Resource Slicing for Time-Sensitive Data Traffic in Non-Terrestrial Networks with FSO ISLs

Abstract

In multi-hop Low Earth Orbit (LEO) satellite networks, time-sensitive packets experience queueing across multiple satellite hops, causing per-hop waiting times that accumulate and make the maximum end-to-end (E2E) delay difficult to guarantee. This paper presents a novel multi-hop slicing framework that reserves time-frequency resources for each time-sensitive flow of data originating at each satellite, aiming to maintain the reservation of communication resources along every inter-satellite link (ISL) on its route to the ground station (GS). The number of time-frequency resource blocks (RBs) reserved per-hop is determined from the data packet arrival statistics, E2E delay budget, and target level of reliability. Reservations on consecutive links are temporally aligned to enable pipelined forwarding of the time-sensitive data flows aggregated from terrestrial user terminals on the different LEO satellites. We evaluate the proposed framework against conventional scheduling and resource-allocation baselines, including pure time-division multiple access (Pure-TDMA), first-in-first-out (FIFO), and farthest-satellite-first (FSF), over the same multi-hop LEO satellite path. Under light traffic conditions, the baseline schemes provide comparable delay performance; however, their high-percentile delays increase sharply as data traffic load grows, whereas the proposed framework exhibits substantially slower delay growth. At the high arrival rate and high reliability target considered, the proposed scheme requires about 31 ms, a factor of 2.5-6.8 lower than the 76, 180, and 210 ms required by FIFO, FSF, and Pure-TDMA.

arXiv comment6 pages, 7 figures, 1 table. Accepted for presentation at IEEE GLOBECOM 2026 Workshops