BS provides the MS with information on its supported component carriers and their configuration; and (2) the MS obtains information regarding a subset of available component carriers, i.e., the assigned carriers, which the BS may utilize in a multi-carrier operation concerning the MS. The MS does not perform any processing on an assigned component carrier until that carrier is activated by the BS. The BS broadcasts the P-SFH/S-SFH on each component carrier with a format similar to that of a single-carrier. The BS also provides the MS with basic radio configuration for all available component carriers through the AAI_MC-ADV (multi-carrier advertisement message) MAC control message. This message contains the component carriers' configurations which are supported by the BS and is periodically broadcast. The multi-carrier configuration information is used by all mobile stations regardless of their multi-carrier or single-carrier capability. Following initial network entry and after obtaining the information about the base station's multi-carrier configuration, a multi-carrier-enabled MS (multi-carrier aggregation or switching) is required to send an AAI_MC-REQ message to the BS. The MS informs the BS of its multi-carrier capability via the parameters defined in the AAI_MC-REQ message. Depending on the mobile station's multi-carrier capability, the BS responds using an AAI_MC-RSP message and assigns one or more secondary component carriers from the set of available carriers to the MS. 11.4 MAC aspects of multi-carrier operation Spectral Mask for Single-Carrier Systems Guard Resource Guard Resource Effective BW = 9.5 MHz (865 sub-carriers, 48 PRUs) BW = 10 MHz (914 sub-carriers, 50 PRUs) Over-sampled BW (IFFT size) = 11.2 MHz (1024 sub-carriers) Relationship between Effective, Transmission, and Over-sampled Bandwidths and Use of Guard Sub-carriers (BW = 10 MHz) Spectral Mask for Aggregated System Spectral Mask for Single-Carrier Systems Unavailable with Unavailable with Guard Resource Emission mask of Guard Resource em