Investigating Frequency Modulated OFDM (FM-OFDM): Receiver Design and Analysis Over Time-Varying Channels

This paper provides a comprehensive analysis of Frequency Modulated Orthogonal Frequency Division Multiplexing (FM-OFDM), a novel modulation technique exhibiting good levels of robustness when employed on wireless communication links in high-mobility environments. A novel transceiver receiver design that eliminates the need for phase unwrapping, thereby reducing computational complexity, is proposed. Analytical performance of the modulation is assessed through mathematical derivation of closed-form expressions for the signal-to-noise ratio (SNR) per subcarrier. Such expressions provide in-depth understanding of both ideal and more realistic communication scenarios. Additionally, the paper also contains analytical derivations that permit to evaluate the power spectral density and bandwidth characteristics of the FM-OFDM modulation. Numerical results show the effectiveness of the FM-OFDM waveform in environments affected by large Doppler shifts, as well as the remarkable performance level of the newly proposed low-complexity detector.