ANALYSIS OF A SIGNAL ESTIMATION ALGORITHM FOR DIVERSELY POLARIZED ARRAYS

We consider the problem of separating and estimating the waveforms of superimposed signals received by a diversely polarized array. Signal e stimation is accomplished by a two step procedure: 1) The direction of arrivals and polarization parameters of all the signals are estimated using an eigenstructure-based technique. 2) The estimated signal is o btained as a linear combination of the array outputs, with weights whi ch are computed from the estimated direction/polarization parameters. The objective of this paper is to analyze the quality of the estimated signal in terms of the output signal-to-interference ratio (SIR) and output signal-to-noise ratio (SNR). Closed form expressions are derive d for the output SIR and SNR of a general diversely polarized array. B y evaluating these expressions for selected test cases it is shown tha t polarization sensitive arrays can provide significantly higher outpu t SIR and SNR than uniformly polarized arrays. The performance improve ment is especially significant for closely spaced sources with suffici ently different polarization characteristics.