以多連線技術均衡低軌道衛星網路之負載

Abstract

在未來6G通訊中，非地面網路是一項關鍵技術，能有效提升全球網路的覆蓋範圍。然而，有鑑於非地面網路的頻譜資源本就較地面網路稀少，當使用者數量隨著技術普及而增加時，其分布也將趨向不均勻，使平衡網路負載成為一大挑戰。為了解決上述問題，本研究提出使用多連線技術(Multi-Connectivity)增加連線的彈性，並建構了一個能同時決定連線與頻寬分配的最佳化問題，其中進一步考量了饋線鏈路(Feeder Link)容量限制與連線更新的成本。為了求解該混合整數非線性規劃問題(Mixed-Integer Nonlinear Programming)，本論文設計了一個分數捨入(fractional rounding)演算法得出次最佳解。經模擬結果驗證，我們的演算法在使用者傳輸量的公平程度與系統總通量都比基本的連線分配方法有更佳的表現。

Non-Terrestrial Network (NTN) plays a crucial role in the future 6G to provide ubiquitous coverage. However, as the number of users increases, the uneven distribution of user terminals (UTs) poses a challenge to balance the network load. To efficiently allocate the scarce resource in NTN, we propose to introduce diversity by Multi-Connectivity (MC) and formulate a joint user association and bandwidth allocation optimization problem considering feeder link (FL) capacity and association addition/migration cost. To cope with the mixed-integer nonlinear programming (MINLP), a fractional rounding algorithm is presented. The simulation results show the superiority of our proposed scheme over baselines in terms of user data rate fairness and total system throughput.