Frequency-domain iterative inter-code interference combined with parallel interference cancellation for cooperative-MIMO multi-code DS-CDMA

In future wireless communications, it is severe frequency-selective fading channel to support high data rate; meanwhile the available bandwidth becomes limited. To improve the spectrum-efficiency, one of the promising techniques is multiple input multiple output (MIMO) multiplexing technique. However, the space of one user terminal is limited, and it is difficult to accommodate more antennas in one terminal. Thus, cooperative communication is proposed, to achieve diversity and multiplexing gain via different user terminals. In this paper, a cooperative-MIMO based on multi-code direct sequence code-division multiple access (DS-CDMA) system is presented, which improves the spectrum efficiency a lot. However, the severely fading channel degrades the bit error rate (BER) performance of the proposed system significantly. The paper provided a frequency-domain iterative inter-code interference (ICI) combined with parallel interference cancellation (PIC) technology (ICP), which makes it possible to eliminate the interference between antennas and the residual inter-code interference between codes. From the simulation results, it is derived that the proposed method improves BER performance and the throughput of the system significantly.