BURST SIGNAL RECEIVING CIRCUIT

摘要

PURPOSE:To shorten a preamble length from the viewpoint of transmission efficiency by identifying and reproducing a burst signal with a different amplitude for each ONU(optical network unit) provided with a DC component in the burst transmission system of a PDS (passive double star) system or the like and completing a transient state caused by unipolar/bipolar conversion during a preamble period. CONSTITUTION:The average DC component of a burst signal (b) is detected by a low-pass filter 3 during the preamble period. A detected voltage (c) is held by a sample/hold circuit 4 during a burst period. By calculating difference between the received burst signal (b) and a held voltage (d) while using a differential amplifier 6, a signal (e) canceled the DC component is outputted. A comparator 7 identifies '1' and '0' at the waveform center position of the signal (e). A control circuit 5 outputs a sample command (g) to the sample/hold circuit 4.