PASS-Enabled Covert Communications With Distributed Cooperative Wardens

2026-01-12

arXiv.org

AI Summary

This work addresses the challenge of multi-guard joint detection in distributed cooperative surveillance by proposing a downlink covert communication scheme based on a dual-waveguide architecture. The approach simultaneously transmits covert signals and random interference, integrating three PASS power emission patterns to construct a system-level detectability analysis framework. For the first time, a closed-form expression for the system’s detection error probability is derived under a non-i.i.d. majority-vote fusion mechanism, accompanied by an efficient analytical method leveraging breakpoint partitioning and elementary symmetric polynomials. A robust optimization algorithm (MM-BCD-SCA) is developed by combining probability generating functions, convex surrogates, and inner approximation techniques. Numerical results validate the theoretical analysis, revealing the critical impact of cooperative surveillance and emission patterns on the covert rate trade-off and demonstrating a significant improvement in average covert communication rate.

Technology Category

• Search and Optimization: Mixed Discrete/Continuous Search
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization
• Game Theory and Economic Paradigms: Cooperative Game Theory

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• User Modeling, Personalization and Recommendation: User privacy protection in personalized systems

Abstract

This paper investigates PASS-enabled downlink covert communication in the presence of distributed surveillance, where multiple wardens perform signal detection and fuse their local binary decisions via majority-voting rule. We consider a dual-waveguide architecture that simultaneously delivers covert information and randomized jamming to hide the transmission footprint, incorporating three representative PASS power-radiation laws-general, proportional, and equal. To characterize the system-level detectability, we derive closed-form expressions for local false-alarm and miss-detection probabilities. By leveraging a probability-generating-function (PGF) and elementary-symmetric-polynomial (ESP) framework, combined with a breakpoint-based partition of the threshold domain, we obtain explicit closed-form characterizations of the system-level detection error probability (DEP) under non-i.i.d. majority-voting fusion. Building on this analytical framework, we formulate a robust optimization problem to maximize the average covert rate subject to covertness constraint. To solve the resulting nonconvex design, we develop an MM-BCD-SCA algorithm that produces tractable alternating updates for power/radiation variables and PA positions via convex surrogates and inner approximations of the DEP value function. Numerical results validate the theoretical analysis and demonstrate the impact of cooperative monitoring and PASS radiation laws on the covertness-rate tradeoff.

Problem

• covert communications
• distributed wardens
• majority-voting fusion
• PASS
• detectability

Innovation

• PASS-enabled covert communication
• distributed cooperative wardens
• majority-voting fusion
• detection error probability
• MM-BCD-SCA algorithm