{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:30:53Z","timestamp":1760059853457,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,7,15]],"date-time":"2025-07-15T00:00:00Z","timestamp":1752537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003626","name":"Agency for Defense Development","doi-asserted-by":"publisher","award":["UI237032TG"],"award-info":[{"award-number":["UI237032TG"]}],"id":[{"id":"10.13039\/501100003626","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JSAN"],"abstract":"<jats:p>Low Earth orbit (LEO) satellite networks deliver superior real-time performance and responsiveness compared to conventional satellite networks, despite technical and economic challenges such as high deployment costs and operational complexity. Nevertheless, rapid topology changes and severe energy constraints of LEO satellites make real-time routing a persistent challenge. In this paper, we employ field-programmable gate arrays (FPGAs) to overcome the resource limitations of on-board computers (OBCs) and to manage energy consumption effectively using the Eclipse-Aware Routing (EAR) algorithm, and we implement the K-Shortest Paths (KSP) algorithm directly on the FPGA. Our method first generates multiple routes from the source to the destination using KSP, then selects the optimal path based on energy consumption rate, eclipse duration, and estimated transmission load as evaluated by EAR. In large-scale LEO networks, the computational burden of KSP grows substantially as connectivity data become more voluminous and complex. To enhance performance, we accelerate complex computations in the programmable logic (PL) via pipelining and design a collaborative architecture between the processing system (PS) and PL, achieving approximately a 3.83\u00d7 speedup compared to a PS-only implementation. We validate the feasibility of the proposed approach by successfully performing remote routing-table updates on the SpaceWire-based SpaceWire Brick MK4 network system.<\/jats:p>","DOI":"10.3390\/jsan14040073","type":"journal-article","created":{"date-parts":[[2025,7,15]],"date-time":"2025-07-15T15:01:05Z","timestamp":1752591665000},"page":"73","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Parallel Eclipse-Aware Routing on FPGA for SpaceWire-Based OBC in LEO Satellite Networks"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-5471-7458","authenticated-orcid":false,"given":"Jin Hyung","family":"Park","sequence":"first","affiliation":[{"name":"School of Electronic Engineering, Kumoh National Institute of Technology, Gyeongbuk 39177, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2962-3474","authenticated-orcid":false,"given":"Heoncheol","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Electronic Engineering, Kumoh National Institute of Technology, Gyeongbuk 39177, Republic of Korea"},{"name":"Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gyeongbuk 39177, Republic of Korea"}]},{"given":"Myonghun","family":"Han","sequence":"additional","affiliation":[{"name":"Agency for Defense Development, Daejeon 34186, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"184955","DOI":"10.1109\/ACCESS.2020.3029620","article-title":"LEO Small-Satellite Constellations for 5G and Beyond-5G Communications","volume":"8","author":"Soret","year":"2020","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"31407","DOI":"10.1109\/JIOT.2024.3419264","article-title":"Joint UAV trajectory and power allocation with hybrid FSO\/RF for secure space\u2013air\u2013ground communications","volume":"11","author":"Zhang","year":"2024","journal-title":"IEEE Internet Things J."},{"key":"ref_3","first-page":"2277","article-title":"SpaceWire: A spacecraft onboard network for real-time communications","volume":"52","author":"Parkes","year":"2005","journal-title":"IEEE Trans. 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