Frequency Spectrum Assignment Technology Based On Model In Cognition Radio

With the application of wireless communication technology in the areas of society, the radio spectrum resource has become the one of the most important resource in modern society. At the same time, the contradiction between the scarcity of spectrum resources and its low average utilization rate become more and more prominent. By perception of the surrounding environment, cognitive radio technologies detect available spectrum resources, then improve the system spectral efficiency effectively. Cognitive radio spectrum allocation technology is the key technology of cognitive systems, through the rational allocation, which has used the frequency spectrum resources effectively, and has play a key role in the improving of the performance of cognitive radio systems.This paper mainly studies on the spectrum models of cognitive radio system. Firstly, center-type model was analyzed and researched. Secondly, several classical allocation algorithms were summarized and analyzed. In view of the existing algorithm's insufficiency, this paper proposes a dynamic frequency allocation algorithm based on sub-channel division. At last, several algorithms were analyzed in aspects from the system's expenses time, effectiveness and fairness. The algorithm's practicality was summarized.In order to solve the shortcoming of the cognitive radio interference temperature model, a dynamic spectrum allocation program base on MIMO-OFDM was proposed. This program improves the interference temperature model, cognitive signal adaptive frequency spectrum formation realization. A new dynamic power allocation algorithm was proposed. Simulation results show that this program can overcome local interference problems of the interference temperature model. The use of MIMO technology can further improve system performance. And it can reduce computational complexity and improve spectral efficiency through dynamic power allocation algorithm.