Patent ID: 6084927
Filing Date: 2000-07-04
Classification: G01S,H04B

Abstract:
A method for use in decoding a composite signal having a signal-distorting component, the method comprising the steps of:receiving a digital composite signal that can vary with time t and that has a digital signal bit period with a selected length .DELTA..tau..sub.chip ;generating a selected digital reference signal;generating a first weighting signal that is not constant in time and that, when mixed with the reference signal and the composite signal, reduces the effect of presence of a signal-distorting component in the composite signal;mixing the first weighting signal with the reference signal and the composite signal to produce a first correlation function that represents a first timing relationship between the composite signal and the reference signal;generating a second weighting signal that is not constant in time and that, when mixed with the reference signal and the composite signal, reduces the effect of presence of a signal-distorting component in the composite signal;mixing the second weighting signal with the reference signal and the composite signal to produce a second correlation function that is distinct from said first correlation function and that represents a second timing relationship between said composite signal and said reference signal; andforming a correlation difference function .DELTA.AC(.tau.) that is a difference between the first correlation function and the second correlation function, where .tau. is a time shift variable that allows variation of at least one of the first timing relationship and the second timing relationship.