PUF-based Authentication and ISAC Toward Hyper-Connectivity

Abstract

In hyper-connected wireless networks, numerous devices and signals interact simultaneously, making it essential to reliably authenticate devices and prevent spoofing attacks. At the same time, existing wireless infrastructures inherently carry rich in- formation from radio-frequency (RF) propagation, which can be used to extend com- munication functionality with sensing capabilities without requiring additional hard- ware. Motivated by these two aspects, this dissertation explores methods for leveraging unique physical-layer information for device authentication and spatial awareness. In terms of security, this dissertation investigates two device authentication approaches grounded in physical unclonable functions (PUFs). Wireless channels reflect spatial configurations and stochastic RF propagation behaviors, forming unpredictable and unclonable signatures. As a result, channel state information (CSI) serves as an effective indicator for identifying devices and detecting spoofing attempts during communication. This channel-based unclonability enables device authentication using only existing wireless infrastructure. Meanwhile, manufacturing variations imprint inher- ent physical uniqueness in hardware, resulting in hardware-based PUFs that generate stable and device-specific responses. These responses provide a fundamental physical root-of-trust for verifying decentralized identifiers in distributed networks. In terms of communication capability enhancement, wireless signals inherently pos- sess a dual role. They deliver information while simultaneously reflecting physical at- tributes of the environment. Building on this duality, this dissertation proposes an in- tegrated sensing and communication (ISAC) based on a time-switched multi-antenna architecture. By interpreting phase and amplitude differences across antennas as spatial features, the system estimates receiver locations in indoor environments. This demon- strates that existing wireless infrastructure can be used as a spatially aware communi- cation resource without additional sensing hardware. Finally, the proposed CSI-based RF authentication, hardware-based PUF authen- tication, and ISAC-based spatial recognition methods are experimentally validated across multiple hardware platforms and realistic wireless environments. Together, they show strong robustness against spoofing, stability under environmental variations, and practical feasibility for improving both security and communication utility in hyper- connected wireless networks. This dissertation presents a unified design perspective that combines physical-layer recognition with extended communication capabilities. ©2026 Seungnam Han ALL RIGHTS RESERVED