Satellite high dynamic large doppler frequency offset channel soft spread spectrum signal analysis method

Abstract

The application provides a soft spread spectrum signal analysis method for a satellite high dynamic large Doppler frequency offset channel, wherein the acquired signal is divided into multiple code words according to the code word length through S1; the real part and the imaginary part of the spread spectrum code sequence are cyclically shifted to obtain multiple spread spectrum sequence combinations through S2; the frequency of any first code word is searched according to each combination to obtain multiple frequency offsets, and multiple correlation values corresponding to each combination are obtained, and the maximum value corresponding to each combination is determined as the correlation value of the corresponding combination; the correlation values of each spread spectrum sequence combination are compared, and the combination corresponding to the maximum value is determined as a target spread spectrum sequence combination through S4; the target spread spectrum sequence combination is decoded through S5, the first code word is mapped to a k-bit original sequence according to the decoding result, and the correlation value of the target spread spectrum sequence combination is multiplied by the original sequence to obtain a despread result; steps S2-S5 are repeated until all code words are despread through S6, and a complete signal is output according to all despread results, so that the spread spectrum gain is released under a low signal-to-noise ratio condition.

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