Multi-LEO Satellite Networks for Integrated Access and Backhaul: Outage Performance Analysis

Low Earth Orbit Satellites (LEO-Sats) are considered to expand terrestrial network coverage, particularly in scenarios where ground users lack direct communication with ground base stations (BSs). However, in situations requiring reliable connectivity at specified data rates, establishing a network utilizing LEO-Sats over these users becomes necessary. This study investigates a LEO-Sat-network for integrated access and backhaul (IAB) within fifth-generation (5G) systems, wherein a LEO-Sat acts as an IAB node connecting with other IAB nodes for backhaul transmissions while serving as a BS for ground users. Analytical expressions for outage probabilities in both the backhaul link, comprising inter-LEO satellite communication, and access networks linking LEO satellites with ground users, are derived. The channel link in the access network is assumed to be a Nakagami fading channel, while the backhaul network is affected by only large scale fading. Numerical simulations are conducted to analyze the impact of transmission rate and LEO-Sat transmit power on the system’s outage probability, revealing trade-offs between data rate and reliability.