A Rakeness Test for Coherent Signal Combining in Mobile Receivers

This work introduces the Rakeness test as a signal processing technique to assess the fitness of a cascaded coherent combining, such as implemented by a Rake receiver, or one simpler matched filter. Our testing procedure discriminates between one dominant path (detectable by a matched filter) and few dominant paths (possibly corresponding to the Rake fingers). This corresponds to measure how much the observed series (amplitude samples of matched filter receiver's output) fits Rice vs. non-Rice (e.g. Nakagami-m) models. This decision is made exploiting higher order statistics of the series under investigation. The achieved results, obtained throughout theory and simulations, have evidenced the efficiency of this innovative test to possibly start-up coherent combining.