

a first position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD in response to the host processor determining that the geolocation has been determined in the first position determination mode.

99. An Aided Location Communication Device (“

ALCD”

) for tracking at least one GPS satellite, comprising;

a bus structure,

a Central Processing Unit (CPU) core comprising;

a host microprocessor, coupled to the bus structure;

a cache memory coupled to the bus structure for storing software code;

a random access memory, coupled to the bus structure, for storing data and for storing autonomous code used for tracking at least one GPS satellite;

a read only memory, coupled to the bus structure, for storing a boot program; and

a GPS engine, which acquires and tracks a GPS signal from the GPS satellite, and communicates with the host microprocessor, the GPS engine comprising;

a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals, wherein the GPS engine can selectively use the stored autonomous code for tracking at least one GPS satellite,

wherein the host microprocessor is capable of selectively switching from;

a first position-determination mode for determining a geolocation of the ALCD to

at least one other position-determination mode for determining the geolocation of the ALCD, in response to the host processor determining that the geolocation has been determined in the first position determination mode.

100. An Aided Location Communication Device (“

ALCD”

) for tracking at least one GPS satellite, comprising;

a bus structure,

a Central Processing Unit (CPU) core comprising

a host microprocessor, coupled to the bus structure;

a cache memory coupled to the bus structure for storing software code;

a random access memory, coupled to the bus structure, for storing data;

a read only memory, coupled to the bus structure, for storing a boot program; and

a GPS engine, which acquires and tracks a GPS signal from the GPS satellite, and communicates with the host microprocessor, the GPS engine comprising;

a receiving, tracking, and demodulating engine for GPS and Wide Area Augmentation Service (WAAS) signals, wherein the GPS architecture can couple, via the bus structure, to at least two different protocol interfaces, and wherein the protocol interface is selected by the GPS architecture automatically,

wherein the host microprocessor is capable of selectively switching from;

a first position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD, in response to the host processor determining that the geolocation has been determined in the first position determination mode.

101. A method for determining the geolocation of an Aided Location Communication Device (“

ALCD”

), having a position-determination section and a communication section, within an Aided Location Communication System (“

ALCS”

), the method comprising;

acquiring and tracking, by a GPS engine, at least one GPS-signal, from at least one GPS satellite, and communicating with a host processor,

switching, by the host processor, from;

a first position-determination mode for determining a geolocation of the ALCD, to

at least one other position-determination mode for determining the geolocation of the ALCD, in response to the host processor determining that the geolocation has been determined in the first position determination mode.

102. The method of claim 101 wherein the first position-determination mode is selected from a group consisting of:

a GPS-standalone mode;

a GPS-autonomous mode;

a GPS-network aided mode;

a GPS-network centric mode;

a network-based mode;

a reverse-aiding mode; and

an augmented-autonomous mode.

103. The method of claim 102 wherein the at least one other position determination mode is selected from a group consisting of:

the GPS-standalone mode;

the GPS-autonomous mode;

the GPS-network aided mode;

the GPS-network centric mode;

the network-based mode;

the reverse-aiding mode; and

the augmented-autonomous mode.

104. The method of claim 103, wherein the geolocation of ALCD is determined utilizing the selected at least one other position-determination mode immediately after switching into the selected at least one other position-determination mode.

105. The method of claim 103, further including selectively sending the determined geolocation of the ALCD to a geolocation server in the ALCS.

106. The method of claim 105, wherein the determining the geolocation is performed by the ALCD.

107. The method of claim 106, wherein the position-determination utilizes a GPS-engine and the communication section determines the geolocation of the ALCD.

108. The method of claim 106, wherein the selective sending of the determined geolocation of the ALCD is performed by the ALCD, and the geolocation is sent from the ALCD to the geolocation server.

109. The method of claim 106, wherein selectively switching includes automatically selectively switching the ALCD.

110. The method of claim 103, wherein the augmented-autonomous mode is selected further including receiving augmented-mode information from a network resource selected from a group consisting of:

a computer network;

a communication network; and

a wireless network.

111. The method of claim 110, wherein the wireless network is a Bluetooth wireless network.

112. The method of claim 110, wherein the wireless network is an IEEE 802.11 wireless network.

113. The method of claim 103, wherein selecting the augmented autonomous mode further including receiving augmented-aiding information transmitted from an external device.

114. The method of claim 113, wherein the augmented-aiding information is received via a wireless transmission.

115. The method of claim 114, wherein the augmented-aiding information is received via a Bluetooth transmission.

116. The method of claim 114, wherein the augmented-aiding information is received via an IEEE 802.11 transmission.

117. The method of claim 113, wherein receiving augmented-aiding information transmitted from an external device includes receiving the augmented-aiding information transmitted from a stationary object.

118. The method of claim 117, wherein receiving the augmented-aiding information transmitted from a stationary object includes receiving the augmented-aiding information transmitted from an EXIT sign.

119. The method of claim 117, wherein receiving the augmented-aiding information transmitted from a stationary object includes receiving the augmented-aiding information transmitted from a traffic sign.

120. The method of claim 117, wherein receiving the augmented-aiding information transmitted from a stationary object includes receiving the augmented-aiding information transmitted from a light post.

121. The method of claim 113, wherein the augmented-autonomous mode includes receiving the augmented-aiding information transmitted from an external device that includes GPS re-radiated aiding information.

122. The method of claim 113, wherein the augmented-aiding information is received via a non-wireless transmission.

123. The method of claim 122, wherein the augmented-aiding information is a received via a serial connection.

124. The method of claim 122, wherein the augmented-autonomous mode includes receiving the augmented-aiding information via an Ethernet connection.

125. The method of claim 122, wherein the augmented-autonomous mode includes receiving the augmented-aiding information via an electrical connection.

126. The method of claim 125, wherein the augmented-autonomous mode includes receiving the augmented-aiding information from a battery charger within the external device.

127. The method of claim 103 wherein

the augmented-autonomous mode is selected further including receiving augmented-mode information from a network resource selected from a group consisting of:

a computer network;

a communication network; and

a wireless network, and

wherein receiving the augmented-aiding information includes receiving ephemeris data for the GPS satellites.

128. The method of claim 127 wherein selecting the augmented autonomous mode further including receiving the augmented-aiding information transmitted from an external device.

129. The method of claim 128 wherein receiving the augmented-aiding information transmitted from an external device includes receiving the location information for the external device.

130. The method of claim 103 wherein the ALCD selectively switches between the GPS-standalone mode and the at least one other mode when a predetermined event occurs.

131. The method of claim 130 wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

132. The method of claim 130 further including selectively switching from the at least one other position-determination mode to the GPS-standalone mode.

133. The method of claim 132 wherein the ALCD receives information from a second source.

134. The method of claim 133 wherein the second source is selected from a group consisting of

Bluetooth network;

a specialized mobile radio (“

SMR”

) network;

a personal communication system (“

PCS”

) network;

a non-wireless local area network;

a wireless local area network;

an infrared network;

a paging network;

a two-way paging network; and

an FM broadcast network.

135. The method of claim 134 wherein the wireless local area network is an IEEE 802.11 wireless network.

136. The method of claim 135 wherein the geolocation of the ALCD is determined utilizing GPS-signals from at least one GPS satellite and the information from the second source.

137. The method of claim 130 further including selectively displaying the determined geolocation of the ALCD on the ALCD.