新型测地声呐——GPY高分辨地层剖面仪

本文介绍了一种能工作于特浅水域的高分辨地层剖面仪。首先分析了国际现有产品存在的技术问题,然后阐述GPY中所采用的声学和信号处理上的新技术,最后介绍它的主要技术特点及应用效果。     

TIME-VARYING FILTERING FOR ELIMINATING MULTIPLE ECHOES IN PROFILING SONAR

A new method,time-vrying filtering(TVF)for eliminating multiple echoes in the profilingsonar is suggested.It operates in real time and is easy to implement.In a conventional profilingsonar operation for acquiring sub-bottom structural imformation,data are often masked by mul-tiple reflection between the surface and the water-bottom interface,making the chart very difficultto interpret.The analysis shows that the multiple echoes can be greatly attenuated or even eliminat-ed,when the filter is designed according to the maximum S/N criterion.A system using this tech-nique has been develped and the experimental results obtained on the sea are quite satisfactory.     

剖面声呐中多次反射的时变过滤

本文提出并发展了一种新的适用于地层剖面声呐的信号处理技术——时变滤波.它简单易行,并且是实时的.分析表明:它能大大削弱甚至完全消除这种声呐技术中最令人讨厌的多次反射干扰,而同时保持输出信噪比接近理论上的最大值.海上实验得到了令人满意的结果.