Physical layer protocol data unit transmission method and related apparatus

A first communication apparatus, wherein the first communication apparatus comprises:

• a receiving unit, configured to receive a trigger frame from a second communication apparatus, wherein the trigger frame indicates a first resource allocated to the first communication apparatus, the first resource comprises N resource subunits, the trigger frame comprises first indication information, the first indication information separately indicates whether the first communication apparatus is allowed to perform TB PPDU transmission on each of the N resource subunits when the first communication apparatus performs trigger-based physical layer protocol data unit (TB PPDU) transmission by using some of the N resource subunits, and N is an integer greater than or equal to 1;
• and
• a sending unit, configured to send a TB PPDU to the second communication apparatus on some of the N resource subunits based on the first indication information.

A second communication apparatus, wherein the second communication apparatus comprises:

• a sending unit, configured to send a trigger frame to a first communication apparatus, wherein the trigger frame indicates a first resource allocated to the first communication apparatus, the first resource comprises N resource subunits, the trigger frame comprises first indication information, the first indication information separately indicates whether the first communication apparatus is allowed to perform trigger-based physical layer protocol data unit (TB PPDU) transmission on each of the N resource subunits when the first communication apparatus performs transmission by using some of the N resource subunits, and N is an integer greater than or equal to 1;
• and
• a receiving unit, configured to receive, from the first communication apparatus, a TB PPDU sent on some of the N resource subunits.