Optical receiver
First Claim
1. An optical receiver for converting an optical signal received into an electrical signal to output the electric signal, comprising:
- a photoelectric converter having an electric current signal output;
a preamplifier connected to receive the current signal output by the photoelectric converter, and having a voltage signal output;
an amplifier having a limiting function and connected to receive the voltage signal output by the preamplifier, to linearly amplify the voltage signal when the voltage signal is different from a reference voltage by less than or equal to a predetermined voltage, and to limitedly amplify said voltage signal when the voltage signal is different from the reference voltage by more than the predetermined voltage; and
an automatic-gain-control amplifier connected to receive and amplify the output voltage signal of said amplifier having the limiting function, to output a signal having a constant swing, wherein the output signal swing of said amplifier having the limiting function satisfies the following relation within a desired dynamic range of said optical signal;
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Accused Products
Abstract
An optical receiver generates a voltage signal having a predetermined swing from a current signal, and feeds the voltage signal to a decision circuit. An optical receiving element receives the input optical signal, converts the optical signal to a current signal, and provides the current signal to a preamplifier, which converts the input current signal into a voltage signal. The voltage signal is input to an amplifier having a limiting function, which linearly amplifies the voltage signal when the swing of the voltage signal is smaller than a predetermined value, and limitedly amplifies the voltage signal when the voltage signal is greater than the predetermined value. An automatic-gain-control amplifier receives the output from the amplifier with the limiting function, and amplifies the input voltage signal to a voltage signal having a constant swing. The decision circuit receives the output of the automatic-gain-control amplifier and decides the binary nature of the voltage, and thus of the input optical signal.
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Citations
6 Claims
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1. An optical receiver for converting an optical signal received into an electrical signal to output the electric signal, comprising:
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a photoelectric converter having an electric current signal output;
a preamplifier connected to receive the current signal output by the photoelectric converter, and having a voltage signal output;
an amplifier having a limiting function and connected to receive the voltage signal output by the preamplifier, to linearly amplify the voltage signal when the voltage signal is different from a reference voltage by less than or equal to a predetermined voltage, and to limitedly amplify said voltage signal when the voltage signal is different from the reference voltage by more than the predetermined voltage; and
an automatic-gain-control amplifier connected to receive and amplify the output voltage signal of said amplifier having the limiting function, to output a signal having a constant swing, wherein the output signal swing of said amplifier having the limiting function satisfies the following relation within a desired dynamic range of said optical signal;
- View Dependent Claims (2, 3, 4, 5, 6)
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Specification