2.4 GHz RF Received Signal Strength Based Node Separation in WSN Monitoring Infrastructure for Millet and Rice Vegetation

The WSN monitoring infrastructure developed for a vegetative environment may encounter network disconnectivity due to node isolation if the node deployment strategy has not accounted for the change in vegetation density at different crop development stages. This proposal develops a path loss model by analyzing the effects of vegetation height and density on signal strength between two sensor nodes communicating under the IEEE802.15.4 Wireless standard. For this, the path loss coefficients have been analyzed for 2.4 GHz RF signals through measurement campaigns at various development stages of Rice and Millet crop. The proposed path loss model controls the separation between sensor nodes to achieve a distribution that is resistant to network disconnectivity caused by node isolation. The acquired database and formulated path loss model can be used by IoT network architects and researchers in the field of precision agriculture as a benchmark for network development and comparison with the signal strength in other crops.