What is UIUC and DIUC in wimax??

wimax diuc

hi all..

can anybody plz explain : What is UIUC and DIUC in Wimx 802.16d??
for what purpose they are useful??

uiuc wimax

Hi,
Please read the text below.

Burst is a collection of slots having the same type of FEC (Channel Coding and Modulation). Base station may transmit a burst with FEC = QPSK-1/2 Convolution code or FEC= 16QAM CTC 3/4. When assigning a burst to the mobile station in the uplink or downlink, this information (FEC) has to communicated to the SS so that SS can modulate or demodulate the burst assigned by the BS for uplink or downlink transmission. BS informs the SS of the assigned burst type by a number.
This number (say 4 = QPSK-1/2 Convolution code , 7 = 16QAM CTC 3/4) is called the interval usage code. The burst profile in the downlink burst assignment is communicated through Downlink Interval Usage Code (DIUC) and for uplink through Uplink Interval Usage Code (UIUC). for example, the BS will inform the SS of the burst allocation (collection of slots with same FEC) through DL/UL-MAP and the FEC type (along with few other parameters) will be specified through the DIUC for DL and UIUC for UL. The definition of DIUC or UIUC (like DIUC = 4 means QPSK-1/2 Convolution Burst profile in the Downlink or UIUC = 5 means 16QAM CTC 3/4 burst profilein the Uplink) is informed to all the SS by the BS through a periodic DCD and UCD messages. The definition of the burst profile (like DIUC = 4 can be QPSK or QAM )is left to the operator. Some collection of slots (burst) in the uplink are reserved for ranging. To inform that those collection of slots (burst ) are meant for ranging, UIUC code = 12 (cdma ranging/BW request .This is standard ) is used. UIUC 1-10 is defined by the operator. UIUC = 0 means it's a FAST FEEDBACK burst.


Regards,
Shiva