Approach to adaptive cancellation of strong interference pulse in sonar
LIU Hui-tao1, WANG Li-ming1, LI Jian-long2
1.Hangzhou Research Institute of Applied Acoustics, Hangzhou 310012, China;
2. Institute of Information and Communication Engineering, Zhejiang University, Hangzhou 310027, China
For sonar detection and tracking in the presence of strong interference pulses, an adaptive interference cancellation method in the element domain was proposed, which is based on least mean square (LMS) adaptive filtering. The work reduces the computation burden by frequency domain batch processing, and achieves fast suppression of strong pulse via varied step adaptive iteration. An adaptive interference cancellation method for reference signal extraction was presented, and constrained gradient computation in the adaptive algorithm was implemented. Therefore, stable target tracking in strong interference environments can be accomplished. Experiments during sea trial indicated that strong interference pulses can be suppressed effectively using this method without any loss of target information. Stable target tracking in such environments are accomplished while the signal corrupted by strong interference pulses is detected.
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