基于压缩感知的蒸发波导时空态势获取方法研究

Evaporation duct is a double-edged sword, so its time-space situation urgently needs to be sensed efficiently and accurately for profit and avoiding loss. But, it not only is high cost-effective but also can't meet the progressively requirements by just increasing the density of buoys. Compressed sensing provides the theoretical basis for the time-space situation awareness of evaporation duct for a long time and in a large area, which is recovered from a small amount of low speed measurements. There are still some problems like 3-D high efficient measuring and exact reconstruction of blind sparsity and noisy signal. The research centers on those problems mainly includes (1) proposing a 3-D equivalent measuring method for situation awareness of evaporation duct in time-space correlation condition, and providing a new way of enhancing the sampling efficiency; (2) discussing the sparsity estimation criterion and its constraint condition and covering the shortage that the traditional norm is not able to scale the situation sparsity, and appearing to solve the problem that the recovery algorithms require deterministic sparsity; (3) presenting de-noising reconstruction algorithm for time-space situation of evaporation duct to improve on the decreased performance in recovery caused by noise. The traditional mode of "high speed sampling first and mass discarding then" is abandoned, and it's hopeful that the time-space situation of evaporation duct is sensed efficiently and precisely. Meanwhile, the compressed sensing theory about 3-D approximately sparse noisy signal is enriched.

海上蒸发波导是一把"双刃剑"，急需高效、准确地获取其时空态势以趋利避害，而仅靠增大浮标布设密度来提高态势感知时空分辨率的方式，不但费效比过高，且无法满足日益增长的需求。压缩感知理论为从少量低速的观测数据中获知长时间、大范围蒸发波导态势提供了理论基础。本项目围绕其中存在的三维高效观测、盲稀疏度条件下和含噪环境下精确重构等三大问题展开研究。主要内容包括：⑴提出时空相关条件下蒸发波导态势的三维等效观测方法，为充分利用时空相关性提高采样资源的使用效率提供一种新的途径；⑵研究蒸发波导态势的稀疏度约束及估计方法，弥补常规范数难以衡量波导态势稀疏度的不足，有望解决重构算法要求稀疏度确知的难题；⑶提出蒸发波导态势的去噪重构方法，解决噪声削弱信号稀疏度后造成的重构性能下降的问题。 本项目摒弃传统的"先高速采样，后大量丢弃"的模式，有望实现蒸发波导态势的高效、准确感知，有助于丰富三维含噪近似稀疏信号的压缩感知

随着我国海洋战略的深入部署，我军随之启动由“近海防御”向“近海防御与远海护卫”结合的新一轮战略转型。在各方对海上制电磁权激烈争夺的背景下，蒸发波导对电子系统（如雷达、通信等）的影响越来越不容小觑，俨然已成为一把“双刃剑”：既有助于实现超视距通信、探测，又可能逆向致使自身过早暴露。因此，获知蒸发波导态势刻不容缓。面对充满未知的广袤海洋，如果仅仅依靠增大探测器布设密度的方式获取波导信息，不仅费效比过高，而且将始终无法满足对态势感知时间、范围和精度日益增长的需求。因此，获知海上蒸发波导态势已成为关乎国民经济发展以及夺取未来海战场优势地位的关键问题，同时也是一个航行安全、海上通信、雷达探测及电子对抗等领域亟待解决的世界性重大难题。.压缩感知理论为从少量低速的观测数据中获知长时间、大范围蒸发波导态势提供了理论基础。本项目围绕其中存在的三维高效观测、盲稀疏度条件下和含噪环境下精确重构等三大问题展开研究。主要内容包括：⑴提出时空相关条件下蒸发波导态势的三维等效观测方法，为充分利用时空相关性提高采样资源的使用效率提供一种新的途径；⑵研究蒸发波导态势的稀疏度约束及估计方法，弥补常规范数难以衡量波导态势稀疏度的不足，有望解决重构算法要求稀疏度确知的难题；⑶提出蒸发波导态势的去噪重构方法，解决噪声削弱信号稀疏度后造成的重构性能下降的问题。.本项目摒弃“先高速采样，后大量丢弃”的传统模式，有助于未来海战场上蒸发波导信息的准确高效感知及重构，观通、航保、通信等部门人员可通过本项目成果及时了解蒸发波导的空间分布、时间变化等规律，特别适合于海上舰艇编队的应用情况。同时，我国东部沿海及南海海域的海面波导资源十分丰富，利用其进行超视距通信，可在特定条件下作为常规微波通信的补充，延长通信距离，具有重要的军事应用价值。