基於4G核心網路的VoLTE研究與實現

Research and Implementation of VoLTE Based on 4G EPC

陳柏廷(Bo-Ting Chen)

指導教授 ： 黃紹華

國立交通大學/電機學院/電信工程系所/碩士(2020年)

摘要

目前使用的第四代行動通訊網路(The fourth generation mobile networks, 4G)，雖然在語音通話設計上使用PS(Packet Switch)的技術，也就是VoLTE(Voice Over LTE)，但大多數使用者還是會退回3G(The third generation mobile networks)透過CSFB (Circuit Switch Fallback)使用CS(Circuit Switch)的技術來進行通話，但當3G頻譜收回時，就必須使用VoLTE通話，本論文透過實作VoLTE系統來了解實際運作時的情況。本論文藉由修改已有部分功能的4G核心網路系統以及自行設計的IP多媒體子系統(IP Multimedia Subsystem, IMS)來實現VoLTE的功能，其中主要用到的通訊協議有S1AP(S1 Application Protocol)、NAS(Non Access Stratum)和SIP(Session Initiation Protocol)等，使用市面上能支持VoLTE的手機作為實驗的UE端，透過本論文設計的VoLTE系統讓手機能夠藉由4G基地台向架設好的IMS註冊並且使用通話功能，希望能藉由此論文實作的經驗作為未來設計第五代行動通訊網路(The fifth generation mobile networks, 5G)的語音通話VoNR(Voice over New Radio)系統基礎。

關鍵字

第四代行動通訊 ； 核心網路

並列摘要

Currently, the fourth generation mobile networks (4G) use PS (Packet Switch) technology for voice call design, which is VoLTE (Voice over LTE), but most users still Returning to 3G (The third generation mobile networks) uses CS (Circuit Switch Fallback) to use CS (Circuit Switch) technology to make calls, but when 3G spectrum is recovered, VoLTE calls must be used. This paper understands by implementing VoLTE system The situation in actual operation.In this paper, the functions of VoLTE are realized by modifying the existing 4G core network system and the self-designed IP Multimedia Subsystem (IMS). The main communication protocols used are S1AP (S1 Application Protocol), NAS (Non Access Stratum) and SIP (Session Initiation Protocol), etc., use mobile phones that can support VoLTE on the market as the UE terminal of the experiment. The VoLTE system designed in this paper allows mobile phones to register with the installed IMS through the 4G base station. And using the call function, I hope that the experience implemented from this paper can be used as the basis for the future design of the Voice over New Radio (VoNR) system of the fifth generation mobile networks (5G).

並列關鍵字

VoLTE ； EPC ； IMS

參考文獻

[1] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks , R. , Handley, M. , and E. Schooler , “SIP: Session Initiation Protocol”, IETF RFC 3261, June 2002.

[2] Niemi, A., Arkko, J., and Torvinen, V., “Hypertext transfer protocol (HTTP) digest authentication using authentication and key agreement (AKA)”. IETF RFC 3310, September 2002.

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[4] Linn, J., “Privacy Enhancement for Internet Electronic Mail, Part I: Message Encryption and Authentication Procedures”, IETF RFC 1421, February 1993.

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