Design And Implementation Of Improved Radio Frequency Calibration Scheme Based On The Centralized WLAN Network

Enterprise applications which increasingly deployed in mobile terminal appeared due to the explosive growth of the mobile terminal.Meanwhile,more and more critical enterprise applications were transferred to WLAN network,resulting in more complex wireless access point(AP)topology and radio frequency management.Thus,the basic radio frequency calibrate scheme of centralized WLAN were proposed by the practice enterprises.However,it seems difficult to effectively adjust channel and power of APs and then reduce the interference with each other through using the scheme.To solve this problem,this thesis is supposed to investigate and improve the basic centralized WLAN radio frequency calibrate scheme,making it quickly adapt to changes in wireless network environment,thereby ensuring the good communication quality.The thesis is organized as follows:(1)The basic radio frequency calibration scheme of centralized WLAN proposed by the practice enterprise are investigated.The key algorithm processes of channel allocation and power control are analyzed in details respectively.Moreover,the problems existing in the two algorithms are summarized.(2)The improved algorithm of dynamic channel allocation is designed in terms of the problems of the unreasonable assignments of AP's channel induced by the basic radio frequency calibration scheme of centralized WLAN.It deals with serious interference AP in priority,adds the calibrate evaluation group into the interference calculation,and compares the magnitudes of integrated interference based on different network environment,respectively.(3)The improved algorithm of transmit power control is designed in terms of the dynamically unadjustable problems on AP's power induced by the basic radio frequency calibration scheme of centralized WLAN.It combines power control with blind and countervailing blind strategy to adjust transmit configuration of AP dynamically.(4)The implementing and testing are conducted based on the improved radio frequency calibration scheme,and the testing results are then analyzed.The results show that this improved scheme can not only effectively achieve the best channel distribution for AP,reducing co-channel interference between APs and improving the ability of anti interference for AP in high density network environment,but also adjust transmit power of' AP dynamically,ensuring full signal coverage without radio frequency interference between APs.This improved scheme has been well applied in wireless network deployments of the enterprises.Application results indicate that the improved scheme can effectively allocate reasonable AP distribution channel and power in the wireless network of the enterprises,thus reducing the interference between the APs.