LTE多階層行動網路中的節能機制

Abstract

近年來，環保問題已經引起全球的注目與關心，其中，資通訊產業所造成的二氧化碳排放量變得越來越重要，主要原因之一是數量暴增的智慧型行動裝置，進而造成基地台更多的用電支出以及能量消耗。 在LTE無線網路中，涵蓋率是個重要的議題。毫微微基地台是一種可經由寬頻網路佈建的低功耗無線存取點；它不僅可解決室內涵蓋率問題，還能夠協助解決大型基地台的流量暴增問題，因而被廣泛採用。許多文獻更指出，無線網路架構中，絕大部分的能源消耗是來自於大型基地台的耗電，原因是為了應付龐大的無線網路流量，且該現象變得越來越嚴重，因此，在未來的資通訊產業中，重視節能省電是個非常重要的課題。因此可以認定未來包括毫微微基地台的多階層無線行動網路架構中，將會是如何降低整體基地台的能量消耗之關鍵所在。 在本論文中，發展一個以毫微微基地台為主的節能通訊蓋念，有關於如何更有效配置資源區塊，以及決定開關哪些毫微微基地台的機制。除此之外，本論文也探討當一台典型的毫微微基地台能夠服務多個使用者時，能夠帶來怎樣的節能效益。這套節能的概念能夠降低約22%的總能量消耗，以及約70%的額外能量消耗。

These days, environmental concerns have caught public’s attentions worldwide. The issue about Carbon emission of the ICT industry also becomes more and more important. One of the reasons is the growth of operation cost coming from electricity consumptions due to the increasing use of mobile devices. In LTE wireless network, coverage is also a big issue. As a result, femtocell access points, which are low power wireless access nodes connecting to the core network using broadband digital subscriber line connections, have been widely used to solve indoor coverage and the network overload problem. Many literatures has pointed out that most of the energy consumption of current wireless communication network architecture is due to the contribution of base stations. The situation is becoming worse as more and more base stations are deployed to deal with huge wireless traffic growth. It is thus crucial to reduce the energy consumption of base stations for evolution toward the green information and communication technology in the near future. We believe a two tier macro-femtocell network should be the key network architecture to reduce the total energy consumption of these base stations. In this thesis, we develop a green concept about how to allocate the resource block more efficiently, and how to decide which femtocells to be turned on. Besides, we discuss the impact of a femtocell when it serves more than one mobile user. The proposed green-concept network design can reduce about 22% power consumption or 70% extra power consumption.