Patent ID: 6784830
Filing Date: 2004-08-31
Classification: G01S

Abstract:
A method of estimating phase and magnitude of an L2 GPS signal, the L2 signal having a P code, and a W code modulated onto it, the W code being an unknown code, the method comprising the steps of:a. generating an L1 baseband signal using the L1 signal; b. generating an L2 baseband signal using the L2 signal; c. accumulating the L1 baseband signal over one P code bit to generate an L1 second baseband signal; d. accumulating the L2 baseband signal over one P code bit to generate an L2second baseband signal; e. generating the L2 W code estimate using the L1 second baseband signal and the L2 second baseband signal, the W code estimate at a time instant being uncorrelated with the error in the inphase and the quadrature components of the L2 signal at that time instant; f. removing the L2 W code estimate from the L2 second baseband signal to generate an L2 first signal; and g. accumulating the L2 first signal to generate an L2 accumulated signal, the L2accumulated signal being a measure of the phase and the magnitude of the L2 Y code carrier signal.