Location services system that reduces auto-correlation or cross-correlation in weak signals
First Claim
Patent Images
1. A location services system, comprising:
- a first data path for correlating an incoming GPS signal with a locally generated signal;
a second data path for verifying the incoming GPS signal against a lock signal, the second data path determining whether the incoming GPS signal has at least one characteristic that differentiates the incoming GPS signal from a correlated signal, wherein the correlated signal is selected from a group consisting of an auto-correlated signal and a cross-correlated signal;
a data path executive for monitoring the first data path and, when the incoming GPS signal does not contain the at least one characteristic, for continuing to search for a second incoming GPS signal; and
means for informing a user of the position of the location service system.
2 Assignments
0 Petitions
Accused Products
Abstract
The present invention discloses methods, apparatuses, and systems for eliminating auto- and cross-correlation in weak signal CDMA systems, such as GPS systems. The invention uses parallel dam paths that allow standard correlation of signals in parallel with verification of the lock signal to determine whether the system has locked onto the proper signal within the scanned signal window. The invention can be made with multiple CPUs, a single CPU with dual input modes, on multiple IC chips, or as a single IC chip solution for small, low cost reception, downconversion, correlation, and verification systems.
-
Citations
20 Claims
-
1. A location services system, comprising:
-
a first data path for correlating an incoming GPS signal with a locally generated signal; a second data path for verifying the incoming GPS signal against a lock signal, the second data path determining whether the incoming GPS signal has at least one characteristic that differentiates the incoming GPS signal from a correlated signal, wherein the correlated signal is selected from a group consisting of an auto-correlated signal and a cross-correlated signal; a data path executive for monitoring the first data path and, when the incoming GPS signal does not contain the at least one characteristic, for continuing to search for a second incoming GPS signal; and means for informing a user of the position of the location service system. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A correlator engine, comprising:
-
a first data path for correlating an incoming GPS signal in the correlator engine with a locally generated signal; a second data path for verifying the incoming GPS signal against a lock signal, the second data path determining whether the incoming GPS signal has at least one characteristic that differentiates the incoming GPS signal from a correlated signal, wherein the correlated signal is selected from a group consisting of an auto-correlated signal and a cross-correlated signal; and a data path executive for monitoring the first data path and for continuing to search for a second incoming GPS signal when the incoming GPS signal does not contain the at least one characteristic. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20)
-
Specification