the detection performance of towed linear array underwater detection equipment will be disturbed by the radiated noise of the tug. In order to enhance the detection performance, the key is to start with the array spacing and subsequent signal processing. This paper focuses on the reception directivity of 1/4 wavelength spacing array. The simulation results show that, unlike the half-wavelength spacing array, the end directivity of the quarter-wavelength spacing array is asymmetric, which can significantly suppress the interference in the first direction of the towed array and improve the tail detection performance. And the receiver signal combined with mulling can suppress tug noise.