Abstract:Based on cyclic spectrum theory, property of spectral correlation for DSSS signal and stationary noise is analyzed. Based on characteristics, DSSS signal can be detected, and the carrier frequency and chip rate can be estimated in distribution of cyclic frequency domain and spectral frequency domain based on cyclic spectrum envelope. In the condition of limited time, this paper proposed time-limited segment-average frequency-smoothed cyclic periodogram algorithm in order to avoid multidimensional searching, and discuss the algorithm against noise and statistical properties. Theory suggests that it suppress the noise level further. By computer simulation, the algorithm achieved estimation under low SNR, and certificated data length and smooth points influence on experimental results, and proved the correctness of theoretical analysis.