Modeling Wireless Propagation in Rice Crops

In the field of precision agriculture, the models and characteristics of wireless channels are a valuable resource to ensure that a sensor network has good communication. An experiment was carried out to transmit a wireless signal through a rice crop by varying the distance between antennas and their height, at the tillering, internode elongation and grain production stages. The attenuation variation for different transmission distances was compared and the comparison between estimated and measured RSSI values based on different propagation models was analyzed. A regression analysis was used to fit the conventional free-space and two-beam models to the studied channel, determine a log-distance model and propose a fitted two-beam model.