Performance Analysis of the Dual-Hop Satellite-Terrestrial Network with Imperfect CSI and Direct Link

This paper presents an analysis of the performance of hybrid satellite-terrestrial relaying (HSTR) networks with user selection schemes. Specifically, we investigate the outage probability of the HSTR networks while accounting for the direct link and imperfect channel state information (CSI). Three user selection schemes are considered: direct link-based, indirect link-based, and end-to-end (e2e) based schemes. In the direct link-based scheme, the best user is selected based on the direct link's quality. The indirect link-based scheme selects the best user via the relay, while the end-to-end based scheme combines both links using selection combining techniques at the user. Numerical computations are provided to identify the most effective selection scheme and to highlight the impact of key parameters on performance metrics.