目标定位的分布式MIMO雷达资源分配算法

为了提高分布式多输入多输出(multiple input multiple output,MIMO)雷达的目标定位精度,分析了阵元、发射功率和信号带宽对定位精度的影响,进而提出一种将三者联合优化的资源分配算法。首先,以最小化目标的平方位置误差下限(squared position error bound,SPEB)为目标函数,建立了包含阵元、功率和带宽3个变量的优化模型;然后,通过推导最优功率分配矢量和带宽分配矢量的关系简化模型;最后利用凸松弛和循环最小化算法将优化问题转化成二阶锥形式,求解得到最优的资源分配策略。仿真结果表明,利用所提出的算法进行资源分配能明显提高目标的定位精度;信号有效带宽对目标定位精度的影响大于发射功率。

Resource allocation approach for target localization in distributed MIMO radar sensor networks

In order to improve the target location estimation accuracy in distributed multiple input multiple output (MIMO) radar, the influence of transmitted antennas, power and signal bandwidth on the estimation accuracy is analysed, and a joint resource allocation scheme is proposed. Firstly, a criterion minimizing the squared position error bound (SPEB) on the mean square error in target location estimation is derived, and the corresponding optimized model with transmitted antennas, power and signal bandwidth is built and simplified by deriving the relationship between the optimal power allocation vector and the bandwidth allocation vector. Then, the optimization problem is solved by convex relaxation and cyclic minimization algorithm (CMA). Finally, simulation results demonstrate that the localization accuracy is improved by the proposed algorithm. The results also reveal that the bandwidth has a greater impact on the localization accuracy than the transmitted power.