双基地米波MIMO 雷达低空目标俯仰维DOD和DOA联合估计方法

对于双基地米波多输入多输出(MIMO)雷达低空目标俯仰维测向场景,受多径效应影响,发射接收导向矢量因存在耦合现象而与噪声子空间失去正交性,导致以多重信号分类(MUSIC)为主的子空间类算法在该场景下不可用,而基于空间平滑预处理的子空间类算法由于阵列孔径损失存在角度估计精度不高的问题。为解决上述难题,建立了双基地米波MIMO 雷达单目标和非相干多目标镜面反射信号模型,在信号模型数学变换和分析的基础上发现了一种仍旧与噪声子空间正交的导向矢量矩阵,然后利用新的导向矢量矩阵结合广义MUSIC和最大似然算法提出了双基地米波MIMO 雷达低空目标俯仰维波离方向和波达方向联合估计方法,最后通过仿真验证了所提方法的有效性和俯仰维测向性能的优越性。

A Joint Estimation Method for DOD and DOA of Low Altitude Targets Based on Bistatic Meter Wave MIMO Radar

For the low altitude target elevation direction finding scenario of bistatic multiple input multiple output (MIMO) radar, due to multipath effects, the transmitting and receiving steering vectors lose orthogonality with the noise subspace due to coupling, resulting in the unavailability of subspace class algorithms mainly based on multiple signal classification (MUSIC) in this scenario, However, subspace algorithms based on spatial smoothing preprocessing suffer from low accuracy in angle estimation due to array aperture loss. To solve the above problems, this paper establishes a bistatic meter wave MIMO radar single target and incoherent multi target mirror reflection signal model. Based on the mathematical transformation and analysis of the signal model, a steering vector matrix that is still orthogonal to the noise subspace is discovered, then, a new guidance vector matrix combined with generalized MUSIC and maximum likelihood algorithm was used to propose a joint estimation method for the elevation direction of departure and arrival of low altitude targets in a bistatic meter wave MIMO radar. Finally, simulation experiments verified the effectiveness of the proposed method and the superiority of the elevation direction finding performance.