Cognitive Research Spectrum Sensing Wireless Network And Routing Algorithms

With the growth of wireless communication frequency resources demand increases increasingly, become very valuable. At the same time the frequency utilization rate is low:unfortunately some of the resources can not be fully used. As a reasonable solution to the problem of the reason, improve RF rare spectrum utilization, and proposed cognitive radio technology. To enable them to properly complete use of cognitive radio technology to make unauthorized wireless equipment actively find unoccupied unlicensed band, by properly choosing appropriate working frequency band and improves the spectrum utilization rate and avoid the interference and collision, so that to improve the communication efficiency. The research object is the key to cognitive radio networks, cognitive radio, this paper focuses on the study of cognitive wireless network this key problem.First, the research on cognitive radio, a very detailed introduction of cognitive radio. Summary of all current spectrum sensing scheme, cooperative frequency spectrum perception and cognition of routing algorithms in chromium is discussed, analyzed their advantages and disadvantages.In second, on top of the current spectrum sensing algorithm, spectrum sensing algorithm is a clustering algorithm, the method uses the user selects the diversity that the sensing performance to be improved. We employ an early gastric cancer of the soft combining scheme and hardware combination, improve the detection performance and reduce transmission costs. Compared with the traditional detection method, the numerical results show that the detection performance is improved markedly.Third, in view of the characteristics of the dynamic spectrum and the problem of intentional or unintentional backpack interference in cognitive radio networks, reasoning that a routing algorithm, the least hops, strong robustness and routing security level as routing criterion. The algorithm process, simulation results show that the algorithm can greatly reduce the potential transmission of conflict and interference, low delay, high throughput and stability than the route via the joint consideration of conflict and interference, the spectrum handoff delay and the number of hops.