Motion compensation method based on reference-element for TDM MIMO FMCW radar

Aiming at the velocity-angle coupling problem of time division multiplexing (TDM) multiple-input multiple-output (MIMO) frequency modulated continuous wave (FMCW) radar, a motion compensation method based on reference-element is proposed to realize the accurate direction estimation of moving targets. The first virtual element equivalent to the combined element T₁/R₁ of MIMO array is selected as the reference array element. The motion-induced phase is extracted by processing the signals of the reference element, then the compensation factor is constructed to complete the motion compensation of the virtual array. The simulation results and experimental results verify the effectiveness of the proposed method. The method uses fixed switching scheme based on reference element. It is not necessary to adjust the switching scheme according to the specific scene. Moreover, the method does not need to estimate the velocity, even if when the target speed is ambiguous, the method can still accurately estimate the direction of the target.