Results of Wireless Sensor Network Transceiver Testing for Agricultural Applications

Abstract

Radio frequency propagation for wireless sensor networks in agricultural environments faces challenges due to placement of nodes for wide-area mesh coverage and reliable link quality above crop canopies. Environmental conditions may also have a role in receiver signal strengths. IEEE 802.15.4/ZigBee XBee Pro 2.4GHz wireless sensor network devices were tested to determine distance and height limitations on signal strength. Testing of signal strength and link quality was performed to simulate effects of changing crop canopy heights. Data indicated attenuation and signal strength variance were dependent on line of sight (LOS) losses and heights less than the Fresnel zone radius. Testing of receiver signal strength during heavy precipitation indicated non-uniform losses and variance in signal strength across available frequency channels.