小細胞雲端無線接取網路之合作式通訊與仿真機制

Abstract

為了服務爆炸性成長的無線通訊資料流量，小細胞基地台由於低傳送功率、較均勻訊號強度分布與較佳訊號品質等性質已成為下一代行動通訊的主流之一。然而由於小細胞基地台隨意且高密度的佈建方式，使得各基地台的通訊會彼此嚴重干擾。本篇論文依兩種方向討論如何改善系統傳輸效能。第一種方向是在雲端作中央式通道與功率配置，盡可能滿足多數上下行通訊連結。當通訊流量劇烈增減時，我們提出的小細胞雲端無線接取網路能動態調節適當雲端資源。第二種方向是多個基地台能合作處理上行通訊。對此，我們提出一種從接收端數據取得實體層的訊息的構想。我們希望基於此方法未來能夠構築出一套廣泛適用於數據通訊接收器的合作方式。除此之外，為了驗證雲端無線接取網路能夠即時地服務真實行動通訊需求，我們建構了用戶、基地台與網路的仿真系統對雲端實際施加大量通訊需求並量測其反應。

To serve the rapidly increasing mobile communication traffic, small cell networks are considered as one of the popular solutions for the next generation communication system as because it requires less transmission power and renders a more uniform signal coverage and better received signal quality. However, the communication traffic of small cell APs would interfere with one another due to the dense and random AP layout. Two ways are discussed to improve the overall system throughput. The first way is to grant as many downlink and uplink links as possible by centralized channel and power allocation in Cloud. The proposed small cell Cloud radio access network can scale its Cloud resource with rapidly increasing or decreasing communication traffic. The second way is that multiple APs cooperate for uplink communications. For this topic, we proposed an idea to extract physical layer information from binary stream. We hope this idea will develop into a new cooperation fashion for all kinds for receivers. Besides, to verify that the proposed small cell Cloud radio access network can handle real traffic in time, we construct a system to emulate APs and mobile users and their communication requests to Cloud and measure large amounts response of the proposed Cloud radio access network.