LTE下行鏈路封包排程模擬器之研究

Abstract

近年來，長程演進技術(Long Term Evolution，LTE)已成為第四代行動通訊的無線系統，而國際電信聯盟(International Telecommunication Union，ITU)與第三代合作夥伴計畫(3rd Generation Partnership Project，3GPP)國際標準組織為了評估各種解決方法，已經開始訂定各種模擬規範，主要是用於複雜且具有整體驗證性質的系統層級模擬器(System level simulator, SLS)。系統層級模擬器LTE-Sim是一個開放源碼基於C++的模擬器，其設計理念是希望能完整實現演進型技術協定層，可提供完整的LTE網路性能驗證和讓研究人員進行修改，並用來了解LTE長程演進技術整體網路的效能，在本論文中，利用公平比例(Proportional Fairness，PF)、最大延遲優先(Maximum Largest Weighted Delay First，M-LWDF)和指數型公平演算法(Exponential Proportional Fairness，EXP/PF)，去評估LTE-Sim模擬器對於LTE系統的效能測試，例如：基地台平均傳輸速度、流量影響、使用者裝置、封包吞吐量、延遲和公平性等效能評估，並增加一個公平比較的模擬平台。

關鍵字：LTE-Sim模擬器、長程演進技術。In recent years, Long Term Evolution (LTE) has become the fourth generation mobile communication wireless system. System-Level Simulator (SLS) LTE-Sim is an open source C ++-based simulator designed to fully implement the protocol layers of LTE, providing a complete network performance verification and allowing researchers to modify the protocols. In this thesis, we use LTE-Sim to study the effeteness of different packet scheduling algorithms including the Proportional Fairness (PF), Maximum Largest Weighted Delay First (M-LWDF) and Exponential Proportional Fairness (Exponential Proportional Fairness, EXP / PF). From the simulation results, we provide a fair comparison of Quality of Service (QoS) metrics such as throughput, packet delay and packet loss rate with different packet scheduling algorithms in the LTE-Sim platform. By the analyses and solutions investigated in this work, we hope to thoroughly provide an in depth view about the design and implementation of the beyond 4G mobile communication system.

Keywords — LTE, LTE-Sim simulator.