Novel Movement-Based Methods for the Calibration of Colocated Multiple-Input Multiple-Output Radars

Abstract

It is well-known that the availability of transmit and receive arrays in colocated multipleinput multiple-output radar systems can be exploited to detect multiple targets, and estimate their range and angular coordinates. Unluckily, the accuracy achieved in the estimation of target parameters can be severely affected by hardware nonidealities. The impact of these nonidealities can be mitigated through the adoption of specific methods explicitly developed to estimate and compensate for them, i.e., briefly, of calibration methods. As far as we know, until now, most of the calibration techniques proposed in the technical literature for colocated multiple-input multiple-output radars are based on the idea of placing one or more reference targets in front of the considered radar device at perfectly known and fixed locations, and quantifying the difference between the expected radar image and the measured one. In this manuscript, two novel calibration methods are proposed. Both exploit the measurements captured by a colocated multipleinput multiple-output radar device at multiple positions; for this reason, the acquisition of such measurements involves the movement of the radar. Moreover, one of these methods does not require any knowledge about the number, position or radar cross section of the reference targets, provided that all these are in far-field. The other one, instead, requires the use of a single reference target in near-field conditions. The proposed methods are tested on a commercial radar device and compared with a traditional method for radar calibration.