Computational savings using nonlinear statistics in DOA estimation

The computational aspects related to sample estimation of moments involving certain "piecewise" nonlinearities are addressed with application to DOA estimation. In particular, the accuracy vs. computational saving tradeoff associated to "soft-limiting" nonlinearities can be exploited to simplify the computation of sample covariances without resulting in significative accuracy loss. It is also shown how, in sample cumulants evaluation, this approach can be employed to reduce the overall number of arithmetic operations using nonlinearities which act separately on the real and the imaginary parts of complex numbers.