The Study Of The Coexistence Of WCDMA And WiMAX System

The development of both wired and wireless networks will lead to the convergence of telecommunication and data networks which is based on All-IP connection. Meanwhile, the competition between various broadband wireless access technologies, e.g. 3gpp and WiMAX, is becoming more and more severe. As we know, the radio spectrum is essentially important for the development and commercialization of the wireless technologies. Therefore, the study of harmonious coexistence between two different technologies in the adjacent frequency or even in the same frequency becomes a meaningful and challenging task for the researchers.WiMAX has been successfully approved by ITU as a part of 3G standard in Oct. 2007, which means WiMAX is more likely to use the radio frequency assigned to 3G in the future, In China, 2.5G and 3.5G are the potential spectrum for WiMAX; however, 3.5G is already assigned to satellite communications and 2.5G is also reserved for 3G technology such as WCDMA, CDMA2000 and TD-SCDMA. Therefore, the simulation of coexistence between WCDMA and WiMAX system is an important reference for the assignment of radio resource.The thesis mainly focuses on the study of the coexistence of WiMAX and WCDMA system in adjacent frequency at 2.5G The simulations use Monte Carlo statistic method in the macro-cell scenario, and get the proper ACIR value which decreases the interference between two systems to a tolerable value. The uplink power control algorithm of WiMAX system is also analyzed to evaluate the impact of power control to the WCDMA and WiMAX system when they are coexisting.Two results are obtained from the simulation. One is that the interference between WCDMA BS and WiMAX BS is highest when the distance between them is zero. Therefore, we need the highest ACIR to reduce the interference. The other is that the uplink power control in WiMAX system is helpful to reduce the interference to both the WiMAX BS and the WCDMA BS. Meanwhile, when the number of users in the sector of WiMAX increases, the interference to WCDMA system will also increase accordingly. Therefore, the requiring ACIR value should also been increased.The simulation results can be a great reference to the deployment and commercialization of WCDMA and WiMAX system in real environment.