and broadcast service block is responsible for coordination, scheduling, and distribution of the E-MBS content to the subscribed users in the relay coverage area. The relay functional block includes procedures to maintain relay paths. The self-organization block performs functions to support the RS self-configuration and the RS self-optimization mechanisms which are coordinated by the BS. These functions include procedures to request the relay stations or mobile stations to report measurements for self-configuration and self-optimization, receive measurements from the relay stations or mobile stations, and report measurements to the BS. These functions also include procedures to adjust the RS parameters and configuration for self-configuration and/or opti- mization with or without coordination with the BS. The multi-carrier operation block enables a common MAC entity to control a physical layer that may span over multiple frequency channels at the RS. The RS MAC sub-layer includes the following functional blocks which are related to the physical layer and link control: Physical layer control; Control signaling; Sleep mode management; Quality of service; Scheduling and resource multiplexing; ARQ function; Fragmentation/packing; MAC PDU formation; Data forwarding; Multi-radio coexistence. As shown in Figure 3-16, the physical layer control block manages signaling schemes such as ranging, measurement, reporting, and HARQ feedback at the RS. Based on CQI and HARQ feedback, the physical layer control block estimates channel conditions of RS/MS and performs link adaptation. The control signaling block performs the RS resource allocation and generates control messages. The sleep mode management block manages sleep mode operation of mobile stations serviced by the RS in coordination with the BS. The QoS block performs rate control according to QoS parameters. The CHAPTER 3 IEEE 802. 16m Reference Model and Protocol Structure scheduling and resource multiplexing block which resides in the RS is used to support distributed