Quadratic sphericity test for blind detection over time-varying frequency-selective fading channels

Abstract

This paper addresses the problema of blind detection of a wide-sensestationary (WSS) signal overfading channels.We propose a test statistic which isoptimal from a correlation matching perspective that shows invariance withrespect to the noise power and the channel gain. In the blind scenario, we derive the quadratic sphericity test (QST) which exploits the structure of the fàding channel as asquared mean to arithmetic mean ratio of the eigenvalues of the autocorrelation matrix of the observations. We provide numerical results to assess the performance of the QST inseveral fàding scenarios,as well as the benchmarking to other blind and non-blind detectors.