A Build of the Sensor Network for an Environmental Observation in the Toyama Bay^|^mdash;III.^|^mdash;The Test Operation Result and Problem of a Sea Water-Temperature Observation System^|^mdash;

Abstract

Currently, the water temperature and salt have been often observed in the Toyama bay. In these projects are being used the shipping, the buoy, and the remote sensing. We have proposed the observation system with a Wireless Sensor Network (WSN). This system has an advantage that a range of observations and the contents of sensing can be changed flexibly. For the purpose of clearing the problems of the proposal system, the sea water temperature in the park and marina near a Toyama new port has been observed twice, in August, 2011 and March, 2012. The experimental result showed that the observation using WSN was effective because of proper node layout. In this experiment, the proper node interval was less than about 500[m]. When the distance was longer than it, the receiving rate dropped, and the network was disconnected. Furthermore, since the error of the water-temperature sensor was more than 3[°C], it is necessary to improve this within ±0.5[°C].