Hybrid-powered internet-of-things for infrastructure-to-vehicle communication

While autonomous and networked vehicles are being designed to navigate under different driving conditions, there is an emerging need for the infrastructure (roadways) to communicate with the vehicles so as to reliably convey current road conditions. Wireless sensors or devices that are embedded inside the infrastructure can facilitate real-time information exchange, however, its design requires a careful trade-offs between different factors such as operational lifetime, communication distance and latency. In this paper, we discuss three particular methods for establishing a radio-frequency communication link within our previously reported framework of infrastructural Internet-of-Things (i-IoT). We propose a figure of merit (FOM) to compare and contrast different topologies of infrastructure-to-vehicle (I2V) communication devices which includes the traditional battery-powered approach, a passive approach that harvests RF energy for its power source and only polls a sensor when power is available, and a hybrid approach that leverages an RF harvesting mechanism to activate a battery-powered sensor. The estimated FOM suggests that a hybrid approach is the most pragmatic for the particular use case of road-condition monitoring.