Frequency-Domain Turbo Equalization for Single Carrier Mobile Broadband Systems

This paper investigates mobile broadband communications, which undergo time-varying radio channels with large multipath delay spread. Space-time block transmission and single carrier modulation are adopted at the transmitter to combat the inter-symbol interference resulted from, the multipath delay. The single carrier modems with frequency-domain equalization have similar performance and complexity as orthogonal frequency-division multiplexing, yet less sensitive to radio frequency impairments. At the receiver, we propose the turbo equalization that consists of a minimum mean-square error equalizer in the frequency domain and a channel decoder. In order to cope with the time-varying characteristics of the mobile channel, the received data is partitioned into blocks for the linear equalizer, and then combined as a decoding frame for the decoder. Simulation results show good performance of the proposed scheme with feasible computational complexity