Event driven duty cycling: an efficient power management scheme for a solar-energy harvested road side unit

In this study the authors deal with different issues resulting from the practical implementation of a self-powered road side unit (RSU). Here, the authors suggest that a RSU can harvest the energy needed for its work from the surrounding environment, especially the solar energy. Such a suggestion permits to install the RSUs in any place without considering the power supply availability and hence, extensive area is covered by the vehicular ad hoc networks (VANET) infrastructure. UBICOM IP2022 network processor is chosen to realise the proposed RSU. A comprehensive design steps are illustrated and the required values of the system elements, that is, the number of solar cell panels, the capacity of the battery cells, etc. are adjusted to fulfil the design purposes. In order to reduce the power utilisation of the recommended RSU and to lengthen the duration of their batteries, a new distributed power management scheme called event driven duty cycling was suggested and installed locally in the RSUs in order to decrease their power consumption and to extend the life time of their batteries. The suggested method was compared with other duty cycling methods and with other real world implementations to show its usefulness in building a green VANET infrastructure.