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.

翻译：集成感知与通信（ISAC）预计将成为未来6G无线射频的原生支持功能，然而目前大多数毫米波感知方案仍依赖专用雷达硬件，无法满足成本和功耗受限的无线节点需求。本文提出"频率即孔径"（FaA）这一无线优先的感知范式，通过将固有的频率捷变性重构为虚拟感知孔径，以极简的射频前端复杂度实现近场感知。FaA采用单射频链与频率扫描漏波天线，通过复用宽带通信中已有的本振（LO）频率扫描，实现二维空间感知。从无线系统视角看，该方法将空间采样从天线域转移至频域，将雷达级空间指纹直接嵌入通信射频链中。案例研究表明，在相同物理与频谱约束下，FaA能以低功耗和单元成本实现精细的角度与距离分辨能力，其架构效率显著高于传统基于多通道MIMO的感知方案。这些结果表明，近场感知可无缝集成于频率捷变无线射频中，为智能家居、可穿戴设备及工业边缘部署提供硬件高效、可嵌入式且保护隐私的ISAC节点。