High-throughput sorted MMSE QR decomposition for MIMO detection

The sorted QR decomposition (SQRD) has become a critical prerequisite for non-linear detection algorithms such as K-best and sphere decoding for multiple-input multiple-output (MIMO) systems. However, due to the sorting and norm updating procedures, these systems are difficult to achieve high-throughput applications for lack of efficiency and parallelism. In this paper, an efficient VLSI implementation combining modified array architecture with sorting operations is proposed to increase parallel processing abilities. In addition, a novel sorting look ahead updating scheme is employed to advance sorting operations, which reduces the processing latency. Moreover, ℓ¹-norm is adopted instead of the original ℓ²-norm to further simplify the hardware complexity. The proposed SQRD preprocessor implemented in SMIC 0.13μm CMOS technology achieves the throughput up to 25×106 SQRD per second which outperforms other works with equal functionality.