Design and performance of an OFDM-CPM receiver for wireless communications

A new class of orthogonal frequency division multiplexing-continuous phase modulation (OFDM-CPM) signals has been introduced recently that outperforms conventional OFDM-PSK signals. These signals employ multi symbol observations for detection of data. An optimum OFDM-CPM receiver was designed that observed n symbols of the received waveform, and arrived at an optimum estimate of the data transmitted in the first symbol interval. However, from the viewpoint of receiver complexity, this receiver is quite complex and the complexity grows exponentially as a function of number of observation symbols. Thus, in this paper, we develop and investigate a less complex OFDM-CPM receiver that employs post-FFT signal processing for recovery of data. Performance of this receiver is evaluated over multipath fading channels for several subclasses of OFDM-CPM signals. It is shown that we achieve error rate performance that is far superior to the performance offered by conventional OFDM-PSK systems