Multi-user multiple-input, multiple-output (MU-MIMO) designs can substantially increase wireless systems' achievable throughput and connectivity capabilities. However, existing MU-MIMO deployments typically utilize linear processing techniques that, despite their practical benefits, such as low computational complexity and easy integrability, can leave much of the available throughput and connectivity gains unexploited. They typically require many power-intensive antennas and RF chains to support a smaller number of MIMO streams, even when the transmitted information streams are of low rate. Alternatively, non-linear (NL) processing methods can maximize the capabilities of the MIMO channel. Despite their potential, traditional NL methods are challenged by high computational complexity and processing latency, making them impractical for real-time applications, especially in software-based systems envisioned for emerging Open Radio Access Networks (Open-RAN). Additionally, essential functionalities such as rate adaptation (RA) are currently unavailable for NL systems, limiting their practicality in real-world deployments. In this demo, we present the latest capabilities of our advanced NL processing framework (NL-COMM) in real-time and over-the-air, comparing them side-by-side with conventional linear processing. For the first time, NL-COMM not only meets the practical 5G-NR real-time latency requirements in pure software but also does so within a standard-compliant ecosystem. To achieve this, we significantly extended the NL-COMM algorithmic framework to support the first practical RA for NL processing. The demonstrated gains include enhanced connectivity by supporting four MIMO streams with a single base-station antenna, substantially increased throughput, and the ability to halve the number of base-station antennas without any performance loss to linear approaches.

翻译：多用户多输入多输出（MU-MIMO）设计能够显著提升无线系统的可达吞吐量与连接能力。然而，现有的MU-MIMO部署通常采用线性处理技术，尽管这些技术具有计算复杂度低、易于集成等实际优势，却可能无法充分利用可用的吞吐量与连接增益。它们通常需要大量高功耗的天线与射频链来支持较少数量的MIMO流，即使传输的信息流速率较低。相比之下，非线性（NL）处理方法能够最大化MIMO信道的潜力。尽管具备潜力，传统的非线性方法因高计算复杂度与处理延迟而面临挑战，使其难以应用于实时场景，尤其是在为新兴开放无线接入网（Open-RAN）设想的基于软件的系统中。此外，非线性系统目前尚缺乏速率适配（RA）等关键功能，限制了其在实际部署中的实用性。在本演示中，我们展示了先进非线性处理框架（NL-COMM）在实时与空口环境下的最新能力，并将其与传统线性处理进行并列比较。NL-COMM首次不仅在纯软件环境中满足实用的5G-NR实时延迟要求，而且是在符合标准的生态系统内实现这一目标。为此，我们大幅扩展了NL-COMM算法框架，以支持首个适用于非线性处理的实用速率适配方案。所展示的增益包括：通过单基站天线支持四条MIMO流以增强连接性、吞吐量的大幅提升，以及在不损失线性方法性能的前提下将基站天线数量减半的能力。