Sequential Coordinates Conversion and Decoupled Linear Tracking for Airborne AESA Radars

Abstract

This paper deals with the problem of tracking a maneuvering target using an airborne electronically scanned array radar. Conventional target-tracking filters produce biased target state estimates because the angular motion of a radar platform complicates the cross-correlations between the converted measurements (CMs). As a practical alternative to this issue, the target tracking filter is designed in the predicted line-of-sight Cartesian coordinate system (PLCCS). Provided that the a priori state estimation error is small enough, the statistics of the CMs in PLCCS can be approximated accurately despite using the first and second moments of the radar measurement noises only. The resulting debiasing term leads to a satisfactory target tracking performance of the proposed filter. Furthermore, by exploiting the diagonality of the noise covariance matrix derived in the PLCCS, the proposed tracking filter is decoupled into each axis to induce a suitable real-time implementation. Through simulations, the enhanced performance of the suggested method is demonstrated.