Research On Dynamic Channel Allocation Algorithms In TD-SCDNA System

TD-SCDMA, the third generation mobile communication standard that China puts forward andholds the independent intellectual property rights, is one of the four primary standards certificated byITU. It adopts smart antenna, joint detection and synchronous CDMA and other advancedtechnologies which gives the system higher performance and frequency utilization efficiency.We thoroughly analyze and deeply research on the Dynamic Channel Allocation Algorithmwhich used in TD-SCDMA system. and the main contribution is shown as follow:Firstly, the mainstream technology of the Dynamic Channel Allocation Algorithm is introduced,then four typical DCA algorithms are analyzed, and the advantages and disadvantages of thesemethods are pointed out.Secondly, a system level simulation model for TD-SCDMA is built. According to the diversity,several significant parameters of DCA algorithm is analyzed in detail, all of those lays the foundationfor the research model, the algorithm analysis and simulation experiment of the full text.Thirdly, the minimum interference DCA algorithms are improved. Based on the principle ofminimum interference, inter-cell interference is analyzed. Combining cell dividing method with timeslot dividing method, we improve the algorithm.Finally, a DCA algorithm based on cognitive radio has been proposed. The Dynamic ChannelAllocation, that uses the Cognitive Radio technique, can investigate radio spectrum resources, learnintelligently and adjust system parameters real-time with free spectrum adaptive algorithm. Throughthe intelligent decision-making and effective distribution strategies, free spectrum is assigned to thecognitive users.In short, the new DCA algorithm based on minimum interference criterion makes interferencereduce and capacity enhance. The DCA algorithm, which is based on cognitive radio, makes thecall-blocking rate and data substitution rates has been reduced, and reaches to a larger system capacity.Therefore, the two DCA algorithms presented in this paper are effective to improve the systemperformance and have a strong theoretical significance and application value.