Cooperative spectrum sensing for mobile users

Cognitive radio is a radio communication technique, where unlicensed or cognitive users monitor the spectrum for the existence of licensed (primary) users and have a communication capability when the primary users donpsilat transmit their data. This technique needs an effective spectrum sensing because of the not disturbing the primary users. The increasing of this effectiveness is related with the higher detection probability of the existing primary users. In this paper, new cooperative spectrum sensing technique recommended for mobile users when the environment is free space line of sight (LOS). It is confirmed with this technique that the probability of detection of the primary userpsilas existence increases with the using of cooperative diversity by mobile users. It is resulted that this increasing of the detection probability is well-proportioned with relay numbers who helps target secondary user. In addition to this, systempsilas performance increases with the threshold distance of the true sensing. But it is demonstrated with the detailed simulations that the probability of detection of the primary userpsilas existence decreases with the speed of the mobile users.