A method includes: determining a frame structure used for information transmission in the TDD system, where each frame based on the frame structure includes N subframes with a timing length of K subframes, one super frame includes M consecutive subframes, M is a common multiple of N and 2K, each super frame includes at least one downlink-only subframe, and further includes at least one of an uplink-only subframe, a type-1 subframe, or a type-2 subframe, the downlink-only subframe includes a downlink symbol and no uplink symbol, the type-1 subframe includes an uplink symbol and a downlink symbol with uplink symbols less than downlink symbols, the type-2 subframe includes an uplink symbol and a downlink symbol with uplink symbols more than downlink symbols, and the uplink-only subframe includes an uplink symbol and no downlink symbol; and sending and/or receiving a message based on the frame structure.