A MIMO moving target detection radar with optimal transmit and receive weightage

Abstract

Target detection using multiple-input multiple-output (MIMO) radar has recently gained popularity in radar research due to its ability to mitigate the target radar cross-section fading and substantial spatial diversity gain. Recently, an optimal MIMO radar detector, including optimal transmit and receive weightage, has been proposed for the detection of steady targets. A moving target differs the scenario from a steady target case due to its Doppler. Hence, the optimal detector of a steady target case does not work for the case of a moving target. Therefore, in this paper, we proposed a MIMO radar detector for the context of moving targets, including optimal transmit and receive weight schemes. For obtaining the proposed detector, knowledge about the target fading that can be applied to a moving target scenario is a prerequisite. Therefore, we proposed to use a training mechanism in which a few transmit pulses are introduced once in every coherent processing interval, and the corresponding target returns are used to estimate the target fading. However, in a moving target scenario, the target returns are Doppler-steered versions of the target fading. Therefore, it is proposed to compensate the Doppler for target fading estimation by matching a steering vector to the target returns. This type of use of online estimation of the target fading characteristics and applying it for moving target detection is the first of its kind in radar research. The proposed radar is shown to outperform the state-of-the-art MIMO radars addressed in the literature.