On Covert Communication with Noise Uncertainty

TL;DR

This paper introduces a statistical approach to evaluate covert communication's covertness by considering noise uncertainty distributions, moving beyond worst-case assumptions to provide more realistic assessments.

Contribution

It proposes new metrics for covertness that incorporate noise uncertainty distributions and analyzes the maximum achievable rate under these models.

Findings

New metrics for covertness considering noise distribution

Analysis of achievable rates under bounded noise uncertainty

Evaluation of covertness in unbounded noise models

Abstract

Prior studies on covert communication with noise uncertainty adopted a worst-case approach from the warden's perspective. That is, the worst-case detection performance of the warden is used to assess covertness, which is overly optimistic. Instead of simply considering the worst limit, in this work, we take the distribution of noise uncertainty into account to evaluate the overall covertness in a statistical sense. Specifically, we define new metrics for measuring the covertness, which are then adopted to analyze the maximum achievable rate for a given covertness requirement under both bounded and unbounded noise uncertainty models.