Broadband Wireless Metropolitan Area Network Real-time Communication Systems, Power Control Technology Research And Implementation

In recent years, along with the popularization of the Internet, the network servicehas penetrated into every aspect of people's lives and the network becomes anindispensable part of people's daily lives. Now the network is converting to a wirelessand Internet-protocol-based(IP-based) network and it is the inevitable direction of thedevelopment of the network. The Internet Engineering Task Force(IETF) hasconstituted different sets of standards to surport different market needs in the wirelessfield, including the standards of the IEEE802.15 which is applied to the wirelesspersonal area network(WPAN), the IEEE802.11 which is applied to the wireless localarea network(WLAN), the IEEE802.16 which is applied to wireless metropolitannetwork(WMAN) and so on. As it is presented currently, the WMAN standard(IEEE802.16) becomes one of the hottest wireless networking technology becuase of itsbroad bandwidth, low cost and other merits.In order to reduce the co-channel interferences of the OFDM wireless system sothat we can increase the capacity of the system, we can adopt power control technologyin the WMAN communitation system. This dissertation mainly focuses on reporting myresearches on the problem area relating to the power controlling in the WMAN realtimecommunication system. The main contents of my researches are generalized below:Firstly, the dissertation briefly introduces the evolution of the power controltechnology. Based on these, it analyses several classical power control algorithms andsummarizes the merits and demerits of them. After this, the power control algorithm ofIEEE802.16 is also introduced and analyzed. This dissertation points out itsshortcomings, which will be the problems to be solved. Additionally, it introduces thesoftware system of the realization of the IEEE802.16e MAC as well as the hardwaresystem, which is implemented by the picoChip company, to support the PHY of thatspecification.Secondly, aimed at the emphasis on the research work, this dissertation alsopresents four implementing schemes of the power controlling algorithms in the WMANcommunication system: the uplink open loop power control scheme, the uplink closed loop power control, the uplink open loop and closed loop combined power controlscheme and the uplink and downlink combined power control scheme. Based on thecomparison on the four schemes, it obtains an optimized scheme to implement thepower control algorithms in the WMAN communication system. Then I implement thescheme under Linux OS as a part of the network driver with all the functions of thepower control module of the base station and the mobile station.Finnally, we build a test bed of WMAN communication system, which is basedon the IEEE802.16e specification. The power control algorithm is applied to it. We testthe performance of power control algorithm on the test bed. The testing result showsthat the proposed power control scheme in this dissertation is validated and feasible.