A soft decision decoding scheme for wireless COFDM with application to DVB-T

This paper investigates the soft decision decoding techniques for wireless COFDM systems. A new method to estimate the channel state information (CSI) for the Viterbi decoder is proposed, which overcomes the problem of reliability metric of transmitted signals in wireless as well as mobile channels. The CSI for each subcarrier is calculated as a properly defined squared Euclidean distance. On the basis of which, a soft decision decoding scheme to improve reception performance under multipath fading interference and co-channel interference (CCI) from existing analog broadcasting signals is also proposed. The simulation results show that the scheme can provide a compatible improvement to the terrestrial digital video broadcasting (DVB-T) system. The proposed scheme is also suitable for other wireless COFDM transmission systems.