In this paper, we analyze the accuracy of target localization in multiple-input multiple-output (MIMO) radars with widely-separated antennas. The relative target-antennas geometry plays an important role in target localization. We investigate the optimal placement of transmit and receive antennas for coherent and non-coherent processing, based on maximizing the determinant of the Fisher information matrix (FIM), which is equivalent to minimizing the error ellipse area. The square root of the average determinant of the FIM can be expressed as a product of three parameters, namely the equivalent single radar gain, coherency gain and geometry gain. It is shown that the coherency gain of coherent MIMO radar is greater than the non-coherent one, while the geometry gain of coherent MIMO radar is always smaller than or equal to the non-coherent case. The maximum value of the geometry gain for a MIMO radar system with $N$ transmit and $M$ receive antennas is proportional to $MN$ for coherent while it is $\sqrt{2}MN$ for the non-coherent case.

中文翻译：

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分布式MIMO雷达中的目标定位几何增益。

在本文中，我们分析了具有广泛分隔的天线的多输入多输出（MIMO）雷达中目标定位的准确性。相对目标天线的几何形状在目标定位中起着重要作用。我们基于最大化Fisher信息矩阵（FIM）的决定因素（等效于最小化误差椭圆面积），研究用于相干和非相干处理的发射天线和接收天线的最佳放置。FIM平均行列式的平方根可以表示为三个参数的乘积，即等效单雷达增益，相干增益和几何增益。结果表明，相干MIMO雷达的相干增益大于非相干MIMO雷达的相干增益，而相干MIMO雷达的几何增益始终小于或等于非相干情况。$ N $ 传输并 $ M $ 接收天线与 $ MN $ 因为它是连贯的 $ \ sqrt {2} MN $ 对于非连贯的情况。