Frequency-hopping/M-ary frequency-shift keying for wireless sensor networks: Noncoherent detection and performance

In this paper, a novel WSN framework, namely the FH/MFSK WSN, is proposed, which monitors M-ary events and conveys signals from local sensors to fusion center with the aid of frequency-hopping (FH) and M-ary frequency-shift keying (MFSK) techniques. The source events under observation by local sensors are assumed to have M states. The estimates of local sensors are transmitted to the fusion center using MFSK modulation aided by FH. Channels from local sensors to fusion center are modelled either as additive white Gaussian noise (AWGN) channels or as Rayleigh fading channels. At the fusion center, signals are noncoherently detected based on square-law principles aided by equal gain combining (EGC). In this paper, the detection performance of the FH/MFSK WSN is investigated by simulation approaches. Our studies show that the FH/MFSK constitutes one of the promising schemes for efficient information delivery in WSNs. Reliable detection can be achieved at reasonable SNR levels for detection at local sensors and at fusion center.