Multiobservation-Based Closely Spaced Extended Target Angle Estimation Method

Highly accurate target angle estimation is essential for target tracking. In closely spaced scenarios, when multiple targets are close to each other, their measurement points will be located in the same range-azimuth cell. In particular, under wideband radar conditions, the target is expanded into multiple scattering points. When multiple extended targets are located close to each other in space, there may be multiple target scattering points falling within the same range-azimuth cell. In this case, there is a large bias in the estimated angle of each extended target, which affects the accuracy of the estimated angle of the closely spaced extended target. To solve this problem, this article proposes a closely spaced extended target angle estimation method under multiple observations. The proposed method utilizes the principle of invariance of extended target scattering characteristics between adjacent pulses to predict the scattering of extended target echoes and employs maximum likelihood estimation (MLE) to estimate the extended target angle. The effectiveness and feasibility of the proposed method are evaluated through experimental simulation.