A simple complexity adjustment technique for soft MIMO receivers in broadcasting scenarios

In multiple-input multiple-output (MIMO) broadcasting scenarios with spatial multiplexing, different users may experience diverse transmission environments. While users experiencing “unfavorable” transmission conditions employ advanced, soft receiver processing to achieve the required error-rate performance, it is a significant waste of resources (e.g., energy, latency) for users operating under good transmission scenarios. In order to avoid this unnecessary processing a very simple but efficient technique is proposed to adjust the receiver processing requirements to the transmission scenario and the targeted error-rate performance, without necessitating the exact relationship between complexity and performance. It applies aposteriori probability (APP) receivers operating over multiple-input multiple-output channels and it can provide significant complexity savings with only minor modifications on the originally proposed receivers.