| 摘要 |
PURPOSE:To provide the monitoring device with high accuracy without a temperature dependency with respect to a light receiving level monitoring device in an optical transmission repeater. CONSTITUTION:In the optical receiver provided with an AGC function having an oscillator 11, a gate 17 controlling the connection of its signal, a gain variable amplifier circuit 12 receiving the gate output, a smoothing circuit 16 detecting an envelope of an amplitude modulation signal, an amplitude detection circuit 9 detecting the amplitude of the output via a band pass filter 8, and a comparator amplifier for the signal, the signal of the oscillator 11 is superimposed on an APD control voltage, the signal is extracted from a signal output 14 and converted into a control signal of the gain variable circuit 12 and the control signal is used for a monitor output as a feature. |
