Bandwidth efficient low complexity multiple turbo coded modulation on frequency-selective fading channels

As applications of wireless communications have grown in recent years, the development of high rate and reliable transmission schemes for band-limited mobile channels has become a major research goal. The combination of channel coding and multilevel signaling known as coded modulation can provide both very good error rate performance and high spectral efficiency for these channels. In this paper, we investigate a scheme using low complexity multiple turbo coded modulation with dense signal sets (16/32/64-QAM) and reduced-state soft-output MAP equalization on a frequency-selective fading channel, focusing on the rate 1/2 codes, thereby achieving spectral efficiencies of 2 bps/Hz, 2.5 bps/Hz, and 3 bps/Hz. The performance of the proposed system is evaluated by computer simulation.