Apparatus and method for multi-sector velocity mobile velocity and doppler estimate for synchronous communication systems

• US 8,619,672 B2
• Filed: 06/09/2009
• Issued: 12/31/2013
• Est. Priority Date: 06/11/2008
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Tsai, Ming-Chang, Shah, Jigneshkumar P., Srinivas, Pillappakkam B.
• Primary Examiner(s): MIAN, OMER S
• Application Number:
  US12/481,186
• Publication Number:
  US 20090310505A1
• Time in Patent Office: 1,666 Days
• Field of Search: 370/252, 370/310.2, 370/328, 455/404.2, 455/456.1, 455/456.5, 367/90, 367/94
• US Class Current: 370/328
• CPC Class Codes: G01S 11/02 using radio waves G01S19/00 takes precedence
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location

Abstract

An apparatus and method for estimating velocity and Doppler frequency comprising acquiring a first plurality of time-of-arrival (TOA) measurements from a first plurality of base stations at a first time; acquiring a second and a third plurality of TOA measurements from a second and third plurality of base stations at a second time and a third time; determining a plurality of line-of-sight distance measurements using the first, second and third pluralities of TOA measurements; determining a plurality of velocity estimates and a plurality of angle of arrival (AOA) estimates, using the plurality of LOS distance measurements; determining a plurality of Doppler frequency estimates using the plurality of velocity estimates and the plurality of AOA estimates; and using a processor for determining an average Doppler frequency estimate over a plurality of sectors, wherein the first, second and third pluralities of TOA measurements are acquired over the plurality of sectors.

Claims

1. A method for estimating velocity and Doppler frequency in a wireless communication system, the method comprising:

using a receiver to acquire a first plurality of time-of-arrival (TOA) of forward link signals measurements from a first plurality of base stations at a first time;

using the receiver to acquire a second plurality of TOA measurements of forward link signals from a second plurality of base stations at a second time;

using the receiver to acquire a third plurality of TOA measurements of forward link signals from a third plurality of base stations at a third time;

determining a plurality of line-of-sight (LOS) distance measurements using the first, second and third pluralities of TOA measurements;

determining a plurality of velocity estimates and a plurality of angle of arrival (AOA) estimates, using the plurality of LOS distance measurements;

determining a plurality of Doppler frequency estimates using the plurality of velocity estimates and the plurality of AOA estimates; and

using a processor for determining an average Doppler frequency estimate and an average velocity over a plurality of sectors based on corresponding weighting factors, wherein the first, second and third pluralities of TOA measurements are acquired over the plurality of sectors;

wherein the first, second and third pluralities of TOA measurements are subject to a common constraint value based on which a forward link transmit time is constantly calibrated among the first, second and third pluralities of base stations; and

wherein the first plurality of base stations does not include base stations of the second and third pluralities of base stations, the second plurality of base stations does not include base stations of the first and third pluralities of base stations and the third plurality of base stations does not include base stations of the first and second pluralities of base stations.

2. The method of claim 1 wherein the first, second and third pluralities of base stations are synchronous with each other.

3. The method of claim 2 wherein the first, second and third pluralities of TOA measurements are synchronous and are derived from a Global Positioning System (GPS).

4. The method of claim 1, wherein the weighting factors are based on signal strengths of the forward link signals from the first, second and third pluralities of base stations.

5. The method of claim 1 wherein the receiver and the processor are components of the wireless communication system.

6. The method of claim 5 wherein the wireless communication system uses one of the following multiple access techniques:

Time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA) or orthogonal frequency division multiple access (OFDMA).

7. A mobile station comprising a processor and a memory, the memory containing program code executable by the processor for performing the following:

using a receiver to acquire a first plurality of time-of-arrival (TOA) measurements of forward link signals from a first plurality of base stations at a first time;

using the receiver to acquire a second plurality of TOA measurements of forward link signals from a second plurality of base stations at a second time;

using the receiver to acquire a third plurality of TOA measurements of forward link signals from a third plurality of base stations at a third time;

determining a plurality of line-of-sight (LOS) distance measurements using the first, second and third pluralities of TOA measurements;

determining a plurality of velocity estimates and a plurality of angle of arrival (AOA) estimates, using the plurality of LOS distance measurements;

determining a plurality of Doppler frequency estimates using the plurality of velocity estimates and the plurality of AOA estimates; and

using a processor for determining an average Doppler frequency estimate and an average velocity over a plurality of sectors based on corresponding weighting factors, wherein the first, second and third pluralities of TOA measurements are acquired over the plurality of sectors;

wherein the first, second and third pluralities of TOA measurements are subject to a common constraint value based on which a forward link transmit time is constantly calibrated among the first, second and third pluralities of base stations; and

wherein the first plurality of base stations does not include base stations of the second and third pluralities of base stations, the second plurality of base stations does not include base stations of the first and third pluralities of base stations and the third plurality of base stations does not include base stations of the first and second pluralities of base stations.

8. The mobile station of claim 7 wherein the first, second and third pluralities of base stations are synchronous with each other.

9. The mobile station of claim 8 wherein the first, second and third pluralities of TOA measurements are synchronous and are derived from a Global Positioning System (GPS).

10. The mobile station of claim 7 wherein the weighting factors are based on signal strengths of the forward link signals from with the first, second and third pluralities of base stations.

11. The mobile station of claim 7 wherein the receiver and the processor are components of the mobile station.

12. The mobile station of claim 11 wherein one of the following multiple access techniques are employed in acquiring the first, second and third pluralities of TOA measurements:

Time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA) or orthogonal frequency division multiple access (OFDMA).

13. A mobile station for estimating velocity and Doppler frequency comprising:

means for acquiring a first plurality of time-of-arrival (TOA) measurements of a forward link signal from a first plurality of base stations at a first time;

means for acquiring a second plurality of TOA measurements of forward link signals from a second plurality of base stations at a second time;

means for acquiring a third plurality of TOA measurements of forward link signals from a third plurality of base stations at a third time;

means for determining a plurality of line-of-sight (LOS) distance measurements using the first, second and third pluralities of TOA measurements;

means for determining a plurality of velocity estimates and a plurality of angle of arrival (AOA) estimates, using the plurality of LOS distance measurements;

means for determining a plurality of Doppler frequency estimates using the plurality of velocity estimates and the plurality of AOA estimates; and

means for determining an average Doppler frequency estimate and an average velocity over a plurality of sectors based on corresponding weighting factors, wherein the first, second and third pluralities of TOA measurements are acquired over the plurality of sectors

wherein the first, second and third pluralities of TOA measurements are subject to a common constraint value based on which a forward link transmit time is constantly calibrated among the first, second and third pluralities of base stations; and

wherein the first plurality of base stations does not include base stations of the second and third pluralities of base stations, the second plurality of base stations does not include base stations of the first and third pluralities of base stations and the third plurality of base stations does not include base stations of the first and second pluralities of base stations.

14. The mobile station of claim 13 wherein the first, second and third pluralities of base stations are synchronous with each other.

15. The mobile station of claim 14 wherein the first, second and third pluralities of TOA measurements are synchronous and are derived from a Global Positioning System (GPS).

16. The mobile station of claim 13 wherein the weighting factors are based on signal strengths of the forward link signals from the first, second and third pluralities of base stations.

17. The mobile station of claim 13 wherein one of the following multiple access techniques are employed in acquiring the first, second and third pluralities of TOA measurements:

Time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA) or orthogonal frequency division multiple access (OFDMA).

18. A non-transitory computer-readable storage medium having a computer program comprising instructions, which when executed by at least one processor, operates to estimate velocity and Doppler frequency, the computer program comprising:

instructions for acquiring a first plurality of time-of-arrival (TOA) measurements of forward link signals from a first plurality of base stations at a first time;

instructions for acquiring a second plurality of TOA measurements of forward link signals from a second plurality of base stations at a second time;

instructions for acquiring a third plurality of TOA measurements of forward link signals from a third plurality of base stations at a third time;

instructions for determining a plurality of line-of-sight (LOS) distance measurements using the first, second and third pluralities of TOA measurements;

instructions for determining a plurality of velocity estimates and a plurality of angle of arrival (AOA) estimates, using the plurality of LOS distance measurements;

instructions for determining a plurality of Doppler frequency estimates using the plurality of velocity estimates and the plurality of AOA estimates; and

instructions for determining an average Doppler frequency estimate and an average velocity over a plurality of sectors based on corresponding weighting factors, wherein the first, second and third pluralities of TOA measurements are acquired over the plurality of sectors;

wherein the first, second and third pluralities of TOA measurements are subject to a common constraint value based on which a forward link transmit time is constantly calibrated among the first, second and third pluralities of base stations; and

wherein the first plurality of base stations does not include base stations of the second and third pluralities of base stations, the second plurality of base stations does not include base stations of the first and third pluralities of base stations and the third plurality of base stations does not include base stations of the first and second pluralities of base stations.