JPH09233027A - Optical transmitter-receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To relieve trouble of adjustment in response to individual characteristics of laser diodes by allowing a reception section of its own station to generate a control signal, sending the control signal to an opposite station and allowing the opposite station to control an optical output of a transmission section based on the control signal. SOLUTION: A current of a light receiving element of a light receiving circuit 4 of its own station 1 is averaged by an averaging circuit 35, and a comparator circuit 37 compares its output potential with an output potential of a reference level generating circuit 36. A gain level of an AGC amplifier circuit 6 and an output potential of a reference level generating circuit 38 are compared by a comparator circuit 39. A control signal generating circuit 40 generates a control signal based on outputs from the comparator circuits 37, 39. The generated control signal is multiplexed with a data signal by a multiplexer circuit 30 and the resulting signal is sent to an opposite station 2 through an optical fiber 3. A multiple signal reproduced by a reception section 15 is demultiplexed into the data signal and the control signal by a demultiplexer circuit 31. The control signal is decoded by a control signal decoding circuit 46 and used to control a bias current and a modulation current in an optical output drive circuit 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transceiver for optical communication which uses an optical fiber as a signal transmission path.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration of a conventional optical transmitter / receiver used in opposition. In FIG. 4, 1 is own station, 2 is partner station of own station 1, 3 is own station 1 and partner station 2
An optical fiber 4 which is a transmission line connecting to the optical fiber 4 is a light receiving circuit of its own station which performs photoelectric conversion using the optical signal from the optical fiber 3 as an input,
5 is a preamplifier circuit of the own station that amplifies the output signal of the light receiving circuit 4 of the own station, 6 is an AGC amplifier circuit of the own station that amplifies the output signal of the preamplifier circuit 5 of the own station to a desired amplitude, 7 Is my station A
The timing extraction circuit of the own station that extracts the clock component from the output signal of the GC amplification circuit 6, and 8 identifies and reproduces the output signal of the AGC amplification circuit 6 of the own station based on the output signal of the timing extraction circuit 7 of the own station Identification and reproduction circuit of own station for outputting signal and clock signal, 9 is light receiving circuit 4 of own station, preamplification circuit 5 of own station, AGC amplification circuit 6 of own station, timing extraction circuit 7 of own station and own station The receiving section of the own station, which comprises the identification and reproduction circuit 8 of 10, the optical output temperature compensating circuit of the own station for preventing the optical output from the own station 1 from being affected by the temperature fluctuation, 11
Is an optical output control circuit of the own station that keeps the optical output level from the own station 1 constant, and 12 is an own station that operates according to the outputs from the optical output temperature compensation circuit 10 of the own station and the optical output control circuit 11 of the own station. Optical output drive circuit, 13 is a light emitting circuit of its own station driven by the optical output drive circuit 12 of its own station, 14 is an optical output temperature compensation circuit 10 of its own station, an optical output control circuit 11 of its own station, and an optical output control circuit of its own station The transmitter of the own station, which is composed of the optical output drive circuit 12 and the light emitting circuit 13 of the own station, 15 is the receiver of the partner station connected to the transmitter 14 of the own station via the optical fiber 3, and 16 is the optical fiber 3. The transmitting section of the partner station connected to the receiving section 9 of the own station through, 17 is the data output terminal of the own station for outputting the output signal of the identification reproduction circuit 8 of the own station, and 18 is the optical output drive circuit 12 of the own station Data input terminal of own station connected to Data output terminal of the partner station to be continued,
Reference numeral 20 is a data input terminal of the partner station connected to the transmitter 16 of the partner station.

Next, the operation will be described. First, the receiving unit 9 of the own station will be described. The optical signal emitted from the transmitting unit 16 of the partner station is received by the light receiving circuit 4 of the own station, converted into a current signal, and then converted into a voltage signal by the preamplifier circuit 5 of the own station. This voltage signal is the AGC amplifier circuit 6 of the own station.
Is amplified to a voltage signal having a constant amplitude. A clock component is extracted from the output voltage signal of the AGC amplifier circuit 6 of the own station by the timing extraction circuit 7 of the own station and the clock component signal is output. The output voltage signal of the AGC amplifier circuit 6 of the own station is output from the data output terminal 17 of the own station to the outside as a data signal by the identification and reproduction circuit 8 of the own station based on the clock component signal of the timing extraction circuit 7 of the own station. It Next, the transmitter 14 of the own station will be described. A data signal externally input from the data input terminal 18 of the local station is input to the optical output drive circuit 12 of the local station and the light emitting circuit 1 of the local station.
3 is driven and is output to the optical fiber 3 as an optical output. The light emitting circuit 13 of the own station is usually composed of a laser diode, and in order to suppress the fluctuation of the optical output due to the temperature fluctuation of the photoelectric conversion efficiency which is the characteristic of the laser diode, the light output control circuit 11 of the own station is also used. In order to suppress the fluctuation of the extinction ratio of the optical output due to the temperature fluctuation of the differential quantum efficiency, which is the characteristic of the optical output temperature compensation circuit 10 of the own station, the optical output drive circuit 12 of the own station drives the light emitting circuit 13 of the own station. Need to. The laser diode generally has a current-light output conversion characteristic as shown in FIG. 5, and the differential quantum efficiencies a1 to a3 and the threshold currents Ith1 to Ith3 change with temperature changes as shown in FIGS. . Therefore, in order to obtain a good optical output waveform when the laser diode is driven, the modulation currents Imod1 to Imod3 corresponding to the differential quantum efficiency at the ambient temperature and the bias currents Ib1 to Ib3 corresponding to the threshold current are passed through the laser diode. Will be required. FIG. 6 shows a conventional configuration of the transmitting unit 14 of the own station using a laser diode, 21 is a laser diode module, 22 is a laser diode, 23 is a monitor photodiode, 24 is a smoothing capacitor, and 25 is an average light output. Reference voltage,
Reference numeral 26 is a temperature sensitive element for compensating the modulation current temperature. In order to keep the maximum optical output PoutPkPk in FIG. 5 uniform, the optical output temperature compensating circuit 10 of the own station using the temperature sensitive element 26 for temperature compensation of the modulating current compensates the modulating current Imod.
Further, in order to keep the average light output PoutAve uniform, the light output control circuit 11 of the own station controls the bias current Ib. Next, the receiver 15 of the partner station and the transmitter 16 of the partner station
Are respectively the receiving unit 9 of the own station and the transmitting unit 1 of the own station described above.
Since it has the same function as that of 4, the description of the operation is omitted.

[0004]

As described above, the laser diode normally used in the light emitting circuit needs to be controlled or compensated according to its characteristic, and the characteristic of the laser diode varies from individual to individual. Therefore, there is a problem that it is inefficient when manufacturing a large number of optical transmitter / receivers because it is necessary to make adjustments according to the above. Further, in communication using an optical fiber as a transmission line, the appropriate transmission light output is determined according to the distance of the transmission line, but in order to measure the transmission distance, the length of the optical fiber is directly measured, or It is necessary to inject light into the optical fiber and measure the bounce of the light to calculate the distance, which is a troublesome process.

The present invention solves the above-mentioned conventional problems, can reduce the labor of adjustment according to the individual characteristics of the laser diode, and can easily reduce the length of the optical fiber used as the transmission path. It is an object of the present invention to provide an optical transmitter / receiver capable of performing various measurements.

[0006]

In the optical transmitter-receiver according to the first aspect of the invention, for example, with respect to the optical output emitted from the partner station, the transmitter of the partner station does not control or compensate for the light output as in the conventional system. , A control signal is generated using a voltage signal obtained by averaging the output current of the light receiving circuit of the own station and a gain level signal of the AGC amplifier circuit of the own station on the receiving section of the own station
The control signal is multiplexed with the data signal and transmitted to the other station,
The optical output of the transmitter is controlled based on the control signal in the partner station.

In the optical transmitter / receiver according to the second aspect of the invention, for example, with respect to the optical output emitted from the partner station, the transmitter of the partner station does not control or compensate for the optical output as in the conventional system, and the optical output of the own station is controlled. The receiving unit generates a control signal using the voltage signal obtained by averaging the output current of the light receiving circuit of the own station and the voltage signal obtained by extracting the AC component of the middle output of the AGC amplifier circuit of the own station, and outputs the control signal. The data signal is multiplexed and transmitted to the partner station, and the optical output of the transmitter is controlled based on the control signal in the partner station.

Further, in the optical transmitter / receiver according to the third aspect of the present invention, the local station transmits a data signal multiplexed with the time difference detection signal, and the partner station transmits the received time difference detection signal again as it is with the data. In the local station, the transmission distance of the fiber can be calculated by measuring the time difference between the previously generated time difference detection signal and the returned time difference detection signal.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 is a block diagram showing a configuration when Embodiment 1 of the present invention is used in a facing manner, in which 27 is a separation circuit attached to a receiving unit of the own station, and 35 is an own station. Light receiving circuit 4
The averaging circuit of the own station for averaging the current signal output by the device and outputting the average value signal, 36 is the first reference level generation of the own station for generating the reference signal corresponding to the output signal of the averaging circuit 35 of the own station A circuit, 37, compares the output signal of the averaging circuit 35 of the own station with the output signal of the first reference level generation circuit 36 of the own station, and outputs a voltage signal according to the difference, the first comparison of the own station. Reference numeral 38 is a circuit, 38 is a second reference level generation circuit of the own station that generates a reference signal corresponding to the gain level signal of the AGC amplification circuit 6 of the own station, and 39 is a gain level signal of the AGC amplification circuit 6 of the own station and the own station. Of the second reference level generating circuit 38 and outputs a voltage signal corresponding to the difference between the output signals of the second reference level generating circuit 38 and the second comparing circuit 40 of its own station, and 40 is the first comparing circuit 37 of its own station and that of its own station. Based on the output signal of the second comparison circuit 39, the optical output of the other station A control signal generation circuit of its own station for outputting a control signal for controlling, 29 is an averaging circuit 35 of its own station, a first reference level generation circuit 36 of its own station, a first comparison circuit 37 of its own station, A control signal generation unit of the station, which includes a second reference level generation circuit 38 of the station, a second comparison circuit 39 of the station, and a control signal generation circuit 40 of the station, and 41 is a separation associated with the reception unit of the station. The control signal restoration circuit of the own station for restoring the control signal which is one of the output signals of the circuit 27, 42 is the modulation in the optical output drive circuit 12 of the own station based on the output signal of the control signal restoration circuit 41 of the own station A modulation current drive circuit of its own station for driving a current, 43 is a bias current drive circuit of its own station for driving a bias current in the optical output drive circuit 12 of its own station based on the output signal of the control signal restoration circuit 41 of its own station , 28 is the control signal restoration circuit 41 of the own station, Adjusting the current drive circuit 4
2, a control signal processing unit of the own station including the bias current drive circuit 43 of the own station, 30 a multiplexing circuit associated with the transmission unit of the own station, 31 a separation circuit associated with the reception unit of the other station, and 35 the other station The control signal generator of the partner station, which generates a control signal based on the output signal of the receiver 15 of FIG. 1, restores the control signal which is one of the output signals of the separation circuit 31 attached to the receiver of the partner station. The control signal restoration circuit of the partner station, 47 is the modulation current drive circuit of the partner station that drives the modulation current in the optical output drive circuit 44 of the partner station based on the output signal of the control signal restoration circuit 46 of the partner station, and 48 is the partner Station control signal restoration circuit 4
A bias current drive circuit of the partner station for driving the bias current in the optical output drive circuit 44 of the partner station based on the output signal of 6; 32, a control signal restoration circuit 46 of the partner station; a modulation current drive circuit 47 of the partner station, The control signal processing unit of the partner station, which is composed of the bias current drive circuit 48 of the partner station, and 34 is a multiplexing circuit attached to the transmitter of the partner station.

Next, the operation will be described. First, the control signal generation unit 29 of its own station will be described. As described above with respect to the temperature characteristic diagram of the photoelectric conversion efficiency of the laser diode of FIG. 5, since the threshold current and the differential quantum efficiency of the laser diode change with the temperature change of the surroundings, the average light output and the maximum value emitted from the laser diode are increased. In order to keep the light output constant, the bias current and the modulation current have to be increased or decreased according to the temperature variation. Therefore, the same potential as the average potential obtained by averaging the light receiving element current of the light receiving circuit 4 of the own station by the averaging circuit 35 of the own station in the state where the desired average light output is obtained 1 is generated by the reference level generating circuit 36 of the first station, and the output potential of the averaging circuit 35 of the own station in a certain state and the output potential of the first reference level generating circuit 36 of the own station are the first potential of the own station. The comparison circuit 37 compares the magnitude relationship. Also, when the target maximum optical output is obtained, the AG
The same potential as the gain level of the C amplification circuit 6 is generated by the second reference level generation circuit 38 of the own station, and the gain level of the AGC amplification circuit 6 of the own station in a certain state and the second reference level of the own station are generated. The output potential of the level generation circuit 38 is compared by the second comparison circuit 39 of its own station in terms of their magnitude relationship.
Next, the control signal generation circuit 40 of the own station generates a control signal based on the outputs of the first comparison circuit 37 of the own station and the second comparison circuit 39 of the own station. If the output potential of the first reference level generation circuit 36 of the own station exceeds the output potential of the averaging circuit 35 of the own station because the average optical output does not reach the target level in the control signal, the other party Information is given to increase the bias current in the optical output drive circuit 44 of the station, and conversely, since the average optical output exceeds the target level, the output potential of the averaging circuit 35 of the own station is the same as that of the own station. When the output potential of the reference level generating circuit 36 of 1 is exceeded, information is given to reduce the bias current in the optical output drive circuit 44 of the other station, and if the average optical output is the target level, the current bias current is obtained. To have information that keeps If the maximum optical output does not reach the target level,
If the output potential of the reference level generation circuit 38 of is higher than the gain level of the AGC amplifier circuit 6 of the own station, information to increase the modulation current in the optical output drive circuit 44 of the other station is added, and vice versa. When the gain level of the AGC amplifier circuit 6 of the own station exceeds the output potential of the second reference level generating circuit 38 of the own station because the maximum optical output exceeds the target level, the optical output drive circuit of the other station Information for reducing the modulation current at 44 is provided, and information for maintaining the current modulation current is provided if the maximum optical output is the target level.

The generated control signal is multiplexed with the data signal from the data input terminal 18 of the own station by the multiplexing circuit 30 attached to the transmitter of the own station, and the transmitter 14 of the own station transmits the electric signal as an optical signal. And is transmitted to the receiving unit 15 of the partner station via the optical fiber 3. The optical signal transmitted to the receiving unit 15 of the partner station is converted into an electric signal by the receiving unit 15 of the partner station, and the same optical signal as the output signal of the multiplexing circuit 30 attached to the transmitter of the own station is first multiplexed. The signal is played back. The reproduced multiplexed signal is separated into a data signal and a control signal by the separation circuit 31 of the partner station, and the data signal is the data output terminal 19 of the partner station.
And the control signal is transmitted to the control signal processing unit 32 of the partner station. The control signal is restored by the control signal restoration circuit 46 of the partner station into information relating to the control of the bias current and information relating to the control of the modulation current, and the bias current drive circuit 48 of the partner station and the modulation current drive circuit of the partner station are restored by the respective information. Via 47, the bias current and the modulation current in the optical output drive circuit 44 of the partner station are controlled. By the above processing, the light emitting circuit 45 of the partner station is controlled so that the optimum bias current and modulation current always flow, so that the optical signal from the partner station 2 can always be kept in a desired state. Further, similarly to the above description, by controlling the transmitter 14 of the own station by the partner station 2, the optical signal from the own station 1 can always be kept in a target state.

Embodiment 2 FIG. 2 is a block diagram showing a configuration when Embodiment 2 of the present invention is used in a facing manner, in which 49 is the peak value of the output signal of the AGC amplifier circuit 6 of its own station. It is an AC component detection circuit of its own station that detects and outputs a DC voltage signal. In the first embodiment, the gain level of the AGC amplifier circuit 6 of its own station is used to control the modulation current. However, in the second embodiment, the amplification level of the AGC amplifier circuit 6 of its own station is linear in the middle stage of the amplifier. The amplified signal wave was taken out, and the amplitude component of the AC component of the amplified signal wave was converted into a voltage signal by the AC component detection circuit 49 of its own station. In the method of the first embodiment, the gain level changes with respect to the fluctuation of the amplitude of the input signal, but the change amount is small and a control error is likely to occur. However, the method of the second embodiment produces a large amplified wave to some extent. Since it is used, the control error can be reduced.

Third Embodiment FIG. 3 is a block diagram showing a third embodiment of the present invention. In the figure, reference numeral 50 designates a time difference detection signal of its own station which outputs a time difference detection signal for obtaining a transmission time of an optical fiber. An output circuit, 51 is a time difference detection signal output circuit 50 of its own station, and a time difference detection signal detection circuit of its own station connected to the separation circuit 27 attached to the receiving section of its own station, and 52 is a time difference detection signal detection circuit 51 of its own station. The transmission distance calculation circuit of the own station, which calculates the transmission distance of the optical fiber based on the output from and outputs the voltage signal indicating the transmission distance, 53 is the output voltage signal of the time difference detection signal detection circuit 51 of the own station to the outside. The first detection signal output terminal of the own station for outputting, 54 is the second detection signal output terminal of the own station for outputting the output voltage signal of the transmission distance calculation circuit 52 of the own station to the outside. In the time difference detection signal issuing circuit 50 of the own station,
At a certain time T1, the multiplexing circuit 30 attached to the transmitter of the own station
And a time difference detection signal to the time difference detection signal detection circuit 51 of its own station. The time difference detection signal output to the multiplexing circuit 30 associated with the transmitter of the own station is the separation circuit 31 associated with the transmitter 14 of the own station, the optical fiber 3, the receiver 15 of the partner station, and the receiver of the partner station. Multiplexing circuit 34 associated with the transmitter of the partner station, transmitter 16 of the partner station, and optical fiber 3
And transmitted to the separation circuit 27 attached to the receiving unit of the own station through the receiving unit 9 of the own station. The time difference detection signal detection circuit 51 of the own station is separated from the separation circuit 27 attached to the receiving unit of the own station.
The time at which the time difference detection signal is output is T2. Next, in the time difference detection signal detection circuit 51 of the own station, time T1 when the time difference detection signal is input from the time difference detection signal issuing circuit 50 of the own station and the time difference detection of the own station from the separation circuit 27 attached to the receiving unit of the own station. At time T2 when the time difference detection signal is output to the signal detection circuit 51, the time for reciprocating the optical fiber 3 between the own station 1 and the partner station 2 is obtained, and the time difference signal is calculated by the transmission distance calculation circuit 52 of the own station. The signal is output to the first detection signal output terminal 53 of the own station. The transmission distance calculation circuit 52 of the own station calculates the transmission distance based on the time difference signal input from the time difference detection signal detection circuit 51 of the own station, and outputs a signal having information of the transmission distance to the second detection signal output terminal of the own station. To 54.

[0014]

According to the first aspect of the present invention, unlike the conventional method, the transmission section of the partner station does not control or compensate the optical output,
A control signal is generated on the receiving side of the own station using the voltage signal obtained by averaging the output current of the light receiving circuit of the own station and the gain level signal of the AGC amplifier circuit of the own station, and the control signal is multiplexed with the data signal. Then, by transmitting to the partner station and controlling the transmitter of the partner station based on the control signal in the partner station, it is not necessary to adjust the transmitter of the partner station according to the individual variations of the laser diode characteristics.

According to the second aspect of the invention, unlike the conventional method, the transmitting section of the partner station does not control and compensate the optical output, and the receiving section of the own station outputs the output of the light receiving circuit of the own station. A control signal is generated using the voltage signal obtained by averaging the current and the voltage signal obtained by detecting the AC component of the middle output of the AGC amplifier circuit of the own station, and the control signal is multiplexed with the data signal and transmitted to the other station, By controlling the transmitter of the partner station based on the control signal in the partner station, it becomes unnecessary to adjust the transmitter of the partner station according to the individual variation of the laser diode characteristics.

According to the third aspect of the invention, the local station transmits a data signal multiplexed with the time difference detection signal, and the partner station transmits the received time difference detection signal again without multiplexing with the data. At the station, the transmission distance of the fiber can be calculated by measuring the time difference between the time difference detection signal that has been emitted earlier and the time difference detection signal that has been returned.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of an optical transceiver according to the present invention.

FIG. 2 is a block diagram showing a second embodiment of an optical transceiver according to the present invention.

FIG. 3 is a block diagram showing a third embodiment of an optical transceiver according to the present invention.

FIG. 4 is a block diagram showing a conventional optical transceiver.

FIG. 5 is a temperature characteristic diagram of photoelectric conversion efficiency of a laser diode.

FIG. 6 is a laser diode drive circuit diagram in a conventional method.

[Explanation of symbols]

 1 Own station 2 Opposite station 3 Optical fiber 4 Light receiving circuit of own station 5 Preamplifier circuit of own station 6 AGC amplifier circuit of own station 7 Timing extraction circuit of own station 8 Identification and reproduction circuit of own station 9 Receiver section of own station 10 Optical output temperature compensation circuit of own station 11 Optical output control circuit of own station 12 Optical output drive circuit of own station 13 Light emitting circuit of own station 14 Transmitter of own station 15 Receiver of other station 16 Transmitter of other station 17 Data output terminal of own station 18 Data input terminal of own station 19 Data output terminal of partner station 20 Data input terminal of partner station 21 Laser diode module 22 Laser diode 23 Monitor photodiode 24 Smoothing capacitor 25 Average optical output reference voltage 26 Modulation Current temperature compensating temperature sensitive element 27 Separation circuit attached to receiving section of own station 28 Control signal processing section of own station 29 Control signal generating section of own station 30 Multiplexing Circuit Associated with Transmitting Section of Own Station 31 Separation Circuit Associated with Receiving Section of Other Station 32 Control Signal Processing Section of Other Station 33 Control Signal Generating Section of Other Station 34 Multiplexing Circuit Associated with Transmission Section of Other Station 35 Averaging circuit of own station 36 First reference level generating circuit of own station 37 First comparing circuit of own station 38 Second reference level generating circuit of own station 39 Second comparing circuit of own station 40 Own station Control signal generation circuit 41 Control signal restoration circuit of own station 42 Modulation current drive circuit of own station 43 Bias current drive circuit of own station 44 Optical output drive circuit of partner station 45 Light emission circuit of partner station 46 Control signal restoration circuit of partner station 47 Modulation current drive circuit of partner station 48 Bias current drive circuit of partner station 49 AC component detection circuit of own station 50 Time difference detection signal issuing circuit of own station 51 Time difference detection signal detection circuit of own station 52 The second detection signal output terminal of the feed distance calculating circuit 53 first detection signal output terminal 54 the mobile station of its own station

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H04B 10/26

Claims (3)

[Claims] 1. A light receiving circuit for outputting a current signal of an optical signal obtained by superimposing a control signal on a data signal input from an optical fiber, the current signal being connected to the light receiving circuit,
A preamplifier circuit that converts the current signal into a voltage signal; an AGC amplifier circuit that amplifies the voltage signal to a desired amplitude;
A timing extraction circuit that extracts a clock component from the output signal of the AGC amplifier circuit, and an output signal of the AGC amplifier circuit that is discriminated and reproduced based on the output signal of the timing extraction circuit to output a data signal including a control signal and a clock signal. Identification reproduction circuit, a separation circuit for separating a data signal and a control signal, a data output terminal for outputting the data signal from the separation circuit to the outside, and the optical output drive based on the control signal from the separation circuit A control signal processing unit that outputs a bias current control signal and a modulation current control signal of the circuit, an averaging circuit that averages the current signals output by the light receiving circuit and outputs an average value signal, and an output signal of the averaging circuit And a second reference level generation circuit for generating a reference signal corresponding to the gain level signal of the AGC amplifier circuit. A reference level generation circuit, a first comparison circuit that compares the output signal of the averaging circuit and the output signal of the first reference level generation circuit, and outputs a voltage signal corresponding to the difference, and the AGC amplification circuit. Of the first comparison circuit and the second comparison circuit, which compares the gain level signal of 1) with the output signal of the second reference level generation circuit and outputs a voltage signal corresponding to the difference between the gain level signal and the output signal of the second reference level generation circuit. A control signal generation circuit that outputs a control signal for controlling the optical output of the other station based on the output signal, a data input terminal that inputs a data signal from the outside, a control signal that the control signal generation circuit outputs, and A multiplexing circuit that multiplexes data signals from data input terminals, an optical output driving circuit that operates according to an output signal of the multiplexing circuit and an output signal of the control signal processing unit, and an output signal of the optical output driving circuit Optical transceiver being characterized in that a light-emitting circuit for output to the optical fiber a light signal corresponding. 2. A light receiving circuit for outputting a current signal of an optical signal obtained by superimposing a control signal on a data signal input from an optical fiber, the current signal being connected to the light receiving circuit,
A preamplifier circuit that converts the current signal into a voltage signal; an AGC amplifier circuit that amplifies the voltage signal to a desired amplitude;
A timing extraction circuit that extracts a clock component from the output signal of the AGC amplifier circuit, and an output signal of the AGC amplifier circuit that is discriminated and reproduced based on the output signal of the timing extraction circuit to output a data signal including a control signal and a clock signal. Identification reproduction circuit, a separation circuit for separating a data signal and a control signal, a data output terminal for outputting the data signal from the separation circuit to the outside, and the optical output drive based on the control signal from the separation circuit A control signal processing unit for outputting a bias current control signal and a modulation current control signal for the circuit, an averaging circuit for averaging the current signals output by the light receiving circuit and outputting an average value signal, and an output signal for the AGC amplifier circuit. Component detecting circuit for detecting the peak value of the signal and outputting a DC voltage signal, and a first reference for generating a reference signal corresponding to the output signal of the averaging circuit A bell generation circuit, a second reference level generation circuit that generates a reference signal corresponding to the output signal of the AC component detection circuit, an output signal of the averaging circuit, and an output signal of the first reference level generation circuit. Comparing the output signals of the AGC amplifier circuit and the output signal of the second reference level generating circuit, and outputting a voltage signal corresponding to the difference between them. And a control signal generation circuit for outputting a control signal for controlling the optical output of the partner station based on the output signals of the first comparison circuit and the second comparison circuit, and data. A data input terminal for inputting a signal from the outside, a multiplexing circuit for multiplexing the control signal output by the control signal generating circuit and the data signal from the data input terminal, an output signal of the multiplexing circuit, and the control signal processing unit. And an optical output drive circuit which operates in response to the output signal, the optical transceiver being characterized in that a light-emitting circuit for output to the optical fiber a light signal corresponding to the output signal of the light output drive circuit. 3. A time difference detection signal issuing circuit for outputting a time difference detection signal for obtaining a transmission time of an optical fiber, a data input terminal for externally inputting a data signal, and a time difference detection output by the time difference detection signal issuing circuit. A multiplexing circuit for multiplexing a signal and a data signal from the data input terminal;
A transmitting unit that outputs the output signal of the multiplexing circuit to the optical fiber as an optical signal, a receiving unit that converts the optical signal input from the optical fiber in which the data signal and the time difference detection signal are multiplexed into an electric signal, and the data signal, A separation circuit for separating the time difference detection signal, a data output terminal for outputting the data signal from the separation circuit to the outside, a time difference detection signal output from the time difference detection signal issuing circuit, and a time difference detection output from the separation circuit A time difference detection signal detection circuit that compares signals and outputs a voltage signal that represents the time difference, and calculates the transmission distance of the optical fiber based on the output from the time difference detection signal detection circuit, and outputs the voltage signal that represents the transmission distance. A transmission distance calculation circuit, a first detection signal output terminal for outputting an output voltage signal of the time difference detection signal detection circuit to the outside, and a transmission distance calculation circuit Optical transceiver being characterized in that a second detection signal output terminal for outputting a power voltage signal to the outside.