Real-time WSN communication for access control applications

One of the persisting requirement in todays Wireless Sensor Networks is the real-time QoS requirement for specific applications. In this paper the analysis of WSN real-time QoS ability for the application of access control backbone communication network was presented in respect to the existing WSN based on ZigBee communication protocol and XBee WSN modules. The real-time communication was analyzed in respect to the round trip time (delay) required for the WSN node to transmit the data to the cluster head, to process the data and return the acknowledge. A rating QoS metrics was proposed based on RTT parameter and various other parameters that have impact on the real-time communication. Further on, the impact of the distance between the End node and the Cluster head is analyzed on XBee WSN modules. The improvement of the QoS is presented by analyzing different hardware and software solutions for the data processing at the Cluster head location and proposing new hardware architecture based on ARM embedded system and Linux OS. It was concluded that by replacing the existing hardware of the Cluster head node it is possible to improve QoS and enable real-time communication for the specific application.