水下声信标信号的多脉冲匹配滤波改进方法

Improved method of multi-pulse matched filtering for underwater acoustic beacon signal

水下声信标信号检测是搜寻黑匣子的重要技术之一。针对水下声信标信号声源级低、脉冲宽度窄所带来的检测难题,充分利用声信标信号周期短、相邻脉冲信号相关性强等特点,提出了一种基于多脉冲积分的改进匹配滤波方法,通过前后脉冲匹配方法克服标准信号匹配处理中因信号畸变带来的匹配处理增益下降,通过多脉冲累积提高积分增益。通过仿真实验验证,当取多脉冲累积数为6时,在理想白噪声环境下,所提改进方法比传统单脉冲匹配滤波检测性能提高约4 dB,特别是在存在明显多普勒影响下,传统方法适应性下降,所提改进方法有9 dB的性能提高。通过对湖上实验数据的处理也验证了所提方法的有效性。

Underwater acoustic beacon signal detection is one of the important technologies to search for black boxes.Aiming at the detection difficulties caused by low sound source level and narrow pulse of underwater acoustic beacon signal,an improved matched filtering method based on multi-pulse integration is proposed by full use of the characteristics of short beacon signal period and strong correlation between adjacent pulse signals.This method overcomes the matched processing gain decrease due to signal distortion in standard signal matched processing through front and back pulse matching formula,and improves the integral gain through multi-pulse accumulation.The simulation results show that when the cumulative number of multiple pulses is 6,the detection performance of the improved method is about 4dB higher than that of the traditional single pulse matched filter in the ideal white noise environment;in the presence of obvious Doppler effect,the adaptability of the traditional method is reduced,while the performance of the improved method is improved by 9 dB.The validity of this method is also verified by processing the lake test data.