A ZigBee controlled lighting system with improved resistance to wireless interference

Various wireless technologies, such as Wi-Fi, Bluetooth, and ZigBee (802.15.4), work in the 2.4GHz ISM (industrial, scientific and medical) band. As a low cost and low power wireless protocol, ZigBee is easy to be interfered by the other wireless communications such as Wi-Fi. In this paper, a new system architecture for ZigBee controlled lighting system is proposed to protect ZigBee networks against Wi-Fi interference. A router controller instead of an end-device remote controller is used to send the commands to all other nodes. In addition, a new algorithm called ZPA is adopted in the router controller by utilizing the RTS/CTS mechanism of Wi-Fi devices. Theoretical analysis indicates the packet loss rate is reduced by two aspects of this new architecture: Improved SINR and short collision time. Experiments on our testbed show that this system architecture is effective to reduce the PER of ZigBee networks under Wi-Fi interference. Especially, only requiring modifications to the router controller is practical for realistic deployment of ZigBee controlled lighting system.