第四代行動通訊系統測試技術:省電機制與語音通話品質量測

Abstract

第四代行動通訊標準LTE會經歷一系列不同階段的測試後才能產品化並上市銷 售。一般而言，任何通訊技術能夠運作，不外乎定義技術規範並執行一致性測試以驗 證產品是否符合LTE的技術規範。然而，儘管完成一致性的測試，各家對規範的不同 解讀可能無法保證每個用戶終端裝置與每個基地台能夠互相通訊，所以還需進行互通 性測試。除了這兩項基本測試可以確保LTE裝置能夠正常的在商用網路上使用外，使 用者重視的其實是各種應用服務的服務品質保證與電力消耗問題。

本計晝中，我們主要將針對LTE基本測試(一致性測試與互通性測試)與進階測試 (服務品質保證與省電效益)進行測試技術開發與研究議題探討。主要的目標為下：一、 為提供產業界終端裝置開發的測試需求，除了進行一致性測試案例分析外，還需要有 互通性測試案例設計與分析以節省終端裝置開發流程；二、為了達到終端裝置最好的 省電效益且兼顧應用服務的傳輸品質，我們必須要同時考量DRX省電機制與排程演算 法，找到一個較佳的DRX週期以使使用者裝置可以達到較佳的省電效益；三、為了反 應真實的通道狀況，我們亦須在排程演算法與省電機制設計中考量通道的效益所帶來 的影響。

主要貢獻包含：一、LTE基本測試需求-PCT案例分析與IOT測試案例設計；二、 開發省電機制測試與QoS/QoE測試驗證平台；三、考慮通道環境與DRX省電機制之 VoIP QoS排程演算法設計。預計可產出三篇國際論文、一件專利與IOT測試案例分析 報告。PCT測試與IOT測試案例分析可供產業界作為終端裝置開發與篩選終端裝置參 考依據；而省電機制測試與QoS/QoE驗證則可做為LTE系統設計之考量依據。

The 4th generation broadband mobile system (i.e., LTE) will experience a series of different tests to prove correct operations. In generally, all communication systems will define the technical specifications and perform the conformance test to verify that the product meets the specifications. However, the difference interpretations on the specifications from different vendors may not guarantee that all devices could communicate with each other. Therefore, the interoperability test is needed. In addition to these two basic testing requirements which could assure the customers that the devices are workable in the commercial LTE networks, customers pay more attention to the quality of services for different applications and the power consumption issues on devices.

In this project, we will proceed with the development of testing technologies and explore the research issues on the 4th generation broadband mobile system (i.e., LTE). The project consists of two parts, which are (1) basic testing (protocol conformance test and interoperability test) and (2) advanced testing (quality of service measurement and power saving verification). First, in addition to the conformance testing, we need to design the IOT test cases and analysis the testing results to shorten the development process for terminal devices. Next, in order to lengthen the battery life without violating the QoS, DRX parameters are introduced into the packet scheduling determinants when designing the scheduling algorithm. Finally, the accurate channel information (i.e., channel qualify indication, CQI) should be taken into consideration when designing the DRX scheduling and packet scheduling algorithm.

The contribution of this project is three-fold: 1) to fulfill the basic LTE testing requirements - test case analysis of protocol conformance test (PCT) and test case design of interoperability test (IOT); 2) to develop the testing platform for power saving mechanism and QoS/QoE measurement; and 3) to design VoIP QoS scheduling and channel-aware DRX scheduling algorithm. We plan to publish three papers, one patent and one IOT test case analysis report. PCT and IOT test case analysis reports are used as references for terminal devices development. The designs of QoS scheduling and DRX algorithm can improve the performance of the LTE system.