A calibration method for a high-resolution hybrid MIMO turntable radar imaging system is presented. A line of small metal spheres is employed as a test pattern in the calibration process to measure the position shift caused by undesired antenna effects. The unwanted effects in the antenna near-field responses are analysed, modelled and significantly mitigated based on the symmetry and differences in the responses of the MIMO configuration.
Keywords: MIMO radar; UWB radar; inverse scattering problem; near-field antenna effect; radar calibration; radar resolution; radar system; scattering imaging; turntable radar.