Channel Estimation in Constant Envelope Orthogonal Frequency-Division Multiplexing

Recently, Constant Envelope Orthogonal Frequency-Division Multiplexing (CE-OFDM) has been considered as a promising transmission scheme for next generation mobile communications and radar applications due to its 0 dB peak to average power ratio (PAPR) and its inherent benefits to mobile transmitters and their power amplifiers. However, the issue of channel estimation in CE-OFDM still needs to be addressed. This is crucial, as the performance of the equalizer, the coding and synchronisation in the communications system depends on the quality and accuracy of the channel estimate and channel state information (CSI). A novel channel estimation method needs to be implemented and adapted to CE-OFDM; doing this would add significance to CE-OFDM and enable a direct comparison to currently implemented systems, making it easier to equate conventional modulation techniques to CE-OFDM. Similarly, the effect of imperfect channel state information on the performance of CE-OFDM needs to be addressed. After adaptation and implementation of various proposed novel channel estimation techniques in CE-OFDM, a performance gain comparison and evaluation over fast fading channels can be presented and discussed.