A transmission and reception apparatus and method for use in a wireless
communication system, and an apparatus and method for adaptively transmit
and receive a signal according to channel state in a wireless
communication system. An apparatus for adaptively performing transmission
according to a state of a channel transmitted from a transmitter to at
least one receiver includes a signal to interference ratio estimator for
estimating a signal to interference ratio of the channel using a signal
transmitted from the at least one receiver; and an adaptive transmitter
for transmitting data to the at least one receiver on a basis of the
estimated signal to interference ratio.