Synchronization system and method for transmission and reception in audible frequency range-based sound communication, and apparatus applied thereto

A receiving apparatus for acoustic data communication in audible frequency range, the apparatus comprising:

• a transforming unit configured to receive an audio signal, the audio signal being formed by inserting synchronization data into a frequency-domain signal transformed based on a first-type transform and being inverse-transformed, based on the first-type transform, into a time-domain signal, and to transform the audio signal into a frequency-domain signal based on a second-type transform;
• a normalizing unit configured to normalize a size of coefficient of the frequency-domain signal transformed based on the second-type transform to a predetermined size;
• an inner product calculating unit configured to calculate an inner product of the normalized signal and a pre-generated synchronization signal;
• an inverse-transforming unit configured to inverse-transform, based on the second-type transform, a result of the inner product;
• a correlation unit configured to generate a correlation value by overlapping the inverse-transformed signal with a previous inversed transformed signal in a predetermined interval;
• and
• a synchronization point detecting unit configured to determine a point of the synchronization data based on a point of a peak in the correlation value.