面向单基地MIMO雷达的展开增广互质阵设计:低互耦和高自由度

Unfolded Augmented Co-prime Array for MIMO Radar:Low Mutual Coupling and High Degree of Freedom

针对现有多输入多输出(multiple input multiple output, MIMO)雷达互耦率高、自由度低的问题,提出了一种低互耦率、高自由度的展开增广互质阵MIMO雷达设计方式。首先在收发两端分别部署展开增广互质阵列。然后通过引入稀疏扩展因子,使展开增广互质阵列子阵的阵元间隔得到扩展,并得到所提出的展开增广互质MIMO雷达阵元位置的闭式表达式。随后通过广义和差联合阵列的概念,详细推导出了雷达的连续自由度和总自由度的闭式解。最后通过基于空间平滑的多重信号分类方法得到波达方向(direction of arrival, DOA)估计。与其他互质MIMO雷达结构相比,所提出的展开增广互质MIMO雷达能够获得更多的连续自由度并具有更低的互耦率。仿真结果验证了所提出的雷达结构在DOA估计方面的有效性和优势。

Aiming at the problem of high mutual coupling rate and low degree of freedom(DOF)of existing multiple input multiple output(MIMO)radar,an unfolded augmented co-prime MIMO radar is proposed in this paper.First,the unfolded augmented co-prime array is deployed in both transmitter and receiver.Then,by introducing the sparse expansion factor,the inter-element spacing of different subarrays in unfolded augmented co-prime array is extended,and the closed-form expression of the position set for the unfolded augmented co-prime MIMO radar is obtained.Then,the generalized sum and different co-array(GSDC)concept is used to derive the closed-form solutions of continuous DOF and total DOF.Finally,the direction of arrival(DOA)is obtained by spatial smoothing multiple signal classification(MUSIC)method.Compared with other co-prime MIMO radar structures,the proposed MIMO radar offers higher DOF and lower mutual rate.Simulation results verify the effectiveness and advantages of the proposed radar structure in DOA estimation.