Waveform Degradation of the MIMO Virtual Array

Under scenarios with sufficient signal power, co-herent multiple-input multiple-output (MIMO) radar potentially offers enhanced detection and estimation performance compared to the traditional phased array due to the formation of a virtual array. While performance is well-documented for ideal orthogonal waveforms, these assumptions do not hold in de-ployment of realistic MIM 0 systems, where processing errors and waveform cross-correlation complex-valued cross terms are introduced. The latter is shown to introduce angle- and time-varying changes to the transmit gain, perceivable as a steering vector mismatch in virtual array beamforming. This paper highlights the effects of virtual array phase errors caused by unintended spatial interactions of non-orthogonal waveforms and provides considerations for MIMO array placement.