Wireless Sensor Networks for microclimate telemonitoring using ZigBee and WiFi

Wireless Sensor Network is increasingly popular in the field of microclimate monitoring due to its promising capability. Wireless Sensor Network using many wireless communication protocols, such as Bluetooth, ZigBee, ultra wideband, and WiFi. WiFi has many advantages, i.e high data rate and long range distances, but it requires a high power. ZigBee uses less power, but it offers low data rate and short range distances. This paper presents the application of ZigBee and WiFi networks for microclimate monitoring. Data of air temperature and humidity are collected using ZigBee-WSN and then the data are transmitted from the observed area to the monitoring center using WiFi transceiver. Air temperature sensors have average error 1.9% and humidity sensors have average error 3.8%. This system needs ZigBee - WiFi interface that convert the data format from ZigBee protocol into TCP/IP protocol. Maximum distance communication of ZigBee protocol is ± 200m in the outdoor area with many obstacles. The interface system can communicate properly when the baud rate is 9600bps.