Receiver for performing position location with efficient rotator

• US 6,324,227 B1
• Filed: 09/09/1998
• Issued: 11/27/2001
• Est. Priority Date: 09/09/1998
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Kang, Inyup, Sih, Gilbert C., Zou, Qiuzhen
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): Jiang, Lenny
• Application Number:
  US09/150,074
• Time in Patent Office: 1,175 Days
• Field of Search: 375/134, 375/147, 375/149, 375/150, 375/316, 375/340, 375/343, 342/357.09, 342/357.12, 342/357.01, 342/357.05, 342/357.06, 701/200, 701/201, 701/213
• US Class Current: 375/343
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/254 relating to Doppler shift of satellite signals
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 19/30 code related G01S19/246 takes precedence
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station

Abstract

The present invention is a novel and improved method and apparatus for performing position location in wireless communications system. One embodiment of the invention comprises a method for performing position location comprising the steps of receiving signal samples, generating a coarse acquisition sequence, rotating the coarse acquisition sequence yielding a rotated coarse acquisition sequence, and applying the rotated coarse acquisition sequence to the signal samples at a set of time offsets yielding correlated output data.

Claims

1. A method for performing position location comprising the steps of:

(a) receiving signal samples;

(b) generating a coarse acquisition sequence;

(c) rotating said coarse acquisition sequence yielding a rotated coarse acquisition sequence;

(d) applying said rotated coarse acquisition sequence to said signal samples at a set of time offsets yielding correlated output data.

2. The method as set forth in claim 1 further comprising the step of accumulating said correlated output data.

3. The method as set forth in claim 2 wherein step (d) comprises the steps of:

performing coherent integration;

performing non-coherent integration.

6. The method as set forth in claim 3 wherein said non-coherent integration is performed on results generated from said coherent integration.

7. The method of claim 1 wherein a coarse search is performed, followed by a fine search.

8. The method as set forth in claim 1 further comprising the step of storing said rotated coarse acquisition sequence.

4. The method as set forth in 3 wherein said coherent integration is performed over a first duration, and said non-coherent integration is performed over a second duration.

5. The method as set forth in 4 wherein said first duration is approximately one ms.