Performance evaluation of a ZigBee-based wireless sensor network for wide area network micro-grid applications
University of New Brunswick
With low cost and power consumption attributes, plus large-scale wireless networking capabilities, the ZigBee platform is a strong candidate for Wireless Sensor Network (WSN) applications. However, due to low transmit power, ZigBee sensors have a limited Wide Area Network (WAN) capability where long-range data transmission is required. Extending the ZigBee-based WSN coverage increases the overall deployment flexibility including that needed for micro-grid applications where localized monitoring of energy devices and centralized energy management are needed. In order to meet this requirement, a ZigBee controller node (ZCN) was developed with long-range communications capabilities giving ZigBee sensors an access point to the Internet or a centralized data server. To facilitate the real-time processing of information, the WSN latency was managed by the Earliest Deadline First and First Come First Serve prioritization algorithms implemented in the ZCN. The performance of the prioritization mechanisms was investigated and the reliability of the ZCN with its network performance was evaluated in terms of transmission latency, packet drop and retry rates, and processing time. A ZigBee-based WSN was simulated in OMNeT++ to verify the network behavior of the ZCN. Also, a mathematical model of the transmission latency from the sensor nodes in a ZigBee-based network to a data storage facility was derived from identified latency sources.