Patent ID: 8005182

Claim:
A method of estimating a frequency offset for a downlink frame, the method comprising: estimating a fractional frequency offset and an integer frequency offset of a received signal, respectively; compensating for the estimated fractional frequency offset and determining whether the integer frequency offset is completely estimated; and compensating for the integer frequency offset on the basis of the compensated fractional frequency offset when the integer frequency offset is completely estimated, adding the compensated fractional frequency offset and the compensated integer frequency offset, and compensating for an entire frequency offset for the received signal on the basis of a result of the addition of the compensated fractional frequency offset and the compensated integer frequency offset, wherein the determining of whether the integer frequency offset is completely estimated includes: calculating a value that is obtained by subtracting the fractional frequency offset by a previously estimated fractional frequency offset before estimating the fractional frequency offset; comparing the calculated value and a predetermined frequency reference value; setting the number of frames according to the result of the comparison; and determining whether the integer frequency offset is completely estimated.