直接通訊與間接通訊之連線管理機制

Abstract

在過去的幾年中，多媒體服務和其他資料密集服務的流量一直在快速成長，同時全世界的手機使用數量也不斷增加。這些現象讓近期在行動通訊網路上的研究也都以改善頻譜的使用效率與網路傳輸量為主要目標。而裝置間通訊(Device-to-device Communication; D2D Communication)被認為是一種很有前景的解決方案，其可達到提高無線資源使用效率、降低能量消耗、減輕基地台負擔並提供資料分流等優點。在長期演進技術(Long Term Evolution; LTE)網路中，D2D communication使用LTE的無線資源，並透過使用者設備(User Equipment; UE)上的LTE介面來發送和接收D2D communication。由於目前每個UE只配備了一個LTE介面，所以當有人播電話給正在進行的D2D communication的UE時會發生一個嚴重的問題，因為目前UE的LTE介面被D2D communication占用，所以UE無法及時接收來自核心網路(Core Network)傳來的來電通知。為了要解決此問題，我們提出了一個D2D連線管理機制，並利用UE的其他介面和D2D連線來傳遞來電通知。除此之外，我們更進一步採取上述的連線管理機制的概念，在網頁即時通訊(Web Real-Time Communicaiton; WebRTC)的環境實作出一個可以支援D2D功能的連線機制。

In the past few years multimedia and other data intensive traffic have been growing rapidly, as well as the number of mobile phones in usage through the world. Recent advances have been motivated towards improving spectral efficiency and throughput in cellular network. Device-to-device (D2D) communication is considered to be a promising solution to increase resource utilization, lower power consumption, ease base station load and provide data offloading. In the Long Term Evolution (LTE) network, the D2D communication technology reuses the radio resource and shares the LTE interface for the transmission and reception for D2D communications. However, because each UE is equipped with only one LTE interface, a serious problem may arise when someone is calling the user equipment (UE) in an ongoing D2D connection. Because the LTE interface is now being occupied by the D2D connection, the call notification from the core network cannot be timely received by the UE. To resolve this issue, we propose a connection management mechanism to route the call notification by utilizing other interfaces of UE and the D2D connection. We further take advantage of the idea of the proposed mechanism and implement the connection functions in the Web Real-Time Communication (WebRTC) environment to support D2D features.