A signal processing method is provided. First, at least one transmitted signal is output to at least one target, and the target reflects at least one reflected signal to receiving antennas, which then generate receiving signals upon receipt of the reflected signal. Next, the transmitted signal and each receiving signal are processed to generate processing signals. The processing signals are arranged in a form of matrix, to generate a channel coefficient matrix having M×N channel coefficient matrix blocks. Next, the channel coefficient matrix is divided into Ndivide×Mdivide secondary channel coefficient matrices, which are then substituted into a snapshot vector matrix equation to generate a snapshot vector matrix for calculating an angle of the target. The signal processing method can establish an optimal secondary channel coefficient matrix arrangement by using a special signal preprocessing manner, to improve the resolution and accuracy of the estimated angle parameter of the target.