Capacity Analysis of LEO Mega-Constellation Networks

Abstract

This paper proposes a complete network capacity analysis framework for Low-Earth-Orbit (LEO) mega-constellations, where a network capacity estimation problem considering the link packet loss rate is formulated with the support of the time-variant network topology model and the task distribution model. The problem is solved in two steps. Firstly, without considering the link packet loss rate, an improved fullypolynomial-time approximation (IFPTA) algorithm is proposed to give a sub-optimal solution of the multicommodity-flow (MCF) problem, in which a simpler definition of a commodity is given and proved to be equivalent to the original problem. Secondly, a Jackson-network-based capacity fallback approach is proposed for controlling link packet loss rate beneath a given threshold. Numerical results illustrate the superiority of the proposed IFPTA algorithm in accuracy and time complexity compared to existing solutions. In addition, the capacity characteristics of mega-constellations are analyzed by utilizing the proposed capacity analysis framework, including the relationship between constellation size and capacity, network capacity bottleneck, and influence of task distributions.INDEX TERMS LEO mega-constellation; network capacity; multi-commodity flow problem; Jackson network. I.

Federated Cell-Free MIMO in Nonterrestrial Networks: Architectures and Performance

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Load-Balancing Method for LEO Satellite Edge-Computing Networks Based on the Maximum Flow of Virtual Links

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