Graph-Based User Scheduling Algorithms for LEO-MIMO Non-Terrestrial Networks


Ahmad B., Riviello D. G., Guidotti A., Vanelli-Coralli A.

2023 Joint European Conference on Networks and Communications and 6G Summit, EuCNC/6G Summit 2023, Gothenburg, İsveç, 6 - 09 Haziran 2023, ss.270-275, (Tam Metin Bildiri) identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Doi Numarası: 10.1109/eucnc/6gsummit58263.2023.10188287
  • Basıldığı Şehir: Gothenburg
  • Basıldığı Ülke: İsveç
  • Sayfa Sayıları: ss.270-275
  • Anahtar Kelimeler: Beamforming, LEO, MMSE, MU-MIMO, User Scheduling
  • Orta Doğu Teknik Üniversitesi Kuzey Kıbrıs Kampüsü Adresli: Hayır

Özet

In this paper, we study the user scheduling prob-lem in a Low Earth Orbit (LEO) Multi-User Multiple-Input-Multiple-Output (MIMO) system. We propose an iterative graph-based maximum clique scheduling approach, in which users are grouped together based on a dissimilarity measure and served by the satellite via space-division multiple access (SDMA) by means of Minimum Mean Square Error (MMSE) digital beamforming on a cluster basis. User groups are then served in different time slots via time-division multiple access (TDMA). As dissimilarity measure, we consider both the channel coefficient of correlation and the users' great circle distance. A heuristic optimization of the optimal cluster size is performed in order to maximize the system capacity. To further validate our analysis, we compare our proposed graph-based schedulers with the well-established algorithm known as Multiple Antenna Downlink Orthogonal clustering (MADOC). Results are presented in terms of achievable per-user capacity and show the superiority in performance of the proposed schedulers w.r.t. MADOC.