多发多收机制下水下小目标仿生定向探测方法及机理研究

According to the problem of distance which is too near and target recognition that is too difficult for underwater small target detection, The advantage between dolphin bio-sonar with perfect target recognition and environment adaptation and artificial sonar with desired detection distance will be integrated together, and the new theory and method of fixed and bionic adaptive collaborative detection is proposed, and the key technologies of bionic detection under the multi-transmitting and multi-receiving mechanism (MTMR) is breakout, which will provide theory and technology basis for developing new far distance high resolution target detection sonar. Focus research following: To establish bionic meaning sonar signal generation model and conformal receiving array model to provide the signal processing basis for bionic adaptive detection; The bionic detection signal modeling method based on auditory filter grouping and space-frequency coding orthogonal modulation is proposed, to solve bionic detection signal orthogonal modeling and multi-source target echo common frequency interference problem under MTMR mechanism; To overcome signal filter difficult problem of multi-source strong interference distribution dynamic change due to node real-time mobile, The method of interference suppression based spatial sparse reconstruction in case of steering vector errors; Based on the thought of using node movement to make launching beam and receiving axis-beam to point to target at same time to reduce reverb and multi-path interference, the bionic directional detection concept is set, based on these, to research joint adaptive detection method under the T-Tn/Rn MTMR mechanism with fixed bistatic sonar and moveable transceiver collection bionic sonar. The research has important scientific and practical significance on underwater security and defense.

针对水下小目标探测距离近和目标识别难的问题，通过综合生物声纳目标识别与环境自适应的优点和人工声纳探测距离上的优势，提出固定和仿生自适应协同的探测新理论和方法，突破多发多收机制下仿生定向探测的关键技术，为发展新型远距离高分辨率小目标探测声纳提供理论和技术支撑。重点研究内容如下：对海豚生物声呐探测机理进行研究，建立仿生意义的信号产生模型和共形接收基阵模型，为自适应探测奠定信号处理基础；提出基于听觉滤波器分组和空频编码正交调制的仿生探测信号建模方法，解决多发多收机制的探测信号正交建模和多源目标回波同频干扰问题；提出基于空域稀疏重构导向失配的干扰抑制方法，克服节点实时移动导致多源强干扰分布动态改变的信号滤除难题；基于节点移动使发射波束与接收轴向波束同时指向目标的思想，提出仿生定向探测的概念，以此为基础研究T-Tn/Rn多发多收机制的固定声纳和可移动仿生声纳协同的自适应探测方法。

由于水下环境的复杂性，传统声呐技术对于探测类似蛙人、UUV、鱼水雷等小目标非常困难，一方面目标强度较低，另一方面受混响干扰虚警较高，声呐系统难以适应环境的变化，导致对小目标的探测性能一直难以得到有效提高。为了解决这个问题，本项目借鉴海豚种群协同围猎和自适应探测模式，综合生物声纳和人造声纳的优势，提出多发多收机制的固定和仿生自适应协同探测方案，在国内外对海豚等齿鲸动物生物声纳生理和物理机理研究基础上，建立信号处理意义的发声和接收模型。项目基于仿生的机理，提出了仿生定向探测的概念，建立了仿生共形基阵模型，利用有限元手段分析了不同材料、厚度小目标的回波特性，实现了水下悬浮目标和掩埋目标探测技术研究，开展了小目标多基地协同探测仿真试验和湖试试验。本项目的研究成果对研制新型水下小目标预警声呐、水下科考、海难营救、水下运载器导航、近海重点水域防御和大型的涉水赛事的水下安保等具有重要意义。