Doppler spreading depression method in underwater communication

The invention provides a Doppler spreading depression method in underwater communication. Since the prior art has many defects, the method comprises the following steps: firstly constructing a broadband underwater acoustic signal orthogonal angular domain projection-based vector, and then performing the fast Fourier transform on a receiving signal to obtain different frequency point signals, performing the orthogonal projection on the frequency point signals to obtain receiving signals of different sub-spaces on the time domain; estimating the sub-space resampling Doppler factor; firstly performing coarse compensation on the sub-space signal, and then performing the resampling on the receiving signals of different sub-spaces, performing the residual Doppler compensation on the resampled sub-space signal, performing the sub-space channel estimation on the compensated sub-space signal to construct a channel matrix, and performing the symbol demodulation based on minimum linear mean square error method. By using the method provided by the invention, the main Doppler influence is removed, the estimation value of the residual Doppler is reduced, so that the system performance is greatly improved.