Communication method and apparatus
A communication method and apparatus that is used in fields such as V2X, an internet of vehicles, intelligent driving, and assisted driving. The method includes a first terminal apparatus detects SCI from at least one second terminal apparatus, to determine a first resource. The first terminal apparatus sends, to the third terminal apparatus, first information for triggering determining of second information, and receives the second information from the third terminal apparatus. The first terminal apparatus determines, based on the first resource and the second resource, the resource for sending the data. The first terminal apparatus selects, based on a sensing result of the first terminal apparatus and the resource recommended by the third terminal apparatus, the resource for sending the data, so that both interference around the first terminal apparatus and interference around the third terminal apparatus are considered, thereby reducing interference and improving communication quality.
1 . A communication method, comprising:
detecting, by a first terminal apparatus, sidelink control information (SCI) from at least one second terminal apparatus to determine a first resource that includes a resource available to send data to a third terminal apparatus;
sending, by the first terminal apparatus, first information to the third terminal apparatus, wherein the first information is configured to trigger the third terminal apparatus to perform a resource assistance procedure by determining second information, wherein the second information is an assistance information and indicates a second resource, and the second resource is for determining a resource for sending the data to the third terminal apparatus;
receiving, by the first terminal apparatus, the second information from the third terminal apparatus;
determining, by the first terminal apparatus, a third resource based on the first resource and the second resource indicated by the assistance information; and
sending first data to the third terminal apparatus on the third resource, wherein the second resource is a resource unavailable to send the first data.
2 . The method according to claim 1 , wherein: the sending the first information to the third terminal apparatus comprises: sending second control information to the third terminal apparatus, wherein the second control information includes third SCI and fourth SCI, the third SCI is 1st-stage SCI, the fourth SCI is 2nd-stage SCI, and the fourth SCI includes the first information, or the third SCI includes the first information.
3 . The method according to claim 2 ,
wherein: the third SCI includes a seventh field that is configured to indicate whether third information exists or a manner of obtaining the third information; or
the fourth SCI includes an eighth field that is configured to indicate whether the third information exists or a manner of obtaining the third information, wherein
the third information is for determining the second resource, and the third information includes at least one of:
a sending period of the first data;
a priority of the first data;
a data packet size of the first data; or
a delay requirement of the first data;
the method further comprising:
obtaining the sending period of the first data wherein: the sending period:
is indicated by the third SCI;
is indicated by the fourth SCI;
is configured by a higher layer; or
is carried by a media access control element (MAC-CE);
obtaining the priority of the first data wherein the priority:
is indicated by the third SCI;
is indicated by the fourth SCI;
is configured by the higher layer; or
is carried by a MAC-CE;
obtaining the data packet size of the first data wherein: the data packet size:
is indicated by the fourth SCI;
is implicitly indicated by a fourth resource;
is configured by the higher layer; or
is carried by a MAC-CE; and
obtaining the delay requirement of the first data wherein the delay requirement:
is indicated by the fourth SCI;
is configured by the higher layer; or
is carried by a MAC-CE.
4 . The method according to claim 3 , wherein the delay requirement of the first data is a start location or an end location of a resource selection window corresponding to the second resource.
5 . A communication apparatus being a first terminal apparatus, comprising:
a processor, configured to detect sidelink control information (SCI) from at least one second terminal apparatus, to determine a first resource that includes a resource unavailable to send data to a third terminal apparatus; and
a transceiver, configured to send first information to the third terminal apparatus, wherein the first information is configured to trigger the third terminal apparatus to perform a resource assistance procedure by determining second information, wherein the second information is an assistance information and indicates a second resource, the second resource is for determining a resource for sending the data to the third terminal apparatus, and receive the second information from the third terminal apparatus, wherein:
the processor is further configured to determine a third resource based on the first resource and the second resource indicated by the assistance information; and
the transceiver is further configured to send first data to the third terminal apparatus through the third resource, wherein the second resource is a resource unavailable to send the first data.
6 . The apparatus according to claim 5 , wherein the transceiver is configured to: send second control information to the third terminal apparatus, wherein the second control information includes third SCI and fourth SCI, the third SCI is 1st-stage SCI, the fourth SCI is 2nd-stage SCI, and the fourth SCI includes the first information, or the third SCI includes the first information.
7 . The apparatus according to claim 6 , wherein:
the third SCI includes a seventh field that is configured to indicate whether third information exists or a manner of obtaining the third information; or
the fourth SCI includes an eighth field that is configured to indicate whether the third information exists or a manner of obtaining the third information, wherein
the third information is configured to determine the second resource, and the third information includes at least one of:
a sending period of the first data;
a priority of the first data;
a data packet size of the first data; or
a delay requirement of the first data;
the transceiver further configured to obtain the sending period of the first data wherein: the sending period:
is configured to be indicated by the third SCI;
is configured to be indicated by the fourth SCI;
is configured by a higher layer; or
is carried by a media access control element (MAC-CE);
the transceiver further configured to obtain the priority of the first data wherein the priority:
is configured to be indicated by the third SCI;
is configured to be indicated by the fourth SCI;
is configured by the higher layer; or
is carried by a MAC-CE;
the transceiver further configured to obtain the data packet size of the first data wherein:
the data packet size is configured to be indicated by the fourth SCI;
is configured to be implicitly indicated by a fourth resource;
is configured by the higher layer; or
is carried by a MAC-CE; and
the transceiver further configured to obtain the delay requirement of the first data wherein the delay requirement:
is configured to be indicated by the fourth SCI;
is configured by the higher layer; or
is carried by a MAC-CE.
8 . The apparatus according to claim 7 , wherein the delay requirement of the first data is a start location or an end location of a resource selection window corresponding to the second resource.