Design of a WSN Node for Rice Field based on Hybrid Antenna

Aim at the problems existing in the information monitoring of the farmland environment such as the limited energy, low system stability and large monitoring area, a WSN node for rice field based on hybrid antenna is designed to realize the real-time on-line monitoring for the environmental parameters of rice fields in the network. As for the hardware, the node uses a STM32F103VET6 as a processing core, and a WLK01L39 RF chip is used in wireless communication module, while the sensor module is composed of the air temperature and humidity sensor, light intensity sensor and soil moisture sensor. As for the software, uC/OS-II is applied as an operational system to realize multitask scheduling running. The sensor node applies a mechanism as sleeping and waking up work modes to reduce power consumption. The current consumption of sensor nodes is 0.024mA under the sleeping mode, 32.32mA under the data collection, 26.25mA under data transmission and 21.95mA under the operating mode. The results of a long time networking experiment indicate that the average PLR (Packet Loss Rate) of network is 0.76%. In conclusion, the design of sensor node system is suitable for the real-time and stable monitoring of rice field.