WO2018094574A1

WO2018094574A1 - Dispersion compensation method and apparatus

Info

Publication number: WO2018094574A1
Application number: PCT/CN2016/106812
Authority: WO
Inventors: 张亮; 周杰; 左天健
Original assignee: 华为技术有限公司
Priority date: 2016-11-22
Filing date: 2016-11-22
Publication date: 2018-05-31
Also published as: CN109983718A; CN109983718B

Abstract

A dispersion compensation method and apparatus, used for compensating dispersion in an optical fibre communication system. The method comprises: a receiving end of an optical fibre communication system determining a one-to-one correlation between a plurality of optimal phase compensation values and a plurality of sub-carrier signals in a first multi-carrier signal to be transmitted by a transmission end of the optical fibre communication system; the receiving end generating indication information, the indication information comprising the one-to-one correlation between the plurality of optimal phase compensation values and the plurality of sub-carrier signals in the first multi-carrier signal; the receiving end sending the generated indication information to the transmission end; the transmission end receiving the indication information sent by the receiving end, and according to the one-to-one correlation, using the plurality of optimal phase compensation values to perform phase compensation on the plurality of sub-carrier signals in the first multi-carrier signal so as to obtain a second multi-carrier signal; the transmission end performing optical modulation on the second multi-carrier signal so as to obtain a first optical signal; and the transmission end sending the first optical signal to the receiving end.

Description

Dispersion compensation method and device

Technical field

The present invention relates to the field of optical fiber communication technologies, and in particular, to a dispersion compensation method and apparatus.

Background technique

With the continuous development of mobile internet technology, optical fiber communication systems are widely used in signal transmission processes due to their high speed and large capacity. The problem of dispersion of optical signals in fiber optic links has been a major problem that constrains the performance of fiber-optic communication systems.

In order to solve the problem of dispersion of the optical signal in the optical fiber link, in the prior art, the transmitting end performs dispersion compensation on the signal to be transmitted according to the estimated dispersion value, and transmits the dispersion-compensated signal to the receiving end to reduce the light received by the receiving end. The degree of dispersion of the signal. For example, suppose the dispersion expression is H(w) and the transmitter signal is Txwave. When performing dispersion compensation, the inverse function 1/H(w) of the dispersion expression is usually superimposed on the signal to be transmitted, then the dispersion compensation is added. The signal to be transmitted is: Txwave_comp=IFFT(FFT(Txwave)/H(w)), where FFT represents Fast Fourier Transformation (FFT) and IFFT represents Inverse Fast Fourier Transform (Inverse Fast Fourier Transform, IFFT).

In the existing technical solution for performing dispersion compensation on the dispersion in the optical fiber link, since the dispersion value of the dispersion compensation of the signal to be transmitted at the transmitting end is estimated, factors such as the type, length and phase noise of the optical fiber link will be practical. The dispersion value of the dispersion compensation should be affected. Therefore, the dispersion of the signal to be transmitted is only compensated by the estimated dispersion value under the premise that the above various factors are unknown, and the dispersion in the fiber link cannot be accurately compensated.

In summary, the existing technical solution for dispersion compensation of dispersion in a fiber link has a problem that the dispersion compensation value is inaccurate.

Summary of the invention

In view of this, a dispersion compensation method and device are provided for implementing a compensation optical fiber communication system Dispersion in the middle.

In a first aspect, an embodiment of the present invention provides a dispersion compensation method, where the method includes:

The transmitting end of the optical fiber communication system receives the indication information sent by the receiving end of the optical fiber communication system, and the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end. The transmitting end performs phase compensation on the plurality of subcarrier signals by using a plurality of optimal phase compensation values according to the one-to-one correspondence relationship to obtain a second multicarrier signal; and the transmitting end optically modulates the second multicarrier signal to obtain the first The optical signal transmits the first optical signal to the receiving end.

In the above first aspect, the one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end means that for each subcarrier in the first multicarrier signal In terms of the signal, there is a unique optimal phase compensation value corresponding to the subcarrier signal, and the optimal phase compensation value is used for phase compensation of the subcarrier signal, the number of the plurality of optimal compensation values and the plurality of subcarrier signals The number is the same.

With the above solution, the indication information sent by the receiving end to the transmitting end includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end, and the transmitting end includes the indication information according to the indication information. The one-to-one correspondence uses a plurality of optimal phase compensation values to phase compensate a plurality of subcarrier signals in the first multicarrier signal. Since the transmitting end performs dispersion compensation on the first multi-carrier signal, a plurality of optimal phase compensation values are used according to a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multi-carrier signal. For performing dispersion compensation on a plurality of subcarrier signals in the first multicarrier signal, compared with the prior art using a dispersion expression to compensate a signal to be transmitted at a transmitting end, the method provided by the first aspect is directed to the first multicarrier Each subcarrier signal in the signal is separately compensated, and thus the dispersion compensation is more accurate.

In a possible design, before the transmitting end receives the indication information sent by the receiving end, the following operations may also be performed, so that the receiving end can determine the one-to-one correspondence:

The transmitting end determines a plurality of preset phase compensation values; the transmitting end respectively performs the following operations on the first multi-carrier signal by using each of the preset phase compensation values: using the preset phase compensation value to the first Phase compensation for each subcarrier signal in the multicarrier signal to obtain a third multicarrier a signal; optically modulating the third multi-carrier signal to obtain a second optical signal, and transmitting the second optical signal to the receiving end, where the second optical signal is used by the receiving end according to the performance of the plurality of sub-carrier signals included in the second optical signal The indicator value determines the one-to-one correspondence.

The performance indicator values of the plurality of subcarrier signals included in the second optical signal include, but are not limited to, a signal to noise ratio SNR and/or a bit error rate BER.

For any one of the first multicarrier signals, the optimum phase compensation value is set as follows:

When the performance indicator value includes the SNR, the preset phase compensation value used when the SNR of the subcarrier signal in the plurality of second optical signals is maximum is the optimal phase compensation value corresponding to the subcarrier signal;

When the performance indicator value includes the BER, the preset phase compensation value used when the BER of the subcarrier signal in the plurality of second optical signals is minimum is the optimal phase compensation value corresponding to the subcarrier signal.

According to the above solution, the plurality of optimal phase compensation values are based on the phase compensation test of the first multi-carrier signal by using a plurality of preset phase compensation values respectively at the transmitting end, and the receiving end is configured according to each of the second optical signals. The performance value of the plurality of subcarrier signals included in the second optical signal is determined. Since multiple optimal phase compensation values are factors influencing dispersion compensation in fiber-optic communication systems (eg, transmission distance, nonlinear factors and quantization noise of each device in the transmitting end, noise in the fiber link, etc.) are taken into consideration Thereafter, the receiving end determines the performance index value of the plurality of subcarrier signals included in each of the second optical signals, and thus may perform the phase compensated first multicarrier signal (ie, the second multicarrier The performance index value of the signal is better, and the performance index value of the first optical signal obtained by the second multi-carrier signal is also better.

In a possible design, each of the preset phase compensation values is located in the same setting interval; when the plurality of preset phase compensation values are arranged in numerical order, multiple pre- Let the difference between any two adjacent phase compensation values in the phase compensation value be the preset step size.

According to the above scheme, each preset phase compensation value is set in the set interval, and the preset setting of the preset phase compensation value can be avoided; at the same time, the plurality of preset phase compensation values are evenly distributed evenly within the set interval. The distribution is such that the plurality of optimal phase compensation values are selected more accurately, so that the dispersion compensation effect is better.

In a possible design, the second multicarrier signal may also be inverse Fourier transformed before the transmitting end optically modulates the second multicarrier signal. The second multicarrier signal in the frequency domain is thereby converted into a second multicarrier signal in the time domain. Converting the second multi-carrier signal in the frequency domain into the second multi-carrier signal in the time domain and then performing optical modulation is easier to implement.

In a second aspect, an embodiment of the present invention provides a dispersion compensation method, which includes: determining, by a receiving end of an optical fiber communication system, a plurality of optimal phase compensation values and a plurality of first multi-carrier signals to be transmitted by a transmitting end of the optical fiber communication system; a one-to-one correspondence relationship of the subcarrier signals; the receiving end generates indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal; the receiving end sends the indication information to The transmitting end.

Wherein, the one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end means that for each subcarrier signal in the first multicarrier signal, there is a unique An optimal phase compensation value is associated with the subcarrier signal, and the optimal phase compensation value is used for phase compensation of the subcarrier signal, that is, the number of the plurality of optimal compensation values is the same as the number of the plurality of subcarrier signals.

With the above solution, the indication information sent by the receiving end to the transmitting end includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end, and the transmitting end includes the indication information according to the indication information. The one-to-one correspondence uses a plurality of optimal phase compensation values to phase compensate a plurality of subcarrier signals in the first multicarrier signal. Since the transmitting end performs dispersion compensation on the first multi-carrier signal, a plurality of optimal phase compensation values are used according to a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multi-carrier signal. For the dispersion compensation of the plurality of subcarrier signals in the first multicarrier signal, the method provided by the second aspect is directed to the first multicarrier, compared with the prior art using the dispersion expression to compensate the signal to be transmitted at the transmitting end. Each subcarrier signal in the signal is separately compensated, and thus the dispersion compensation is more accurate.

In a possible design, before the receiving end determines the one-to-one correspondence, the following steps may be performed to determine the one-to-one correspondence: the receiving end receives the plurality of second optical signals sent by the transmitting end, and the plurality of second optical signals The plurality of second multi-carrier signals are respectively optically modulated by the transmitting end, and the plurality of second multi-carrier signals are each preset phase compensation of the plurality of preset phase compensation values for the transmitting end. The values are respectively obtained by phase-compensating each sub-carrier signal in the first multi-carrier signal; the receiving end calculates a performance index value of the plurality of sub-carrier signals included in each of the plurality of second optical signals; And determining, according to the calculated performance indicator value, an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal.

In a specific implementation, the receiving end respectively determines an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal according to the calculated performance index value, which can be implemented as follows:

For any one of the first multicarrier signals:

The receiving end acquires, from the calculated performance indicator value, a performance indicator value of the subcarrier signal of each of the plurality of second optical signals; the receiving end determines the performance index value of the subcarrier signal in each second optical signal. The optimal performance index value, and the preset phase compensation value used when obtaining the optimal performance index value is taken as the optimal phase compensation value corresponding to the subcarrier signal.

In a possible design, the performance index values of the plurality of subcarrier signals included in each second optical signal include a signal to noise ratio SNR and/or a bit error rate BER;

When the performance indicator value includes the SNR, the receiving end determines the optimal performance index value of the performance index value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value when the optimal performance index value is obtained. The optimal phase compensation value corresponding to the subcarrier signal is specifically: the receiving end determines the SNR maximum value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value used when obtaining the SNR maximum value as the sub The optimal phase compensation value corresponding to the carrier signal;

When the performance indicator value includes the BER, the receiving end determines the optimal performance index value of the performance index value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value when the optimal performance index value is obtained. The optimal phase compensation value corresponding to the subcarrier signal is specifically: the receiving end determines the SNR maximum value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value used when obtaining the SNR maximum value as the sub The optimum phase compensation value corresponding to the carrier signal.

In a third aspect, an embodiment of the present invention provides a dispersion compensation apparatus, where the apparatus includes:

a receiving module, configured to receive indication information sent by a receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted;

a phase compensation module, configured to perform phase compensation on the plurality of subcarrier signals by using a plurality of optimal phase compensation values according to a one-to-one correspondence included in the indication information received by the receiving module, to obtain a second multicarrier signal;

An optical modulation module, configured to perform optical modulation on the second multi-carrier signal obtained by the phase compensation module to obtain a first optical signal;

And a sending module, configured to send the first optical signal modulated by the optical modulation module to the receiving end.

Wherein, the one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end means that there is only one for each subcarrier signal in the first multicarrier signal. An optimal phase compensation value is associated with the subcarrier signal, and the optimal phase compensation value is used for phase compensation of the subcarrier signal, and the number of the plurality of optimal compensation values is the same as the number of the plurality of subcarrier signals.

With the above solution, the indication information sent by the receiving end to the receiving module includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end, and the phase compensation module follows the indication information. The one-to-one correspondence includes a phase compensation of a plurality of subcarrier signals in the first multicarrier signal by using a plurality of optimal phase compensation values. The phase compensation module uses a plurality of optimal phase compensation according to a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal when performing dispersion compensation on the first multicarrier signal. The value of the plurality of subcarrier signals in the first multicarrier signal is dispersion-compensated, and the device provided by the third aspect is the first one compared with the compensation of the signal to be transmitted at the transmitting end by using the dispersion expression in the prior art. Each subcarrier signal in the carrier signal is separately compensated, and thus the dispersion compensation is more accurate.

In a possible design, the device further includes: a determining module, configured to determine a plurality of preset phase compensation values before the receiving module receives the indication information sent by the receiving end; and the phase compensation module is further configured to adopt multiple Each preset phase compensation value of the preset phase compensation value phase compensates each subcarrier signal in the first multicarrier signal to obtain a third multicarrier signal; the optical modulation module is further configured to use the third multicarrier signal Performing optical modulation to obtain a second optical signal, where the second optical signal is used by the receiving end to determine the one-to-one correspondence according to performance index values of the plurality of subcarrier signals included in the second optical signal; and the sending module is further configured to use the second one. The optical signal is sent to the receiving end.

According to the above solution, the plurality of optimal phase compensation values are based on the phase compensation test of the first multi-carrier signal by using the plurality of preset phase compensation values respectively, and the receiving end is based on The performance index value of the plurality of subcarrier signals included in each of the second optical signals is determined. Since multiple optimal phase compensation values are factors influencing dispersion compensation in fiber-optic communication systems (eg, transmission distance, nonlinear factors and quantization noise of each device in the transmitting end, noise in the fiber link, etc.) are taken into consideration Thereafter, the receiving end determines the performance index value of the plurality of subcarrier signals included in each of the second optical signals, and thus may perform the phase compensated first multicarrier signal (ie, the second multicarrier The performance index value of the signal is better, and the performance index value of the first optical signal obtained by the second multi-carrier signal is also better.

In a possible design, the dispersion compensation apparatus provided by the above third aspect further includes: an inverse Fourier transform module, configured to: before the optical modulation module optically modulates the second multicarrier signal, to the second multicarrier The signal is inverse Fourier transformed. The second multicarrier signal in the frequency domain is thereby converted into a second multicarrier signal in the time domain. Converting the second multi-carrier signal in the frequency domain into the second multi-carrier signal in the time domain and then performing optical modulation is easier to implement.

In a fourth aspect, an embodiment of the present invention provides a dispersion compensation apparatus, the apparatus comprising:

a determining module, configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system;

The indication information generating module is configured to generate indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

The sending module is configured to send the indication information to the transmitting end.

The one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted refers to that, for each subcarrier signal in the first multicarrier signal, there is The only one of the best phase compensation values corresponds to the subcarrier signal, and the optimum phase compensation value is used for phase compensation of the subcarrier signal, and the number of the plurality of optimal compensation values is the same as the number of the plurality of subcarrier signals.

With the above solution, the indication information sent by the sending module end to the transmitting end includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end, and the transmitting end follows the indication information. The one-to-one correspondence includes a phase compensation of a plurality of subcarrier signals in the first multicarrier signal by using a plurality of optimal phase compensation values. Since the transmitting end performs dispersion compensation on the first multi-carrier signal, a plurality of optimal phase compensation values are used according to a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multi-carrier signal. For performing dispersion compensation on a plurality of subcarrier signals in the first multicarrier signal, the apparatus provided by the fourth aspect is directed to the first multicarrier, compared with the prior art using a dispersion expression to compensate a signal to be transmitted at a transmitting end. Multiple subcarrier signals in the signal are compensated separately, so dispersion compensation is more accurate.

In a possible design, the dispersion compensation apparatus further includes: a receiving module, configured to receive a plurality of second optical signals sent by the transmitting end, and the plurality of second optical signals are transmitted before the determining module determines the one-to-one correspondence The terminal respectively optically modulates the plurality of second multi-carrier signals, and the plurality of second multi-carrier signals are respectively used by the transmitting end to adopt a preset phase compensation value of each of the plurality of preset phase compensation values to the first multi-carrier signal respectively Each of the subcarrier signals is phase compensated;

When determining the one-to-one correspondence, the determining module is specifically configured to: calculate performance index values of the plurality of subcarrier signals included in each of the plurality of second optical signals; and determine the first according to the calculated performance index value The optimum phase compensation value corresponding to each subcarrier signal in a multicarrier signal.

In a specific implementation, the determining module respectively determines an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal according to the calculated performance indicator value, which can be implemented as follows:

Determining, from the calculated performance indicator value, a performance indicator value of a subcarrier signal of each of the plurality of second optical signals for each of the first multicarrier signals; determining each second light The optimal performance index value of the performance index value of the subcarrier signal in the signal, and the preset phase compensation value used when obtaining the optimal performance index value is used as the optimal phase compensation value corresponding to the subcarrier signal.

According to the above solution, the plurality of optimal phase compensation values are based on the phase compensation test of the first multi-carrier signal by using a plurality of preset phase compensation values respectively at the transmitting end, and the determining module is configured according to each of the second optical signals. The performance value of the plurality of subcarrier signals included in the second optical signal is determined. Since multiple optimal phase compensation values are factors influencing dispersion compensation in fiber-optic communication systems (eg, transmission distance, nonlinear factors and quantization noise of each device in the transmitting end, noise in the fiber link, etc.) are taken into consideration Thereafter, the determining module determines the performance index value of the plurality of subcarrier signals included in each of the second optical signals, and thus may perform the phase compensated first multicarrier signal (ie, the second multicarrier The performance index value of the signal is better, and the performance index value of the first optical signal obtained by the second multi-carrier signal is also better.

When the performance indicator value includes the SNR, the receiving end determines the optimal performance index value of the performance index value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value when the optimal performance index value is obtained. The optimal phase compensation value corresponding to the subcarrier signal is specifically: the receiving end determines the SNR maximum value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value used as the SNR maximum value as the subcarrier signal. Corresponding optimal phase compensation value;

According to the above scheme, each preset phase compensation value is set in the set interval, and the preset setting of the preset phase compensation value can be avoided; at the same time, the plurality of preset phase compensation values are evenly distributed evenly within the set interval. Distribution, so that multiple optimal phase compensation values are chosen to be more accurate, The effect of dispersion compensation is better.

In a fifth aspect, an embodiment of the present invention provides a dispersion compensation apparatus, where the apparatus includes:

a transceiver, configured to receive indication information sent by a receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted;

a digital signal processor, configured to perform phase compensation on the plurality of subcarrier signals by using a plurality of optimal phase compensation values according to a one-to-one correspondence included in the indication information received by the transceiver, to obtain a second multicarrier signal;

An electro-optic modulator for optically modulating a second multi-carrier signal obtained by the digital signal processor to obtain a first optical signal;

The transceiver is further configured to send the first optical signal modulated by the electro-optic modulator to the receiving end.

The dispersion compensation device provided by the fifth aspect can be used to perform the method provided by the first aspect, and can be regarded as a specific implementation manner of the dispersion compensation device provided by the third aspect.

In a sixth aspect, an embodiment of the present invention provides a dispersion compensation apparatus, where the apparatus includes:

a digital signal processor, configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system; and generate indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

The transceiver is configured to send the indication information to the transmitting end.

The dispersion compensation device provided by the sixth aspect can be used to perform the method provided by the second aspect, and can be regarded as a specific implementation manner of the dispersion compensation device provided by the fourth aspect.

DRAWINGS

1a is a schematic structural diagram of an optical fiber communication system according to an embodiment of the present invention;

1b is a schematic diagram of a function of a dispersion expression and a dispersion compensation value according to an embodiment of the present invention;

2 is a schematic flowchart of a dispersion compensation method according to an embodiment of the present invention;

3 is a schematic structural diagram of an IQ modulator according to an embodiment of the present invention;

4 is a schematic structural diagram of a dual-drive modulator according to an embodiment of the present invention;

5 is a schematic diagram of a signal-to-noise ratio of a first optical signal received by a receiving end after the dispersion compensation method shown in FIG. 2 and the dispersion compensation method provided by the prior art are provided according to an embodiment of the present invention;

6 is a schematic diagram of a bit error rate of a first optical signal received by a receiving end after the dispersion compensation method shown in FIG. 2 and the dispersion compensation method provided by the prior art are provided according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of signal to noise ratios of multiple subcarrier signals included in a plurality of second optical signals according to an embodiment of the present invention; FIG.

FIG. 8 is a schematic flowchart of performing phase compensation on a first multi-carrier signal by using a preset phase compensation value by using a cyclic process according to an embodiment of the present invention; FIG.

FIG. 9 is a schematic diagram of a detailed processing flow of a transmitting end and a receiving end when the dispersion compensation method in the embodiment of the present invention is used according to an embodiment of the present disclosure;

FIG. 10 is a schematic structural diagram of a first dispersion compensation apparatus according to an embodiment of the present disclosure;

FIG. 11 is a schematic structural diagram of a second dispersion compensation apparatus according to an embodiment of the present invention;

FIG. 12 is a schematic structural diagram of a third dispersion compensation apparatus according to an embodiment of the present invention; FIG.

FIG. 13 is a schematic structural diagram of a fourth dispersion compensation apparatus according to an embodiment of the present invention.

detailed description

For a better understanding of the above objects, aspects and advantages of the present invention, a detailed description is provided below. The detailed description sets forth various embodiments of the devices and/or methods in the <RTIgt; In these block diagrams, flowcharts, and/or examples, one or more functions and/or operations are included. Those skilled in the art will appreciate that the various functions and/or operations within the block diagrams, flowcharts or examples can be implemented individually or collectively by various hardware, software, firmware, or by any of hardware, software and firmware. Combined implementation.

Embodiments of the invention are applied to fiber optic communication systems. A schematic diagram of the structure of the fiber optic communication system can be as shown in Figure 1a. In Figure 1a, a fiber optic communication system consists of a transmitting end and a receiving end. The transmitting end obtains the optical signal by encoding, modulating and the like of the electrical signal, and the optical signal is transmitted to the optical fiber through the optical amplifier for transmission; the optical signal received by the receiving end from the optical fiber passes through the optical amplifier and is received by the receiving end. After demodulation, decoding, etc., the electrical signal is restored. The electrical signal recovered by the receiving end is the electrical signal before the transmitting end encodes and modulates the processing. Thereby, the electrical signal is transmitted from the transmitting end to the receiving end through the optical fiber communication system.

In the field of optical fiber communication, the dispersion problem of optical signals in optical fiber links has always been a major problem that restricts the performance of optical fiber communication systems. In order to solve the dispersion problem in the fiber link, a dispersion compensation scheme is generally adopted. For example, by predicting the dispersion expression H(w), the inverse function 1/H(w) of the dispersion expression is superimposed on the signal to be transmitted at the transmitting end, and then the inverse of the Fourier transform, light modulation, etc. are performed on the transmitted signal. After that, it is transmitted to the receiving end. As shown in FIG. 1b, assuming that the dispersion expression H(w) is as shown by the dashed line in FIG. 1b, when the dispersion compensation is performed, the dispersion expression H(w) is inverted to obtain the inverse function of the dispersion expression, ie The dispersion compensation value is 1/H(w), as shown by the solid line in Figure 1b. The dispersion compensation value 1/H(w) shown by the solid line in Fig. 1b is superimposed on the signal to be transmitted to achieve dispersion compensation.

The above dispersion compensation method has a problem that the dispersion compensation value is inaccurate. This is because the dispersion expression is an estimated expression, and the actual parameters in the dispersion expression are difficult to obtain accurately by the prediction method, thus causing inaccuracy of the dispersion expression, which in turn leads to inaccurate dispersion compensation values. Moreover, there are many factors affecting the dispersion in the fiber link, such as the nonlinearity of the modulator and the driver, the quantization noise of each device, etc., and only the dispersion compensation is performed according to the dispersion form type of all subcarrier signals in the signal to be transmitted. Even if the dispersion expression is accurate, the dispersion compensation value is not accurate.

Embodiments of the present invention provide a dispersion compensation method for compensating for dispersion in a fiber-optic communication system. As shown in Figure 2, the method includes:

S201: The receiving end of the optical fiber communication system determines a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system.

The embodiment of the present invention is applied to an optical fiber communication system. In the embodiment of the present invention, the transmitting end refers to the transmitting end of the optical fiber communication system, and the receiving end refers to the receiving end of the optical fiber communication system.

In S201, the one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end is that, for each subcarrier signal in the first multicarrier signal, there is The only one of the best phase compensation values corresponding to the The subcarrier signal is phase compensated, that is, the number of the plurality of optimal compensation values is the same as the number of the plurality of subcarrier signals. For example, the first multicarrier signal includes three subcarrier signals λ1, λ2, and λ3, and then the number of the plurality of optimal phase compensation values is also three, that is, θ1, θ2, and θ3. For example, the one-to-one correspondence between the optimal compensation value and the subcarrier signal may be that θ1 is the optimal phase compensation value for phase compensation of λ1, θ2 is the optimum phase compensation value for phase compensation of λ2, and θ3 is for λ3 The best phase compensation value for phase compensation.

S202: The receiving end generates indication information.

The indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal.

S203: The receiving end sends the generated indication information to the transmitting end.

S204: The transmitting end receives the indication information sent by the receiving end, and performs phase compensation on the plurality of subcarrier signals in the first multicarrier signal by using multiple optimal phase compensation values according to the one-to-one correspondence relationship to obtain a second multicarrier signal. .

According to the one-to-one correspondence, the phase compensation of the plurality of subcarrier signals in the first multicarrier signal by using the plurality of optimal phase compensation values is: determining, for each subcarrier signal in the first multicarrier signal, The optimal phase compensation value corresponding to the subcarrier signal indicated in the one-to-one correspondence, and phase compensation of the subcarrier signal by using the determined optimal phase compensation value. Assuming that the first multicarrier signal includes three subcarrier signals λ1, λ2, and λ3, the three optimal phase compensation values determined by the receiving end are θ1, θ2, and θ3, and the plurality of optimal compensation values are one by one of the plurality of subcarrier signals. The correspondence relationship is: θ1 is the optimum phase compensation value for phase compensation of λ1, θ2 is the optimum phase compensation value for phase compensation of λ2, and θ3 is the optimum phase compensation value for phase compensation of λ3. Therefore, when S204 is executed, phase compensation is performed on λ1 by θ1, phase compensation is performed on λ2 by θ2, and phase compensation is performed on λ3 by θ3.

It should be noted that the step of performing phase compensation on multiple subcarrier signals in the first multicarrier signal by using multiple optimal phase compensation values in S204 needs to be performed in the frequency domain, so if the first multicarrier signal is a time domain signal Then, the first multi-carrier signal needs to be Fourier transformed before S204, and the obtained first multi-carrier signal is a frequency domain signal, and then the plurality of sub-carriers of the transformed first multi-carrier signal The carrier signal is phase compensated.

S205: The transmitting end optically modulates the second multi-carrier signal to obtain a first optical signal.

Optionally, before the transmitting end optically modulates the second multi-carrier signal in S205, the second multi-carrier signal may also be subjected to inverse Fourier transform.

Performing an inverse Fourier transform on the second multicarrier signal actually converts the second multicarrier signal in the frequency domain into a second multicarrier signal in the time domain. Converting the second multi-carrier signal in the frequency domain into the second multi-carrier signal in the time domain and then performing optical modulation is easier to implement.

S206: The transmitting end sends the first optical signal to the receiving end.

The optical modulation refers to modulating a continuous wave (CW) by a second multi-carrier signal, and outputting a first optical signal, and the output first optical signal carries source information included in the second multi-carrier signal. . The first optical signal can be transmitted to the receiving end through the optical fiber, so that the source information carried in the first optical signal can be transmitted to the receiving end. Optical modulation is usually implemented by an optical modulator. There are two inputs to the optical modulator, one is CW, and the other is a second multi-carrier signal containing source information. Usually, the second multi-carrier signal is divided into two inputs. Light modulator.

In the embodiment of the present invention, the optical modulator may be an In-phase Quadrature (IQ) modulator or a dual-drive modulator. Regardless of whether the optical modulator is an IQ modulator or a dual-drive modulator, the transmitting end can adopt either a single sideband modulation method or a double sideband modulation method when optically modulating the signal.

The structure of the IQ modulator can be as shown in Figure 3. When the IQ modulator shown in FIG. 3 is used to optically modulate the second multicarrier signal, the I port is used to input the CW, the O port is used to output the first optical signal, and the A1 port and the A2 port are used to use the second multicarrier. The signal is divided into two inputs and two modulators. These two modulators are generally Mach-Zehnder-Modulator (MZM), and the two modulators respectively modulate the two second multi-carrier signals. In the IQ modulator, the B1, B2, and B3 ports are used to adjust the bias point of the IQ modulator, typically B1, B2, and B3 are set at π/2, π/2, and π/2, respectively. If the IQ modulator modulates the second multicarrier signal by using a single sideband modulation mode, the output first optical signal is a single sideband signal; if the IQ modulator modulates the second multicarrier signal, double sideband modulation is used. In the mode, the output first optical signal is a double sideband signal. Among them, single sideband letter Only one sideband of the number carries the source information in the second multi-carrier signal, and both sidebands of the double-sideband signal carry the source information in the second multi-carrier signal.

The structure of the dual drive modulator can be as shown in FIG. When the dual-drive modulator shown in FIG. 4 is used for optical modulation of the second multi-carrier signal, the I port is used for inputting CW, the O port is for outputting the first optical signal, and the A1 port and the A2 port are used for the second most The carrier signal is divided into two channels and two modulators are respectively input. The two modulators are generally Phase Modulators (PM), and the two modulators respectively modulate the two second multi-carrier signals. In the dual drive modulator, B1 and B2 are used to adjust the bias point of the dual drive modulator. In the dual-drive modulator, it is generally ensured that the difference between B1 and B2 is π/2, and the specific values of B1 and B2 are not limited. If the dual-drive modulator modulates the second multi-carrier signal by using a single sideband modulation method, the output first optical signal is a single sideband signal; if the dual-drive modulator modulates the second multi-carrier signal, bilaterally With modulation mode, the output first optical signal is a double sideband signal.

In the chromatic dispersion compensation method shown in FIG. 2, the indication information sent by the receiving end to the transmitting end includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end, The transmitting end performs phase compensation on the plurality of subcarrier signals in the first multicarrier signal by using a plurality of optimal phase compensation values according to the one-to-one correspondence included in the indication information. In the dispersion compensation method shown in FIG. 2, since the transmitting end performs dispersion compensation on the first multi-carrier signal, the one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of sub-carrier signals in the first multi-carrier signal is performed. Relationship, using a plurality of optimal phase compensation values to perform dispersion compensation on a plurality of subcarrier signals in the first multicarrier signal, compared with the prior art using a dispersion expression to compensate a signal to be transmitted at a transmitting end, FIG. 2 In the method, the plurality of subcarrier signals in the first multicarrier signal are respectively compensated, and thus the dispersion compensation is more accurate.

FIG. 5 is a graph showing a signal-to-noise ratio (SNR) of a first optical signal received by a receiving end after the dispersion compensation method shown in FIG. 2 and the dispersion compensation method provided by the prior art are used. It can be seen from FIG. 5 that the SNR compensation method shown in FIG. 2 can improve the SNR of the first optical signal received by the receiving end, and the effect of compensating for the dispersion is better. 6 is a first optical signal received by the receiving end after the dispersion compensation method shown in FIG. 2 and the dispersion compensation method provided by the prior art are used. The curve of the Bit Error Rate (BER). It can be seen from FIG. 6 that the BER compensation method shown in FIG. 2 can reduce the BER of the first optical signal received by the receiving end, and the effect of compensating for the dispersion is better.

In addition, before performing S201, the receiving end determines a plurality of optimal phase compensation values, which can be implemented by the transmitting end and the receiving end by performing the following steps:

At the transmitting end, determining a plurality of preset phase compensation values; respectively performing, by using each of the plurality of preset phase compensation values, the following operation on the first multi-carrier signal: the transmitting end adopts the preset phase compensation value Phase compensation is performed on each subcarrier signal in the first multicarrier signal to obtain a third multicarrier signal, and the transmitting end optically modulates the third multicarrier signal to obtain a second optical signal, and sends the second optical signal to the receiving end. Since the first multi-carrier signal is phase-compensated by using each of the preset phase compensation values, and then the second optical signal is obtained, the number of the second optical signals sent by the transmitting end to the receiving end is Same as the preset phase compensation value.

At the receiving end, the receiving end receives a plurality of second optical signals sent by the transmitting end, and calculates performance index values of the plurality of subcarrier signals included in each of the plurality of second optical signals, assuming the second optical signal The number is M, and the number of subcarrier signals included in each second optical signal is N. For the same performance indicator, the number of performance index values to be calculated is the product of M and N, and M and N are positive integers. The receiving end respectively determines an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal according to the calculated performance indicator value.

The receiving end calculates performance index values of the plurality of subcarrier signals included in each of the plurality of second optical signals, and determines each subcarrier in the first multicarrier signal according to the calculated performance index value. The optimal phase compensation value corresponding to the signal can be understood as: for any one of the first multi-carrier signals, the receiving end acquires each of the plurality of second optical signals from the calculated performance indicator value. The performance index value of the subcarrier signal, that is, the same performance index, the number of performance index values of the subcarrier signal obtained is the same as the number of the second optical signal; determining the subcarrier signal in each second optical signal The optimal performance index value of the performance index value, and the preset phase compensation value used when obtaining the optimal performance index value is used as the optimal phase compensation value corresponding to the subcarrier signal.

Exemplarily, assuming that the number of preset phase compensation values is three in the above implementation manner, then After the processing at the transmitting end, three second optical signals respectively corresponding to the three preset phase compensation values can be obtained. At this time, for any one of the first multi-carrier signals, the sub-carrier signal has three performance index values, that is, each second optical signal corresponds to a performance index value of the sub-carrier signal. The receiving end obtains the optimal performance index value among the three performance index values, and the preset phase compensation value used by the corresponding second optical signal when obtaining the optimal performance index value is the optimal phase compensation of the subcarrier signal. value.

In the embodiment of the present invention, when the transmitting end performs the above three operations of phase compensation, optical modulation, and transmitting the second optical signal on the first multi-carrier signal by using each preset phase compensation value, a preset phase compensation may be adopted. After performing the above three operations on the first multi-carrier signal, performing the above three operations on the first multi-carrier signal by using another preset phase compensation value; or using a preset phase compensation value for the first multiple When the carrier signal does not perform the above three operations, the third operation is performed on the first multicarrier signal by using another preset phase compensation value. For example, when a plurality of preset phase compensation values are π/4 and π/2, a second optical signal can be obtained after phase compensation and optical modulation of the first multicarrier signal by using π/4, and then π/ is used. 2 performing phase compensation and optical modulation on the first multi-carrier signal to obtain another second optical signal, and then transmitting two second optical signals respectively.

The receiving end needs to determine the performance index value of the plurality of subcarrier signals included in each of the plurality of second optical signals when determining the optimal phase compensation value of each subcarrier signal. The performance indicator values of the plurality of subcarrier signals included in each second optical signal include SNR and/or BER.

When the performance indicator value includes the BER, the receiving end determines the optimal performance index value of the performance index value of the subcarrier signal in each second optical signal, and uses the preset phase compensation value when the optimal performance index value is obtained. The optimal phase compensation value corresponding to the subcarrier signal is specifically: the receiving end determines each The SNR maximum value of the subcarrier signal in the second optical signal, and the preset phase compensation value used when obtaining the SNR maximum value is taken as the optimal phase compensation value corresponding to the subcarrier signal.

It should be noted that the performance index value of the second optical signal is not limited to the SNR and the BER, and other performance indicators that can be used to measure the performance of the second optical signal may also be used as the multiple optimal phase compensation values in the embodiment of the present invention. Basis.

Exemplarily, when the performance index of the second optical signal is SNR, and the plurality of preset phase compensation values are π/5, 2π/5, 3π/5, 4π/5, and π, respectively, in a fiber-optic communication system The SNRs of the plurality of subcarrier signals included in the five second optical signals calculated by the receiving end may be as shown in FIG. 7. In FIG. 7, the SNRs of the plurality of subcarrier signals included in the second optical signal when different preset phase compensation values are used are distinguished by different line types, and the optimal compensation value curve represents the plurality of sub-inclusions included by the receiving end according to the five second optical signals. A plurality of optimal phase compensation values determined by the performance index value of the carrier signal.

In the following, the specific example shows how the receiving end determines the optimal phase compensation value of one of the first multi-carrier signals. Taking the performance index value SNR of the five second optical signals shown in FIG. 7 as an example, it is assumed that the receiving end determines the optimum phase compensation value of the subcarrier signal having a frequency of 20 GHz. 7 , for a subcarrier signal having a frequency of 20 GHz, the receiving end can obtain the SNR of the subcarrier signal on each of the five second optical signals; since the subcarrier signal for the second optical signal is When the value of SNR is large, the performance index value is superior, so the receiving end determines the largest SNR among the five SNRs, that is, the SNR of the subcarrier signal in the second optical signal represented by the square line type; Multi-carrier signal phase compensation The preset phase compensation value used to obtain the maximum SNR is used as the optimum phase compensation value of the sub-carrier signal, that is, the preset phase compensation used for the SNR of the sub-carrier signal represented by the block line type. The value is 2π/5.

It should be noted that the more the preset phase compensation value is, the more accurate the dispersion compensation method provided by the embodiment of the present invention is. In the embodiment of the present invention, each of the preset phase compensation values may be set in the same setting interval. For example, the setting interval may be [0, π] or [0, 2π ]. Limiting the range of values of the plurality of preset phase compensation values can avoid repeated setting of the preset phase compensation values. For example, the two preset phase compensation values are π/3 and 7π/3, respectively, and the two preset phase compensation values are respectively The effect of phase compensation on a subcarrier signal is the same, so the two preset phases The bit offset value is the preset phase offset value that is set repeatedly.

In addition, after setting each of the preset phase compensation values to be within the same setting interval, further setting when the plurality of preset phase compensation values are arranged in numerical order The difference between any two adjacent preset phase compensation values of the preset phase compensation values is a preset step size. The advantage of this arrangement is that a plurality of preset phase compensation values can be evenly distributed within the above-mentioned set interval, so that a plurality of optimal phase compensation values are selected more accurately, so that the effect of dispersion compensation is better. Among them, the smaller the value of the preset step size, the better the dispersion compensation effect.

According to the above method for determining a plurality of optimal phase compensation values, the plurality of optimal phase compensation values are based on the phase compensation test of the first multi-carrier signal by using a plurality of preset phase compensation values at the transmitting end, respectively, by the receiving end Determining according to performance index values of the plurality of subcarrier signals included in each of the second optical signals. Since multiple optimal phase compensation values are factors influencing dispersion compensation in fiber-optic communication systems (eg, transmission distance, nonlinear factors and quantization noise of each device in the transmitting end, noise in the fiber link, etc.) are taken into consideration Thereafter, the receiving end determines the performance index value of the plurality of subcarrier signals included in each of the second optical signals, and thus may perform the phase compensated first multicarrier signal (ie, the second multicarrier The performance index value of the signal is better, and the performance index value of the first optical signal obtained by the second multi-carrier signal is also better.

In order to facilitate phase compensation of the first multi-carrier signal by using each of the preset phase compensation values, and performing optical modulation on the obtained third multi-carrier signal to obtain the second optical signal. The process can be implemented by a cyclic process. Assuming that the setting interval is [0, π] and the preset step size is π/N, the process of the loop operation can be as shown in FIG. In FIG. 8, when a plurality of preset phase compensation values are arranged in numerical order, the first preset phase compensation value set by the transmitting end is 0, and the second preset phase compensation value is π/N, The three preset phase compensation values are 2π/N... and so on. In FIG. 8, after phase compensation is performed on the first multi-carrier signal by using each preset phase compensation value, the obtained third multi-carrier signal needs to be optically modulated, and the obtained second optical signal is sent to the receiving end. Then, the next preset phase compensation value is calculated by superimposing π/N, and then the above phase compensation→light modulation→transmission of the second optical signal is repeated for the calculated next preset phase compensation value. In FIG. 8, the dispersion compensation provided by the embodiment of the present invention can be adjusted by setting the value of N. The dispersion compensation accuracy of the compensation method, the larger the value of N, the smaller the preset step size, and the greater the number of preset phase compensation values, the higher the accuracy of dispersion compensation.

In summary, the dispersion compensation method shown in FIG. 2 can more accurately compensate the dispersion in the optical fiber communication system than the dispersion compensation method in the prior art.

In combination with the above, FIG. 9 provides a detailed processing flow of the transmitting end and the receiving end when the dispersion compensation method in the embodiment of the present invention is adopted. The process flow shown in FIG. 9 can be regarded as a specific implementation of the dispersion compensation method shown in FIG. 2. As shown in FIG. 9, after transmitting (Mapping) and serial-to-parallel conversion (S/P) to a binary sequence (Transmitter), the multi-channel parallel time domain signal obtained by serial-to-parallel conversion is subjected to IFFT. Obtaining a multi-channel parallel frequency domain signal, that is, the first multi-carrier signal in the embodiment of the present invention; then adding the first multi-carrier signal to a Cyclic Prefix (CP) and outputting to the sub-carrier signal phase compensation module (Phase) Comp.For subcarriers); the subcarrier signal phase compensation module uses the dispersion compensation method shown in FIG. 2 to perform dispersion compensation on a plurality of subcarrier signals in the first multicarrier signal, and then outputs a second multicarrier signal; The signal is subjected to parallel-to-serial conversion (P/S) to obtain a serial frequency domain signal, and the serial frequency domain signal is divided into two outputs, and each serial frequency domain signal is subjected to a digital-to-analog converter (DAC). The digital-to-analog conversion, the amplifier performs amplification, and the attenuator performs attenuation processing, and then inputs to the dual-drive modulator. After the double-drive modulator double-bands the second multi-carrier signal, the obtained first optical signal is output to the reception. At the receiving end, after the receiving end performs the operation opposite to the operation of the transmitting end on the first optical signal, the binary sequence transmitted by the transmitting end can be restored. Since the subcarrier signal phase compensation module in FIG. 9 adopts the dispersion compensation method shown in FIG. 2, dispersion compensation can be performed more accurately on the optical fiber communication system than in the prior art.

In addition, the receiving end may set a subcarrier signal SNR calculation module (SNR Cal. For subcarriers), and the module may calculate multiple subcarriers included in each second optical signal after receiving the plurality of second optical signals sent by the transmitting end. The SNR of the signal; the receiving end may further set a BER calculation module (BER Calculation), the module may calculate the BER of the plurality of subcarrier signals included in each second optical signal after receiving the plurality of second optical signals sent by the transmitting end . Further, the receiving end may determine the first multiple according to the calculated value of the SNR and/or the value of the BER of the plurality of subcarrier signals included in each second optical signal. The optimal phase compensation value corresponding to each subcarrier signal in the carrier signal, and the calculated plurality of optimal phase compensation values may be respectively used for the subcarrier signal phase compensation module of the transmitting end and the plurality of subcarrier signals of the first multicarrier signal Perform phase compensation.

Embodiments of the present invention provide a dispersion compensation apparatus that can be used to perform operations performed by a transmitting end in the method shown in FIG. 2. As shown in FIG. 10, the dispersion compensation device 1000 includes:

The receiving module 1001 is configured to receive indication information sent by the receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted;

The phase compensation module 1002 is configured to perform phase compensation on the plurality of subcarrier signals by using a plurality of optimal phase compensation values according to the one-to-one correspondence included in the indication information received by the receiving module 1001, to obtain a second multicarrier signal;

The optical modulation module 1003 is configured to perform optical modulation on the second multi-carrier signal compensated by the phase compensation module 1002 to obtain a first optical signal.

The sending module 1004 is configured to send the first optical signal modulated by the optical modulation module 1003 to the receiving end.

Optionally, the dispersion compensation apparatus 1000 further includes: a determining module, configured to determine a plurality of preset phase compensation values before the receiving module 1001 receives the indication information sent by the receiving end; the phase compensation module 1002 is further configured to adopt multiple Each preset phase compensation value of the preset phase compensation value phase compensates each subcarrier signal in the first multicarrier signal to obtain a third multicarrier signal; the optical modulation module 1003 is further configured to use the third multicarrier The signal is optically modulated to obtain a second optical signal, and the second optical signal is used by the receiving end to determine a one-to-one correspondence according to performance index values of the plurality of subcarrier signals included in the second optical signal; the transmitting module 1004 is further configured to use the second The optical signal is sent to the receiving end.

Optionally, the performance indicator value of the multiple subcarrier signals included in the second optical signal includes a signal to noise ratio SNR and/or a bit error rate BER; and for any one of the first multicarrier signals, the performance indicator value includes an SNR. The preset phase compensation value used when the SNR of the plurality of second optical signals is maximum is the optimal phase compensation value corresponding to the subcarrier signal; when the performance index value includes the BER, the plurality of second optical signal neutrons The preset phase compensation value used when the BER of the carrier signal is minimum is The optimum phase compensation value corresponding to the carrier signal.

Optionally, each of the preset phase compensation values is located in the same setting interval; when the plurality of preset phase compensation values are arranged in an increasing order of values, the plurality of preset phase compensation values The difference between any two adjacent preset phase compensation values is a preset step size.

Optionally, the dispersion compensation apparatus 1000 further includes: an inverse Fourier transform module, configured to perform inverse Fourier transform on the second multicarrier signal before the optical modulation module 1003 optically modulates the second multicarrier signal.

It should be noted that the dispersion compensation apparatus 1000 provided by the embodiment of the present invention can be used to perform the operations performed by the transmitting end in the dispersion compensation method shown in FIG. 2, and the implementation manner not explained and described in detail by the dispersion compensation apparatus 1000 can be referred to FIG. A related description in the dispersion compensation method shown.

It should be noted that the division of the module in the embodiment of the present invention is schematic, and is only a logical function division, and the actual implementation may have another division manner. In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules.

Based on the above embodiments, an embodiment of the present invention further provides a dispersion compensation apparatus. As shown in FIG. 11, the dispersion compensating apparatus 1100 can perform the method provided by the embodiment corresponding to FIG. 2, which can be the same as the dispersion compensating apparatus 1000 shown in FIG.

The dispersion compensation device 1100 includes:

The transceiver 1101 is configured to receive indication information sent by the receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted;

The digital signal processor 1102 is configured to perform phase compensation on the plurality of subcarrier signals by using a plurality of optimal phase compensation values according to a one-to-one correspondence included in the indication information received by the transceiver 1101, to obtain a second multicarrier signal;

An electro-optic modulator 1103, configured to perform optical modulation on the second multi-carrier signal obtained by the digital signal processor to obtain a first optical signal;

The transceiver 1101 is further configured to send the first optical signal modulated by the electro-optic modulator to the receiving end.

It should be noted that the dispersion compensation device 1100 may be the same device as the dispersion compensation device 1000 shown in FIG. The transceiver 1101 can be used to perform operations performed by the receiving module 1001 and the transmitting module 1004 in the dispersion compensation device 1000, and the digital signal processor 1102 can be used to perform operations performed by the phase compensation module 1002 in the dispersion compensation device 1000, the electro-optic modulator 1103 It can be used to perform the operations performed by the light modulation module 1003 in the dispersion compensation device 1000. Further, the digital signal processor 1102 can be used to perform operations performed by the determination module and the inverse Fourier transform module in the dispersion compensation device 1000. Implementations not specifically explained and described in the dispersion compensation device 1100 can be referred to the relevant description in the dispersion compensation device 1100.

The embodiment of the invention provides a dispersion compensation device, which can be used to perform the operations performed by the receiving end in the method shown in FIG. 2. As shown in FIG. 12, the dispersion compensation device 1200 includes:

The determining module 1201 is configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system;

The indication information generating module 1202 is configured to generate indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

The sending module 1203 is configured to send the indication information to the transmitting end.

Optionally, the dispersion compensation device 1200 further includes: a receiving module, configured to receive, by the determining module 1201, a plurality of second optical signals sent by the transmitting end, where the plurality of second optical signals are respectively sent by the transmitting end, before the determining module 1201 determines the one-to-one correspondence And obtaining, by the plurality of second multi-carrier signals, the plurality of second multi-carrier signals, wherein each of the plurality of preset phase compensation values is used by the transmitting end, respectively, for each of the first multi-carrier signals When the sub-carrier signals are phase-compensated, the determining module 1201 is configured to: calculate a performance index value of the plurality of sub-carrier signals included in each of the plurality of second optical signals; And determining, according to the calculated performance indicator value, an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal.

Optionally, the determining module 1201 is configured to: determine, according to the calculated performance indicator value, an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal, specifically: for any of the first multicarrier signals a subcarrier signal, obtaining a plurality of second lights from the calculated performance indicator values a performance index value of a subcarrier signal of each second optical signal in the signal; determining an optimal performance index value of a performance index value of the subcarrier signal in each second optical signal, and obtaining an optimal performance index value The preset phase compensation value is adopted as the optimal phase compensation value corresponding to the subcarrier signal.

Optionally, the performance indicator value of the multiple subcarrier signals included in each second optical signal includes a signal to noise ratio SNR and/or a bit error rate BER;

When the performance indicator value includes the SNR, the determining module 1201 determines the optimal performance index value among the performance index values of the subcarrier signals in each second optical signal, and uses the preset phase compensation when obtaining the optimal performance index value. The value is used as the optimal phase compensation value corresponding to the subcarrier signal, and is specifically used to: determine the SNR maximum value of the subcarrier signal in each second optical signal, and use the preset phase compensation value used as the SNR maximum value as a sub- The optimal phase compensation value corresponding to the carrier signal;

When the performance indicator value includes the BER, the determining module 1201 determines the optimal performance index value of the performance index value of the subcarrier signal in each second optical signal, and uses the preset phase compensation when obtaining the optimal performance index value. The value is used as the optimal phase compensation value corresponding to the subcarrier signal, and is specifically used to: determine the SNR maximum value of the subcarrier signal in each second optical signal, and use the preset phase compensation value used as the SNR maximum value as a sub- The optimum phase compensation value corresponding to the carrier signal.

It should be noted that the dispersion compensation apparatus 1200 provided by the embodiment of the present invention can be used to perform the operations performed by the receiving end in the dispersion compensation method shown in FIG. 2, and the implementation manner not explained and described in detail by the dispersion compensation apparatus 1200 can be referred to FIG. A related description in the dispersion compensation method.

Based on the above embodiments, an embodiment of the present invention further provides a dispersion compensation apparatus. As shown in FIG. 13, the dispersion compensation device 1300 can perform the method provided by the embodiment corresponding to FIG. 2, which can be the same as the dispersion compensation device 1200 shown in FIG.

The dispersion compensation device 1300 includes:

The digital signal processor 1301 is configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system; Generating indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

The transceiver 1302 is configured to send the indication information to the transmitting end.

It should be noted that the dispersion compensation device 1300 may be the same device as the dispersion compensation device 1200 illustrated in FIG. The transceiver 1302 can be used to perform operations performed by the transmitting module 1203 and the receiving module in the dispersion compensating device 1200, and the digital signal processor 1301 can be used to perform operations performed by the determining module 1201 and the indication information generating module 1202 in the dispersion compensating device 1200. Implementations not specifically explained and described in the dispersion compensation device 1300 can be referred to the relevant description in the dispersion compensation device 1200.

In summary, embodiments of the present invention provide a dispersion compensation method and apparatus to more accurately compensate dispersion in a fiber-optic communication system.

Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) including computer usable program code.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (system), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The device is implemented in a flow chart or Multiple processes and/or block diagrams The functions specified in one or more boxes.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Although the preferred embodiment of the invention has been described, it will be apparent to those skilled in the < Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and the modifications and

It is apparent that those skilled in the art can make various modifications and variations to the embodiments of the invention without departing from the spirit and scope of the embodiments of the invention. Thus, it is intended that the present invention cover the modifications and modifications of the embodiments of the invention.

Claims

A dispersion compensation method, comprising:

The transmitting end receives the indication information sent by the receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end. ;

The transmitting end performs phase compensation on the plurality of subcarrier signals by using the plurality of optimal phase compensation values according to the one-to-one correspondence, to obtain a second multi-carrier signal;

The transmitting end optically modulates the second multi-carrier signal to obtain a first optical signal, and sends the first optical signal to the receiving end.
The method according to claim 1, wherein before the transmitting end receives the indication information sent by the receiving end, the method further includes:

The transmitting end determines a plurality of preset phase compensation values;

The transmitting end performs the following operations on the first multi-carrier signal by using each of the preset preset phase compensation values:

Performing phase compensation on each subcarrier signal in the first multicarrier signal by using the preset phase compensation value to obtain a third multicarrier signal;

Performing optical modulation on the third multi-carrier signal to obtain a second optical signal, and transmitting the second optical signal to the receiving end, where the second optical signal is used by the receiving end according to the second The performance index values of the plurality of subcarrier signals included in the optical signal determine the one-to-one correspondence.
The method according to claim 2, wherein the performance index value of the plurality of subcarrier signals included in the second optical signal comprises a signal to noise ratio SNR and/or a bit error rate BER;

And determining, by using the SNR, the preset phase compensation value used when the SNR of the subcarrier signal is the largest among the plurality of second optical signals, for any one of the first multicarrier signals Determining an optimal phase compensation value corresponding to the subcarrier signal; when the performance indicator value includes the BER, the preset phase compensation value used when the BER of the subcarrier signal is the smallest among the plurality of second optical signals is the sub The optimum phase compensation value corresponding to the carrier signal.
The method according to claim 2 or 3, wherein each of the plurality of preset phase compensation values is located in the same setting interval; and when the plurality of preset phase compensation values are When the values are sequentially increased, the difference between any two adjacent preset phase compensation values of the plurality of preset phase compensation values is a preset step size.
The method according to any one of claims 1 to 4, wherein before the transmitting end optically modulates the second multi-carrier signal, the method further includes:

The transmitting end performs inverse Fourier transform on the second multicarrier signal.
A dispersion compensation method, comprising:

The receiving end determines a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system;

The receiving end generates indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and a plurality of subcarrier signals in the first multicarrier signal;

The receiving end sends the indication information to the transmitting end.
The method according to claim 6, wherein before the receiving end determines the one-to-one correspondence, the method further includes:

Receiving, by the receiving end, a plurality of second optical signals sent by the transmitting end, where the plurality of second optical signals are obtained by optically modulating a plurality of second multi-carrier signals by the transmitting end, where the multiple The second multi-carrier signal is obtained by phase-compensating each sub-carrier signal of the first multi-carrier signal by using a preset phase compensation value of each of the plurality of preset phase compensation values;

The receiving end determines the one-to-one correspondence, including:

The receiving end calculates a performance indicator value of the plurality of subcarrier signals included in each of the plurality of second optical signals;

And the receiving end respectively determines an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal according to the calculated performance indicator value.
The method according to claim 7, wherein the receiving end respectively determines an optimal phase compensation value corresponding to each subcarrier signal in the first multicarrier signal according to the calculated performance indicator value, including :

And obtaining, by the receiving end, the subcarriers of each of the plurality of second optical signals from the calculated performance indicator values, for any one of the first multicarrier signals The performance indicator value of the signal;

Determining, by the receiving end, an optimal performance indicator value of the performance indicator value of the subcarrier signal in each second optical signal, and using a preset phase compensation value when the optimal performance indicator value is obtained The optimum phase compensation value corresponding to the subcarrier signal.
The method according to claim 8, wherein the performance index value of the plurality of subcarrier signals included in each of the second optical signals comprises a signal to noise ratio SNR and/or a bit error rate BER;

When the performance indicator value includes the SNR, the receiving end determines an optimal performance indicator value of the performance indicator values of the subcarrier signals in each of the second optical signals, and obtains the optimal performance indicator. The preset phase compensation value used as the value is the optimal phase compensation value corresponding to the subcarrier signal, where the receiving end determines the maximum SNR of the subcarrier signal in each of the second optical signals. And adopting a preset phase compensation value used when the SNR maximum value is obtained as an optimal phase compensation value corresponding to the subcarrier signal;

When the performance indicator value includes the BER, the receiving end determines an optimal performance indicator value of the performance indicator values of the subcarrier signals in each of the second optical signals, and obtains the optimal performance indicator. The preset phase compensation value used as the value is the optimal phase compensation value corresponding to the subcarrier signal, where the receiving end determines the maximum SNR of the subcarrier signal in each of the second optical signals. And the preset phase compensation value used when the SNR maximum value is obtained is taken as the optimal phase compensation value corresponding to the subcarrier signal.
The method according to any one of claims 7 to 9, wherein each of the plurality of preset phase compensation values is located in the same setting interval; when the plurality of presets When the phase compensation values are arranged in the order of increasing value, the difference between any two adjacent preset phase compensation values of the plurality of preset phase compensation values is a preset step size.
A dispersion compensation device, comprising:

a receiving module, configured to receive indication information sent by a receiving end of the optical fiber communication system, where the indication information includes multiple optimal phase compensation values and multiple subcarrier signals in the first multicarrier signal to be transmitted One-to-one correspondence of numbers;

a phase compensation module, configured to perform phase compensation on the plurality of subcarrier signals by using the plurality of optimal phase compensation values according to the one-to-one correspondence included in the indication information received by the receiving module, to obtain a second Multi-carrier signal;

An optical modulation module, configured to perform optical modulation on the second multi-carrier signal obtained by the phase compensation module to obtain a first optical signal;

And a sending module, configured to send the first optical signal modulated by the optical modulation module to the receiving end.
The device of claim 11 further comprising:

a determining module, configured to determine a plurality of preset phase compensation values before the receiving module receives the indication information sent by the receiving end;

The phase compensation module is further configured to perform phase compensation on each subcarrier signal in the first multicarrier signal by using each of the plurality of preset phase compensation values, to obtain a third Multi-carrier signal;

The optical modulation module is further configured to perform optical modulation on the third multi-carrier signal to obtain a second optical signal, where the second optical signal is used by the receiving end according to the multiple components included in the second optical signal. The performance indicator value of the carrier signal determines the one-to-one correspondence;

The sending module is further configured to send the second optical signal to the receiving end.
The apparatus according to claim 12, wherein the performance index value of the plurality of subcarrier signals included in the second optical signal comprises a signal to noise ratio SNR and/or a bit error rate BER;

And determining, by using the SNR, the preset phase compensation value used when the SNR of the subcarrier signal is the largest among the plurality of second optical signals, for any one of the first multicarrier signals Determining an optimal phase compensation value corresponding to the subcarrier signal; when the performance indicator value includes the BER, the preset phase compensation value used when the BER of the subcarrier signal is the smallest among the plurality of second optical signals is the sub The optimum phase compensation value corresponding to the carrier signal.
The device according to claim 12 or 13, wherein each of the plurality of preset phase compensation values is located in the same set interval; when the plurality of preset phases When the compensation values are arranged in the order of increasing numerical values, the difference between any two adjacent preset phase compensation values of the plurality of preset phase compensation values is a preset step size.
The device according to any one of claims 11 to 14, further comprising:

And an inverse Fourier transform module, configured to perform inverse Fourier transform on the second multicarrier signal before the optical modulation module optically modulates the second multicarrier signal.
A dispersion compensation device, comprising:

a determining module, configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system;

The indication information generating module is configured to generate indication information, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

And a sending module, configured to send the indication information to the transmitting end.
The device of claim 16 further comprising:

a receiving module, configured to receive, after the determining module determines the one-to-one correspondence, a plurality of second optical signals sent by the transmitting end, where the multiple second optical signals are multiple to the transmitting end The second multi-carrier signal is optically modulated, and the plurality of second multi-carrier signals are used by the transmitting end to each of the preset phase compensation values of the plurality of preset phase compensation values to the first multi-carrier respectively Each subcarrier signal in the signal is phase compensated;

When determining the one-to-one correspondence, the determining module is specifically configured to:

Calculating performance index values of the plurality of subcarrier signals included in each of the plurality of second optical signals; determining each of the first multicarrier signals according to the calculated performance indicator value The optimum phase compensation value corresponding to the carrier signal.
The apparatus according to claim 17, wherein said determining module determines an optimum phase compensation value corresponding to each subcarrier signal in said first multicarrier signal according to said calculated performance index value Specifically for:

Obtaining a performance index of the subcarrier signal of each of the plurality of second optical signals from the calculated performance indicator values for any one of the first multicarrier signals a value; determining an optimal value of the performance index value of the subcarrier signal in each of the second optical signals The performance indicator value, and the preset phase compensation value used when obtaining the optimal performance indicator value is used as the optimal phase compensation value corresponding to the subcarrier signal.
The apparatus according to claim 18, wherein the performance index value of the plurality of subcarrier signals included in each of the second optical signals comprises a signal to noise ratio SNR and/or a bit error rate BER;

When the performance indicator value includes the SNR, the determining module determines an optimal performance indicator value of the performance indicator value of the subcarrier signal in each of the second optical signals, and obtains the optimal performance. When the preset phase compensation value used in the index value is used as the optimal phase compensation value corresponding to the subcarrier signal, it is specifically used for:

Determining an SNR maximum value of the subcarrier signal in each of the second optical signals, and using a preset phase compensation value obtained when the SNR maximum value is obtained as an optimal phase compensation value corresponding to the subcarrier signal;

When the performance indicator value includes the BER, the determining module determines an optimal performance indicator value of the performance indicator value of the subcarrier signal in each of the second optical signals, and obtains the optimal performance. When the preset phase compensation value used in the index value is used as the optimal phase compensation value corresponding to the subcarrier signal, it is specifically used for:

Determining an SNR maximum value of the subcarrier signal in each of the second optical signals, and using a preset phase compensation value obtained when the SNR maximum value is obtained as an optimal phase compensation value corresponding to the subcarrier signal.
The apparatus according to any one of claims 17 to 19, wherein each of the plurality of preset phase compensation values is located in the same setting interval; when the plurality of presets When the phase compensation values are arranged in the order of increasing value, the difference between any two adjacent preset phase compensation values of the plurality of preset phase compensation values is a preset step size.
A dispersion compensation device, comprising:

a transceiver, configured to receive indication information sent by a receiving end of the optical fiber communication system, where the indication information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted;

a digital signal processor, configured to include the indication information received by the transceiver a one-to-one correspondence, phase compensation of the plurality of subcarrier signals by using the plurality of optimal phase compensation values to obtain a second multicarrier signal;

An electro-optic modulator for optically modulating the second multi-carrier signal obtained by the digital signal processor to obtain a first optical signal;

The transceiver is further configured to send the first optical signal modulated by the electro-optic modulator to the receiving end.
A dispersion compensation device, comprising:

a digital signal processor, configured to determine a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal to be transmitted by the transmitting end of the optical fiber communication system; and generate indication information, the indication The information includes a one-to-one correspondence between the plurality of optimal phase compensation values and the plurality of subcarrier signals in the first multicarrier signal;

And a transceiver, configured to send the indication information to the transmitting end.