基于空时二维压缩投影接收机的MIMO雷达

The proposal will investigate on a new architecture of MIMO radar system with receiver based on space-time two-dimensional compressive projection that is firstly proposed by the applicant. Aimed at the conflict of sampling rate and resolution in radar system, we propose a new receiver structure, named as space-time 2D compressive projection receiver, to replace the conventional matching filters. The MIMO radar with this new type receiver can be equipped with sparse aperture of sensors and can work at sub-nyquist sampling rate. The concern of the research is how to fully utilize the information provided by multiple transmitted waveforms so that we are able to decrease the sampling rate as well as target parameter estimation with high accuracy and target imaging with super-resolution via such a compressive projection and sparsity recovery process. .As solutions, we propose a kind of receiver structure with multiple channel analog modulation and filter, the parameters of which is desined by circuit element constraints and representation matrix. An approach of waveform design is presented by discrete chaos sequence. And one scheme of directly echo sampling based on the idea of transmitted waveform matrix partition is proposed. We also give the ways to obtain robust recovery algorithms based on statistical prior knowledge and the ways to design quick recovery algorithms based on structural prior information. Finally, we will do some experiments on the available MIMO system of our laboratry to evaluate and validate the research results. In summary, this proposal has a innovative and meaningful scientific problem and has a feasible roadmap and a thorough plan of the research. The possible benefit of the research is also easily predicted which will guide the future theoretical research and promote the application of compressive sampling technique in radar system if the proposal is supported by NSF.

本项目针对传统雷达存在的分辨率与采样速率间的固有矛盾，提出一种基于空时二维压缩投影接收机的MIMO雷达处理方案。这种新型的空时二维压缩投影接收机替代了传统雷达的匹配滤波，可以实现稀疏孔径和欠Nyquist速率的空时双稀疏采样。研究目标是：充分利用发射波形提供的信息，通过压缩投影和稀疏重构过程，来降低雷达系统采样速率，以实现高分辨雷达目标参数估计和成像。我们提出一种多通道模拟调制和滤波结构，根据表示模型和物理约束来确定其参数；提出基于离散混沌序列的发射波形设计方法以及一种基于发射波形矩阵分拆的直接回波欠采样方案；提出分别基于统计特性先验信息和目标结构先验信息来实现稳健和快速的重构算法。最后用实测数据验证本项目的研究成果。本项目有创新性和可行性，研究成果将对CS理论在雷达中应用具有重要的理论指导意义和应用价值。

为了突破传统雷达存在的分辨率与采样速率间的固有矛盾，本项目充分考虑雷达系统的时间、频域和空间资源，发展了能够实现稀疏孔径和欠Nyquist速率下的空时双稀疏采样新理论，设计了双稀疏采样下的空时二维压缩投影机结构，以及多种调制采样结构下的模拟电路实现方案；实现了基于4通道模拟滤波网络的1/10欠Nyquist速率下的低功耗压缩接收机硬件系统，实现了空时二维压缩投影接收机原型，搭建了国内首个空时二维压缩投影接收机综合演示验证系统，对现有正交MIMO雷达发射波形下的压缩接收机进行了性能验证；在此基础上，对多种重构算法进行了研究，分析了不同重构算法对系统参数的依赖程度，并提出了基于有限信息率理论的超宽带脉冲信号采样新方法，实现了低速率系统采样下的高分辨目标探测、成像、分类与识别等应用。研究成果在国际知名期刊会议上发表论文25篇，授权国家发明专利8项，申请国家发明专利2项。