Patent ID: 9747799
Date: 2017-08-29
CPC Classifications: G08G

Claim:
1. A radio device that is mountable in a vehicle designed to run on roads, comprising: a receiver that receives, from another radio device designed to run on roads, a packet signal including at least position information of another vehicle in which the other radio device is mounted; a storage device that stores position information of intersections where roads meet each other; and a processor operative to: acquire position information of the vehicle in which the radio device is mounted; estimate a time taken for the vehicle and the other vehicle to encounter each other based on the acquired position information and the received position information included in the packet signal; derive a distance between the vehicle and the other vehicle based on the acquired position information and the received position information included in the packet signal; determine an encounter with the other vehicle when the estimated time is equal to or less than a first threshold value or when the derived distance is equal to or less than a second threshold value; determine a no encounter with the other vehicle when the estimated time is more than the first threshold value or when the derived distance is more than the second threshold value; provide notification of the encounter with the other vehicle when the estimated time is equal to or less than a first threshold value or when the derived distance is equal to or less than a second threshold value; and provide notification of the no encounter with the other vehicle when the estimated time is more than the first threshold value or when the derived distance is more than the second threshold value, wherein when deriving the distance, the processor is further operative to derive, as the distance between the vehicle and the other vehicle, a distance between the vehicle and the intersection based on the acquired position information and the stored position information of the intersections when there is an intersection between the vehicle and the other vehicle.