為了因應全球氣候變遷，透過減少能耗來達到節能減碳的目標已成為全球關注的焦點。然而現今行動通訊設備所產生的二氧化碳含量，隨著使用行動通訊的人口數與資料量的持續攀升，造成能耗逐年上升進而危害環境，因此許多研究旨在發展具有降低能耗的通訊技術，即所謂的綠色通訊。設計出符合綠色通訊的行動通訊系統，而要求使用上具有高傳輸率、低能耗、易維護等特性，抑是近年的趨勢。本論文提出一個支援GSM微細胞服務之負載平衡節能接取網路架構，透過使用USRP軟體無線電設備來架設GSM微細胞基地台，利用射頻上載光纖技術來延伸基地台的無線訊號，並搭配負載平衡器實現低功耗的節能無線接取網路，可達成有效節能及易維護的需求。最後，利用負載平衡器節能運作方式，根據每日24小時通話流量負載圖的實際分析，實驗結果證明本架構可以在滿足使用者服務品質的前提下，有效節省整體網路約24%的能量消耗。

Energy consumption related carbon emissions being the main reason for the global climate change is becoming a major environmental issue. As the number of users of mobile radio networks keeps increasing along with the traffic load over these networks, their power consumption and the resulting released carbon products also keep rising. Designing communication systems that are green, capable of providing high data rate with minimum power consumption and easy to manage, becoming a global trend. Accordingly, a lot of research is being focused on power consumption reducing technologies, namely, green communications.

This thesis proposes a load-balanced green access network supporting GSM femtocell services structure. We utilized a software defined radio technology to establish SDR GSM femtocell (OpenBTS), using radio over fiber as the OpenBTS data transmission interface. The low complexity of load Balancedd green access network can have low complexity, low power consumption, and can meet the energy sewing needs. Finally, after using a loan balanced operation mode, based on 24-hour voice traffic average, we prove the energy saving of up to 24%.

[1] G. Fettweis and E. Zimmermann, “ICT energy consumption - Trends and challenges,” in Proc. of the 11th International Symposium on Wireless Personal Multimedia Communications (WPMC), 2008.
[2] B. Badic, T. O'Farrrell, P. Loskot, and J. He, “Energy efficient radio access architectures for green radio: Large versus small cell size deployment,” in Proc. IEEE Vehicular Technology Conference Fall (VTC-Fall), pp. 1-5, Sep. 2009.
[3] A. Fehske, F. Richter, and G. Fettweis, “Energy efficiency improvements through micro sites in cellular mobile radio networks,” in Proc. IEEE International Workshop on Global Telecommunications (GLOBECOM Workshops), pp. 1-5, Dec. 2009.
[4] 中國移動通信研究院, “C-RAN 無線接入網綠色演進,” March 2010. [Online]. Available: http://www.c-ran.com/portal.php?mod=view&aid=10
[5] E. Oh, B. Krishnamachari, X. Liu, and Z. Niu, “Toward dynamic energy-efficient operation of cellular network infrastructure,” IEEE Communications Magazine, vol. 49, no. 6, pp. 56-61, June 2011.
[6] Y. Chen, S. Zhang, S. Xu, and G. Li, “Fundamental trade-offs on green wireless networks,” IEEE Communications Magazine, vol. 49, no. 6, pp. 30-37, June 2011.
[7] W. Vereecken, W. Van Heddeghem, M. Deruyck, B. Puype, B. Lannoo, W. Joseph, D. Colle, L. Martens, and P. Demeester, “Power consumption in telecommunication networks: Overview and reduction strategies,” IEEE Communications Magazine, vol. 49, no. 6, pp. 62-69, June 2011.
[8] M. Marsan, L. Chiaraviglio, D. Ciullo, and M. Meo, “Optimal energy savings in cellular access networks,” in Proc. IEEE International Workshop on International Conference on Communications (ICC Workshops), pp. 1-5, June 2009.
[9] K. Samdanis, D. Kutscher, and M. Brunner, “Self-organized energy efficient cellular networks,” in Proc. IEEE International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC), pp. 1665-1670, Sept. 2010.
[10] 楊淳良, 光纖通信網路, 五南出版社, 2007.
[11] 樂孜純,光纖通信技術與系統光網絡上卷, 機械工業出版社, 2004.
[12] S. Lee, M. Chuang, C. Lee, C. Sun “Design and applications of radio-over-fiber Schemes to indoor wireless coverage and high-speed rails,” in Proc. IEEE 3rd International Conference Photonics (ICP), pp. 272-274 Oct. 2012.
[13] SDR Forum, [Online]. Available: www.sdrforum.org
[14] GNU Radio [Online]. Available: http://gnuradio.org/redmine/projects/gnuradio
[15] OpenBTS for dummies - v0. 2 Axelle Apvrille, Fortinet Inc., Nov. 2010.
[16] OpenBTS: Installation and Configuration Guide, May 2009. v0.1.
[17] OpenBTS [Online]. Available: http://gnuradio.org/redmine/projects/gnuradio/wiki/OpenBTSBackground
[18] A. Mohammed, “Studying media access and control protocols,” M.S. thesis, KTH Royal Institute of Technology, Stockholm, Sweden, Jan. 2010.
[19] Asterisk, [online]. Available: http://www.asterisk.org/applications/pbx
[20] Asterisk維基百科, [online]. Available: https://zh.wikipedia.org/zh-tw/Asterisk
[21] 國家通訊傳播委員會通傳營字第09841000240號令, “行動電話業務服務品質規範作業要點,” Jan 2009. [Online]. Available: http://www.ncc.gov.tw/Chinese/law_detail.aspx?site_content_sn=255&law_sn=743&sn_f=1435&is_history=0
[22] D. D. Kouvatsos, K. Al-Begain, and I. Awan, “A queueing model for a wireless GSM/GPRS cell with multiple service classes,” in Proc. the 2nd International IFIP-TC6 Networking Conference on Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; and Mobile and Wireless Communications, pp. 984–995, 2002.
[23] S Theodore., “Wireless communications: Principles and practice,” in Plastics, 2nd ed. Prentice Hall Communications Engineering and Emerging Technologies Series, 1999.
[24] J. Boucher, “Traffic system design handbook: Timesaving telecommunication traffic tables and programs,” in Wiley-IEEE Press, 1993, pp. 33 - 78.
[25] A400P on DAHDI User Manual, 2nd ed., OpenVox Communication Co. Ltd.
[26] 佐臻股份有限公司, “EZCom 評估套件操作手冊,” Aug 2011. [Online]. Available: http://ezcom.freeforumfree.com/f3-forum
[27] PROVA-8500電力節能測試儀, [online]. Available: http://www.tes.com.tw/8500c.htm
[28] M. A. Imran and Project Partners, “Energy efficiency analysis of the reference systems, areas of improvements and target breakdown,” EARTH project, Tech. Rep., Dec. 2010.
[29] C. Forster, I. Dickie, G. Maile, H. Smith, and M. Crisp, “Understanding the environmental impact of communication systems - final report,”Gary Clemo Ofcom., Rep. GGR007, Apr. 2009, vol. 3.