Security-Reliability Tradeoff Analysis of Spectrum-Sharing Aided Satellite-Terrestrial Networks

In this paper, we investigate the physical-layer security of a spectrum-sharing aided satellite-terrestrial integrated network comprised of a pair of satellite system and terrestrial system, which can utilize the shared spectrum in the presence of an eavesdropper. We propose a specifically designed satellite scheduling scheme to guarantee wireless transmission of the satellite system against eavesdropping attacks in the face of co-channel interference generated by the terrestrial communication system, where the specifically designed satellite scheduling scheme is represented by multi-satellite scheduling (MSS). We analyze the security-reliability tradeoff (SRT) of the MSS scheme, where the security and the reliability are characterized by the intercept probability and the outage probability, respectively. For comparison purposes, we also provide the SRT analysis of the round-robin satellite scheduling (RSS) scheme. In addition, numerical SRT results demonstrate that the proposed MSS scheme significantly outperform the RSS scheme in terms of their SRT.