Abstract: Embodiments of the present invention disclose a resource allocation method, a transmission method, and apparatuses. The resource allocation method comprises: sending a scheduling instruction, wherein the scheduling instruction comprises: information that is associated with at least two carriers in an unlicensed spectrum allocated to transmission of a user equipment; determining at least one available carrier in the at least two carriers; and sending a physical indication signal on the at least one available carrier, wherein the physical indication signal is used to occupy the at least one available carrier.