International audienceToday, communicating devices are widespread and the IoT trend tends to make them incontrovertible in our everyday life. According to some forecast, 50 billions of these devices should be available by 2020. The first consequence is that this massive advent of connecting devices will have a huge impact on the world energy consumption. In this context, it is then mandatory to deal with power as soon as possible in the design process of such systems. This paper presents a new power estimation approach at early design phases which is based on the decomposition of a digital system into a set of basic operators. Each operator has its own model which estimates both switching activity and power consumption. By interconnecting s...