大型声呐基阵的全方位强干扰抵消系统

An all-directional interference cancelling system for large sonar array

强干扰是制约中远程声呐性能的主要因素。对于大型声呐来说,由于过长的延时量以及过高的运算速率,抗强干扰问题始终未能解决,本文提出一种适用于大型基阵的全方位抗强干扰系统。它是自适应噪声抵消系统与一个可编程迪卡诺(DICANNE)系统的结合,在干扰与信号入射角之间的夹角比较小时,采用低采样速率的自适应噪声抵消系统;在此角度较大时,采用高采样率的DICANNE系统,从而使整个系统具有全方位抗干扰的性能。本方案在采用高性能的DSP器件时,易于实现。文中给出设计框图与硬件实施方法。

The exsistence of strong mterfernces is the main constraint factor, which influences the performance of a mid-or long-range sonar. For a sonar with large array, the problem of anti-interferences in all-direction has not been solved yet due to the requirements of over-long time dieay line and the over-high input-output rate. A method is proposed in this paper, which can be used in the sonar design with large array for supressing t e strong interferences in all direction. This is a combined architecture of adaptive noise canceller and a programmable DICANNE system proposed by V. C. Anderson. In the case that the incidental angle between signal and intefrence is small, the adaptive noise canceller will be adopted in a relative low sampling frequency. In the case that the incidental angle between signal and interference is large, the programmable DICANNE will work in the high sampling frequency so that the overall system has the ability of canceling strong interferences from all directions. The structure described in this paper is easy to implement in hardware by using the DSP chips. The block diagram of the combined system and the design idea are presented.