A Modified Large Dynamic Weak DSSS Signal Acquisition Algorithm Based on DBZP

Abstract

In order to solve the problem of fast acquisition of weak direct sequence spread spectrum (DSSS) signals under the condition of large dynamic, this paper proposes a modified DSSS signal acquisition algorithm based on the double block zero padding algorithm. The proposed algorithm realizes segmented Doppler search by frequency compensation of the baseband signal, then the code Doppler of partial correlation result is corrected by pre-compensating local pseudo-code and the Keystone transform. In addition, the computational cost of the algorithm is reduced by introducing the sparse fourier transform. Theoretical analysis and simulation results show that the proposed algorithm can effectively eliminate the influence of large dynamic on long-term accumulation of the weak DSSS signals. Compared with the representative algorithm, the proposed algorithm, which reduces the computational cost by 48.9% when the coherent accumulation time is 5ms, has higher computational efficiency.