Information transfer in a multi-mode global positioning system used with wireless networks

• US 6,427,120 B1
• Filed: 02/28/2001
• Issued: 07/30/2002
• Est. Priority Date: 08/14/2000
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: SIRF Technology Incorporated (Qualcomm, Inc.)
• Inventors: Garin, Lionel Jacques, Pande, Ashutosh, Chadha, Kanwar, Turetzky, Gregory Bret
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US09/795,871
• Time in Patent Office: 517 Days
• Field of Search: 701/213, 340/989, 342/357.09, 342/357.13, 342/352, 342/356
• US Class Current: 701/213
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/32 Multimode operation in a single same satellite system, e.g. GPS L1/L2
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 5/0009 Transmission of position information to remote stations involving assistance data G01S5/0236
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

The present invention discloses a GPS system that can operate in different modes depending on the network facilities and bandwidth available, the GPS information that can be acquired, or user or system requirements. The modes comprise standalone mode, where a mobile communications device computes the position of the device, an autonomous mode, where the mobile communications device transmits the computed position to a server, application, or PSAP in a communications network, a network aided mode, where the network aides the mobile communications device in determining the position of the device, a network based mode, and other modes.

Claims

1. A geolocation system, comprising:

a geolocation server, wherein the geolocation server receives at least one signal from at least one GPS satellite; and

a wireless communications device, comprising a GPS receiver section, the GPS receiver being selectively switchable between a standalone mode and at least one other mode for determining a geolocation of the wireless communications device, wherein the at least one other mode is selected from a group comprising an autonomous mode, a network aided mode, a network centric mode, and a reverse aiding mode, and the wireless communication device can selectively send the determined geolocation of the wireless communication device to the geolocation server, wherein the wireless communications device periodically transmits a frequency reference message to the GPS receiver, wherein the frequency reference message comprises an error between a call processing clock and a base station clock, wherein a GPS clock in the GPS receiver is periodically compared to the call processing clock to determine a frequency offset of the GPS clock, and 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.

2. The geolocation system of claim 1, wherein the GPS receiver switches between the standalone mode and the at least one other mode when a predetermined event occurs.

3. The geolocation system of claim 2, wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

4. The geolocation system of claim 3, wherein the selective switching of the GPS receiver switches the receiver from the at least one other mode to standalone mode.

5. The geolocation system of claim 2, wherein the selective switching of the GPS receiver switches the receiver from standalone mode to the at least one other mode.

6. The geolocation system of claim 5, wherein the predetermined event is a lapse of a predetermined amount of time without acquiring at least one GPS satellite signal.

7. The geolocation system of claim 2, wherein the wireless communications device can receive information from a second source, the second source selected from a group comprising a bluetooth network, a Specialized Mobile Radio network, a Personal Communication System (PCS) network, a wireless Local Area Network, an infrared network, a paging network, a two-way paging network, and an FM broadcast network.

8. The geolocation system of claim 1, wherein the frequency reference message steers the call processing clock onto the base station clock, and the frequency reference message is only sent once to the wireless communications device.

9. The geolocation system of claim 8, wherein a GPS clock in the GPS receiver is periodically compared to the call processing clock to determine a frequency offset of the GPS clock.

10. The geolocation system of claim 9, wherein the GPS receiver switches between the standalone mode and the at least one other mode when a predetermined event occurs.

11. The geolocation system of claim 10, wherein the predetermined event is initial acquisition of at least one GPS satellite signal.

12. The geolocation system of claim 11, wherein the selective switching of the GPS receiver switches the receiver from the at least one other mode to standalone mode.

13. The geolocation system of claim 10, wherein the selective switching of the GPS receiver switches the receiver from standalone mode to the at least one other mode.

14. The geolocation system of claim 13, wherein the predetermined event is a lapse of a predetermined amount of time without acquiring at least one GPS satellite signal.

15. The geolocation system of claim 10, wherein the wireless communications device can receive information from a second source, the second source selected from a group comprising a bluetooth network, a Specialized Mobile Radio network, a Personal Communication System (PCS) network, a wireless Local Area Network, an infrared network, a paging network, a two-way paging network, and an FM broadcast network.