Towards a design framework for heterogeneous Wireless Sensor Networks

Wireless Sensor Networks consist of resource-constrained (energy, memory and processing) sensor nodes that are deployed at different locations, in order to monitor physical or environmental conditions. Several limitations exist nowadays, at simulation and at programming level, especially for heterogeneous Wireless Sensor Networks (composed of different hardware devices). Indeed, to optimize a self-organized network, it is essential to be able to exchange functionalities between nodes. First, it is difficult to explore design space with accurate hardware-level models for network-level simulations since these two aspects have very different levels. We propose a simulator - based on SystemC language- that allows such explorations. It is composed of a library of electrical devices and software stacks, experimentally validated. More and more sophisticated software support is implemented in our simulator. As trend is to deploy heterogeneous nodes, it becomes a challenge to consider energy-aware reprogramming of different nodes, and to be able to simulate this aspect. We propose a new solution -cross-architecture in-situ compilation- that allows firmware update for functionality exchange, and that is being integrated in the simulator.