Patent ID: 7224721

Claim:
A signal processing architecture (SPA) for acquiring a received direct sequence spread spectrum (DSSS) signal, comprising: means for sampling the received DSSS signal at a predetermined sampling rate; means for cross-correlating, in a parallel fashion, time and frequency shifted versions of the sampled DSSS signal with samples of a locally generated replica of a pseudo random noise (PN) code sequence used to spread the spectrum of the received DSSS signal in order to obtain cross-correlation values; a Doppler compensator coupled to the cross-correlating means for processing the obtained cross-correlation values in order to compensate for misalignment effects resulting from time-companding of the received DSSS signal; an integrator for non-coherently integrating groups of the compensated cross-correlation values representing corresponding time and frequency offsets of different time segments of the received signal and replica code sequence in order to obtain correlation metrics; and a detector for detecting whether a sum of the magnitudes of the correlation metrics exceeds a detection threshold, wherein the cross-correlating means further comprises: a bank of code matched filters for computing short-time correlations (STCs) entirely in parallel; and means for calculating the cross-correlation values utilizing discrete-time Fourier analysis of the computed STCs.