摘要
For K-best multiple-input multiple-output (MIMO) detection using real-valued decomposition (RVD), we need to obtain the <inline-formula> <tex-math notation="LaTeX"> K</tex-math></inline-formula> surviving candidates from <inline-formula> <tex-math notation="LaTeX"> K √M̅</tex-math></inline-formula> candidates, where <inline-formula> <tex-math notation="LaTeX"> M</tex-math></inline-formula> is the modulation order. This paper presents a sorter-free detection algorithm, where the <inline-formula> <tex-math notation="LaTeX"> K</tex-math></inline-formula> surviving nodes can be obtained in <inline-formula> <tex-math notation="LaTeX"> \mathrm log₂ K</tex-math></inline-formula> iterations, which is independent of modulation size. The <inline-formula> <tex-math notation="LaTeX"> K √M̅</tex-math></inline-formula> candidates are arranged into a multiple-layer table using the proposed path metric discretization. A bisection-based search algorithm is used to obtain the locations of the <inline-formula> <tex-math notation="LaTeX"> K</tex-math></inline-formula> surviving candidates. A low-complexity fully-pipelined architecture is devised in order to implement the proposed MIMO detection without the need to use any dividers. In addition, an efficient method for storing information from child nodes is proposed, which requires significantly less storage space compared to the conventional Schnorr Euchner (SE) enumeration approach. Implementation results show that the proposed K-best MIMO detector supports a 6.4Gb/s throughput that has a <inline-formula> <tex-math notation="LaTeX"> 0.32 \boldsymbol{μ }{\text{s}{<}{/}}{t}ex-math></inline-formula> latency in a 90 nm process for a 256-quadrature amplitude modulation (QAM) 4<inline-formula> <tex-math notation="LaTeX"> × </tex-math></inline-formula>4 MIMO system. In addition, compared to the sorter-based baseline detector, the proposed detector improves the hardware efficiency by 77%.