Frequency-hopped multiple-access communication with noncoherent OFDM-MASK in AWGN channels

A noncoherent, bandwidth efficient modulation scheme is proposed for frequency hopping multiple access (FH-MA) networks. The proposed modulation scheme is a combination of noncoherent M-ary amplitude shift keying (MASK) and orthogonal frequency division multiplexing (OFDM). Using this modulation scheme minimizes the required data bandwidth. When compared to the conventional noncoherent scheme used in FH systems, i.e., M-ary frequency shift keying (MFSK), the number of frequency slots available to the users increases significantly for a fixed spread spectrum (SS) bandwidth. Therefore, the effect of multiple access interference (MAI) is reduced. Simulations and theoretical results show that significant MAI reduction can be achieved.