摘要
采用压缩感知理论的穿墙稀疏成像恢复算法需要感知矩阵满足有限等距性质(RIP),最直接的验证方法是判定感知矩阵的相干系数是否较小。针对现有的穿墙多输入多输出(MIMO)阵列稀疏成像方法没有验证感知矩阵是否满足RIP性质而容易出现重构失败并导致成像模糊的问题,提出一种联合感知矩阵优化的穿墙MIMO阵列稀疏成像方法。该方法首先依据配置指标将阵元配置为两端发中间收和分时复用的模式,既能使感知矩阵的相干系数最小,又能获得均匀而不冗余的等效虚拟阵元;然后,从中选取部分能够满足感知矩阵相干系数最小的虚拟阵元组合,使用可分离逼近结构稀疏恢复算法充分考虑扩展目标信号的结构稀疏先验信息对其进行稀疏成像重构;最后,选取成像性能指标较好的一组作为成像结果。仿真和实验结果表明,该方法降低了运算量和虚拟阵元间的干扰,节约了硬件成本,提高了算法的稀疏重构性能,获得了高分辨的穿墙扩展目标成像。
The compressed sensing sparse imaging restoration algorithm about through-wall radar requires that the sensing matrix satisfies the RIP property,and the most direct verification method is to determine whether the coherence coefficient of the sensing matrix is small. The existing sparse imaging methods of MIMO through-wall array do not verify whether the sensing matrix satisfies the RIP properties and prone to cause reconstruction failure and blurred images. In this paper,a joint sensing matrix optimization sparse imaging method for through-wall MIMO array is proposed. Firstly,the array element is configured as the time division multiplexing mode that can be transmitted at both ends and received in the middle according to the configuration index requirements,which can minimize the coherence coefficient of the sensing matrix and obtain uniform and irredundant equivalent virtual array. And then a combination that have some virtual array elements which can satisfy the minimum coherence coefficient of the sensing matrix is selected. The structure sparse compressed sensing recovery algorithm based on group separable approximation is used to reconstruct sparse image,which takes full account of the sparse prior information of extended target signal. Finally,a group of better imaging performance indexes is selected as the imaging result. The simulation and experimental results show that this method reduces the computational complexity and the interference between the virtual array elements,saves the hardware cost,improves the sparse reconstruction performance of the algorithm,and achieves high resolution through-wall extended target imaging.
作者
戴耀辉
晋良念
DAI Yaohui;JIN Liangnian(Guangxi Key Lab of Wireless Wideband Communication & Singnal Processing,Guilin 541004,China;Institute of Information and Communication,Gtfilin University of Electronic Technology,Guilin 541004,China)
出处
《现代雷达》
CSCD
北大核心
2018年第12期34-40,共7页
Modern Radar
基金
国家自然科学基金资助项目(61461012)
广西无线宽带通信与信号处理重点实验室项目(GXKL06160106)
广西自然科学基金资助项目(2017GXNSFAA198050)
关键词
穿墙稀疏成像
有限等距性质
多输入多输出阵列
重构性能
through-wall sparse imaging
restricted isometry property
MIMO array
reconstruction performance
作者简介
通信作者:戴耀辉,男,1991年生,硕士研究生。研究方向为超宽带穿墙雷达稀疏成像技术。Email:1543841570@qq.com;晋良念,男,1974年生,博士,副教授。研究方向为自适应信号处理、超宽带雷达隐藏目标成像与识别。