多蜂巢多點協同下行傳輸網路下基於訊號干擾雜音比限制之強韌性自動重傳放大後中繼傳送設計

Abstract

中繼器輔助下之多點協同波束成形技術被研究用來提供在下行多細胞網路中自動重傳以支持服務質量。考慮到多點協同傳輸之設計限制和可行性，兩種類型的強韌性多點協同放大後中繼傳送波束成形技術被提出用來在通道資訊不完美下維持網路中每位使用者之訊號干擾雜音比。模擬結果顯示被提出的低複雜度演算法可以提供接近最佳的效能，並且透過多點協同中繼傳送技術，大大提高靠近細胞邊界之使用者的下行吞吐量。此外，被提出的強韌性多點協同波束成形技術不僅可以減低系統傳送所需的率，即使用低複雜度的放大後中繼傳送技術也仍然能增加自動重傳支持服務質量的可能性。

Relay-assisted coordinated multi-point (CoMP) beamforming (BF) methods are studied to support quality of service (QoS) in Automatic Retransmission reQuest (ARQ) for downlink multi-cell networks. Considering the design constraints and the feasibility of CoMP transmissions, two types of robust CoMP amplify-and-forward (AF) BF methods are proposed to maintain the signal to interference-plus-noise ratio for each subscriber station (SS) in the network subject to imperfect knowledge on the channel state information. Simulation results show that the proposed low-complexity algorithm can provide near optimal performance and the downlink throughput for SSs close to cell boundaries can be drastically improved via CoMP relaying. Besides, the proposed robust CoMP BF methods not only can reduce the system power consumption, but also can increase the feasibility to support QoS in ARQs even with the low-complexity AF relaying.