This paper considers a novel approach to joint estimation of the velocity (or Doppler frequency) and Direction of Arrival (DOA) of targets by time division multiplexing (TDM) multiple-input multiple-output (MIMO) radars in automotive applications. The TDM MIMO radars create orthogonal probing signals (in time domain) by allocating a transmitter to a separate time slot. In this paper, we consider a standard TDM MIMO radar to be the one where transmitters are activated sequentially according to their natural spatial order. The drawback of the standard TDM MIMO approach is the coupling of velocity and DOA information of the targets. The coupling reduces the unambiguous estimation interval of the Doppler frequencies of the targets by the number of transmit antennas being multiplexed. In this paper, we propose a novel cost function to jointly estimate both the Doppler frequency and the DOA of each target by reinstating the reduced unambiguous Doppler spectrum interval. Our approach is generally applicable to solve the Doppler ambiguity problems associated with any colocated standard TDM MIMO radar. To confirm this, we present the simulation results that evaluate the performances of two widely deployed TDM MIMO radar antenna configurations: non-overlapped and overlapped arrays. Moreover, we derive the analytical expressions to study the statistical performance of the proposed method. The simulation examples are presented to verify the performance of the proposed method as well as the accuracy of the analytical expressions.

中文翻译：

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TDM MIMO 汽车雷达的联合多普勒频率和到达方向估计


本文考虑了一种通过汽车应用中的时分复用 (TDM) 多输入多输出 (MIMO) 雷达联合估计目标速度（或多普勒频率）和到达方向 (DOA) 的新方法。 TDM MIMO 雷达通过将发射机分配到单独的时隙来创建正交探测信号（在时域中）。在本文中，我们认为标准 TDM MIMO 雷达是发射机根据其自然空间顺序顺序激活的雷达。标准 TDM MIMO 方法的缺点是目标速度和 DOA 信息的耦合。该耦合通过复用的发射天线的数量来减少目标的多普勒频率的明确估计间隔。在本文中，我们提出了一种新颖的成本函数，通过恢复减少的明确多普勒频谱间隔来联合估计每个目标的多普勒频率和 DOA。我们的方法通常适用于解决与任何共置标准 TDM MIMO 雷达相关的多普勒模糊度问题。为了证实这一点，我们提供了评估两种广泛部署的 TDM MIMO 雷达天线配置（非重叠阵列和重叠阵列）性能的仿真结果。此外，我们推导了解析表达式来研究所提出方法的统计性能。仿真例子验证了该方法的性能以及解析表达式的准确性。