Various parametric receivers such as the maximum likelihood and the hard-limiter have been analyzed for their performance in decoding the frequency hopped multilevel FSK (FH-MFSK) messages in mobile environment. Here, some nonparametric receivers such as the maximum rank sum receiver (MRSR) and the reduced rank sum receiver (RRR) are considered. RRR and MRSR are nearly identical in performance, but the former is much simpler to implement. The results indicate that RRR is a competing alternative to the parametric receivers.
Viswanathan, R. and Gupta, S. C. "Nonparametric Receiver for FH-MFSK Mobile Radio." (Feb 1985).