INTERFERENCE IMPACTS ON ZIGBEE-BASED WIRELESS MESH NETWORKS FOR BUILDING AUTOMATION AND CONTROL
Wenqi (Wendy) Guo1, William M. Healy2 and MengChu Zhou1
1 Department of Electrical and Computer Engineering, New Jersey Institute of Technology
2 Energy and Environment Division, National Institute of Standards and Technology
ZigBee-Wireless Mesh Networks (ZigBee-WMNs) are recognized as a cost-effective and flexible solution for building automation and control. They have the potential to unify the methods of data communication for sensors, actuators, appliances, and asset-tracking devices. They offer a means to build a reliable but affordable network backbone that supports battery-operated devices with low data rate and low duty cycle to facilitate building automation and control systems (BACs). However, ZigBee operates primarily in the license-free 2.4 GHz ISM (Industrial, Scientific and Medical) band. This feature makes the technology easily applicable, but also potentially vulnerable to interference by other wireless technologies working in this band such as WLAN-systems of IEEE 802.11, Bluetooth, and microwave ovens. This research illustrates the possibilities, advantages, and limitations of applying ZigBee-WMNs in BACs to benefit building occupants. Meanwhile, this research investigates the impacts of interference sources on the performance of IEEE 802.15.4 wireless mesh sensor networks. Several experiments are performed in this work with commercially available equipment. The results give an indication of the mutual interference of the different systems when any two of the networks operate simultaneously and in range.