Method and apparatus for transmitting a feedback channel in a wireless communication system
Provided are a method and an apparatus for transmitting a feedback channel in a wireless communication system. User equipment measures a modulation-and coding scheme (MCS) level obtained by quantizing a carrier-to-interference-plus-noise ratio (CINR), maps feedback information including the MCS level to a feedback channel, and transmits the feedback channel.
1. A method of transmitting a feedback channel in a wireless communication system, the method comprising:
measuring a modulation and coding scheme (MCS) level obtained by quantizing a carrier to interference plus noise ratio (CINR) of a mobile station,
wherein the CINR is a differential CINR which is a difference value between the CINR and a reference CINR;
mapping feedback information, including the MCS level, to the feedback channel,
wherein the mapping feedback information to the feedback channel comprises mapping a feedback orthogonal sequence corresponding to the measured MCS level, from among a plurality of different orthogonal sequences, to 3 distributed hybrid automatic repeat request (HARM) mini-tiles (HMTs) which are uplink resources allocated to the feedback channel, wherein the HMT comprises 2 contiguous subcarrier and 2 OFDM symbols; and
transmitting the feedback channel.
2. The method of claim 1 , wherein the MCS level is represented by 2 bits.
3. The method of claim 1 , wherein the MCS level is a measurable MCS level in a group, if the mobile station is allocated to the group including a plurality of mobile stations.
4. The method of claim 1 , wherein the mapping the feedback information to the feedback channel comprises:
generating a feedback sequence based on the feedback information,
mapping the feedback sequence to a feedback symbol by modulating and repeating the generated feedback sequence, and
mapping the feedback symbol to a subcarrier allocated to the feedback channel.
5. The method of claim 4 , wherein:
uplink resources allocated to the feedback channel comprise 3 distributed tiles, and
the tile comprises 2 contiguous subcarrier and 6 orthogonal frequency division multiplexing (OFDM) symbols.
6. The method of claim 4 , wherein the feedback information is multiplexed with feedback information of at least one another user and mapped to the feedback channel.
7. The method of claim 1 , wherein a number of the plurality of different orthogonal sequences is extended.
8. The method of claim 1 , wherein some pieces of multiple-input multiple-output (MIMO) information or bandwidth request information are indicated by using some of the plurality of different orthogonal sequences.
9. An apparatus for transmitting a feedback channel in a wireless communication system, the apparatus comprising:
a radio frequency (RF) unit configured to transmit the feedback channel; and
a processor, coupled to the RF unit, and configured for:
measuring a modulation and coding scheme (MCS) level obtained by quantizing a carrier to interference plus noise ratio (CINR) of a mobile station,
wherein the CINR is a differential CINR which is a difference value between the CINR and a reference CINR, and
mapping feedback information, including the MCS level, to the feedback channel,
wherein the mapping the feedback information to the feedback channel comprises mapping a feedback orthogonal sequence corresponding to the measured MCS level, from among a plurality of different orthogonal sequences, to 3 distributed hybrid automatic repeat request (HARM) mini-tiles (HMTs) which are uplink resources allocated to the feedback channel, wherein the HMT comprises 2 contiguous subcarrier and 2 OFDM symbols.
10. The apparatus of claim 9 , wherein the MCS level is represented by 2 bits.
11. The apparatus of claim 9 , wherein the MCS level is a measurable MCS level in a group, if the mobile station is allocated to the group including a plurality of mobile stations.