METHODS AND SYSTEMS FOR PROVIDING ENHANCED POSITION LOCATION IN WIRELESS COMMUNICATIONS

• US 20140269638A1
• Filed: 05/28/2014
• Published: 09/18/2014
• Est. Priority Date: 12/20/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Black, Peter John, Grob, Matthew Stuart
• Granted Patent: US 9,955,476 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: G01S 5/02216 Timing or synchronisation of the receivers
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/14 using user query or user detection
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

Embodiments disclosed herein relate to methods and systems for providing improved position-location (e.g., time-of-arrival) measurement and enhanced position location in wireless communication systems. In an embodiment, an access point may replace information (e.g., data) transmission by a “known” transmission (or “reference transmission”) at a predetermined time known to access terminals in the corresponding sectors. The access terminals may use the received reference transmission to perform a position-location measurement, and report back the measured information. The access point may also send a reference transmission on demand, e.g., in response to a request from an access terminal in need for a location-based service.

Claims

1. A method for wireless communications, comprising:

generating a pilot signal and a reference signal, the reference signal comprising a sequence of symbols known to an access terminal; and

transmitting the pilot signal and the reference signal in a time slot.

2. The method of claim 1, further comprising time-division-multiplexing the pilot signal and the reference signal in the time slot.

3. The method of claim 2, wherein the time slot includes a pilot channel time-division-multiplexed with a traffic channel, the pilot channel carrying the pilot signal and the traffic channel carrying the reference signal.

4. The method of claim 3, wherein the reference signal substantially occupies the traffic channel.

5. The method of claim 2, further comprising transmitting the reference signal at a maximum power.

6. The method of claim 1, further comprising code-division-multiplexing the pilot signal and the reference signal in the time slot

7. The method of claim 1, wherein the reference signal is substantially identical to the pilot signal.

8. The method of claim 1, wherein the reference signal includes a sector ID.

9. The method of claim 1, wherein the reference signal is transmitted in accordance with a predetermined schedule.

10. The method of claim 1, wherein the reference signal is transmitted in response to a request from the access terminal.

11. The method of claim 1, further comprising transmitting the time slot on a subset of multiple carriers.

12. A communication structure transmitted on a carrier wave, comprising:

a pilot channel carrying a pilot signal; and

a traffic channel carrying a reference signal, the reference signal comprising a sequence of symbols known to an access terminal.

13. The communication structure of claim 12, wherein the pilot channel is time-division-multiplexed with the traffic channel.

14. The communication structure of claim 12, wherein the reference signal is substantially identical to the pilot signal.

15. The communication structure of claim 12, wherein the reference signal includes a sector identifier.

16. An apparatus adapted for wireless communications, comprising:

means for generating a pilot signal and a reference signal, the reference signal comprising a sequence of symbols known to an access terminal; and

means for transmitting the pilot signal and the reference signal in a time slot.

17. The apparatus of claim 16, further comprising means for multiplexing the pilot signal and the reference signal in the time slot in one of a time-division-multiplexed format and a code-division-multiplexed format.

18. The apparatus of claim 16, wherein the time slot includes a pilot channel and a traffic channel, wherein the pilot channel carries the pilot signal and the traffic channel carries the reference signal.

19. The apparatus of claim 16, wherein the reference signal is transmitted in accordance with a predetermined schedule.

20. The apparatus of claim 16, wherein the reference signal is transmitted in response to a request from the access terminal.

21. The apparatus of claim 16, wherein the means for transmitting is further configured to transmit the time slot on a subset of multiple carriers.