中文摘要：

针对现阶段果园无线节水灌溉系统成本高、传感器节点寿命有限、不能长期可靠工作等问题,介绍了一种基于无线传感器网络节点的果园自动灌溉系统设计方案。该系统由主节点、传感器节点、水泵节点3种节点组成,通过选取合适功率的太阳能电池板和太阳能电池充电芯片对锂电池进行充电,有效延长了传感器节点寿命,实现系统连续稳定工作。在空旷地带,系统的有效通信距离208 m,节点额定电压5 V,工作时电流125 m A,待机时电流1.6 m A,太阳能平均充电电流为20 m A。传感器节点在不充电的情况下,以每天唤醒24次,每次工作20 s的频率,可连续工作约60 d。在连接太阳能电池板的情况下,可保证充电电量大于耗电电量。在桃园的试验表明：传感器节点在采集土壤湿度信息时耗电量最大,连接太阳能电池板,电池电压在额定电压附近小范围内波动,随机改变灌区内被测土壤湿度,系统可以按照设定的土壤湿度上限、下限,自主控制水泵和电池阀工作状态,实现自动按需灌溉。

英文摘要：

To solve the problems like high cost of water-saving irrigation system, limited lifetime of wireless sensor node, no long-term reliable operation and other issues for orchard irrigation, this paper introduced a orchard automatic irrigation system design based on wireless sensor network node. The system consists of a master node, sensor node and pump nodes. By selecting the appropriate power, solar panels and solar battery charging chip of lithium rechargeable batteries, the system effectively extends the life of the sensor nodes to achieve continuous system stability. In an open area, the effective communication distance is 208 m, node rated voltage is 5 V, operating current is 125 mA, standby current is 1.6 mA, and solar average charging current is 20 mA. Without charge, for waking up 24 times a day with frequency of 20 s, sensor nodes can work for about 60 d. In the case of connecting solar panels, rechargeable battery ensures more than power consumption. Test in orchard shows that, the sensor nodes consume the maximum power for the collection of soil moisture information. Under the condition of connected solar panel, battery voltage fluctuates within a small range of rated voltage. Randomly changing the soil moisture of irrigation area, the system can autonomously control the working status of pumps and valves battery according to the automatic irrigation demand. upper and lower limits of soil moisture, to meet the