Efficient joint two-dimensional angle and polarization estimation with crossed dipoles

This paper addresses a fast algorithm for joint estimation of the two-dimensional (2-D) angles and polarization of the impinging signals based on a novel hierarchical spacetime decomposition (HSTD) technique. The proposed algorithm makes use of a sequence of one-dimensional (1-D) Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) algorithms to estimate these parameters alternatively in a hierarchical tree structure. Furthermore, a spatial beamforming process is invoked in between the 1-D ESPRIT algorithms to progressively partition signals into finer groups to enhance the estimation accuracy and to mitigate the contaminated noise. With such an ingenious tree-structured estimation scheme, the pairing of these parameters is automatically determined without extra hardware or computational cost. Simulation results show that the new algorithm provides satisfactory performance but calls for drastically reduced computations compared with previous works.