Long-term integration algorithm for weak DSSS signal in large dynamic Doppler frequency scenarios

There exist integration loss and computational cost drastic increasing in long-term integration of weak DSSS (Direct Sequence Spread Spectrum) signal in large dynamic Doppler frequency scenarios. A motion compensation-double block zero padding algorithm is proposed to this problem, which uses frequency spectrum cyclic shift for Doppler frequency searching, envelope shifting and Keystone transform for code Doppler frequency compensation based on the double block zero padding algorithm. Theoretical analysis and simulation results show that, the proposed algorithm can eliminate the influence of large dynamic Doppler frequency effectively, and has high computational efficiency, the computational cost is 16% of the similar algorithm in 20 ms coherent integration, and the longer the time, the higher the efficiency.