A demodulation complexity reduction method using M-algorithm for high compaction multi-carrier modulation systems

This paper proposes a demodulation method for high compaction multi-carrier modulation (HC-MCM) using the M-algorithm to reduce the calculation complexity for data recovering in the receiver. The performance of the proposed method is evaluated by the amount of Euclidean distance calculations in comparison with the maximum likelihood estimation (MLE). The bit-error rate (BER) characteristics of HC-MCM systems using proposed demodulation method are demonstrated by computer simulations in the presence of Gaussian noise. Performance of the HC-MCM using proposed demodulation method is also evaluated over a 2-path equal power Rayleigh fading channel. As a result, it is shown that the calculation complexity for 8 subcarriers is reduced to 0.6% in comparison with the MLE, and BER performance is not degraded even when the proposed system gives 64% increase of spectral efficiency in comparison with OFDM. In addition to those good properties, it is shown here that the proposed system is available over a wideband fading channel using a guard time interval.