Design And Implementation Of Simulation Platform For WRAN System Based On IEEE 802.22

With the fast growing of wireless communication,the spectrum resources have become scarce.We are forced to adopting cutting edge communication technology to improve the spectrum utilization,at the same time,we recognize that a great deal of spectrum,especially the low frequency with good propogation characteristic,have low overall duty cycles.Therefor,at present reuse the licensed vacant frenqency have become a hot topic.Cognitive radio technology as a smart spectrum-sharing technologies to be effective in alleviating the low spectrum utilization, through sensing frequency domain,time domain and space domain such as space environment,automatically search and occupy free licensed spectrum,to address a new way on how to improve spectrum utilization of the wireless communication problems created in the limited spectrum resource conditions.The IEEE 802.22 Working Group is founded in November 2004.The purpose of the IEEE 802.22 Working Group is to develop a standard for the wireless regional area network(WRAN) based on cognitive radio technology.Although there is consensus over the overall goals and features of WRAN technology,many related and specific concepts remain underdeveloped.As a result,a rational system level simulation platform is critical for investigating WRAN system level issues and for validating our solutions.This paper firstly introduces the cognitive radio technology and gives brief explainations of the key technical parts of cognitive radio, followed by the summarizing of the relating standard organizations' research status towards the cognitive radio. Then the paper introduces the broadband wireless access and WRAN technology,analyzes the system architecture and PHY/MAC protocol of WRAN system based on IEEE 802.22,and also briefly describes the aims and methods of WRAN system simulation.The paper then focuses on the overall design and the specific modules design of WRAN system level simulation platform,gives clear explainations of the design methods,including the key technologies and algorithms.Finally,the realization of WRAN system level simulation platform is introduced.The paper gives detailed procedures of every module and lastly shows some simulation results to demonstrate the performance of the system simulation.