Towards Efficient Spectrum Sensing for 5G/B5G Communications Using Walsh Receivers

Spectrum sensing is a fundamental capability for Beyond fifth generation (B5G) and emerging sixth generation (6G) systems, enabling autonomous and reliable communications in highly dynamic and mission-critical environments. Applications such as maritime communications, border protection, and civil protection operations require low-complexity and energy-efficient receivers capable of identifying available spectrum and mitigating strong interferers in real time. Conventional spectrum sensing approaches often rely on wideband analog-to-digital converters and heavy digital signal processing, resulting in significant power and hardware overheads. In this paper, a new spectrum sensing method for 5G signals based on a Walsh receiver architecture is proposed. Unlike conventional approaches, the proposed scheme projects the incoming signal onto orthogonal Walsh codes directly in the analog domain, enabling massively parallel sampling and reducing the need for high-speed analog-to-digital converters (ADCs) . This architecture inherently supports per-lane gain control, which strengthens robustness against strong narrowband interferers and channel fading. Performance evaluation, in the context of 5G NR FR1 spectrum sensing and communication with overlapping WLAN signals, indicates that perfect signal reconstruction and satisfactory EVM are achieved under challenging interference conditions. The results demonstrate that Walsh receivers provide an efficient and scalable foundation for spectrum sensing in 5G and beyond.