Adaptive target altitude estimation using multipath for 2D radar on spherical earth

This paper presents an adaptive target altitude estimation approach based on multipath detections from a 2D airborne radar. An adaptive multiple model iterated least squares (AMM-ILS) estimator is developed to cope with two challengers of this estimation problem: 1) unknown measurement noise variance for the reflected path; 2) inexistence of an analytical measurement function that relates the target parameters (to be estimated) and the radar measurements. A new method is presented for the numerical evaluation of the Jacobian of the measurement function. Simulation results are presented to demonstrate the estimator´s performance under various conditions. The results show that the AMM-ILS estimator yields efficient estimates which are close to their Cramer Rao lower bounds (CRLB).