Three-dimensional target motion analysis using azimuth/elevation angles

We present new closed-form and low-complexity solutions for the three-dimensional (3D) target motion analysis problem using azimuth/elevation angles. A 3D pseudolinear estimator (PLE) is developed based on an approximation of the maximum likelihood (ML) cost function. Drawing on a large-sample bias analysis, a bias-compensated PLE is constructed. The concept of instrumental variables (IV) is employed to derive an asymptotically unbiased estimator. Finally a weighted IV estimator is developed to achieve an estimation performance close to the ML estimator (MLE).