DCT/DST-based frequency modulated-OFDM

Among the recent advancements in waveform design for wireless communication, the frequency-modulated orthogonal frequency-division multiplexing (FM-OFDM) has gained attention due to its resilience to phase noise and Doppler spread, as well as its zero-dB peak-to-average power ratio (PAPR). We propose two alternative frequency-time conversion schemes based on discrete cosine transform (DCT) and discrete sine transform (DST) that can potentially supplant discrete Fourier transform (DFT) within FM-OFDM. Extensive simulations demonstrate that FM-OFDM waveforms utilizing DCT and DST can improve link performance compared to those based on DFT. Furthermore, employing frequency-domain spreading with DCT/DST-based FM-OFDM shows additional link performance enhancements. 2024 The Korean Institute of Communications and Information Sciences. Publishing Services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ).