An Adaptive Relay Assignment and Power Allocation Algorithm in CRNs ⋆
نویسندگان
چکیده
In this paper, we present an adaptive relay assignment and power allocation algorithm in cognitive radio networks is proposed by using cooperative relay technologies which can improve the capacity of the cognitive system and extend coverage area. This algorithm converges faster than classic algorithms. The main target of the adaptive algorithm is to maximize each user’s capacity while guarantees SNR of the cognitive system. And this cognitive system will adaptive select best relay for participation in cooperative transmission. Therefore, power control problem can be formulated as a mixed-integer nonlinear programming problem solved under KKT conditions. Simulation results show that the proposed adaptive algorithm performs better and effectively compared with the classical ones.
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