Patent ID: 6785477
Filing Date: 2004-08-31
Classification: H03F,H04B

Abstract:
An optical receiver, comprising:a photodetector to which an optical modulated signal is input and which outputs photoelectric current; a preamplifier the input terminal of which is connected to an anode terminal of the photodetector, which converts a current signal to a voltage signal and outputs the voltage signal; an automatic gain controllable amplifier that keeps the amplitude of the voltage signal output from the preamplifier at a predetermined value; means for processing a signal output from the automatic gain controllable amplifier and acquiring predetermined digitalized electric information; and a variable negative capacitor connected to the anode terminal of the photodetector, wherein: the variable negative capacitor generates negative capacitance at the input terminal of the preamplifier and the quantity of the negative capacitance is variable according to a control voltage.