A path loss exponent based localization algorithm in cognitive radio networks

In cognitive radio networks, acquirement of the position information of primary user (PU) is of vital of importance to the communication of the secondary users(SU), as it can be used to avoid harmful interference to the network while simultaneity be exploited to improve the spectrum utilization. In this paper, a localization algorithm based on RSS (Received Signal Strength) is proposed to solve the secondary users´ problem of locating the primary users in CRN (Cognitive Radio Network). To improve the precision, a method to estimate the path loss exponent in the primary users´ region using the secondary users´ information nearby is proposed. The path loss exponent is determined by the secondary users´ communication. Simulation shows that the exact measurement for the path loss exponent can promote the localization precision obviously.