The Research Of Adaptive Selection Algorithm About Relay Node Based On Cooperative Communication

In wireless communications, cooperative communication technology can effectively overcome multipath fading, which has been the focus of attention of researchers around the world. The cooperative communication relay node selection algorithm has a great influence on the transmission performance of cooperative communication systems. Therefore, researching on the cooperative communication relay node selection algorithm will be very meaningful. The main work of this paper studies is done as follows.First of all, The amplify and forward and the decode and forward are derived. Based on rayleigh fading channel simulation an average error rate of two forwarding tactics forward is gotten. Through analysis, the following conclusions can be gotten. If the signal to noise ratio of the channel is relatively high, The AF can be used for forwarding. If the signal to noise ratio of the channel is relatively low, The DF can be used for forwarding.Secondly, The research status on the relay node selection algorithm is analyzed, and a classify the discussion is gotten for the algorithm, comparing their advantages and disadvantages. It is focused on the algorithm of relay node selection based on the instantaneous relay node channel state. Relatively fixed position of the relay note, the source note and destination node are in the existing premise relay selection algorithm implementation. If the change of position of the relay node isn’t considered when the system is adaptive selection artificially set threshold is needed to. Leading a result of the system is not high in intelligence. In order to improve the practicality and intelligent cooperative communication, An improved relay node selection algorithm. Is proposed. Which can be based on the positional relationship between the relay node and the source node and the destination node, an adaptive threshold is set, the relay node selection based on this threshold synergistic strategy. Subsequently, based on Rayleigh fading channel and Rice fading channel my existing algorithms and a new algorithm for the simulation. Which proved the improved algorithm with respect to the existing algorithm, not only to improve the signal transmission quality, but also improve the intelligence of the system, it has some practical value.