Cognitive Radio Spectrum Allocation Problem In Relay-based Research

With the rising demand for wireless communication, more and more people demand for wireless spectrum resources. The contradiction between the static spectrum allocation strategy and the rising demand for wireless communication has become increasingly prominent. Cognitive radio as smart radio, flexible, intelligent, reconfiguration of the salient features of her environment, and use artificial intelligence techniques to learn from the environment, destination, real-time change certain operating parameters, so that the internal state to adapt to the statistical variations of the received wireless signal, in order to achieve any time, any place of the highly reliable communication and efficient use of the limited radio spectrum resources of the heterogeneous network environment, i.e. Cognitive radio is a very effective technique to ease the current strain on the resources of the wireless spectrum. In this paper, we focused on the following:1. In cognitive radio relay network, we study the different relay mode power constrained optimization allocation scheme. And with the convex function optimization theory and Lagrange multiplier method, we obtain the optimal solution for power distribution.2. We investigate power and channel allocation for cooperative relay in a three-node cognitive radio network. The algorithm takes full advantage of the three wireless cognitive relay network transmission mode (direct transmission, dual-hop transmission and relay of the diversity transmission), each available frequency band assigned to one of three types of transmission, and on this basis on the distribution of power, Finally, we compare the system performance under each assigned to select the optimal allocation. Simulation analysis data, the algorithm is compared to the traditional single-channel power allocation, the performance is greatly improved.