Re-Transmission Diversity Multiple Access Based on SIC and HARQ-IR

We consider multiple access with re-transmission diversity (RTxD) based on a hybrid automatic request protocol with incremental redundancy (IR) in this paper. In order to mitigate multiple access interference, we employ successive interference cancellation at a receiver and derive conditions that all the signals from active users can be successfully decoded within a certain number of re-transmissions of IR blocks. We consider two special cases, which we derive from two multichannel random access schemes that have sub-channels in the power and rate domains. Through the analysis and simulations, we can show that the proposed RTxD random access schemes can outperform other existing similar RTxD random access schemes.