Optimal power control for cognitive radio in spectrum distribution using ANFIS

Cognitive radio is an intelligent software-defined radio that solves the matter of spectrum shortage. In case of spectrum sharing network, one of the targets is to obtain balance between two contradictory goals that are to progress the performance of the secondary user and to decrease the interference to the primary users. In our paper we consider a primary and a secondary or cognitive link in a fading channel of with path loss propagation environment in a wireless network. To progress the performance of the secondary user by sustaining the good Quality of Service (QoS) to the primary user, we decide to vary the transmit power of the secondary user. For this we plan opportunistic power control strategy based on ANFIS model with primary user´s SNR and relative distance between primary and secondary user as inputs. By using fuzzy inference system, QoS of primary user is maintained. The improved performance is achieved from simulation results.