I. Introduction
Active target localization has been the focus of considerable research efforts due to its usefulness in various applications. Particularly in [1]–[3], multiple-input-multiple-output (MIMO) radar systems with widely distributed antennas take advantage of the geographical spread of the deployed sensors and support target localization through either direct or indirect multilateration [4]. Therein, the impact of radar antenna position uncertainties (APUs) on the performance of localization algorithms was not taken into account, while the antenna geometry was mainly considered [5], [6]. However, in practice, the exact positions of antennas are not available quite often even after calibration and hence the localization performance may deteriorate significantly in the presence of antenna positions imperfections.