Hurry: Dynamic Collaborative Framework For Low-orbit Mega-Constellation Data Downloading

TL;DR

The paper addresses the challenge of rapidly downloading TB-scale space data from thousands of LEO satellites to ground stations within $3$–$5$ hours. It identifies Proximal Station Bias Degradation ($PSBD$) in the CoDld approach when scaling to Large-scale LEO Mega-Constellations and proposes Hurry, a dynamic framework that maps topology changes and data generation to Time-Expanded Graphs to generate transmission plans. The core contributions include a Min-Cost Max-Flow based flow-planning algorithm with an Adaptive Transmission Plan Update and a Generation Acceleration mechanism, validated in the Plotinus satellite digital twin showing $100\%$ completion in fixed data tasks and $11$–$66$\% throughput gains in continuous generation. These results demonstrate Hurry’s potential to enable scalable, timely ground processing for space data and motivate extensions to distributed learning, ISAC, and other LEO-network applications.

Abstract

Low-orbit mega-constellation network, which utilize thousands of satellites to provide a variety of network services and collect a wide range of space information, is a rapidly growing field. Each satellite collects TB-level data daily, including delay-sensitive data used for crucial tasks, such as military surveillance, natural disaster monitoring, and weather forecasting. According to NASA's statement, these data need to be downloaded to the ground for processing within 3 to 5 hours. To reduce the time required for satellite data downloads, the state-of-the-art solution known as CoDld, which is only available for small constellations, uses an iterative method for cooperative downloads via inter-satellite links. However, in LMCN, the time required to download the same amount of data using CoDld will exponentially increase compared to downloading the same amount of data in a small constellation. We have identified and analyzed the reasons for this degradation phenomenon and propose a new satellite data download framework, named Hurry. By modeling and mapping satellite topology changes and data transmission to Time-Expanded Graphs, we implement our algorithm within the Hurry framework to avoid degradation effects. In the fixed data volume download evaluation, Hurry achieves 100% completion of the download task while the CoDld only reached 44% of download progress. In continuous data generation evaluation, the Hurry flow algorithm improves throughput from 11% to 66% compared to the CoDld in different scenarios.

Figures (7)

• Figure 1: Walker Delta satellite constellation and +Grid ISL structure
• Figure 2: The PSBD phenomenon and its consequences
• Figure 3: Overall architecture design for Hurry framework
• Figure 4: Layered network flow graph
• Figure 5: The evaluation process of Hurry