This paper considers mutual interference mitigation among automotive radars using frequency-modulated continuous wave (FMCW) signal and multiple-input multiple-output (MIMO) virtual arrays. For the first time, we derive a general interference signal model that fully accounts for not only the time-frequency incoherence, e.g., different FMCW configuration parameters and time offsets, but also the slow-time code MIMO incoherence and array configuration differences between the victim and interfering radars. Along with a standard MIMO-FMCW object signal model, we turn the interference mitigation into a spatial-domain object detection under incoherent MIMO-FMCW interference described by the explicit interference signal model, and propose a constant false alarm rate (CFAR) detector. More specifically, the proposed detector exploits the structural property of the derived interference model at both \emph{transmit} and \emph{receive} steering vector space. We also derive analytical closed-form expressions for probabilities of detection and false alarm. Performance evaluation using both synthetic-level and phased array system-level simulation confirms the effectiveness of our proposed detector over selected baseline methods.

翻译：本文研究了基于调频连续波（FMCW）信号与多输入多输出（MIMO）虚拟阵列的汽车雷达之间的互干扰抑制问题。我们首次推导了通用的干扰信号模型，该模型不仅全面考虑了时频非相干性（例如不同FMCW配置参数与时间偏移），还涵盖了慢时编码MIMO非相干性以及受害雷达与干扰雷达之间的阵列配置差异。结合标准MIMO-FMCW目标信号模型，我们将干扰抑制问题转化为在显式干扰信号模型所描述的非相干MIMO-FMCW干扰下的空间域目标检测问题，并提出了一种恒虚警率（CFAR）检测器。具体而言，所提出的检测器利用了推导出的干扰模型在发射与接收导向矢量空间中的结构特性。我们还推导了检测概率与虚警概率的解析封闭表达式。基于合成级与相控阵系统级仿真的性能评估证实了所提检测器相较于所选基线方法的有效性。