Research On Energy Saving Technologies Of EPON And WiMAX Hybird Access Network

Nowadays the world initiates low carbon, environmental protection, green and sustainabledevelopment."Energy-Saving and Emission Reduction" is the constant theme. According tostatistics, information and communication technology（ICT）energy consumption accounts for about8%of the entire world power consumption, then every year to10%of the rapid growth of energyconsumption. As "the last mile", access network energy consumption accounts for about70%oftotal energy consumption in ICT. Because of the huge energy consumption in access network, iturgently needs to save energy and reduce emission.Ethernet passive optical network（EPON）in the access networks provides users with reliable,high bandwidth, low bit error rate of the service. But the high cost of fiber deployment and lowflexibility become its disadvantages; Worldwide Interoperability for Microwave Access（WiMAX）has the advantages of low deployment cost, flexibility and high mobility. However, it has lowbandwidth, limited spectrum and low transmission rate. The two technologies constitutecomplementary advantages and account for a large proportion in the access network. Henceintegration of EPON and WiMAX is an inevitable trend. As designed unreasonably, the hybridnetwork has high power consumption and low utilization rate of equipments. Therefore, designinglow energy consumption network has become one of the key problems to be solved by nowadayscientists.This article from the perspective of energy saving and emission reduction in EPON andWiMAX hybrid access network namely Fiber-Wireless （FiWi） access network, with ensuringnetwork performance, researches on energy saving technologies of the whole network, includingnetwork architecture and algorithm about energy-saving. Research work is as follows:（1）Research on three integration architectures and fusion mechanisms of EPON and WiMAX,including baseband fiber transmission, Radio Over Fiber (ROF) and Microwave Over Fiber (MOF).And do comparative analysis about the three integration architectures.（2）Study on the energy-saving mechanism of EPON and WiMAX respectively; design a greenFiWi integrated access network scheme and elaborate the scheme. Compared with the threemethods mentioned above, research shows that the proposed scheme has a lower energyconsumption.（3）Apply EPON energy-saving algorithm to FiWi, two FiWi energy-saving algorithms have been achieved: Energy-saving Algorithm based on Variable Guard Slot（EAVGS）and Dynamicenergy-saving Algorithm based on Variable Guard Slot（DAVGS）. To reduce the energyconsumption of the whole network, the guard slot is adjusted dynamically according to the twodifferent algorithms under the network delay requirement. The proposed two algorithms aresimulated by MATLAB. The simulation results demonstrate that the two algorithms have notableenergy saving effect. Since DAVGS is not affected by the traffic load effect, it has better energysaving effect and more stable performance than EAVGS.