Apparatus and method for transmitting feedback information in broadband wireless access system

A method of operating a receiver for receiving feedback information in a broadband wireless access system, the method comprising:

• obtaining a sounding symbol from an uplink frame received through a first path;
• estimating the sounding symbol;
• and
• obtaining a channel representative value for a second path while estimating the sounding symbol by determining a phase value of the sounding symbol estimation result and obtaining a codebook index bit for the second path by using the determined phase value.

A transmitter apparatus for transmitting feedback information in a broadband wireless access system, the apparatus comprising:

• a channel estimator for estimating a channel of a second path based on information of a received downlink frame;
• a codebook selector for obtaining a channel representative value corresponding to the estimated channel of the second path by selecting a codebook index based at least in part on a correlation between the estimated channel of the second path and a plurality of predetermined codebook indices;
• a sounding symbol modulator for modulating the channel representative value by spreading the channel representative value to a sounding symbol to be transmitted;
• and
• a modem for transmitting the modulated sounding symbol through a first path.