Patent ID: 7869552

Claim:
A receiving apparatus for receiving communication data from a transmitting apparatus, wherein: a specific code pattern and a predetermined repetitive pattern which has a plurality of positions wherein the polarity of the repetitive pattern is changed are each inserted in the communication data at predetermined intervals; the receiving apparatus comprises: a first frequency difference measurement device for measuring a first frequency difference between a receiving clock of the receiving apparatus and a transmission clock provided to the communication data, based on a detection interval between the specific code pattern which is detected early, and the specific code pattern which is detected later; a second frequency difference measurement device for measuring a second frequency difference between the receiving clock of the receiving apparatus and the transmission clock provided to the communication data, based on phase data which is obtained in accordance with the positions where the polarity of the repetitive pattern is changed; and a frequency adjustment device for adjusting a frequency of the receiving clock based on at least one of the measured first frequency difference and the measured second frequency difference so that the frequency of the receiving clock substantially coincides with a frequency of the transmission clock; and when the first frequency difference is equal to or less than a predetermined value, the frequency adjustment device adjusts the frequency of the receiving clock based on the second frequency difference.