VLSI Implementation of a Fully-Pipelined K-Best MIMO Detector with Successive Interference Cancellation

Abstract

Multiple-input multiple-output (MIMO) technology is envisaged to play an important role in future wireless communications. To this end, novel algorithms and architectures are required to implement high-throughput MIMO communications at low power consumption. In this paper, we present the hardware implementation of a modified K-best algorithm combining conventional K-best detection and low-complexity successive interference cancellation at different levels of the tree search. The detector is implemented using a fully-pipelined architecture, which detects one symbol vector per clock cycle. To reduce the power consumption of the entire receiver unit, costly symbol-rate operations such as multiplication are eliminated both within and outside the detector without any impact on the performance. The hardware implementation of the modified K-best algorithm achieves area and power reductions of 16% and 38%, respectively, compared with the conventional K-best algorithm implementation, while incurring a signal-to-noise ratio penalty of 0.3 dB at the target bit error rate. Post-synthesis analysis shows that the detector achieves a throughput of 3.29 Gbps at a clock frequency of 137 MHz with a power consumption of 357 mW using a 65-nm CMOS process, which compares favourably with the state-of-the-art implementations in the literature.