Design of wireless sensor node for drought monitoring in tea plantation

For the application of tea drought monitoring, a wireless sensor network (WSN) sensing node was designed which is suitable for setting up a WSN in tea plantation. Each of the sensing nodes was composed of an ATmegal28L micro-processor for data processing and controlling, SHT11 and TDR-3 sensor modules for data measurements, and a nRF905 transceiver module for data transmission and reception. In-field networking experiments were conducted in 5 different node deployments based on nodes density. The average values of packet loss rate (PLR) under different scenarios were 0.96%, 3.47%, 7.86%, 10.65%, 14.83%, respectively. Results indicated that the system can collect the temperature, humidity and soil water content, and transmit data remotely to the base station, provided with the characteristics of working stability and reliability.