KR101245854B1 - apparatus and method of processing optical signal in optical communication system - Google Patents

Abstract

According to the present invention, an all-optical converter converts the generated first electrical signal, and outputs a third signal including a non-linearly generated second signal, and branches the first signal from the front end of the all-optical converter. A distortion canceller for inverting the phase of one signal, totally converting and receiving the third signal, and combining the first signal and the third signal to generate and invert the second signal, and generating an inverted second signal; And a third signal received from the converter and an inverted second signal received from the distortion canceller to remove the second signal, and then output the first signal to the optical line. Disclosed is an apparatus for effectively eliminating distortion due to nonlinear components in an optical communication system.

Description

Apparatus and method of processing optical signal in optical communication system

1 is a diagram for explaining the configuration of a general optical communication system.

2 is a block diagram illustrating a general predistortion optical communication system.

3 is a block diagram illustrating an optical communication system according to a preferred embodiment of the present invention.

4 is a view for explaining in more detail the optical communication system according to a preferred embodiment of the present invention.

5 is a graph illustrating distortion component suppression characteristics according to an operating current value of a main light emitting unit and a gain value of an amplifying unit according to the present invention;

6 is a graph illustrating suppression characteristics of a main signal according to a gain value of a first amplifier.

7 is a graph illustrating distortion component suppression characteristics according to gain values of a second amplifier.

8 is a graph showing distortion component suppression characteristics according to a phase of a main signal.

9 is a flowchart for explaining an optical signal processing method of an optical communication system according to a preferred embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: all-optical conversion unit 200: output unit

300: distortion canceller 400: control unit

LD: Light emitting part C: Coupler part

OC: optocoupler unit D: delay signal generator

V; Signal Adjuster F: Transmitter

G: Amplifier

The present invention relates to an optical signal processing method and apparatus therefor of an optical communication system.

In general, optical communication means transmitting / receiving information through optical fiber as a medium.

1 is a view for explaining the configuration of a general optical communication system.

As shown in FIG. 1, the optical communication system includes a transmitter 10, a transmitter 20, and a receiver 30.

The transmitter 10 is implemented by combining an all-optical conversion element that converts an electrical signal to transmit information into an optical signal, that is, a laser diode, a light emitting diode, or a laser diode, which is a light source, and a modulator.

The receiver 30 includes an all-optical conversion element that converts an optical signal into an electrical signal, that is, a PN photodiode, a PIN photodiode, an avalanche photodiode, a phototransistor, or the like as a photodetector. do.

And, the optical fiber is used for the transmission unit 20 that is a medium for transmitting the optical signal.

Such a general optical communication system uses an analog subcarrier multiplexing method that directly modulates and demodulates a plurality of RF signals simultaneously to a light source, and a disadvantage of the analog subcarrier multiplexing method is that an analog signal is transmitted from a transmitter 10 to a receiver ( The distortion occurs due to the non-linearity of the medium in the optical fiber, which is the optical path transmitted to 30).

과

와 같은 형태의 새로운 주파수를 갖는 비선형 성분이 발생되는 것이다.Nonlinear distortion components generated in the optical communication system are referred to as intermodulation distortion (IMD), and are used in all-optical modulation of the all-optical conversion element in the transmitter 10 or in the optical path when the optical signal is transmitted over a long distance in the transmitter 20. By the propagation characteristics of

and

A nonlinear component with a new frequency of the form

This nonlinear component distorts the analog signal, which is an optical signal, and degrades the performance of the optical communication system within the transmission bandwidth. In particular, the light source of the transmitter 10 causes a lot of limitations in the intermodulation (IM) and dynamic range of the optical transmission system.

In order to solve distortion caused by nonlinear components in an optical communication system, a pre-distortion method has been proposed.

2 is a block diagram illustrating a general predistortion optical communication system.

Referring to FIG. 2, a first coupling part 1 for branching an electrical signal, that is, an undistorted signal, in front of the transmitter 10, a phase adjuster 2 for inverting a phase of the branched electric signal, and an electrical A harmonic generation unit 3 for generating a distortion signal that may occur in the signal, a delay unit 4 for delaying transmission of the branched electrical signal by a predetermined time, an electrical signal output from the delay unit 4, and a distortion signal It includes a second coupler unit 5 to combine and output to the transmission unit 20.

That is, the predistortion method is a method of solving distortion caused by nonlinear components by generating a distortion signal having the same magnitude and opposite phase as a signal that may be distorted by an electrical signal.

However, such a predistortion method has low efficiency compared to the price of the device to be implemented, and a high efficiency all-optical conversion device, for example, a high efficiency laser diode is required, but there is a limitation in manufacturing a high efficiency laser diode.

In addition, since the predistortion method has a linearization degree of 7 to 10 decibels (dB), the new method for solving the problem of nonlinear distortion in an optical communication system is urgent.

Accordingly, an object of the present invention is to provide an optical signal processing method and apparatus for an optical communication system that can effectively eliminate distortion due to nonlinear components in an optical communication system. have.

The optical signal processing apparatus of the optical communication system according to an aspect of the present invention for achieving the above object is to convert the first electrical signal generated by the whole optical conversion, the third signal including a non-linearly generated second signal An all-optical converter for outputting and branching the first signal at the front end of the all-optical converter, inverting the phase of the first signal, receiving and converting the third signal by all-optical conversion, combining the first signal and the third signal, and After the second signal is removed by combining the distortion canceller for generating and inverting the signal and generating the inverted second signal, the third signal received from the all-optical converter, and the inverted second signal received from the distortion canceller, An output unit for outputting the first signal to the optical line.

The distortion canceling unit according to the present invention inverts the phase of the first signal, receives the third signal that is totally converted by the all-optical conversion unit, and removes the first signal from the third signal, thereby generating a second signal. And a distortion processor for inverting the second signal generated by the distortion signal generator, converting the inverted second signal into an optical unit, and transmitting the converted second signal to the output unit.

The distortion signal generating unit according to the present invention includes a first coupling unit which is located at the front end of the all-optical conversion unit and branches the first signal, a first delayed signal generator which transmits and delays the branched first signal for a predetermined time period, and the transmission unit. A first signal adjusting unit for inverting the phase of the delayed first signal and adjusting an amplitude, a first optical coupler for branching the third signal converted by the all-optical conversion unit, and an all-optical conversion of the branched third signal A light receiving unit, a first amplifying unit amplifying the third signal received by the light receiving unit at a predetermined ratio, a third signal output from the first amplifying unit, and a first signal whose phase is adjusted by the first signal adjusting unit And a second coupler unit which removes the first signal and outputs a second signal.

The distortion processing unit according to the present invention includes a second signal adjusting unit for inverting a phase of the second signal and adjusting an amplitude, a second delay signal generator for delaying transmission of the inverted second signal for a predetermined time, and an inverted second signal. It includes an auxiliary light-emitting unit that transmits an optical signal to the output unit by converting the light.

The optical signal processing apparatus of the optical communication system according to the present invention stores the adjustment value according to the transmission distance of the first signal or the characteristic of each element constituting the distortion canceller, and the signal phase shift and amplitude of the distortion canceller according to the adjustment value. Or a control unit for controlling amplification.

The control unit according to the present invention includes a memory for storing the adjustment value according to the transmission distance of the first signal as a look-up table, or storing the adjustment value according to the characteristics of each device, and reading the adjustment value from the memory to determine each of the distortion canceling units. It includes a microprocessor for controlling the device.

The characteristic of each element according to the present invention is any one or more of the gain value of each amplification part, the operation rectification value of the all-optical conversion part, or the phase value of each signal.

An optical signal processing method of an optical communication system according to another aspect of the present invention comprises the steps of: branching the generated electrical first signal, and outputting a third signal including the second signal by totally converting the branched first signal; Inverting the phase of the branched first signal, totally converting and receiving the third signal, and combining and inverting the first signal and the third signal to generate and invert the second signal; And combining the three signals and the inverted second signal to output the first signal from which the second signal is removed to the optical line.

Hereinafter, an optical signal processing method and apparatus thereof for an optical communication system according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram illustrating an optical communication system according to a preferred embodiment of the present invention.

Referring to FIG. 3, the non-distorted electrical signal, that is, the all-optical converting unit 100 for all-optically converting the main signal, the main signal is branched, the phase of the branched main signal is inverted, and the all-optical converting unit 100 The distortion canceling unit 300 and the distortion canceling unit 300 which generate the inverted distortion signal after removing the main signal by combining the main + distortion signal and the inverted main signal by removing the main signal while being converted. The output unit 200 which combines the inverted distortion signal and the main + distortion signal to cancel the distortion signal and outputs only the main signal, and the characteristics of each element implementing the distortion cancellation unit 300 and between the transmitter and the receiver in the optical communication system. It includes a control unit 400 for controlling the distortion canceller 300 according to the transmission distance.

In addition, the all-optical converter 100 and the output unit 200 may be connected to the same optical line as the transmitter.

4 is a view for explaining in more detail the optical communication system according to an embodiment of the present invention.

Referring to FIG. 4, the all-optical converting unit 100 is implemented as an all-light changing element such as a laser diode, a light emitting diode, or a laser diode. Hereinafter, the detailed description of the present invention will be described with respect to the case of the laser diode LD1. A main + distortion signal including a distortion signal generated by a nonlinear distortion phenomenon is output to the signal transmission unit F1 while all-optical conversion of the main signal.

The distortion canceling unit 300 may include a first coupling unit C1, a first optical coupling unit OC1, an auxiliary light receiving unit PD, a first amplifier G1, a first delay signal generation unit D1, and a first coupling unit C1. The first signal adjusting unit V1, the second coupling unit C2, the second delay signal generating unit D2, the second signal adjusting unit V2, the second amplifier G2, the auxiliary light emitting unit LD2, and the second light A coupling part OC2, a first amplifying part G1, and a second amplifying part G2 are included.

The controller 400 controls the first and second signal adjusting units V1 and V2 based on the data provided from the memory 410 and the data provided from the memory 410 so that the optimized distortion cancellation is performed. The microprocessor 420 and the digital control signal received from the microprocessor 420 are converted into analog control signals, and the respective signal adjusting units V1 and V2, the delay signal generating units D1 and D2 and the respective amplifying units ( And a plurality of D / A converters 430 for transmitting to G1 and G2.

The first coupling unit C1 is positioned in front of the laser diode LD1 that is the all-optical converting unit 100, and branches the main signal. The coupler is a passive element for branching or combining electrical signals, and it is preferable to use a coupler having characteristics that operate well in the frequency band of the main signal.

The main signal branched from the first coupling unit C1 is input to the laser diode LD1 and the first delay signal generation unit D1, respectively.

The laser diode LD1 converts a main signal branched from the first coupling unit C1 into an optical signal, and transmits a main signal and a main + distortion signal including the main signal and the distortion signal generated by the nonlinear distortion phenomenon of the all-optical conversion. Output to (F1).

The first optical coupling unit OC1 is optically connected to the laser diode LD1, and the main + distortion signal output from the laser diode LD1 is transmitted to the main signal transmitter F1 and the auxiliary light receiver PD. Branch to input.

Since the optical coupler used in the first optical coupling part OC1 is a passive element that splits or couples an optical signal, and the main signal transmission part F1 is an optical fiber used as an optical line, it is preferable to use an optical fiber type coupler. desirable.

The auxiliary light receiving unit PD is an all-optical converting means for converting the main + distortion signal output from the laser diode LD1 into an electrical signal. A PN photodiode, a PIN photodiode, an Avalanche photodiode, a phototransistor, or the like may be used. Can be.

The first amplifier G1 amplifies the main + distortion signal converted into the electrical signal by the auxiliary light receiver PD at a predetermined ratio.

In this case, the amplification ratio of the first amplifier G1 may have the same magnitude as that of the main signal delayed by the first delay signal generator D1 and the main signal of the main + distortion signal input from the auxiliary light receiver PD. It is a ratio. That is, the first amplifier G1 amplifies the main + distortion signal by a predetermined ratio, and outputs a main + distortion signal having the same magnitude as the output main signal of the first delayed signal generator D1. do.

The first delay signal generator D1 delays the main signal by a predetermined time.

The first delay signal generator D1 performs a total light conversion by the laser diode LD1 and a second light receiver PD in order to remove the main signal from the main + distortion signal that is totally converted by the auxiliary light receiver PD. The sum of the time for conversion, the time for amplifying the signal by the first amplifier G1, the time for which the main signal is branched from the first coupling unit C1, and the transmission delay in the first delay signal generator D1. The transmission of the main signal is delayed so that the time obtained by matching the time obtained by adding the time adjusted by the first signal adjustment unit V1 to the same time is the same.

That is, the first delay signal generation unit D1 allows each main signal branched from the first coupling unit C1 to be applied to the second coupling unit C2 at the same time.

The first delay signal generator D1 may delay the signal transmission time using a cable type time delay line or a filter type time delay element.

The first signal adjuster V1 adjusts the phase and amplitude of the main signal received from the first delayed signal generator D1 under the control of the controller 400.

The first signal adjusting unit V1 may be implemented as a mechanical phase shifter or an electrical phase shifter to shift the phase of the main signal, and may be implemented as a mechanical attenuator or an electrical attenuator to attenuate the amplitude of the main signal. can do.

In other words, the first signal adjuster may include a main + distortion signal output from the auxiliary light receiver PD through a phase shift and amplitude attenuation of the main signal branched from the first coupling unit C1 to the first delay signal generator D1. With the same time delay, the phases are inverted and output the main signal with the same amplitude.

The second coupling part C2 includes a first amplifier G1 for amplifying the main + distortion signal output from the auxiliary light receiving part PD at a predetermined ratio, and a phase of the main signal delayed by the first delay signal generator D1. And a main signal electrically connected to the first signal adjusting unit V1 for adjusting the amplitude, having a same time delay and amplitude, having a phase difference of 180 degrees, and a main signal in the main + distortion signal, + Remove the main signal from the distortion signal and output only the distortion signal.

The main signal transmitter F1 is optically connected to the first optical coupling unit OC1 and transmits a main + distortion signal emitted from the laser diode LD1.

The second signal adjusting unit V2 is connected to the output terminal of the second coupling unit C2, and under the control of the control unit 400, phase shifts the distortion signal generated by the second coupling unit C2, and changes the amplitude. Attenuate / amplify and transmit the signal to the second delay signal generator D2. That is, the second signal adjusting unit inverts the phase of the distortion signal and adjusts the amplitude to be the same size as the distortion signal of the main + distortion signal transmitted to the main signal transmitting unit F1.

The second delay signal generator D2 delays the transmission time of the inverted distortion signal to synchronize the transmission time of the inverted distortion signal and the main + distortion signal.

The second amplifier amplifies the inverted distortion signal at a predetermined ratio and transmits the inverted distortion signal to the auxiliary light emitting unit, that is, the second laser diode LD2.

The second laser diode LD2 totally converts an inverted distortion signal, which is a received electrical signal, into an optical signal. That is, the second laser diode transmits a signal having the same time delay, 180 degree phase difference, and the same magnitude as that of the distortion signal component of the main + distortion signal transmitted through the main signal transmitter F1 to the second optical coupler unit OC2. send.

The all-optical conversion element used in the auxiliary light emitting part LD2 may use the same device as that of the all-light conversion element used in the main light emitting part LD1, or may use an element having the same wavelength. In order to prevent the beating phenomenon according to the light emission wavelength of the LD2 and the wavelength of the main light emitting part LD1, by increasing the wavelength difference between the main light emitting part LD1 and the auxiliary light emitting part LD2, It is desirable to spread the frequency.

The second optical coupling unit OC2 combines a main + distortion signal received through the main signal transmission unit F1 and an inverted distortion signal that is all-optically converted by the second laser diode LD2, thereby distorting the main + distortion signal. Cancel the signal.

The transmitter F2 is optically connected to the second optical coupling part OC2 and transmits the optical signal, that is, the main signal, coupled to the second optical coupling part OC2 to the receiving part.

As the transmission unit F2, an optical fiber cable is used. Due to the dispersion property of the optical fiber, the optical signal has a traveling speed depending on the wavelength, and this phenomenon changes the phase difference between the main signal and the distortion signal.

In addition, the change in the amount of attenuation according to the wavelength changes the magnitude difference between the main signal and the distortion signal, and in order to compensate for the changed phase difference and magnitude difference, the optical fiber length, the dispersion coefficient value, the attenuation constant value, and the main light emitting part The second signal adjusting unit V2 adjusts the magnitude and phase of the distortion signal in consideration of the wavelength difference between the LD1 and the auxiliary light emitting unit LD2.

The optical receiver is optically connected to the transmitter and converts an optical signal transmitted through the transmitter into an electrical signal.

The main signal and the distortion signal including the distortion signal respectively transmitted through the transmitter F2 are canceled with each other after being totally converted by the light receiving part of the receiver, and when converted by the light receiving part, the distortion signal of the main + distortion signal and the auxiliary light emitting part are cancelled. The distortion signal LD2 is adjusted by the second signal adjusting unit V2 to have a phase opposite to the same magnitude.

The feedforward technique according to the present invention uses the characteristics of the linearity improvement of the laser diode and has a wide dynamic range, but the system configuration is complicated and it is not easy to finely adjust the time delay, phase, and magnitude of each signal. Limitations may arise in the design and manufacture of values.

Accordingly, the controller 400 controls the adjustment of the phase and the magnitude of the first signal adjusting unit V1 and the second signal adjusting unit V2 of the transmitting unit of the optical communication system, and controls the first delay signal generating unit D1 and the second. Fine adjustment is performed by controlling the time delay of the delay signal generator D2.

Such a method of controlling the transmitter by the controller 400 includes a first method of controlling an adjustment value according to a change in distance of the transmitter F2 and a second method of controlling the characteristic value of each element constituting the transmitter. Can be distinguished.

First, the first method of controlling the adjustment value according to the change in the distance of the transmitter F2 will be described. In the memory 410 of the controller 400, the adjustment value (delay time value, A lookup table that stores a phase shift value or attenuation value, etc.).

That is, the memory 410 stores the adjustment value according to the length of the transmission unit F2, the dispersion coefficient value, and the wavelength difference between the main light emitting part KD1 and the auxiliary light emitting part LD2 as a lookup table.

The microprocessor 420 reads an adjustment value according to the distance of the transmission unit F2 from the lookup table stored in the memory 410, and according to the adjustment value, the first delay signal generator D1 and the second delay. By controlling the delay time of the signal generating unit D2 and finely controlling the phase shift and attenuation of the first signal adjusting unit V1 and the second signal adjusting unit V2, the degree of distortion component removal is constantly maintained regardless of the transmission distance. Keep it.

On the other hand, in the second method of controlling according to the characteristic value of each element constituting the transmitter, the control unit 400 controls the phase magnitude of the signal, the predetermined ratio (gain) of the first amplifier G1 and the second amplifier G2. Value), and an adjustment value according to the characteristic value of each device such as the operating current value of the main light emitting part LD1 is calculated and stored in the memory 410.

The microprocessor 420 controls the delay times of the first delay signal generator D1 and the second delay signal generator D2 according to the adjustment value stored in the memory 410, and the first signal controller (V1), the phase shift and attenuation of the second signal adjustment unit V2 are finely controlled.

5 is a graph illustrating distortion component suppression characteristics according to an operating current value of a main light emitting unit and a gain value of an amplifying unit according to the present invention.

As illustrated in FIG. 5, the distortion component suppressing component is different according to the gain value of the amplifier G1 and the operating current value of the main light emitting unit LD1, and thus, the amplifier G1 exhibiting the optimum distortion component suppressing characteristics. The main light emitting unit LD1 and the amplifying unit G1 are controlled by selecting a gain value and an operating current value of?) As adjustment values.

6 is a graph illustrating suppression characteristics of a main signal according to a gain value of a first amplifier.

As shown in FIG. 6, since the suppression characteristic of the main signal is different according to the gain value of the first amplifier G1, the gain value of the first amplifier G1 having the optimal suppression characteristic is selected as an adjustment value. To control the gain of the first amplifier G1.

7 is a graph illustrating distortion component suppression characteristics according to gain values of the second amplification unit.

As shown in FIG. 7, the distortion component suppression characteristic is different according to the gain value of the second amplifier G2, so that the gain value having the optimal distortion component suppression characteristic is selected as an adjustment value and the second amplifier G2 is selected. Control gain).

8 is a graph illustrating distortion component suppression characteristics according to a phase of a main signal.

Referring to FIG. 8, since the distortion component suppression characteristic is different according to the phase magnitude of the main signal, the phase magnitude of the main signal is controlled by selecting a phase magnitude value having an optimal distortion component suppression characteristic as an adjustment value.

9 is a flowchart illustrating an optical signal processing method of an optical communication system according to a preferred embodiment of the present invention.

Referring to FIG. 9, the transmitter of the optical communication system generates a main signal which is an electrical signal to be transmitted as an optical signal (S100).

Then, the transmitter branches the main signal, applies one branched signal to the main light emitting unit LD1, and applies the other signal to the first delayed signal generator D1 (S 110).

The main light emitting unit LD1 performs an all-optical conversion of the main signal, and the first optical coupler unit OC1 splits the all-converted main + distortion signal and outputs the main signal transmission unit F1 to the auxiliary light receiving unit PD. (S 120).

The auxiliary light receiving unit PD converts the main + distortion signal branched from the first optical coupler unit OC1 to the first amplifying unit G1 by all-optical conversion, and the first amplifying unit G1 performs main + distortion at a predetermined ratio. The signal is amplified and transmitted to the second coupler unit C2 (S130).

The first delayed signal generator D1 and the first signal adjuster V1 adjust the transmission delay, the phase shift, and the amplitude of the branched main signal, and transmit the branched main signal to the second coupler C2 (S 140). .

At this time, the control unit 400 reads the adjustment value according to the characteristic value of each element constituting the look-up table of the memory 410 or the transmission unit in which the adjustment value is stored according to the distance change of the transmission unit F2 and the first amplifier unit ( G1), the first delay signal generation unit D1 and the first signal adjustment unit V1 are finely controlled.

 The second coupler C2 combines the main + distortion signal and the main signal whose phase is inverted and outputs only the distortion signal to the second signal adjusting unit V2 (S 150).

The second signal adjusting unit inverts the phase of the received distortion signal and transmits it to the second delay signal generator D2. The second delay signal generator D2 delays the transmission of the inverted distortion signal to the second amplifier G2. (S 160).

At this time, the control unit 400 reads the adjustment value according to the characteristic value of each element constituting the look-up table of the memory 410 or the transmission unit in which the adjustment value is stored according to the distance change of the transmission unit F2 and the second amplifier unit ( G2), the second delay signal generation unit D2 and the second signal adjustment unit V2 are finely controlled.

The auxiliary light emitting unit LD2 converts the inverted distortion signal into an all-optical signal and transmits the inverted distortion signal to the second optical coupler unit OC2, and the second optical coupler unit OC2 is received through the main signal transmitter F1. The distortion signal and the inverted distortion signal are combined to cancel the distortion signal and output to the transmission unit F2 (S 170).

In the above-described detailed description of the present invention, a case in which the distortion component is removed by controlling the time delay, phase, and amplitude of the signal in accordance with the transmission distance of the optical signal and the characteristic values of the device in the transmitter of the optical communication system has been described. The same applies to the case of removing the predictable distortion component from.

As described above, according to the present invention, when the optical signal is output in the optical communication system, an inverted distortion signal is generated from a main + distortion signal including a main signal that is not all-optical converted and a distortion signal generated during all-optical conversion. Thereafter, the distortion signal is canceled and transmitted to the receiver, thereby stably removing the distortion signal.

And, by controlling the control unit to remove the distortion component in accordance with the transfer function and the characteristic that varies depending on the characteristic value of each element constituting the transmitter, it is possible to perform automatic fine control.

In addition, by controlling the control unit to remove the distortion component by the adjustment value according to the transmission distance of the optical signal, it is possible to transmit a stable and constant optical signal irrespective of the transmission distance.

Claims (8)

In the optical communication system, An all-optical conversion unit configured to all-optically convert the generated electrical first signal and to output a third signal including a second signal generated non-linearly; The first signal is branched from the front end of the all-optical converter, the phase of the first signal is inverted, the third signal is all-optically received, and the second signal is combined with the first and third signals. A distortion canceller for generating and inverting a signal and generating an inverted second signal; An output unit for combining the third signal received from the all-optical conversion unit with the inverted second signal received from the distortion canceling unit to remove the second signal, and then outputting the first signal to an optical line; A control unit for storing an adjustment value according to a transmission distance of the first signal or a characteristic of each element constituting the distortion canceller, and controlling a signal phase shift, amplitude or amplification of the distortion canceller according to the adjustment value Optical signal processing device in a communication system. The method of claim 1, wherein the distortion canceling unit, A distortion signal generation unit for inverting the phase of the first signal, receiving the third signal that is totally converted by the all-optical conversion unit, and generating the second signal after removing the first signal from the third signal. Wow, And a distortion processing unit for inverting the second signal generated by the distortion signal generator and converting the inverted second signal into an all-optical signal and transmitting the converted second signal to the output unit. The method of claim 2, wherein the distortion signal generation unit, A first coupling part positioned in front of the all-optical conversion part and branching the first signal; A first delay signal generation unit configured to delay transmission of the branched first signal for a predetermined time; A first signal adjusting unit for inverting a phase of the transmission delayed first signal and adjusting an amplitude; A first optical coupler unit for branching the third signal converted by the all-optical conversion unit; A light receiving unit which totally converts and receives the branched third signal; A first amplifier which amplifies the third signal received by the light receiver at a predetermined ratio; And a second coupler unit configured to remove the first signal by combining the third signal output from the first amplifier and the first signal whose phase is adjusted by the first signal adjuster to output the second signal. Optical signal processing device of the optical communication system. The method of claim 2, wherein the distortion processing unit, A second signal adjusting unit for inverting a phase of the second signal and adjusting an amplitude; A second delay signal generation unit configured to delay transmission of the inverted second signal for a predetermined time; And an auxiliary light emitting unit configured to totally convert the inverted second signal to transmit an optical signal to an output unit. delete The method of claim 1, wherein the control unit, A memory for storing an adjustment value according to a transmission distance of the first signal as a look-up table or storing an adjustment value according to a characteristic of each device; And a microprocessor that reads the adjustment value from the memory and controls each element of the distortion canceller. The method of claim 6, wherein the characteristics of each device, The optical signal processing apparatus of the optical communication system which is any one or more of the gain value of each amplification part, the operation rectification value of the all-optical conversion part, or the phase value of each signal. delete

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