Receiving apparatus and method thereof

A receiving apparatus comprising:

• a light receiving unit which receives an optical signal and generates a current signal dependent on the optical signal;
• a conversion unit which converts the current signal into a voltage signal;
• a first threshold voltage generation unit which generates a first threshold voltage lower than substantially half of a peak voltage of the voltage signal;
• a second threshold voltage generation unit which generates a second threshold voltage lower by the first threshold voltage than the peak voltage of the voltage signal;
• a selection unit which, when the voltage signal changes from a first potential to a second potential higher than the first potential, selects and outputs the second threshold voltage after the voltage signal exceeding the first threshold voltage, and when the voltage signal changes from the second potential to the first potential, selects and outputs the first threshold voltage after the voltage signal falling below the second threshold voltage;
• and
• a comparison unit which compares the voltage signal with the first or second threshold voltage outputted from the selection unit.