Energy efficient localization of primary users for avoiding interference in cognitive networks

Cognitive Network is an intelligent network that is aware of its surrounding environment, and adapts the transmission or reception parameters of either a network or a wireless node to achieve efficient communication without interfering with primary users. For avoiding interference to primary users, cognitive users must be aware of primary users within the region of interest and disable themselves whenever primary user is active. However, it is not possible to identify the location of the passive listening primary users, and causes hidden node problem in cognitive networks. This paper applies leveling and sectoring based approach for localization, and then disable region is identified considering the communication range of both primary and cognitive user. This will avoid the interference caused by hidden node problem. The cognitive users within the disabled region are sent to sleep mode until a free channel is detected in that area by spectrum sensing module. This approach avoids interference with primary user and also saves energy of cognitive users. As this approach conserve energy of cognitive users as well as simple to implement, it is suitable for CWSN.