Patent ID: 7551692

Claim:
A frequency recovery apparatus for use in a digital broadcast receiver for receiving a digital broadcast signal transmitted according to an orthogonal frequency division multiplexing (OFDM) scheme, comprising: a division window for dividing first data units, which are transformed from OFDM symbols into frequency-domain values and second data units which respectively correspond to the first data units delayed by time intervals respectively, and passing only parts of the data units from among data intervals of the first data units and the second data units, passing data units of a predetermined-sized data interval in the first data units and data units of a pull-in range interval positioned at front and rear parts of the predetermined-sized data interval, allowing data units of remaining intervals other than the predetermined-sized data interval and the pull-in range interval to be padded to zero, and generating a padding result; a pilot pattern generator for generating a pilot pattern in the divided first data units; and a cross-correlator for performing correlation between a part of the first data units and a part of the second data units from the division window at a individual position of the pilot pattern generated from the pilot pattern generator, and generating a correlation resultant values.