Abstract: An on-board unit (OBU) with a driving-assistance function to be installed on a vehicle includes at least one wireless communication unit and a processing unit. The processing unit receives information of at least one first traffic signal and at least one second traffic signal respectively from their RSUs through the at least one wireless communication unit. The first traffic signal is installed at a first intersection, the at least one second traffic signal is installed at a second intersection, and the vehicle is closer to the first intersection than to the second intersection. The processing unit generates a suggested speed range, within which the vehicle may travel to allow the same to pass through the first intersection and the second intersection without stopping, according to the information of at least one first traffic signal and the at least one second traffic and vehicle position information of the vehicle.

Abstract: An on-board unit (OBU) with a driving-assistance function to be installed on a vehicle includes at least one wireless communication unit and a processing unit. The processing unit receives information of at least one first traffic signal and at least one second traffic signal respectively from their RSUs through the at least one wireless communication unit. The first traffic signal is installed at a first intersection, the at least one second traffic signal is installed at a second intersection, and the vehicle is closer to the first intersection than to the second intersection. The processing unit generates a suggested speed range, within which the vehicle may travel to allow the same to pass through the first intersection and the second intersection without stopping, according to the information of at least one first traffic signal and the at least one second traffic and vehicle position information of the vehicle.

Abstract: A driving assisting system includes a traffic signal controller, an RSU, at least one data transmission interface and an OBU. The RSU is electrically connected to the traffic signal controller. The OBU is installed on a vehicle. The traffic signal controller controls a traffic light, which is located at an intersection. The RSU obtains traffic-light information of the traffic light from the traffic signal controller. The OBU receives the traffic-light information through the at least one data transmission interface from the RSU. The OBU generates dynamic vehicle information of the vehicle. The OBU determines if the vehicle will be positioned at a key zone of the intersection when the traffic light switches according to the dynamic vehicle information and the traffic-light information. The OBU responds according to a key zone type of the key zone when the vehicle is positioned at the key zone of the intersection.