Outage Constrained Robust Secure Beamforming in Cognitive Satellite-Aerial Networks

TL;DR

This paper develops a robust beamforming method to improve physical layer security in cognitive satellite-aerial networks, effectively managing interference and power constraints despite imperfect channel information.

Contribution

It introduces a novel outage constrained robust beamforming scheme that maximizes secrecy rate under multiple practical constraints in satellite-aerial networks.

Findings

Proposed scheme enhances secrecy rate with increased transmit power.

Method effectively handles imperfect channel state information.

Simulation results validate the near-optimal performance of the scheme.

Abstract

This paper proposes a robust beamforming scheme to enhance the physical layer security (PLS) of multicast transmission in a cognitive satellite and aerial network (CSAN) operating in the millimeter wave frequency band. Based on imperfect channel state information (CSI) of both eavesdroppers (Eves) and primary users (PUs), we maximize the minimum achievable secrecy rate (ASR) of the secondary users (SUs) in the aerial network under the constraints of the interference to the PUs in the satellite network, the quality of service (QoS) requirements of the SUs and per-antenna power budget of the aerial platform. To tackle this mathematically intractable problem, we first introduce an auxiliary variable and outage constraints to simplify the complex objective function. We then convert the non-convex outage constraints into deterministic forms and adopt penalty function approach to obtain a semi-definite problem such that it can be solved in an iterative fashion. Finally, simulation results show that with the transmit power increase, the minimal ASR of SUs obtained from the proposed BF scheme well approximate the optimal value.