3.2 Gbps Channel-Adaptive Configurable MIMO Detector for Multi-Mode Wireless Communication

A configurable, channel-adaptive K-best multiple-input, multiple-output (MIMO) detector for multi-mode wireless communications that adapts computation to varying channel conditions to achieve high energy-efficiency is presented. An 8-stage configurable MIMO detector supporting up to a 4 × 4 MIMO array and BPSK to 16-QAM modulation schemes has been implemented and simulated in 0.80 V, 22 nm Tri-gate CMOS process. Dynamic clock gating and power gating enable on-the-fly configuration and adaptive tuning of search radius K to channel response which results in 10 to 51 % energy-efficiency improvement over non-adaptive K-best MIMO detectors. During unfavorable channel conditions, the MIMO detector satisfies target bit error rate (BER) by setting K = 5. For favorable channel conditions, K is reduced to 1, where 22 nm circuit simulations show 68 % energy reduction. At 1.0GHz target frequency, the total power consumption is 15 mW (K = 1) to 35 mW (K = 5), resulting in energy-efficiency of 14.2pJ/bit (K = 1) to 44.7pJ/bit (K = 5) and 3.2Gbps throughput.