Performance of an OFDM/FM scheme for data transmission over fading mobile radio channels

The Bit Error Rate (BER) performance of common data transmission schemes is quite poor when operating over the Rayleigh-fading mobile radio channel. This is due to the very high BER during fades. In (1) it is shown that Orthogonal Frequency Division Multiplexing (OFDM), a parallel transmission method, can provide improved performance by spreading the effects of a fade over many bits. This paper examines the performance of OFDM transmitted over an FM channel (OFDM/FM). Simulation results comparing OFDM/FM to Non-Coherent Frequency Shift Keying (NCFSK) indicate performance gains of 5 to 9 dB at a Bit Error Rate (BER) of 10^-3but negligible improvements at a BER of 10^-2.