Space-Terrestrial Cooperation Over Spatially Correlated Channels Relying on Imperfect Channel Estimates: Uplink Performance Analysis and Optimization

Abstract

A whole suite of innovative technologies and architectures have emerged in response to the rapid growth of wireless traffic. This paper studies an integrated network design that boosts system capacity through cooperation between wireless access points (APs) and a satellite for enhancing the network's spectral efficiency. As for our analytical contributions, upon coherently combing the signals received by the central processing unit (CPU) from the users through the space and terrestrial links, we first mathematically derive an achievable throughput expression for the uplink (UL) data transmission over spatially correlated Rician channels. Our generic achievable throughput expression is applicable for arbitrary received signal detection techniques employed at the APs and the satellite under realistic imperfect channel estimates. A closed-form expression is then obtained for the ergodic UL data throughput, when maximum ratio combining is utilized for detecting the desired signals. As for our resource allocation contributions, we formulate the max-min fairness and total transmit power optimization problems relying on the channel statistics for performing power allocation. The solution of each optimization problem is derived in form of a lowcomplexity iterative design, in which each data power variable is updated relying on a closed-form expression. Our integrated hybrid network concept allows users to be served that may not otherwise be accommodated due to the excessive data demands. The algorithms proposed allow us to address the congestion issues appearing when at least one user is served at a rate below his/her target. The mathematical analysis is also illustrated with the aid of our numerical results that show the added benefits of considering the space links in terms of improving the ergodic data throughput. Furthermore, the proposed algorithms smoothly circumvent any potential congestion, especially in face of high rate requirements and weak channel conditions.

Uplink Sum Throughput Analysis and Maximization for Integrated Satellite-Terrestrial Cell-Free Massive MIMO

“…An LEO satellite is placed at location (300, 300, 400) , respectively. The large-scale fading coefficients involve both the path loss and shadow fading as in [2], and the satellite beam patterns are modeled as in [6].…”

“…Satellites can provide an immediate solution to this issue by complementing terrestrial networks with ubiquitous connectivity [4]. Low orbit (LEO) satellites offer distinctive merits to connect terrestrial devices on the ground, which can communicate with objects with limited or no access to traditional terrestrial networks [5], [6]. Nonetheless, most related works assume perfect channel state information (CSI) and rely on optimization problems based on slow fading.…”

Security-Reliability Trade-Offs for Satellite-Terrestrial Relay Networks with a Friendly Jammer and Imperfect CSI

“…In the current work, we have shared the same satelliteterrestrial literature with the previous works [36], [37], especially the reliability and security issues [36]. However, this paper is more general than [36] since the fading channels are applied for arbitrary locations of the eavesdroppers and the destinations.…”