Effects of fast frequency hopping multiple access systems due to the frequency and timing offset under Rayleigh fading

In order to investigate effects of fast frequency hopping multiple access (FHH-MA) systems due to the frequency and timing offset, we evaluate the bit error rate (BER) performance of the FFH-MA system using noncoherent M-ary frequency shift keying (FSK) modulation in the Rayleigh fading channel. While the frequency or timing offset increases at a given SNR, the BER is severely degraded. When the system is affected only by either of two offsets, and normalized offset is less than 0.3, the timing offset has a worse influence upon the FFH-MA system than the frequency offset. For the SNR of more than 20 dB, the threshold level of the receiver suffering from the frequency and timing offsets should be greater than that of the perfectly synchronized receivers.