Energy-Efficient MIMO Detection Using Link-Adaptive Parameter Adjustment

This paper presents a link-adaptive parameter adjustment scheme for energy efficient signal detection in multiple-input multiple-output (MIMO) systems. Equipped with multiple detection schemes of different performance-energy levels, the proposed detector adapts to instantaneous channel conditions and is adjusted at run-time with the detection scheme satisfying performance requirements with minimum power. To enable an efficient link adaptation, we develop a performance prediction method based on the equivalent SNR mapping technique. It provides accurate-enough BER estimation for non-linear signal detection under selectively fading channels. To demonstrate the effectiveness of the link adaptation technique on power saving, we carried out case studies by simulating a simplified LTE downlink system, where the parameter K of K-Best detection is adaptively adjusted. Simulation results demonstrate that the proposed link-adaptive detection offers significant power savings (53% on average and up to 86% for a 4×4 64-QAM system) compared to the static detection scheme targeting the worst-case environment.