According to the multiple-antenna matrix structure of ship communications,we present a new method for the detection of non-cooperative DS signals which are suitable for the ship communications and different from traditional methods for the detection of multiple signals.The kernel independent component analysis is employed to the pretreatment of DS signals in this method to solve the problem that it is difficult to be separated for the signals when the overlapping of several signal frequency bands and the spectrum crossing occur.Thus the accuracy of detection and recognition of DS signals in the subsequent parts is improved.Simulation results show that the presented detection method is effective.