Hardware/software co-design for a wireless sensor network platform

Wireless sensor networks have become shared resources providing sensing services to monitor ambient environment. The tasks performed by the sensor nodes and the network structure are becoming more and more complex so that they cannot be handled efficiently by traditional sensor nodes any more. The traditional sensor node architecture, which has software implementation running on a fixed hardware design, is no longer fit to the changing requirements when new applications with complex computation are added to this shared infrastructure due to several reasons. First, the operation behavior changes because of the application requirements and the environmental conditions which makes a fixed architecture not efficient all the time. Second, to collaborate with other already deployed sensor networks and to maintain an efficient network structure, the sensor nodes require flexible communication capabilities. Furthermore, the information required to determine an efficient hardware/software co-design under the system constraints cannot be known a priori. Therefore a platform which can adapt to run-time situations will play an important role in wireless sensor networks. In this paper, we present a hardware/software codesign framework for a wireless sensor platform, which can adaptively change its hardware/software configuration to accelerate complex operations and provides a flexible communication mechanism to deal with complex network structures. We perform real-world measurements on our prototype to analyze its capabilities. In addition, our case studies with prototype implementation and network simulations show the energy savings of the sensor network application by using the proposed design with run-time adaptivity.