Cognitive radio-based multi-relay selection method

Abstract

The present invention discloses a cognitive radio-based multi-relay selection method. According to the method of the invention, required information is collected and initialized by a cognitive source node, and the transmitting power of a current relay node is determined; the source node first calculates total interference under a current relay node set, determines whether the total interference exceeds an interference threshold, and calculates the transmission factors of corresponding relay nodes if the total interference does not exceed the interference threshold; a relay node with the largest transmission factor is selected as a cooperative relay; and the source node performs relay node selection and power control according to the criterion of channel capacity maximization, and gradually reduces the power of the relay nodes until assumed relay power is reduced to zero. According to the method of the invention, when the relay node selection is carried out, the transmission factors are adopted as a selection criterion, and therefore, interference on a main user caused by cognitive relay nodes is fully considered, and the channel capacity of a system can be effectively improved; and a quantitative grading method is adopted to perform power control, and therefore, the complexity of the implementation of the method can be decreased.

Description

technical field [0001] The invention relates to a relay selection method in a cognitive relay network, belonging to the technical field of wireless communication. Background technique [0002] With the popularity of smart phones and the development of short-distance transmission technologies such as wireless local area network technology and wireless personal area network technology, more and more people access the Internet wirelessly through these technologies. However, the reason why these technologies can provide people with free and convenient broadband access is that most of them work in unlicensed frequency bands that do not need to be purchased. Compared with the licensed frequency bands, most of these unlicensed frequency bands were originally planned by the government for amateur users who do not need a large amount of frequency band resources. Spectrum usage is very low. According to a survey by the Federal Communications Commission of the United States, the over...

AI Technical Summary

Problems solved by technology

At the same time, in order to solve the problem that the interference caused by the relay node is not fully considered in the existing methods, a heuristic relay selection method based on the relay factor is proposed, and combined with the above power allocation method to form this A multi-relay selection method based on cognitive radio described in the invention

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