Energy Detection Based Periodic Dynamic Spectrum Sensing Using Cognitive Radio
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering
In today's world, with rapidly growing mobile data traffic, our primary objective is to build a smart wireless communication system that is cognizant of its surroundings and adjusts statistical parameters of its input in order to best utilize the spectrum. Cognitive Radio offers a solution to spectrum scarcity by utilizing the spectrum holes. In this paper, I have considered a network operating in a decentralized cooperative manner. Thus, informationbearing signals can hop from one node of the
... om one node of the network to a neighbouring node, thereby facilitating communication across the entire spectrum. Here periodic dynamic spectrum-sensing using energy detection method is proposed because of its low computational and implementation complexity. In the proposed method the whole spectrum range is divided among five licensed or primary users. Whenever a slot is empty, a secondary user is assigned that slot. So, at most total five numbers of secondary user can be accommodated. The spectrum is sensed periodically. After some time period when primary user is activated in that slot, the secondary user is automatically transferred to another vacant slot or if vacant slot is not available, it is deactivated. The simulation is done in MATLAB platform. And the simulated result shows that cognitive radio users can sense the whole spectrum periodically and allocate its spectrum dynamically among the secondary users. Fig 8: reallocation of secondary user spectrum V.CONCLUSION I have studied dynamic spectrum sensing using energy detection based method in cognitive radios. Here the whole spectrum is periodically sensed and the vacant slot is allocated to secondary user instantly. If primary user in that vacant slot becomes active again, the secondary user is deactivated immediately and reallocated to other vacant slot if it is available. If no slot is vacant secondary user is deactivated.