Patent ID: 8644363

Claim:
An apparatus for estimating a channel in a MIMO wireless telecommunication system supporting an OFDM or OFDMA, the apparatus comprising: FFT means for transforming signals of a first channel and a second channel received through a first receiving antenna and signals of a third channel and a fourth channel received through a second receiving antenna, from a time domain to a frequency domain; carrier frequency offset processing means for estimating a carrier frequency offset for a corresponding received signal by using two or more pilots included in at least one received signal among received signals of the first channel to the fourth channel, which are transformed into the frequency domain; time offset processing means for estimating a time offset for a corresponding received signal by using two or more pilots included in at least one received signal among received signals of the first channel to the fourth channel, which are transmitted from the carrier frequency offset processing means or the FFT means; and channel estimating means for estimating a channel of each received signal of the first channel to the fourth channel with a different method according to a subchannel mapping rule by using pilots included in each received signal, which is transmitted from the time offset processing means.