Bảng Một số lĩnh vực của tiêu đề MAC mà không có trọng tải loại I. (Căn cứ vào tham khảo [2]) Tên EC HT Loại Length nội dung Tiêu đề HCS CID (bit) 1 1 3 19 16 8 Mô tả Tiêu đề Loại. Một tiêu đề mà không cần tải trọng Đối với một tiêu đề MAC mà không có tải trọng, | MAC Functions and MAC Frames 99 MAC Header 6 bytes No Payload No CRC 1 2 Type 3 - 1 1 1 1 1 1 1 1 1 1 HC MSB 11 1 1 1 1 1 1 1 HC LSB 8 1 1 1 1 1 1 1 CID MSB 8 1 1 1 1 1 1 1 CID LSB 8 1 1 1 1 1 1 1 HCS 8 1 HT 1 2 EC 0 HC Header Content Figure Header format without payload Type I. Based on Reference 2 . Table Some fields of the MAC header without payload Type I. Based on Reference 2 . Name Length bits Description HT 1 Header Type. One for the header without payload EC 1 For a MAC header without payload this bit indicates whether it is Type I or II Type 3 Indicates the type of header without payload see below Header content 19 Header content function of the Type field value CID 16 Connection IDentifier HCS 8 Header Check Sequence same as for the generic MAC header number of bytes requested the CID indicates the connection for which the uplink bandwidth is requested. Aggregate and incremental BR types will be seen in Chapter 10. The SN report header is sent by the SS in the framework of the ARQ procedure. In the MAC header format without payload Type II the header is changed with regard to Type I. It is used for some feedbacks specific to OFDMA MIMO etc . Table Header format without payload Type I use. Based on Reference 2 . Type field 3 bits MAC header type with HT EC 0b10 000 BR incremental 001 BR aggregate 010 PHY channel report 011 BR with UL Tx power report 100 Bandwidth request and CINR report 101 BR with UL sleep control 110 SN report 111 CQICH allocation request 100 WiMAX Technology for Broadband Wireless Access Generic Frames Transport or Management Frames The payload can contain either a management message or transport data. Specific connections are defined as management connections see Table . These connections carry only management messages. All other connections carry user data or secondary upper layer MAC management data. MAC Subheaders and Special Payloads Use of the remaining Type bits of the generic MAC frame see Table
