Quantum Annealing (QA)-accelerated MIMO detection is an emerging research approach in the context of NextG wireless networks. The opportunity is to enable large MIMO systems and thus improve wireless performance. The approach aims to leverage QA to expedite the computation required for theoretically optimal but computationally-demanding Maximum Likelihood detection to overcome the limitations of the currently deployed linear detectors. This paper presents \textbf{X-ResQ}, a QA-based MIMO detector system featuring fine-grained quantum task parallelism that is uniquely enabled by the Reverse Annealing (RA) protocol. Unlike prior designs, X-ResQ has many desirable system properties for a parallel QA detector and has effectively improved detection performance as more qubits are assigned. In our evaluations on a state-of-the-art quantum annealer, fully parallel X-ResQ achieves near-optimal throughput (over 10 bits/s/Hz) for $4\times6$ MIMO with 16-QAM using six levels of parallelism with 240 qubits and $220~\mu$s QA compute time, achieving 2.5--5$\times$ gains compared against other tested detectors. For more comprehensive evaluations, we implement and evaluate X-ResQ in the non-quantum digital setting. This non-quantum X-ResQ demonstration showcases the potential to realize ultra-large $1024\times1024$ MIMO, significantly outperforming other MIMO detectors, including the state-of-the-art RA detector classically implemented in the same way.

翻译：摘要：量子退火（QA）加速的MIMO检测是下一代无线网络研究中的新兴方向，旨在通过支持大规模MIMO系统提升无线性能。该方法利用QA加速传统最优但计算密集的最大似然检测所需的计算过程，突破当前线性检测器的性能瓶颈。本文提出\textbf{X-ResQ}——一种基于QA的MIMO检测系统，其独特利用了反向退火（RA）协议实现细粒度量子任务并行化。与现有设计相比，X-ResQ具备并行QA检测器的理想系统特性，且随着更多量子比特的分配，检测性能得到有效提升。在最新款量子退火器上的评估表明：采用六层并行化、240量子比特与$220~\mu$s QA计算时间的全并行X-ResQ，在$4\times6$ MIMO（16-QAM）场景下可实现接近最优的吞吐量（超过10 bits/s/Hz），较其他测试检测器获得2.5至5倍增益。为进行更全面的评估，我们在非量子数字环境中实现并测试了X-ResQ。该非量子X-ResQ的演示验证了实现超大规模$1024\times1024$ MIMO的潜力，其性能显著优于其他MIMO检测器，包括采用相同经典方式实现的最先进RA检测器。