The Design And Implementation Of Cognitive Radio Communication System Based On GNU Radio

Traditional network applies invariable spectrum allocation policy and all nodes in the network work on a fixed single channel. In this case, not only the spectrum resources cannot be fully used, but also will block the communication between nodes and cause the failure of the link when the quality of the work channel degrades. The appearance of cognitive radio has been considered a direction to solve this problem. In the communication system which has applied the cognitive radio technique, the surrounding spectrum usage information can be obtained through spectrum sensing,and thus, the communication system can change its configuration parameters such as frequency and power adaptively so that the purpose of making full use of spectrum and making up for fixed allocation can be achieved. Meanwhile, the jamming channel can be avoided in data transmission because of the usage of spectrum sensing and channel management, so that the performance of data transmission can be improved significantly.This paper introduces a wireless data communication system based on GNU Radio and USRP software radio platform in which the key aspects of cognitive radio will be studied. Through interference-level detection, the system can perform channel management and thus, can avoid the channel interfered so as to improve the ability of data transmission. This paper studies the main function blocks involving in this system includes spectrum sensing, channel management,aggregation of work channel and data transmission and the implementation of it on GNU Radio and USRP. Through constructing the experimental platform and coding the program, the ability of data transmission of this system in the interference environment has been verified.