Operation Scale Expansion Method Research for Smart Lamp Pole ZigBee System

In engineering, a smart street lighting IoT system must maintain effective communications not only among lamp poles but also between each lamp pole and sensors near it. This requires the system scalable for satisfying high real-time requirement, refresh cycle limitation and communication rate constraint. To obtain such a scalable system, this paper designs a hierarchical ZigBee communication, and proposes a multi- channel clustering method. The coordinator interacts with every cluster head node in master-slave mode, and the nodes in cluster exchange information with each other in hidden token mode. For those two operation modes, a parallel synchronization mechanism is then established by using multi-channel communication. For system design optimization, a mathematical formula is presented to calculate the number of the operation nodes that guarantees both real-time control requirements and refresh cycle condition. Finally, experiments are implemented, verifying that using the proposed method can effectively obtain a scalable system.