An investigation of coded OFDM and CEOFDM waveforms utilizing different modulation schemes on HF channels

Constant envelope orthogonal frequency division multiplexing (CE-OFDM) is a modification to OFDM which eliminates the large peak power to average power ratio (PAPR) inherent in OFDM. For uncoded waveforms, CE-OFDM has been shown to offer some significant performance advantages over OFDM on high frequency (HF) multipath fading channels. However, when coding and interleaving are added to the waveforms, OFDM outperforms CE-OFDM on HF multipath fading channels, even after the PAPR of OFDM is included in the performance comparison. The results presented so far have only been for 2-ary phase shift keying (2-PSK) modulation. This paper will extend previous research by investigating the performance of coded OFDM and CE-OFDM waveforms using higher-order modulation schemes on various HF multipath fading channels.