Pinching antenna systems improve covert rates in noma networks
Exploiting Pinching Antenna Systems in NOMA Covert Communication Networks
Information Theory
Summary
Keeping wireless messages hidden from eavesdroppers is hard, especially when multiple users share the same signals. This paper studies a special antenna system called pinching antennas that can better disguise signals sent to two users at once. The authors analyze how well hidden these signals can be against two watchers trying to detect them, and they find formulas to measure detection errors. Their results show that using pinching antennas with non-orthogonal multiple access can send more secret data than traditional methods, especially benefiting the user closer to the transmitter.
What this means in practice
- •For wireless network engineers: Deliver covert downlink communications with improved rates by integrating pinching antenna systems in non-orthogonal multiple access setups for multi-user scenarios.
- •For security system developers: Enhance stealthy communication channels in constrained environments by applying antenna configuration strategies that increase detection errors of passive monitors.
Authors
Xinwei Yue, Hao Li, Jingjing Zhao, Xianfu Lei, Yuanwei Liu
Abstract
Pinching antenna systems (PASS) provide flexible transmitter-side radiation reconfiguration for high-frequency wireless communications. This paper applies PASS to non-orthogonal multiple access (NOMA) covert communication networks, where activated pinching antennas (PAs) transmit superimposed signals to a pair of users stochastically distributed within a rectangle. Two passive wardens respectively monitor the downlink transmissions intended for two users. More specifically, we derive the closed-form detection error probability (DEP) expressions for two wardens under bounded noise uncertainty. Then we analytically determine the optimal detection thresholds and minimum DEPs in the worst-case covert detection scenarios. The covert transmission rates of two users are further characterized by taking into consideration ideal successive interference cancellation and non-ideal successive interference cancellation at near user and intra-NOMA interference at far user. Numerical results are presented to confirm that: 1) PASS-NOMA is capable of providing higher covert rates relative to conventional orthogonal multiple access OMA schemes; 2) As the number of activated PAs begun to increase, the near user has ability to obtain a larger covert rate gain than far user; and 3) The DEP of PASS-NOMA networks is larger than that of both PASS-OMA and traditional antenna (TA) based NOMA in specific output power regions.