The method includes: An access network device sends a plurality of pieces of time division multiplexing mode information to a terminal, where each of the plurality of pieces of time division multiplexing mode information indicates one time division multiplexing mode, and in the time division multiplexing mode, time division multiplexing is performed on a first uplink time domain resource and a second uplink time domain resource, the first uplink time domain resource is an uplink time domain resource of a first carrier; and the second uplink time domain resource is an uplink time domain resource of a second carrier; and the access network device sends first information to the terminal, where the first information activates one of the plurality of time division multiplexing modes indicated by the plurality of pieces of time division multiplexing mode information.