A digital television receiving system includes a first known data detector, a second known data detector, and a selector. The first known data detector detects a location of a first known data sequence in a broadcast signal by calculating a first correlation value between the broadcast signal and a first reference known data sequence. Similarly, the second known data detector detects a location of a second known data sequence in the broadcast signal by calculating a second correlation value between the broadcast signal and a second reference known data sequence. The selector selects the location information detected by one of the first and second known data detectors with a greater correlation value.