Performance investigation and optimization of IEEE802.15.4 for industrial wireless sensor networks

This paper evaluates the performance of IEEE 802.15.4 for industrial wireless sensor networks. The IEEE 802.15.4 protocol has got the ability to provide real time data transmission in wireless sensor networks using guaranteed time slots (GTS) as medium access control mechanism. According to the standard, a maximum of 7 GTSs can be allocated in one superframe. All GTSs are exclusively dedicated to a corresponding node. Hence, the GTS mechanism is rather limited regarding the number of nodes and the needed scalability is missing. In this paper we introduce a new scheduling algorithm called ldquoEarliest Due Date GTS Allocationrdquo which can be implemented at the medium access control layer. Using this scheduling scheme and an appropriate scheduler, the GTS mechanism is enhanced, in order to enable a deployment in large scale networks with real-time requirements.