Abstract:

It is difficult to estimate pseudo-noise (PN) sequence in nonperiodic direct sequence spread spectrum (DSSS) signals because of the nonsynchronization and irrepeatability in different durations of PN sequence  of nonperiodic DSSS signals in a noncooperative context. An efficient method that can estimate the PN sequence of DSSS signals is presented under the conditions that duration and rate of PN sequence, rate of information sequence is known and information sequence is irrelevant. With the help of sliding window, the blind estimating is achieved based on projection approximation subspace tracking (PAST) algorithms, and the PN sequence can be estimated after sorting and splicing. The experimental results show that this algorithm can estimate PN sequence quickly and accurately at low signal-to-noise ratio (SNR), largely reducing computational complexity and storage.