A decoupled approach to adaptive signal separation using an antenna array

This paper considers a new approach to the problem of adaptive separation of digitally modulated signals arriving at an antenna array. The basic idea is to decouple the estimation procedure, treating one signal at a time to be the signal of interest. The method uses an iterative scheme similar to the well-documented iterative least squares with projection (ILSP) algorithm, exploiting the finite alphabet (FA) property of the signals to obtain signal estimates. The proposed algorithm is analyzed in terms of consistency and uniqueness properties, and a statistical performance analysis is carried out. The analysis together with simulation results indicate that a significant saving in computational complexity is accomplished relative to ILSP, while essentially having similar performance.

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