Frequency as Aperture: Enabling Embeddable Near-Field Sensing for 6G Wireless Radios

2026-01-29

AI Summary

This work addresses the challenge of integrating sensing and communication in cost- and power-constrained 6G nodes, where conventional millimeter-wave sensing relies on dedicated radar hardware incompatible with compact form factors. To overcome this limitation, the paper introduces a novel “Frequency-as-Aperture” (FaA) paradigm that shifts spatial sampling from the antenna domain to the frequency domain. By leveraging the inherent frequency agility of communication signals, FaA constructs a virtual sensing aperture using a single RF chain and a leaky-wave antenna. The approach reuses the communication local oscillator’s frequency-sweeping waveform, embedding radar-grade spatial sensing capability without increasing RF front-end complexity. This enables low-power, privacy-preserving, and embeddable integrated sensing and communication (ISAC) nodes. Under identical physical and spectral constraints, the proposed architecture significantly outperforms conventional multi-channel MIMO sensing in efficiency while achieving high-resolution near-field two-dimensional angle and range estimation, making it suitable for smart homes, wearable devices, and industrial edge applications.

Technology Category

• Intelligent Robots: Multimodal Perception & Sensor Fusion
• Application Domains: Internet of Things, Sensor Networks & Smart Cities
• Computer Vision: Multi-modal Vision

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Security and Privacy: Large-scale security measurements
• Search and Retrieval-Augmented AI: Personalized, context-aware and across-device search

Abstract

Integrated sensing and communication (ISAC) is expected to be natively supported by future 6G wireless radios, yet most mmWave sensing solutions still rely on dedicated radar hardware incompatible with cost and power constrained wireless nodes. This article introduces Frequency-as-Aperture (FaA), a wireless-first sensing paradigm that repurposes inherent frequency agility into a virtual sensing aperture, enabling near-field perception with minimal RF front end complexity. Using a single RF chain and a frequency-scanning leaky-wave antenna, FaA achieves two dimensional spatial sensing by reusing the local oscillator (LO) frequency sweep already employed for wideband communication. From a wireless-system perspective, this shifts spatial sampling from the antenna domain to the frequency domain, embedding radar-grade spatial fingerprints directly into the communication RF chain. A case study shows that FaA provides fine angular and range discrimination with low power consumption and unit cost, demonstrating significantly higher architectural efficiency than conventional multi-channel MIMO based sensing under identical physical and spectral constraints. These results indicate that near-field sensing can be seamlessly integrated into frequency-agile wireless radios, enabling hardware-efficient, embeddable, and privacy-preserving ISAC nodes for smart homes, wearables, and industrial edge deployments.

Problem

• Integrated Sensing and Communication
• Near-Field Sensing
• 6G Wireless Radios
• Hardware Efficiency
• Embeddable Sensing

Innovation

• Frequency-as-Aperture
• Integrated Sensing and Communication
• Leaky-Wave Antenna
• Near-Field Sensing
• Wireless-First Sensing