Campus greenhouse monitoring with a simple ZigBee-based sensor network

The concept of greenhouse is to create a controllable environment suitable for vegetation growth. By stabilizing environmental parameters including lighting, temperature, humidity, and soil moisture, the yield of vegetable and fruit can be effectively increased. Commonly, greenhouse is a non-open space and lighted with solar-like sources. The light source will emit infrared ray that can heat the room and cause loss water in soil. Automatically monitoring the parameters can not only save man power but also facilitate growing environment control. ZigBee with low cost, low power and long communication distance is an efficient wireless communication device widely used in home-network. In this paper, a simple ZigBee-based sensor network is proposed for the campus greenhouse monitoring with mobile device. The system consists of three modules, a mesh structure network, data processing center, and mobile application program (APP). The network involves three functional nodes and is responsible for sensed data delivering. These nodes are modularly designed. Considering self-healing, a simple network operation system that applies `token', data flow, and, hand shaking techniques.is also built. There are three functions for the data processing center. The first is filtering received data and saving correct data in a database, the second is data analysis and control action, and the third serves the requests of mobile device. APP installed in mobile device is a simple function that enables remote monitoring for sensor status and environment parameters. The framework has been implemented for performance evaluation. The experimental results validate the feasibility of the new ZigBee-based transducer structure.