WSN Design and Implementation in a Tea Plantation for Drought Monitoring

A Wireless sensor network (WSN) was designed and deployed in a tea plantation with the purpose of drought monitoring. The sensing nodes were designed, which are composed of an ATmega128L micro-processor, a CC2420 transmit-receive module etc. A WSN gateway layout scheme based on ARM was demonstrated. The networking experiments were conducted in laboratory with Mesh Routing Protocol to examine the network performance. Test results show that the performance of Quality of Service (QoS) declined with network scale extending from 5, 10, 15 to 20 nodes. Simultaneously, the topology formation time, the topology stabilization time and the topology reconstruction time got prolonged. The entrance of a new node did little effects on routing performance of a steady-going WSN. Diamond shaped node deployment was compared and adopted. Tests in tea plantation showed that the system is stable and packet Loss Rate (PLR) goes up when data transmission interval varied from 10s, 20s, 30s to 40s.