Methods and apparatuses for transmitting and receiving position reference signals

• US 8,606,220 B2
• Filed: 03/27/2012
• Issued: 12/10/2013
• Est. Priority Date: 03/28/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Soliman, Samir S., Gaal, Peter
• Primary Examiner(s): Akonai, Olumide T Ajibade
• Assistant Examiner(s): Peaches, Randy
• Application Number:
  US13/431,788
• Publication Number:
  US 20120231803A1
• Time in Patent Office: 623 Days
• Field of Search: 455/404.2
• US Class Current: 455/404.2
• CPC Class Codes: G01S 1/0423 Mounting or deployment thereof
• CPC Class Codes: G01S 1/0428 Signal details
• CPC Class Codes: G01S 19/12 wherein the cooperating elements are telecommunication base stations
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/0226 Transmitters
• CPC Class Codes: H04B 7/2687 Inter base stations synchronisation
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A method and apparatus for generating and use of a position location reference signal that allows a receiver to receive position location signals from relatively weak signal generators when in the presence of a strong signal source. The position location reference signals from multiple sources can be synchronized to occur within a scheduled time slot of a time division multiplexed communication system. During the scheduled time slot, each signal source can configure a transmission that includes a media access control address that corresponds to a value reserved for position location signals. Each signal source also configures the transmission to include a position location reference signal that corresponds to the signal source. The position location signals from each of the signal sources is positioned to occur at a time within the data portion of the scheduled time slot that no neighboring signal source transmits its corresponding position location signal.

Claims

1. A method comprising:

determining scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots; and

transmitting the scheduling information,

wherein ranging information associated with the transmission of the position location information is determined for a user terminal based on the scheduling information.

2. The method of claim 1 wherein the determining further comprises determining the scheduling information for multiple position location signal sources.

3. The method of claim 2 wherein the determining further comprises assigning respective time offsets to the first intervals and the second intervals for each of the position location signal sources.

4. The method of claim 3 wherein the determining further comprises assigning the time offsets according to a sub-slot reuse algorithm.

5. The method of claim 3 further comprising transmitting a system time reference, wherein the time offsets are assigned relative to the system time reference.

6. The method of claim 1, wherein at least a portion of the method is performed by a processor.

7. A method comprising:

receiving scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots;

processing the position reference signal according to the scheduling information; and

determining ranging information based on the transmission of the position location information.

8. The method of claim 7 wherein receiving the scheduling information further comprises receiving the scheduling information as assigned to multiple position location signal sources.

9. The method of claim 8 further comprising identifying time offsets assigned to the first intervals and the second intervals for each of the position location signal sources based at least in part on the scheduling information.

10. The method of claim 9 further comprising receiving a system time reference, wherein the time offsets are assigned relative to the system time reference.

11. The method of claim 7 wherein the scheduling information is in response to a request for position location information.

12. The method of claim 7, wherein at least a portion of the method is performed by a processor.

13. An apparatus comprising:

a processor configured to determine scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots; and

a transmitter communicatively coupled to the processor and configured to transmit the scheduling information,

wherein ranging information associated with the transmission of the position location information is determined for a user terminal based on the scheduling information.

14. The apparatus of claim 13 wherein the processor is further configured to determine the scheduling information for multiple position location signal sources by assigning respective time offsets to the first intervals and the second intervals for each of the position location signal sources.

15. The apparatus of claim 14 wherein the processor is further configured to assign the time offsets according to a sub-slot reuse algorithm.

16. The apparatus of claim 14 wherein:

the transmitter is further configured to transmit a system time reference; and

the time offsets are assigned relative to the system time reference.

17. An apparatus comprising:

a receiver configured to receive scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots, and to receive the position location information; and

a processor communicatively coupled to the receiver and configured to process the position reference signal according to the scheduling information, the processor being configured to determine ranging information based on the transmission of the position location information.

18. The apparatus of claim 17 wherein the receiver is further configured to identify time offsets assigned to the first intervals and the second intervals for each of a plurality of position location signal sources based at least in part on the scheduling information.

19. The apparatus of claim 18 wherein the receiver is further configured to receive a system time reference, and wherein the time offsets are assigned relative to the system time reference.

20. The apparatus of claim 17 wherein the scheduling information is in response to a request for position location information.

21. An apparatus comprising:

means for determining scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots; and

means for transmitting the scheduling information,

wherein ranging information associated with the transmission of the position location information is determined for a user terminal based on the scheduling information.

22. An apparatus comprising:

means for receiving scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots;

means for processing the position reference signal according to the scheduling information; and

means for determining ranging information based on the transmission of the position location information.

23. A non-transitory processor-readable storage medium comprising processor-executable instructions configured to cause a processor to:

determine scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots; and

transmit the scheduling information,

wherein ranging information associated with the transmission of the position location information is determined for a user terminal based on the scheduling information.

24. A non-transitory processor-readable storage medium comprising processor-executable instructions configured to cause a processor to:

receive scheduling information for a transmission of position location information, the scheduling information indicating a timing of first intervals of the transmission assigned to a position reference signal and second intervals of the transmission assigned to blank sub-slots;

process the position reference signal according to the scheduling information; and

determine ranging information based on the transmission of the position location information.