Abstract: A communication method and a communications apparatus are provided. The communication method includes: sending, by a terminal device, a first indication message, where the first indication message is used to indicate a first time type and/or a first time precision, or the first indication message is used to indicate an access network device to send time information to the terminal device; receiving, by the terminal device, the time information; and synchronizing, by the terminal device, a time of the terminal device based on the time information. Correspondingly, a communications apparatus is further provided. According to the embodiments of this application, the terminal device can obtain, based on requirements of different application scenarios, a time type and/or time precision preferred by the terminal device.

Abstract: This application discloses a road constraint determining method and apparatus, applied to the intelligent driving field, and in particular, to a sensor in an advanced driver assistance system ADAS or an autonomous driving system, for example, radar and/or a photographing apparatus. In this method, a moving state of a target is determined based on detection information of the target; at least one road geometry of a road on which the target is located is determined based on the detection information of the target; and a road constraint of the target is determined based on the at least one road geometry and the moving state of the target. The road constraint includes at least one of a road direction constraint and a road width constraint. According to the solutions in this application, road constraint determining accuracy can be improved, and target tracking accuracy can be further improved.

Abstract: Embodiments of this application provide a communication method and a communications apparatus. The communication method includes: sending, by a terminal device, a first indication message, where the first indication message is used to indicate a first time type and/or a first time precision, or the first indication message is used to indicate an access network device to send time information to the terminal device; receiving, by the terminal device, the time information; and synchronizing, by the terminal device, a time of the terminal device based on the time information. Correspondingly, a communications apparatus is further provided. According to the embodiments of this application, the terminal device can obtain, based on requirements of different application scenarios, a time type and/or time precision preferred (prefer) by the terminal device.