Reducing unnecessary pedestrian-to-vehicle transmissions using a contextual policy

The safety of vulnerable road users (VRU) (e.g., pedestrians, bicyclists) can be improved by sharing their position and context information with vehicles over a wireless communication channel. However, challenges exist in managing transmission in densely populated areas with large numbers of VRUs, since these transmissions may overload the wireless channel leading to transmissions errors and increased battery consumption of the VRU device. This paper hence proposes a contextual transmission policy to address the above challenges. The policy leverages the GPS information available at a personal VRU device to control the message transmission rate for the VRU device. VRUs walking across a street are deemed highly vulnerable and use a larger message transmission rate. Others on the sidewalk are less vulnerable and transmitting fewer messages per time interval. Simulations of a Manhattan VRU scenario show that even with inaccurate GPS readings, significant numbers of transmission can be reduced, which results in a reduction of information age from being 90% of the times less than 1700 msec to 90% of the times less than 710 msec.