Toward Communication-Efficient Space Data Centers: Bottlenecks, Architectures, and New Paradigms

2026-05-12

AI Summary

This work addresses the challenge of constrained data transmission for large-scale AI tasks in space due to limited ground-to-orbit communication bandwidth. To overcome this bottleneck, the study proposes a novel orbital data center architecture that integrates semantic communication with a multi-layer heterogeneous satellite network comprising relay and in-orbit computing nodes. By transmitting semantic information instead of raw data, the approach substantially reduces uplink traffic. A coupled energy–thermal management model is introduced to evaluate system feasibility. The first comprehensive analysis demonstrates that, under gigabit-class ground-to-orbit links, the proposed architecture can support petabyte-scale internal data exchange, thereby establishing a foundation for scalable and energy-efficient orbital AI systems.

Abstract

The rapid growth of foundation model training and large-scale AI services has driven ground data centers toward unprecedented power densities, intensifying challenges in energy supply, cooling, and spatial scalability. Space Data Centers (SDCs) have emerged as a promising paradigm for hosting energy-intensive computing infrastructures in orbit, leveraging continuous solar energy and radiative cooling advantages. However, unlike ground facilities primarily constrained by power and site availability, SDCs are fundamentally limited by communication capability. The gap between petabit-scale internal data exchange in ground data centers and the gigabit-scale capacity of ground-space links forms a critical bottleneck. This article systematically analyzes communication constraints in SDC architectures and explores semantic communication as a key enabling paradigm. By transmitting compact, task-relevant semantic representations instead of raw data, uplink pressure can be substantially reduced. The feasibility of communication-efficient orbital AI infrastructures is demonstrated through the evaluation of a multi-layer heterogeneous SDC framework consisting of relay satellites and orbital computing nodes operating under coupled energy and thermal constraints. The article further outlines open research challenges toward scalable deployment.

Problem

• Space Data Centers
• communication bottleneck
• ground-space links
• semantic communication
• orbital computing

Innovation

• Semantic Communication
• Space Data Centers
• Communication Efficiency
• Orbital AI Infrastructure
• Heterogeneous Satellite Architecture