Evaluation of Energy Efficiency of IEEE 802.15.4 CR-WSN under Interfered Environment

Recent rapid growth in low-power wireless technologies has increased the number of devices sharing the popular unlicensed 2.4 GHz Industrial, Scientific and Medical (ISM) spectrum. Incompatible communication pattern of these multiple heterogeneous networks in diverse applications, like Wireless Sensor Networks (WSN), Internet of Things (IoT) and individual wireless communication, could cause severe radio transmission co-existence issues, service performance and power consumption. As mobile networks are usually battery-powered devices, energy efficiency (EE) of sensor nodes is interesting both theoretically and practically. The main challenge is to reduce the energy consumption of motes so as to improve and extend the entire network lifetime. In this paper, we undertake an experimental study in achieving the optimization of energy consumption of IEEE 802.15.4 enabled nodes by using cognitive radio (CR) capabilities under an interfered indoor office environment. The implementation is done using Tmote sensors, GNU Radio and Universal Software-Radio Peripheral (USRP) platform. The Packet Reception Rate (PRR), Throughput and Energy Efficiency (EE) are measured for this system. The results show that CR function significantly impacts the whole power consumed while maintaining required performance of transmission links.