Shallow water waveguides are very complex in sound propagation due to the existence of seafloor boundary and inhomogeneous scatterers

which causes serious interference to signal processing. Aiming at the adverse effect of multipath on DOA estimation in complex shallow water environment

a DOA estimation algorithm based on time reversal-compressive sensing (TR-CS) is proposed in this paper. To solve the interference of shallow water multipath to channel sparsity when DOA estimation is performed by using compressive sensing (CS)

the algorithm introduced the time reversal theory (TR) to preprocess the signal

transmitted the signal to the channel again

and established the DOA estimation model of shallow water target based on TR. The algorithm uses the space-time focusing property of TR to correct the multipath distortion and analyzes the performance of the algorithm under different snapshot numbers and complexity environments. Simulation results show that under low SNR and small snapshot conditions

the introduction of TR significantly suppressed sidelobe clutter

increased the sparsity of the channel and the signal-to-noise ratio of the array received signals

and improved the performance of DOA estimation in complex shallow water environment. The performance improvement was more obvious in the environment with more severe multipath effects.