Green Interference Based Symbiotic Security in Integrated Satellite-terrestrial Communications

TL;DR

This paper proposes a green interference-based symbiotic security scheme for integrated satellite-terrestrial communications, enhancing secure transmission by cooperative beamforming and interference management.

Contribution

It introduces a novel security scheme leveraging green interference from spectrum sharing and beam reuse, with an optimization framework and solution algorithms.

Findings

The proposed method improves the sum secrecy rate of satellite users.

The approach guarantees the secrecy rate for terrestrial users.

Numerical results confirm the effectiveness of the scheme.

Abstract

In this paper, we investigate secure transmissions in integrated satellite-terrestrial communications and the green interference based symbiotic security scheme is proposed. Particularly, the co-channel interference induced by the spectrum sharing between satellite and terrestrial networks and the inter-beam interference due to frequency reuse among satellite multi-beam serve as the green interference to assist the symbiotic secure transmission, where the secure transmissions of both satellite and terrestrial links are guaranteed simultaneously. Specifically, to realize the symbiotic security, we formulate a problem to maximize the sum secrecy rate of satellite users by cooperatively beamforming optimizing and a constraint of secrecy rate of each terrestrial user is guaranteed. Since the formulated problem is non-convex and intractable, the Taylor expansion and semi-definite relaxation (SDR) are adopted to further reformulate this problem, and the successive convex approximation (SCA) algorithm is designed to solve it. Finally, the tightness of the relaxation is proved. In addition, numerical results verify the efficiency of our proposed approach.