Wireless monitoring of the pH, NH4+ and temperature in a fish farm

Abstract In this paper, we present a practical application for wireless sensor networks (WSN): The sensing of the pH, NH 4 + and temperature for a fish farm. Two different kinds of modules were designed: Te sensor and the wireless module. The sensor module includes pH and NH 4 + sensors based on a specially designed ISFET. The sensor module collects and transmits the information to the wireless module by means of a 9600 b/s asynchronous wired communication. The wireless node, retransmit it to the central unit via RF. The WSN follows the standard IEEE 802.15.4 and implements a routing protocol based on Zigbee. The aims of this work are (1) show the ISFET developed to monitor pH and NH4, (2) show the design of the whole sensor module and (3) show the implementation of the WSN.