Selective angle measurements for a 3D-AOA instrumental variable TMA algorithm

The method of instrumental variables has been successfully applied to pseudolinear estimation for angle-of-arrival target motion analysis (TMA). The objective of instrumental variables is to modify the normal equations of a biased least-squares estimator to make it asymptotically unbiased. The instrumental variable (IV) matrix, used in the modified normal equations, is required to be strongly correlated with the data matrix and uncorrelated with the noise in the measurement vector. At small SNR, the correlation between the IV matrix and the data matrix can become weak. The concept of selective angle measurements (SAM) overcomes this problem by allowing some rows of the IV matrix and data matrix to be identical. This paper demonstrates the effectiveness of SAM for a previously proposed 3D angle-only IV TMA algorithm. The performance improvement of SAM is verified by simulation examples.