Accurate Timeliness Simulations for Real-Time Wireless Sensor Networks

The use of wireless sensor networks is rapidly growing in various types of applications that benefit from spatially distributed data collection. Some of these applications, such as industrial automation, fire detection or health monitoring, have strong timeliness constraints. Since field deployments are difficult to monitor and debug, the development of real-time communication protocols for wireless sensor networks necessitates accurate simulation models. This paper presents open source Omnet++ simulation models based on the IEEE 802.15.4 standard. Four evaluation scenarios are used to compare simulation timeliness and packet error rate results with experimental measurements. The small scale of the scenarios allows to isolate the effect of each system component. The comparison validates the models for timeliness estimates in sensor networks and pinpoints the variability of software implementations in embedded systems as a major cause of differences between simulated and measured results.