Learning Successive Interference Cancellation for Low-Complexity Soft-Output MIMO Detection

TL;DR

This paper introduces recurSIC, a lightweight machine learning-based MIMO detection framework inspired by SIC, capable of providing reliable soft information with minimal complexity suitable for edge devices in modern wireless systems.

Contribution

The paper presents recurSIC, a novel low-complexity, learning-based MIMO detector that efficiently generates soft information using multi-path hypothesis tracking with a single forward pass.

Findings

Achieves strong hard and soft detection performance

Operates with very low computational complexity

Suitable for edge-constrained MIMO receivers

Abstract

Low-complexity multiple-input multiple-output (MIMO) detection remains a key challenge in modern wireless systems, particularly for 5G reduced capability (RedCap) and internet-of-things (IoT) devices. In this context, the growing interest in deploying machine learning on edge devices must be balanced against stringent constraints on computational complexity and memory while supporting high-order modulation. Beyond accurate hard detection, reliable soft information is equally critical, as modern receivers rely on soft-input channel decoding, imposing additional requirements on the detector design. In this work, we propose recurSIC, a lightweight learning-based MIMO detection framework that is structurally inspired by successive interference cancellation (SIC) and incorporates learned processing stages. It generates reliable soft information via multi-path hypothesis tracking with a tunable complexity parameter while requiring only a single forward pass and a minimal parameter count. Numerical results in realistic wireless scenarios show that recurSIC achieves strong hard- and soft-detection performance at very low complexity, making it well suited for edge-constrained MIMO receivers.