| 摘要: |
| 混响是主动声纳检测的主要背景干扰，由于它是一种非平稳的有色噪声，使得工作在白噪声条件下的检测器性能受到极大限制。在混响背景下实现目标回波检测，常采用自回归（AR）模型对宽带回波预白化处理，但在强混响背景条件下，白化后直接进行匹配滤波检测的结果不甚理想。针对此问题，在AR模型预白化基础上，提出一种改进方法，对白化后信号先进行二分奇异值分解（SVD）处理，有效去除大部分混响干扰，然后再作匹配检测。仿真实验分析表明，相比于仅白化后的匹配滤波检测，该方法可提高信混比约3 dB，匹配检测效果得到了明显改善。 |
| 关键词: 主动声纳 线性调频信号 回波检测 强混响 预白化 匹配滤波 信混比 |
| DOI： |
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| 基金项目:国家高技术研究发展计划(863计划)项目 |
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| Echo detection of LFM signal under strong reverberation background |
| SHU Xianglan,SUN Rongguang,MA Xin |
| () |
| Abstract: |
| Reverberation is the main background interference in active sonar detection. Because the reverberation is a nonstationary colored noise,which degrades the performance of the matched filter in white noise background. For the detection of target echo in reverberation background,the broadband echo is used to be pre-whitened with the Auto-Regressive(AR) model，however，the result is not satisfying under the background of strong reverberation. In order to solve the problem,this paper proposes an improved method on the basis of the AR model for pre-whitening processing.The whitened signal can be firstly processed by Singular Value Decomposition(SVD) to eliminate a majority of reverberation interference effectively,then the remained signal is disposed with matched filter. Simulation and analysis indicate the improved method can enhance signal to reverberation ratio(SRR) about 3 dB compared with traditional one,so it obviously improves the performance of matched filter. |
| Key words: active sonar LFM signal echo detection strong reverberation pre-whitening matched filter signal to reverberation ratio |
