Feasibility of RF energy harvesting for wireless gas sensor nodes

Wireless Sensor Network (WSN) paradigm has been applied to a high number of monitoring and control applications. However, the scarcity of WSN energy resources imposes restrictions on its truly ubiquitous and long-term deployments. We address the problem of long-term autonomous operation of a wireless gas sensor by employing the far-field RF energy harvesting technology at 900 MHz in the power range from −20 dBm to 10 dBm. The node conducts regular CH4 or CO measurements and communicates the data to a wireless network coordinator at 2.4 GHz. Experimental results demonstrate that the optimized energy consumption of WSN, as well as energy harvesting of at least 1 mW (0 dBm) from ambient RF signal, ensure the 'perpetual' operation of WSN.