依赖信号噪声场景下MIMO雷达稳健波形设计

Study on MIMO Radar Robust Waveform Design in the Case of Signal-Dependent Noise

考虑依赖信号噪声场景下MIMO雷达的稳健波形优化问题。根据最小最大方法,基于克拉美-罗界描述了改善MIMO雷达最差情况参数估计性能的稳健波形优化问题。为求解所得NP问题,提出一种新的基于对角加载(DL)的迭代方法。此方法利用哈达玛不等式将内层优化分解为若干子问题,以降低运算复杂度从而利于工程应用,基于DL方法将子问题转化为凸问题,外层优化也可转化为凸问题,因而可获得高效求解从而便于硬件实现。初始问题最优解可通过对迭代算法得到的解进行最小二乘拟合得到。数值仿真验证了所提方法的有效性。

The work presented here addresses the problem of robust waveform design for multipleinput multiple-output(MIMO) radar in the case of signal-dependent noise. Following the min-max approach,the robust waveform design is formulated based on Cramér-Rao Bound(CRB),which aims to improve the worst-case estimation accuracy of MIMO radar. In order to tackle the resultant NP-hard problem,a new diagonal loading(DL) based iterative method is developed,in which the inner optimization problem can firstly be decomposed to some independent sub-problems by using the Hadamard’s inequality to reduce the computational complexity for benefitting the application in practice,and then these sub-problems can be reformulated into convex issues by using DL method,as well as the outer optimization problem can also be relaxed to a convex issue, and hence this optimization problem can be solved very effectively so that the implementation on hardware can be simplified. Following that,an optimal solution to the original issue can be obtained via the least squares(LS)fitting of the solution acquired by the iterative approach. Numerical simulations show the efficiency of the proposed method.