Patent ID: 7693211

Claim:
A method for tracking satellite signals at a satellite navigational receiver, wherein the receiver correlates a received satellite signal with a local signal into correlation samples, comprising: computing a Doppler frequency and a rate of change of the Doppler frequency; computing a phase for each correlation sample based on the computed Doppler frequency and the computed rate of change of the Doppler frequency; compensating for a phase shift of each sample with the computed phase for the respective sample; coherently integrating the phase compensated samples over the length of one or more data bit for an in-phase (I) component to obtain an I value; coherently integrating the phase compensated samples over the length of one or more data bit for a quadrature (Q) component to obtain a Q value; determining a sign of each data bit of the received signal based on a relative value of the I value with respect to the Q value; and determining a quality of tracking value based on the relative value of the I value with respect to the Q value.