Advantages of superimposed packets allocation for OFDM-CDM

In this paper, superimposed packets allocation for orthogonal frequency-division multiplexing code-division multiplexing (OFDM-CDM) is presented. An iterative algorithm, which is a combination of parallel interference cancellation (PIC) and automatic repeat request (ARQ) based on soft value combining (SVC) is proposed and its performance studied and compared with other existing ARQ schemes. In the proposed algorithm, reliability information of erroneously received copies of the same data packet is exploited to improve the quality of interference cancellation. As a result, the proposed algorithm outperforms conventional ARQ based on a SVC as well as ARQ based on maximum ratio combining (MRC).