Information transmission method, device and system based on coherent optical module

Abstract

The embodiment of the invention discloses an information transmission method, device and system based on a coherent optical module. A first device and a second device are arranged at the two ends of the communication system respectively, and the first device sends a first frame to the second device to inform the second device whether an LO optical signal in a local first coherent optical module of the first device is homologous with an optical signal to be sent or not; and the second device sends a second frame to the first device to inform the first device whether the LO optical signal in the local second coherent optical module of the second device is homologous with the optical signal to be sent. Through the above mode, the two ends of the communication system can inform the opposite end of whether the LO optical signals in the respective coherent optical modules and the optical signals to be sent are in the same source or not in a mode of mutually sending the frames, so that the coherent optical modules at the two ends can configure the light emitting frequencies for the respective light sources in a targeted manner; the coherent optical modules at the two ends can converge the frequency offset to an allowable range, and correct recovery of data can be guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication, and in particular to a method, apparatus and system for information transmission based on a coherent optical module. BACKGROUND

[0002] A coherent optical module refers to an optical module that uses coherent communication technology to realize data communication. Unlike a direct modulation / direct detection optical signal that only uses amplitude variation information of an optical signal to transmit data, both phase and amplitude information of a coherent optical signal are used to transmit data. The reception and demodulation of the coherent optical signal require mixing a local oscillator (LO) optical signal with the coherent optical signal to obtain phase information. In order to improve signal processing efficiency, reduce energy consumption and chip complexity, the coherent optical module requires that the frequency of the LO optical signal and the carrier frequency of the received coherent optical signal cannot have a large frequency deviation (referred to as frequency deviation) for clock and phase recovery of an electrical signal of coherent reception. If the frequency deviation is large, the coherent optical module can not recover data from the received signal.

[0003] In actual applications, the wavelengths of lasers provided by different manufacturers can be different, and therefore the coherent optical modules at both ends of a link can have the frequency deviation problem described above, and the frequency deviation can even exceed the standard allowed range. In the coherent optical module, an optical carrier used by an integrated coherent transmitter (ICT) and an LO optical signal used by an integrated coherent receiver (ICR) can be provided by the same light source or different light sources. At present, the frequency of the local LO optical signal is adjusted according to the actually received coherent optical signal for each type of coherent optical module, so as to minimize the frequency deviation. However, there can be multiple different scenarios based on the difference in the light source types of the coherent optical modules at both ends. In some scenarios, even if the current way of dealing with the frequency deviation is used, it cannot be guaranteed that the coherent optical modules at both ends can converge the frequency deviation to the allowed range, thereby affecting data recovery. SUMMARY

[0004] Embodiments of the present application provide a method, apparatus and system for information transmission based on a coherent optical module.

[0005] In a first aspect, the present application provides a method for information transmission based on a coherent optical module. Specifically, a first device sends a first frame to a second device, the first frame being used to indicate whether a local oscillator (LO) optical signal in a first coherent optical module and an optical signal to be transmitted are homologous. The first device is the first coherent optical module, or the first device is connected to the first coherent optical module. The first device receives a second frame sent by the second device, the second frame being used to indicate whether the LO optical signal in a second coherent optical module and the optical signal to be transmitted are homologous. The second device is the second coherent optical module, or the second device is connected to the second coherent optical module. It should be understood that if the LO optical signal and the optical signal to be transmitted are obtained from light emitted by the same light source, then the LO optical signal and the optical signal to be transmitted are homologous; if the LO optical signal and the optical signal to be transmitted are obtained from light emitted by different light sources, then the LO optical signal and the optical signal to be transmitted are not homologous.

[0006] In example 1, the first device is a first host, the second device is a second host, and the information transmission is performed between the first host and the second host. In example 2, the first device is a first host, the second device is a second coherent optical module, and the information transmission is performed between the first host and the second coherent optical module. In example 3, the first device is a first coherent optical module, the second device is a second host, and the information transmission is performed between the first coherent optical module and the second host. In example 4, the first device is a first coherent optical module, the second device is a second coherent optical module, and the information transmission is performed between the first coherent optical module and the second coherent optical module.

[0007] In this embodiment, the two ends of the communication system can inform the opposite end whether the LO optical signal and the optical signal to be transmitted in their respective coherent optical modules are homologous by sending frames to each other, so that the two ends of the coherent optical module can configure the light-emitting frequency for their respective light sources, and promote the two ends of the coherent optical module to converge the frequency offset to the allowed range, which is conducive to ensuring the correct recovery of data.

[0008] In some possible embodiments, in the coherent optical module using the first light source type, the LO optical signal and the optical signal to be transmitted are not homologous. In the coherent optical module using the second light source type, the LO optical signal and the optical signal to be transmitted are homologous. That is, the present application is compatible with optical modules of multiple different light source types, which enriches the application scenarios of the present application.

[0009] In some possible implementation manners, the first frame is further used to indicate whether there is a wavelength locking device in the light source of the first coherent light module, and the second frame is further used to indicate whether there is a wavelength locking device in the light source of the second coherent light module. The light source with the wavelength locking device has a smaller fluctuation range of the light emission frequency. That is, the first device and the second device can inform the peer of more information about the capability of the light source of the device in the capability advertisement stage, so as to facilitate the first device and the second device to negotiate a reasonable frequency adjustment mechanism more quickly, and facilitate the improvement of the convergence efficiency of the frequency offset.

[0010] In some possible implementation manners, the first frame is further used to indicate the accuracy of the light emission frequency of the light source in the first coherent light module, and the second frame is further used to indicate the accuracy of the light emission frequency of the light source in the second coherent light module. The accuracy of the light emission frequency of the light source is used to represent the fluctuation range of the light emission frequency of the light source. By extending the information transmitted by the first device and the second device in the capability advertisement stage, the first device and the second device can negotiate a reasonable frequency adjustment mechanism more quickly, and facilitate the improvement of the convergence efficiency of the frequency offset.

[0011] In some possible implementation manners, the method further includes: the first device sends a third frame to the second device. The third frame is used to request the second coherent light module to fix the frequency of the second LO optical signal or adjust the frequency of the second LO optical signal, and the third frame is further used to request the second coherent light module to fix the frequency of the second optical signal or adjust the frequency of the second optical signal. The second LO optical signal and the second optical signal are generated by the second coherent light module, and the second optical signal is used to send to the first coherent light module. In this implementation manner, after the capability advertisement is completed, the first device initiates negotiation with the second device according to the capabilities of both parties, so that the two parties can negotiate in a targeted manner to determine the frequency adjustment mechanism, and facilitate the improvement of the efficiency of negotiation and the efficiency of frequency offset convergence.

[0012] In some possible implementation manners, after the first device sends the third frame to the second device, the method further includes: the first device receives a fourth frame sent by the second device according to the third frame. The fourth frame is used to indicate whether to agree to the request of the third frame. That is, after receiving the request sent by the first device, the second device informs the first device whether to agree to the request of the first device, and the negotiation process of both parties is improved.

[0013] In some possible implementation manners, the fourth frame is used to indicate whether the second coherent light module fixes the frequency of the second LO optical signal or adjusts the frequency of the second LO optical signal, and the fourth frame is further used to indicate whether the second coherent light module fixes the frequency of the second optical signal or adjusts the frequency of the second optical signal. That is, the second device can inform the first device of the working mode selected by the local second coherent light module according to the request of the first device, so as to indicate whether to agree to the request of the first device in this way, and the implementation manners of the present solution are enriched.

[0014] In some possible implementation, the third frame is further configured to instruct the first coherent light module to fix or adjust a frequency of the first LO light signal, and the third frame is further configured to instruct the first coherent light module to fix or adjust a frequency of the first light signal. The first LO light signal and the first light signal are generated by the first coherent light module, and the first light signal is used to transmit to the second coherent light module. That is, the first device informs the second device of the working mode selected by the local first coherent light module through the third frame when initiating the request through the third frame, so that the second device can learn the working mode of the first coherent light module earlier, and the negotiation efficiency is improved.

[0015] In some possible implementation, the third frame is further configured to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. It should be understood that the acceptance capability of the coherent light module to the frequency offset is different for different signal modulation formats and different signal baud rates. Therefore, the first device and the second device are required to negotiate based on the same signal mode, so that the first device and the second device can communicate with each other, thereby ensuring the smooth negotiation.

[0016] In some possible implementation, after the first device transmits the third frame to the second device, the method further includes that the first device transmits a fifth frame to the second device. The fifth frame is configured to request the second coherent light module to fix or adjust a frequency of the second LO light signal, and the fifth frame is further configured to request the second coherent light module to fix or adjust a frequency of the second light signal, and the fifth frame is further configured to request the second coherent light module to transmit signals in a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate. In this implementation, the negotiation stage can be divided into multiple rounds of negotiation, that is, the frames transmitted in the first round of negotiation are all in the first signal modulation format and the first signal baud rate, and the frames transmitted in the second round of negotiation are all in the second signal modulation format and the second signal baud rate, so that the first device and the second device can complete the negotiation based on multiple signal modes, and the frequency offset convergence can be well achieved regardless of the actual signal mode adopted by the coherent light module.

[0017] In some possible implementation, the second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate. It should be understood that the higher the order of the signal modulation format and the higher the signal baud rate, the more stringent the requirement for the frequency offset. Therefore, the lower signal baud rate and the lower order signal modulation format can tolerate the transmission of information under a larger frequency offset, and the negotiation based on the lower signal baud rate and the lower order signal modulation format is more conducive to ensuring the smooth negotiation.

[0018] In some possible implementation, if the third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal, and the second device agrees to the request of the third frame, the absolute value of the difference between the frequency of the first light signal sent by the first coherent light module and the frequency of the adjusted second LO light signal is smaller than the absolute value of the difference between the frequency of the first light signal sent by the first coherent light module and the frequency of the unadjusted second LO light signal. That is, after the scheme of frequency adjustment is determined through negotiation, the coherent light module adjusts the frequency of the LO light signal generated by itself according to the actual received light signal frequency, so as to reduce the frequency offset between them.

[0019] In some possible implementation, in the first coherent light module, the first LO light signal and the first light signal are of different sources. In the second coherent light module, the second LO light signal and the second light signal are of the same source. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the method further includes that the first device receives a sixth frame sent by the second device, and the sixth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0020] In this implementation, the first coherent light module adopts an independent LO light source, and the second coherent light module adopts a shared LO light source. The first coherent light module has higher flexibility in adjusting the light emission frequency of the light source. Therefore, through negotiation, it is determined that the frequency of the second LO light signal and the frequency of the second light signal are first adjusted by the second coherent light module, and then the frequency of the first LO light signal is adjusted by the first coherent light module, so as to ensure that the coherent light modules at both ends can well realize frequency offset convergence.

[0021] In some possible implementation, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second light signal, the method further includes that the first device sends a fifth frame to the second device. The fifth frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal, and the fifth frame is further used to request the second coherent light module to transmit signals in a second signal mode, and the second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation between the first device and the second device based on the first signal mode is completed, the second round of negotiation between the first device and the second device based on the second signal mode is performed. No matter which signal mode is actually adopted by the coherent light module, frequency offset convergence can be well realized.

[0022] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from different sources. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second light signal, and the method further includes: the first device receives a seventh frame sent by the second device, and the seventh frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0023] In this implementation manner, both the first coherent light module and the second coherent light module use independent LO light sources, and both the first coherent light module and the second coherent light module can adjust the frequency of the LO light signal according to the frequency of the received light signal, so that the coherent light modules at both ends can well realize frequency offset convergence.

[0024] In some possible implementation manners, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second light signal, the method further includes: the first device sends a fifth frame to the second device. The fifth frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second light signal, and the fifth frame is further used to request the second coherent light module to transmit signals in a second signal mode, and the second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform a second round of negotiation based on the second signal mode, and no matter which signal mode is actually used by the coherent light modules, frequency offset convergence can be well realized.

[0025] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are from different sources; in the second coherent light module, the second LO light signal and the second light signal are from different sources. The method further includes: the first device negotiates with the second device to determine that the first coherent light module adjusts the frequency of the first LO light signal and the frequency of the first light signal first, and then the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal.

[0026] In this implementation manner, the first coherent light module and the second coherent light module use shared LO light sources, and therefore, it is determined through negotiation that the first coherent light module adjusts the light emission frequency of the light source first and the second coherent light module adjusts the light emission frequency of the light source later, so that the negotiation process can be smoothly performed.

[0027] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are homologous; in the second coherent light module, the second LO light signal and the second light signal are homologous. The light source of the first coherent light module has a wavelength locking device, the light source of the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. The third frame is used to request the second coherent light module to fix the frequency of the second LO light signal and the frequency of the second light signal, and the method further comprises: the first device receiving the eighth frame sent by the second device, the eighth frame being used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal. After the first coherent light module adjusts the frequency of the first LO light signal and the frequency of the first light signal according to the frequency of the second light signal, the method further comprises: the first device sending the ninth frame to the second device, the ninth frame being used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal.

[0028] In this implementation manner, although the first coherent light module and the second coherent light module both use the light source sharing the LO, the first coherent light module has a wavelength locking device, the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. Therefore, by negotiation, it is determined that the frequency of the first LO light signal and the frequency of the first light signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second light signal are adjusted by the second coherent light module, so that the coherent light modules at both ends can well realize the frequency offset convergence.

[0029] In some possible implementation manners, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, the first signal mode comprising at least one of a first signal modulation format and a first signal baud rate. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the method further comprises: the first device receiving the tenth frame sent by the second device. The tenth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal, and the tenth frame is further used to request the first coherent light module to transmit signals in a second signal mode, the second signal mode comprising at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation between the first device and the second device based on the first signal mode is completed, the second round of negotiation between the first device and the second device based on the second signal mode is performed, and no matter which signal mode is actually used by the coherent light modules, the frequency offset convergence can be well realized.

[0030] In a second aspect, the present application provides a method for information transmission based on a coherent light module. A first device generates a first frame and sends the first frame to a second device. The first frame is used to request the second coherent light module to fix or adjust the frequency of a second LO light signal and the frequency of a second light signal. The second LO light signal and the second light signal are generated by the second coherent light module, and the second light signal is used to send to the first coherent light module. In this embodiment, the first device initiates a negotiation with the second device, so that the two parties can determine a reasonable frequency adjustment mechanism through the negotiation, which is conducive to ensuring that the coherent light modules at both ends can well realize frequency offset convergence.

[0031] In some possible implementations, after the first device sends the first frame to the second device, the method further includes: the first device receives a second frame sent by the second device according to the first frame, and the second frame is used to indicate whether to agree with the request of the first frame. That is, after receiving the request sent by the first device, the second device informs the first device whether to agree with the request of the first device, which perfects the negotiation process of the two parties.

[0032] In some possible implementations, the second frame is used to indicate that the second coherent light module fixes or adjusts the frequency of the second LO light signal and the frequency of the second light signal. That is, the second device can inform the first device of the working mode selected by the local second coherent light module according to the request of the first device, so as to indicate whether to agree with the request of the first device in this way, which enriches the implementation manner of the present application.

[0033] In some possible implementations, the first frame is further used to indicate that the first coherent light module fixes or adjusts the frequency of a first LO light signal and the frequency of a first light signal. The first LO light signal and the first light signal are generated by the first coherent light module, and the first light signal is used to send to the second coherent light module. That is, the first device informs the second device of the working mode selected by the local first coherent light module through the first frame when initiating the request to the second device through the first frame, so that the second device can know the working mode of the first coherent light module earlier, which is conducive to improving the negotiation efficiency.

[0034] In some possible implementation manners, the first frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode comprises at least one of a first signal modulation format and a first signal baud rate. It should be understood that the acceptance capability of the coherent light module to the frequency offset is different for different signal modulation formats and different signal baud rates. Therefore, the first device and the second device are required to negotiate based on the same signal mode, so that the first device and the second device can communicate with each other, thereby ensuring the smooth negotiation.

[0035] In some possible implementation manners, after the first device sends the first frame to the second device, the method further comprises: the first device sends a third frame to the second device. The third frame is used to request the second coherent light module to fix or adjust the frequency of the second LO light signal, and is further used to request the second coherent light module to fix or adjust the frequency of the second light signal, and is further used to request the second coherent light module to transmit signals in a second signal mode. The second signal mode comprises at least one of a second signal modulation format and a second signal baud rate. In this implementation manner, the negotiation stage can be divided into multiple rounds of negotiation, that is, the frames transmitted in the first round of negotiation are all in the first signal modulation format and the first signal baud rate, and the frames transmitted in the second round of negotiation are all in the second signal modulation format and the second signal baud rate, so that the first device and the second device can complete the negotiation based on multiple signal modes, and the frequency offset convergence can be well achieved regardless of the actual signal mode adopted by the coherent light module.

[0036] In some possible implementation manners, the second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate. It should be understood that the higher the order of the signal modulation format and the higher the signal baud rate, the more stringent the requirement for the frequency offset, and therefore, the lower signal baud rate and the lower order signal modulation format can tolerate the transmission of information under a larger frequency offset, and the negotiation based on the lower signal baud rate and the lower order signal modulation format is more conducive to ensuring the smooth negotiation.

[0037] In some possible implementation manners, if the first frame is used to request the second coherent light module to adjust the frequency of the second LO light signal, and the second device agrees with the request of the first frame, the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the adjusted second LO light signal is less than the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the unadjusted second LO light signal. That is, after the frequency adjustment scheme is determined through negotiation, the coherent light module adjusts the frequency of the LO light signal generated by itself according to the actual received light signal frequency, so as to reduce the frequency offset between them.

[0038] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from the same source. The first frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the method further includes that the first device receives a fourth frame sent by the second device, and the fourth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0039] In this implementation manner, the first coherent light module adopts an independent-LO light source, the second coherent light module adopts a shared-LO light source, and the first coherent light module has higher flexibility in adjusting the light-emitting frequency of the light source. Therefore, by negotiation, it is determined that the frequency of the second LO light signal and the frequency of the second light signal are first adjusted by the second coherent light module, and then the frequency of the first LO light signal is adjusted by the first coherent light module, so that the coherent light modules at both ends can well achieve frequency offset convergence.

[0040] In some possible implementation manners, the first frame is further used to request the second coherent light module to transmit a signal in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second light signal, the method further includes that the first device sends a third frame to the second device. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal, and the third frame is further used to request the second coherent light module to transmit a signal in a second signal mode, and the second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform the second round of negotiation based on the second signal mode, and no matter which signal mode is actually adopted by the coherent light module, frequency offset convergence can be well achieved.

[0041] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from different sources. The first frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second light signal, and the method further includes that the first device receives a fifth frame sent by the second device, and the fifth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0042] In this embodiment, both the first coherent light module and the second coherent light module use independent LO light sources, and both the first coherent light module and the second coherent light module can adjust the frequency of the LO light signal according to the frequency of the received optical signal, so that the coherent light modules at both ends can well realize frequency offset convergence.

[0043] In some possible embodiments, the first frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second optical signal, the method further includes that the first device sends a third frame to the second device. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second optical signal, and the third frame is further used to request the second coherent light module to transmit signals in a second signal mode. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform a second round of negotiation based on the second signal mode, and no matter which signal mode the coherent light modules actually use, frequency offset convergence can be well realized.

[0044] In some possible embodiments, in the first coherent light module, the first LO light signal and the first optical signal are homologous; and in the second coherent light module, the second LO light signal and the second optical signal are homologous. The method further includes that the first device negotiates with the second device to determine that the frequency of the first LO light signal and the frequency of the first optical signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second optical signal are adjusted by the second coherent light module.

[0045] In this embodiment, both the first coherent light module and the second coherent light module use a shared LO light source, and therefore, it is necessary to determine through negotiation which of the first coherent light module and the second coherent light module first adjusts the light emission frequency of the light source and which of the first coherent light module and the second coherent light module later adjusts the light emission frequency of the light source, so that the negotiation process can be smoothly performed.

[0046] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are homologous; in the second coherent light module, the second LO light signal and the second light signal are homologous. The light source of the first coherent light module has a wavelength locking device, the light source of the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. The first frame is used to request the second coherent light module to fix the frequency of the second LO light signal and the frequency of the second light signal, and the method further comprises: the first device receiving the sixth frame sent by the second device, the sixth frame being used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal. After the first coherent light module adjusts the frequency of the first LO light signal and the frequency of the first light signal according to the frequency of the second light signal, the method further comprises: the first device sending the seventh frame to the second device, the seventh frame being used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal.

[0047] In this implementation manner, although the first coherent light module and the second coherent light module both use the light source sharing the LO, the first coherent light module has a wavelength locking device, the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. Therefore, by negotiation, it is determined that the frequency of the first LO light signal and the frequency of the first light signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second light signal are adjusted by the second coherent light module, so that the coherent light modules at both ends can well realize the frequency offset convergence.

[0048] In some possible implementation manners, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, the first signal mode comprising at least one of a first signal modulation format and a first signal baud rate. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the method further comprises: the first device receiving the tenth frame sent by the second device. The tenth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal, and the tenth frame is further used to request the first coherent light module to transmit signals in a second signal mode, the second signal mode comprising at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation between the first device and the second device based on the first signal mode is completed, the second round of negotiation between the first device and the second device based on the second signal mode is performed, and no matter which signal mode is actually used by the coherent light modules, the frequency offset convergence can be well realized.

[0049] In a third aspect, the present application provides a communication device, which is the first device in any of the embodiments of the first aspect. The communication device comprises a sending unit and a receiving unit. The sending unit sends a first frame to a second device, the first frame being used to indicate whether the LO light signal and the to-be-sent light signal in the first coherent light module are homologous. The first device is the first coherent light module, or the first device is connected to the first coherent light module. The receiving unit receives a second frame sent by the second device, the second frame being used to indicate whether the LO light signal and the to-be-sent light signal in the second coherent light module are homologous. The second device is the second coherent light module, or the second device is connected to the second coherent light module.

[0050] In some possible embodiments, in the coherent light module of the first light source type, the LO light signal and the to-be-sent light signal are not homologous. In the coherent light module of the second light source type, the LO light signal and the to-be-sent light signal are homologous. That is, the present application is compatible with light modules of multiple different light source types, enriching the application scenarios of the present application.

[0051] In some possible embodiments, the first frame is further used to indicate whether there is a wavelength locking device in the light source of the first coherent light module, and the second frame is further used to indicate whether there is a wavelength locking device in the light source of the second coherent light module. The light source with the wavelength locking device has a smaller fluctuation range of the light emission frequency. That is, the first device and the second device can inform the opposite end of more information related to the capability of the light source thereof in the capability announcement stage, so as to facilitate the first device and the second device to negotiate a reasonable frequency adjustment mechanism more quickly, and to improve the convergence efficiency of the frequency offset.

[0052] In some possible embodiments, the first frame is further used to indicate the precision of the light emission frequency of the light source in the first coherent light module, and the second frame is further used to indicate the precision of the light emission frequency of the light source in the second coherent light module. The precision of the light emission frequency of the light source is used to represent the fluctuation range of the light emission frequency of the light source. By expanding the information transmitted by the first device and the second device in the capability announcement stage, the first device and the second device can negotiate a reasonable frequency adjustment mechanism more quickly, and the convergence efficiency of the frequency offset can be improved.

[0053] In some possible implementation manners, the sending unit is further configured to send a third frame to the second device. The third frame is used to request the second coherent light module to fix or adjust a frequency of the second LO light signal, and the third frame is further used to request the second coherent light module to fix or adjust a frequency of the second light signal. The second LO light signal and the second light signal are generated by the second coherent light module, and the second light signal is used to send to the first coherent light module. In this implementation manner, after the capability advertisement is completed, the first device initiates negotiation with the second device according to the capabilities of both sides, so that the two devices can perform negotiation in a targeted manner to determine the frequency adjustment mechanism, and the efficiency of negotiation and the efficiency of frequency offset convergence are improved.

[0054] In some possible implementation manners, after the sending unit sends the third frame to the second device, the receiving unit is further configured to receive a fourth frame sent by the second device according to the third frame. The fourth frame is used to indicate whether to agree with the request of the third frame. That is, after receiving the request sent by the first device, the second device informs the first device whether to agree with the request of the first device, and the negotiation process of both sides is improved.

[0055] In some possible implementation manners, the fourth frame is used to indicate that the second coherent light module fixes or adjusts the frequency of the second LO light signal, and the fourth frame is further used to indicate that the second coherent light module fixes or adjusts the frequency of the second light signal. That is, the second device can inform the first device of the working mode selected by the local second coherent light module according to the request of the first device, so as to indicate whether to agree with the request of the first device in this way, and the implementation manners of the present solution are enriched.

[0056] In some possible implementation manners, the third frame is further used to indicate that the first coherent light module fixes or adjusts a frequency of the first LO light signal, and the third frame is further used to indicate that the first coherent light module fixes or adjusts a frequency of the first light signal. The first LO light signal and the first light signal are generated by the first coherent light module, and the first light signal is used to send to the second coherent light module. That is, the first device informs the second device of the working mode selected by the local first coherent light module at the same time when the third frame is used to initiate the request to the second device, so that the second device can know the working mode of the first coherent light module earlier, and the negotiation efficiency is improved.

[0057] In some possible implementation, the third frame is further configured to request the second coherent light module to transmit signals in a first signal mode, the first signal mode comprising at least one of a first signal modulation format and a first signal baud rate. It should be understood that the acceptance of frequency offset by the coherent light module is different for different signal modulation formats and different signal baud rates. Therefore, the first device and the second device are required to negotiate based on the same signal mode so that the first device and the second device can communicate with each other, thereby ensuring the smooth negotiation.

[0058] In some possible implementation, after the sending unit sends the third frame to the second device, the sending unit is further configured to send a fifth frame to the second device. The fifth frame is configured to request the second coherent light module to fix or adjust the frequency of the second LO light signal, fix or adjust the frequency of the second light signal, and transmit signals in a second signal mode. The second signal mode comprises at least one of a second signal modulation format and a second signal baud rate. In this implementation, the negotiation stage can be divided into multiple rounds of negotiation, that is, the frames transmitted in the first round of negotiation are all in the first signal modulation format and the first signal baud rate, and the frames transmitted in the second round of negotiation are all in the second signal modulation format and the second signal baud rate, so that the first device and the second device can complete the negotiation based on multiple signal modes, and the frequency offset convergence can be well achieved regardless of the actual signal mode adopted by the coherent light module.

[0059] In some possible implementation, the second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate. It should be understood that the higher the order of the signal modulation format and the higher the signal baud rate, the more stringent the requirement for the frequency offset, and therefore, a lower signal baud rate and a lower order signal modulation format can be allowed to transmit information under a larger frequency offset, and the negotiation based on the lower signal baud rate and the lower order signal modulation format is more conducive to ensuring the smooth negotiation.

[0060] In some possible implementation, if the third frame is configured to request the second coherent light module to adjust the frequency of the second LO light signal, and the second device agrees to the request of the third frame, the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the adjusted second LO light signal is less than the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the unadjusted second LO light signal. That is, after the scheme of frequency adjustment is determined through negotiation, the coherent light module is required to adjust the frequency of the LO light signal generated by itself according to the actual received light signal frequency, so as to reduce the frequency offset between them.

[0061] In some possible implementation, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from the same source. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the receiving unit is further configured to receive a sixth frame sent by the second device, and the sixth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0062] In this implementation, the first coherent light module adopts an independent-LO light source, and the second coherent light module adopts a shared-LO light source. The first coherent light module has higher flexibility in adjusting the light-emitting frequency of the light source. Therefore, by negotiation, it is determined that the frequency of the second LO light signal and the frequency of the second light signal are first adjusted by the second coherent light module, and then the frequency of the first LO light signal is adjusted by the first coherent light module, so that the coherent light modules at both ends can well achieve frequency offset convergence.

[0063] In some possible implementation, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second light signal, the sending unit is further configured to send a fifth frame to the second device. The fifth frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal, and the fifth frame is further used to request the second coherent light module to transmit signals in a second signal mode, and the second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation based on the first signal mode between the first device and the second device is completed, the second round of negotiation based on the second signal mode is performed between the first device and the second device. No matter which signal mode is actually adopted by the coherent light module, frequency offset convergence can be well achieved.

[0064] In some possible implementation, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from different sources. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second light signal, and the receiving unit is further configured to receive a seventh frame sent by the second device, and the seventh frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0065] In this embodiment, both the first coherent light module and the second coherent light module use independent LO light sources, and both the first coherent light module and the second coherent light module can adjust the frequency of the LO light signal according to the frequency of the received optical signal, so that the coherent light modules at both ends can well realize frequency offset convergence.

[0066] In some possible embodiments, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode, the first signal mode including at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second optical signal, the sending unit is further used to send a fifth frame to the second device. The fifth frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second optical signal, and the fifth frame is further used to request the second coherent light module to transmit signals in a second signal mode, the second signal mode including at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation between the first device and the second device based on the first signal mode is completed, the second round of negotiation between the first device and the second device based on the second signal mode is performed, and no matter which signal mode the coherent light module actually uses, frequency offset convergence can be well realized.

[0067] In some possible embodiments, in the first coherent light module, the first LO light signal and the first optical signal are homologous; and in the second coherent light module, the second LO light signal and the second optical signal are homologous. The communication device further includes a processing unit, which is used to negotiate with the second device to determine that the frequency of the first LO light signal and the frequency of the first optical signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second optical signal are adjusted by the second coherent light module.

[0068] In this embodiment, both the first coherent light module and the second coherent light module use a shared LO light source, so that it is determined through negotiation which of the first coherent light module and the second coherent light module first adjusts the light-emitting frequency of the light source and which of the first coherent light module and the second coherent light module later adjusts the light-emitting frequency of the light source, so that the negotiation process can be smoothly performed.

[0069] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are homologous; in the second coherent light module, the second LO light signal and the second light signal are homologous. The light source of the first coherent light module has a wavelength locking device, the light source of the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. The third frame is used to request the second coherent light module to fix the frequency of the second LO light signal and the frequency of the second light signal, and the receiving unit is further configured to receive an eighth frame sent by the second device. The eighth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal. After the first coherent light module adjusts the frequency of the first LO light signal and the frequency of the first light signal according to the frequency of the second light signal, the method further comprises that the first device sends a ninth frame to the second device. The ninth frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal.

[0070] In this implementation manner, the first coherent light module and the second coherent light module both use the light source sharing the LO, but the first coherent light module has a wavelength locking device, the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emitting frequency of the light source in the first coherent light module is higher than the accuracy of the light emitting frequency of the light source in the second coherent light module. Therefore, it is determined by negotiation that the frequency of the first LO light signal and the frequency of the first light signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second light signal are adjusted by the second coherent light module, so that the frequency offset convergence of both ends of the coherent light module can be well realized.

[0071] In some possible implementation manners, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode. The first signal mode comprises at least one of a first signal modulation format and a first signal baud rate. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the receiving unit is further configured to receive a tenth frame sent by the second device. The tenth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal, and the tenth frame is further used to request the first coherent light module to transmit signals in a second signal mode. The second signal mode comprises at least one of a second signal modulation format and a second signal baud rate. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform the second round of negotiation based on the second signal mode. No matter which signal mode is actually used by the coherent light module, the frequency offset convergence can be well realized.

[0072] In a fourth aspect, the present application provides a communication device, which is the first device in any of the above-mentioned embodiments of the second aspect. The communication device comprises a processing unit and a sending unit. The processing unit generates a first frame, and the sending unit sends the first frame to a second device. The first frame is used to request the second coherent light module to fix or adjust the frequency of a second LO light signal, and the first frame is also used to request the second coherent light module to fix or adjust the frequency of a second light signal. The second LO light signal and the second light signal are generated by the second coherent light module, and the second light signal is used to send to the first coherent light module. In this embodiment, the first device initiates negotiation with the second device, so that the two parties can determine a reasonable frequency adjustment mechanism through negotiation, which is conducive to ensuring that the coherent light modules at both ends can well realize frequency offset convergence.

[0073] In some possible implementation manners, the communication device further comprises a receiving unit. After the sending unit sends the first frame to the second device, the receiving unit is configured to receive a second frame sent by the second device according to the first frame. The second frame is used to indicate whether to agree with the request of the first frame. That is to say, after receiving the request sent by the first device, the second device informs the first device whether to agree with the request of the first device, which perfects the negotiation process of the two parties.

[0074] In some possible implementation manners, the second frame is used to indicate that the second coherent light module fixes or adjusts the frequency of the second LO light signal, and the second frame is also used to indicate that the second coherent light module fixes or adjusts the frequency of the second light signal. That is to say, the second device can inform the first device of the working mode selected by the local second coherent light module according to the request of the first device, so as to indicate whether to agree with the request of the first device in this way, which enriches the implementation manners of the present application.

[0075] In some possible implementation manners, the first frame is further used to indicate that the first coherent light module fixes or adjusts the frequency of a first LO light signal, and the first frame is also used to indicate that the first coherent light module fixes or adjusts the frequency of a first light signal. The first LO light signal and the first light signal are generated by the first coherent light module, and the first light signal is used to send to the second coherent light module. That is to say, the first device informs the second device of the working mode selected by the local first coherent light module through the first frame at the same time when initiating the request to the second device through the first frame, so that the second device can know the working mode of the first coherent light module earlier, which is conducive to improving the negotiation efficiency.

[0076] In some possible implementation, the first frame is further configured to request the second coherent light module to transmit signals in a first signal mode, the first signal mode comprising at least one of a first signal modulation format and a first signal baud rate. It should be understood that the acceptance of frequency offset by the coherent light module is different for different signal modulation formats and different signal baud rates. Therefore, the first device and the second device are required to negotiate based on the same signal mode so that the first device and the second device can communicate with each other, thereby ensuring the smooth negotiation.

[0077] In some possible implementation, after the sending unit sends the first frame to the second device, the sending unit is further configured to send a third frame to the second device. The third frame is configured to request the second coherent light module to fix or adjust the frequency of the second LO light signal, and to request the second coherent light module to fix or adjust the frequency of the second light signal, and to request the second coherent light module to transmit signals in a second signal mode. The second signal mode comprises at least one of a second signal modulation format and a second signal baud rate. In this implementation, the negotiation stage can be divided into multiple rounds of negotiation, that is, the frames transmitted in the first round of negotiation are all in the first signal modulation format and the first signal baud rate, and the frames transmitted in the second round of negotiation are all in the second signal modulation format and the second signal baud rate, so that the first device and the second device can complete the negotiation based on multiple signal modes, and the frequency offset convergence can be well achieved regardless of the actual signal mode adopted by the coherent light module.

[0078] In some possible implementation, the second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate. It should be understood that the higher the order of the signal modulation format and the higher the signal baud rate, the more stringent the requirement for the frequency offset, and therefore, a lower signal baud rate and a lower order signal modulation format can be allowed to transmit information under a larger frequency offset, and the negotiation based on the lower signal baud rate and the lower order signal modulation format is more conducive to ensuring the smooth negotiation.

[0079] In some possible implementation, if the first frame is configured to request the second coherent light module to adjust the frequency of the second LO light signal, and the second device agrees to the request of the first frame, the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the adjusted second LO light signal is less than the absolute value of the difference between the frequency of the first light signal transmitted by the first coherent light module and the frequency of the unadjusted second LO light signal. That is, after the scheme of frequency adjustment is determined through negotiation, the coherent light module is required to adjust the frequency of the LO light signal generated by itself according to the actual received light signal frequency, so as to reduce the frequency offset between them.

[0080] In some possible implementation, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from the same source. The first frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the receiving unit is further configured to receive a fourth frame sent by the second device, and the fourth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0081] In this implementation, the first coherent light module adopts an independent-LO light source, and the second coherent light module adopts a shared-LO light source, and the first coherent light module has higher flexibility in adjusting the light-emitting frequency of the light source. Therefore, by negotiation, it is determined that the frequency of the second LO light signal and the frequency of the second light signal are first adjusted by the second coherent light module, and then the frequency of the first LO light signal is adjusted by the first coherent light module, so that the coherent light modules at both ends can well realize frequency offset convergence.

[0082] In some possible implementation, the first frame is further used to request the second coherent light module to transmit signals in a first signal mode, and the first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second light signal, the sending unit is further configured to send a third frame to the second device. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal, and the third frame is further used to request the second coherent light module to transmit signals in a second signal mode, and the second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first round of negotiation between the first device and the second device based on the first signal mode is completed, the second round of negotiation between the first device and the second device based on the second signal mode is performed, and no matter which signal mode is actually adopted by the coherent light module, frequency offset convergence can be well realized.

[0083] In some possible implementation, in the first coherent light module, the first LO light signal and the first light signal are from different sources. In the second coherent light module, the second LO light signal and the second light signal are from different sources. The first frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second light signal, and the receiving unit is further configured to receive a fifth frame sent by the second device, and the fifth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and fix the frequency of the first light signal.

[0084] In this embodiment, both the first coherent light module and the second coherent light module use independent LO light sources, and both the first coherent light module and the second coherent light module can adjust the frequency of the LO light signal according to the frequency of the received optical signal, so that the coherent light modules at both ends can well realize frequency offset convergence.

[0085] In some possible embodiments, the first frame is further used to request the second coherent light module to transmit signals in a first signal mode, the first signal mode including at least one of a first signal modulation format and a first signal baud rate. After the first coherent light module adjusts the frequency of the first LO light signal according to the frequency of the second optical signal, the sending unit is further configured to send a third frame to the second device. The third frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and fix the frequency of the second optical signal, and the third frame is further used to request the second coherent light module to transmit signals in a second signal mode, the second signal mode including at least one of a second signal modulation format and a second signal baud rate. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform a second round of negotiation based on the second signal mode, and no matter which signal mode the coherent light modules actually use, frequency offset convergence can be well realized.

[0086] In some possible embodiments, in the first coherent light module, the first LO light signal and the first optical signal are homologous; and in the second coherent light module, the second LO light signal and the second optical signal are homologous. The processing unit is further configured to negotiate with the second device to determine that the frequency of the first LO light signal and the frequency of the first optical signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second optical signal are adjusted by the second coherent light module.

[0087] In this embodiment, both the first coherent light module and the second coherent light module use shared LO light sources, and therefore, it is necessary to determine, through negotiation, which of the first coherent light module and the second coherent light module first adjusts the light emission frequency of the light source and which of the first coherent light module and the second coherent light module later adjusts the light emission frequency of the light source, so that the negotiation process can be smoothly performed.

[0088] In some possible implementation manners, in the first coherent light module, the first LO light signal and the first light signal are homologous; in the second coherent light module, the second LO light signal and the second light signal are homologous. The light source of the first coherent light module has a wavelength locking device, the light source of the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emission frequency of the light source in the first coherent light module is higher than the accuracy of the light emission frequency of the light source in the second coherent light module. The first frame is used to request the second coherent light module to fix the frequency of the second LO light signal and the frequency of the second light signal, and the receiving unit is further configured to receive a sixth frame sent by the second device. The sixth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal. After the first coherent light module adjusts the frequency of the first LO light signal and the frequency of the first light signal according to the frequency of the second light signal, the method further includes that the first device sends a seventh frame to the second device. The seventh frame is used to request the second coherent light module to adjust the frequency of the second LO light signal and the frequency of the second light signal.

[0089] In this embodiment, although the first coherent light module and the second coherent light module both use the light source sharing the LO, the first coherent light module has a wavelength locking device, the second coherent light module does not have a wavelength locking device, and / or the accuracy of the light emission frequency of the light source in the first coherent light module is higher than the accuracy of the light emission frequency of the light source in the second coherent light module. Therefore, it is determined by negotiation that the frequency of the first LO light signal and the frequency of the first light signal are first adjusted by the first coherent light module, and then the frequency of the second LO light signal and the frequency of the second light signal are adjusted by the second coherent light module, so that the coherent light modules at both ends can well realize the frequency offset convergence.

[0090] In some possible implementation manners, the third frame is further used to request the second coherent light module to transmit signals in a first signal mode. The first signal mode includes at least one of a first signal modulation format and a first signal baud rate. After the second coherent light module adjusts the frequency of the second LO light signal and the frequency of the second light signal according to the frequency of the first light signal, the receiving unit is further configured to receive a tenth frame sent by the second device. The tenth frame is used to request the first coherent light module to adjust the frequency of the first LO light signal and the frequency of the first light signal, and the tenth frame is further used to request the first coherent light module to transmit signals in a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate. That is, after the first device and the second device complete the first round of negotiation based on the first signal mode, the first device and the second device perform the second round of negotiation based on the second signal mode. No matter which signal mode is actually used by the coherent light module, the frequency offset convergence can be well realized.

[0091] In a fifth aspect, an embodiment of the present application provides a chip. The chip includes a processor. The processor is configured to execute the method in any of the embodiments of the first aspect and the second aspect.

[0092] In a sixth aspect, an embodiment of the present application provides a communication device, the communication device comprising a control circuit and an interface circuit, the interface circuit being configured to transceive signals, and the control circuit being configured to perform the method according to any one of the embodiments of the first aspect and the second aspect.

[0093] In a seventh aspect, an embodiment of the present application provides a communication system, the communication system comprising a first device and a second device, the first device being configured to perform the method according to any one of the embodiments of the first aspect and the second aspect.

[0094] In an eighth aspect, an embodiment of the present application provides a computer-readable storage medium, the computer-readable storage medium storing instructions, the instructions being configured to cause a computer to perform the method according to any one of the embodiments of the first aspect and the second aspect.

[0095] In a ninth aspect, an embodiment of the present application provides a computer program product, the computer program product comprising program instructions, the program instructions being configured to cause a computer to perform the method according to any one of the embodiments of the first aspect and the second aspect. BRIEF DESCRIPTION OF DRAWINGS

[0096] Figure 1 A schematic diagram of a communication system to which an embodiment of the present application is applied;

[0097] Figure 2 A schematic diagram of a coherent light module with a frequency offset in an embodiment of the present application;

[0098] Figure 3 A first schematic diagram of a coherent light module in an embodiment of the present application;

[0099] Figure 4 A second schematic diagram of a coherent light module in an embodiment of the present application;

[0100] Figure 5 A schematic diagram of a possible light source structure in an embodiment of the present application;

[0101] Figure 6 A comparison diagram of a light-emitting frequency fluctuation range in an embodiment of the present application;

[0102] Figure 7 A flowchart of a method of information transmission based on a coherent light module in an embodiment of the present application;

[0103] Figure 8 A schematic diagram of a frequency offset acceptance degree based on different signal modulation formats and signal baud rates in an embodiment of the present application;

[0104] FIG. 9(a) is a schematic diagram of a first scenario of information transmission between a device 1 and a device 2 in an embodiment of the present application;

[0105] Fig. 9(b) is a schematic diagram of a second scenario of information transmission between device 1 and device 2 in the embodiment of the present application;

[0106] Fig. 9(c) is a schematic diagram of a third scenario of information transmission between device 1 and device 2 in the embodiment of the present application;

[0107] Fig. 9(d) is a schematic diagram of a fourth scenario of information transmission between device 1 and device 2 in the embodiment of the present application;

[0108] Figure 10 Fig. 10 is a schematic diagram of a structure of a first subframe in a superframe in the embodiment of the present application;

[0109] Figure 11 Fig. 11 is a schematic diagram of a protocol stack layer model architecture applicable in the embodiment of the present application;

[0110] Figure 12 Fig. 12 is a schematic diagram of application scenario 1 in the embodiment of the present application;

[0111] Figure 13 Fig. 13 is a schematic diagram of an implementation based on application scenario 1 in the embodiment of the present application;

[0112] Figure 14 Fig. 14 is a schematic diagram of application scenario 2 in the embodiment of the present application;

[0113] Figure 15 Fig. 15 is a schematic diagram of an implementation based on application scenario 2 in the embodiment of the present application;

[0114] Figure 16 Fig. 16 is a schematic diagram of application scenario 3 in the embodiment of the present application;

[0115] Figure 17 Fig. 17 is a schematic diagram of an implementation based on application scenario 3 in the embodiment of the present application;

[0116] Figure 18 Fig. 18 is a schematic diagram of a structure of a communication device in the embodiment of the present application;

[0117] Figure 19 Fig. 19 is a schematic diagram of another structure of a communication device in the embodiment of the present application. DETAILED DESCRIPTION

[0118] The embodiment of the present application provides a kind of information transmission method, device and system based on coherent optical module, the two ends of communication system can be informed to the other end by sending frame to each other whether LO light signal in respective coherent optical module and the light signal to be sent are homologous, to make the coherent optical module of two ends can be configured to emit light frequency for respective light source, promote the coherent optical module of two ends can all converge to the allowed range of frequency deviation, it is advantageous to guarantee the correct recovery of data.

[0119] Figure 1 This is a schematic diagram of a communication system used in an embodiment of this application. Figure 1 As shown, the communication system includes a transmitting device 01, a transmitting processing module 02, a channel transmission medium 03, a receiving processing module 04, and a receiving device 05. Taking a data center network as an example, the transmitting device 01 and the receiving device 05 can be devices such as switches, routers, or servers. The transmitting device 01 is also referred to as the host at the transmitting end, and the receiving device 05 is also referred to as the host at the receiving end. The host can also be called a host chip or host module. In the implementation of this application, the host can be a server. When the host is a server, the optical module in this embodiment can be connected to the server in a pluggable manner. For ease of description, the following description will use the transmitting device 01 and the receiving device 05 as hosts. Exemplarily, the host includes, but is not limited to, a switch chip or a physical layer (PHY) chip, such as an application-specific integrated circuit (ASIC) chip. The channel transmission medium 03 can be an optical fiber. The transmitting device 01 and the transmitting processing module 02 can be connected via a channel, and the receiving device 05 and the receiving processing module 04 can also be connected via a channel. The type of this channel depends on the types of the transmitting and receiving processing modules 02 and 04. The channel type includes an electrical interface, such as an attachment unit interface (AUI) and a common electrical interface (or Common Electrical I / O, CEI). Alternatively, the channel can also be called an electrical link. For example, the channel can be a physical medium such as a printed circuit board (PCB) trace, copper cable, or connector. The transmitting and receiving processing modules 02 and 04 can be optical modules, electrical modules, or other modules that process data during transmission. It should be understood that the transmitting device 01, transmitting processing module 02, channel transmission medium 03, receiving processing module 04, and receiving device 05 in this communication system can all support bidirectional transmission or unidirectional transmission; specific limitations are not specified here.

[0120] In the embodiments of the present application, the sending processing module 02 and the receiving processing module 04 can both be coherent optical modules. The coherent optical module includes a light source, an integrated coherent transmitter (ICT), an integrated coherent receiver (ICR), a micro controller unit (MCU), and the like. The ICT includes a modulator and the like, and the ICR includes a mixer and the like. As an example, an optical digital signal processor (oDSP) chip is arranged inside the coherent optical module, which can be referred to as a digital coherent optical (DCO) module. As another example, the oDSP chip is arranged outside the coherent optical module, and the oDSP chip is also not arranged inside the host, that is, the oDSP chip is placed independently of the coherent optical module and the host, which can be referred to as an analog coherent optical (ACO) module. For ease of introduction, the coherent optical module integrated with the oDSP chip is taken as an example for description below.

[0121] It should be understood that the coherent optical module refers to an optical module that uses coherent communication technology to realize data communication. Unlike the direct modulation and direct detection optical signal that only uses the amplitude change information of the optical signal to transmit data, the phase and amplitude information of the coherent optical signal are both used to transmit data. The reception and demodulation of the coherent optical signal need to use a local oscillator (LO) optical signal to mix with the coherent optical signal to obtain the phase information. In the coherent optical module, the LO optical signal is provided by a continuous wave light source. After the LO optical signal and the coherent optical signal are mixed by an optical mixer, the mixed signal is converted into an electrical signal by a balanced detector. The oDSP chip performs clock data recovery (CDR) on the electrical signal, and then performs digital signal processing (DSP) to compensate for link impairments and the like. For example, the coherent optical module can be an 800LR optical module.

[0122] Figure 2 An example of the coherent optical module with frequency offset in the embodiments of the present application is shown in FIG. 1. As shown in FIG. 1, the sending processing module 02 and the receiving processing module 04 are both coherent optical modules. The sending processing module 02 includes an oDSP chip, an ICT, an ICR, and the like. The receiving processing module 04 also includes an oDSP chip, an ICT, an ICR, and the like. The ICT includes a modulator and the like, and the ICR includes a mixer and the like. The oDSP chip is arranged inside the coherent optical module, which can be referred to as a DCO module. The oDSP chip is arranged outside the coherent optical module, and the oDSP chip is also not arranged inside the host, that is, the oDSP chip is placed independently of the coherent optical module and the host, which can be referred to as an ACO module. Figure 2As shown in the figure, the frequency of the LO optical signal generated by the coherent optical module is denoted as f LO, the frequency of the optical signal received by the coherent optical module is denoted as f Sig, and there can be a frequency deviation between f LO and f Sig, which is also referred to as frequency offset. If the frequency offset is large, the coherent optical module can not be able to recover data from the received signal, and therefore, the coherent optical module needs to adjust the frequency of the light source to reduce the frequency offset so that the frequency offset is within an allowable range.

[0123] It should be noted that in the coherent optical module, the optical carrier used by the ICT and the LO optical signal used by the ICR can be provided by the same light source, or can be provided by different light sources respectively. That is, the coherent optical module can have two different types of light sources, which will be introduced below.

[0124] Figure 3 The figure is a first structure diagram of the coherent optical module in the embodiment of the present application. As shown in the figure, Figure 3 The coherent optical module includes a light source 1 and a light source 2. The light source 1 is used to provide an optical carrier for the integrated coherent transmitter, and the light source 2 is used to provide an optical carrier for the integrated coherent receiver. The optical carrier provided by the light source 2 can be referred to as an LO optical signal. As can be seen, the optical carrier used by the integrated coherent transmitter and the LO optical signal used by the integrated coherent receiver are provided by different light sources respectively, that is, the LO optical signal and the optical signal to be transmitted are different sources, Figure 3 The light source type of the coherent optical module shown in the figure can be referred to as an independent LO light source.

[0125] Figure 4 The figure is a second structure diagram of the coherent optical module in the embodiment of the present application. As shown in the figure, Figure 4 The coherent optical module includes one light source, and the optical carrier output by the light source is transmitted to the integrated coherent transmitter after passing through a power splitter. Another part of the optical carrier is transmitted to the integrated coherent receiver, and the optical carrier transmitted to the integrated coherent receiver can be referred to as an LO optical signal. As can be seen, the optical carrier used by the integrated coherent transmitter and the LO optical signal used by the integrated coherent receiver are provided by the same light source, that is, the LO optical signal and the optical signal to be transmitted are the same source, Figure 4 The light source type of the coherent optical module shown in the figure can be referred to as a shared LO light source.

[0126] It should be noted that, as Figure 3As shown in FIG. 4, the controller of the coherent light module is configured to control the light source to adjust the light emitting frequency of the light source, and the controller and the oDSP chip can exchange information. The device controller of the host and the PHY chip can exchange information, and the device controller of the host and the controller of the coherent light module can also exchange information. For example, the controller of the coherent light module can be a micro controller unit (MCU), and the device controller of the host can be a central processing unit (CPU). The MCU and the CPU are connected through a management interface, and the coherent light module can report its light source type to the host through the management interface. For example, the management interface can be an inter-integrated circuit (IIC, I2C) interface, and the management protocol based on the management interface can be a common management interface specification (CMIS).

[0127] In the transmission direction, the PHY chip sends an electrical signal to the oDSP chip, for example, the electrical signal can be a non-return to zero (NRZ) signal or a pulse amplitude modulation 4-level (PAM4) signal, etc. The oDSP chip can generate a quadrature phase shift keying (QPSK) signal or a 16-ary quadrature amplitude modulation (16QAM) signal, etc. according to the electrical signal sent by the PHY chip. The integrated coherent transmitter modulates the electrical signal from the oDSP chip onto the optical carrier to obtain the optical signal 1, and transmits the optical signal 1 through the channel transmission medium. In the receiving direction, the integrated coherent receiver receives the optical signal 2 through the channel transmission medium, and processes the optical signal 2 through mixing with the LO optical signal to convert the optical signal 2 into an electrical signal. The oDSP chip further processes the electrical signal through CDR and DSP, etc. and sends it to the PHY chip.

[0128] Figure 5 A possible light source structure in the embodiments of the present application is shown in FIG. 3. As shown in FIG. 3, the light source of the coherent light module can be a laser diode (LD) or a supercontinuum light source (SC). Figure 5As shown, the light source includes a driver and a laser, and the driver is used to drive the laser to emit light. For example, the controller of the coherent light module can specifically control the driver of the light source to adjust the light emitting frequency of the laser. Alternatively, the light source can also include a wave locker device, wherein the light source with the wave locker device has higher accuracy of light emitting frequency and higher cost. It should be noted that the specific type of the laser is not limited in the present application, for example, the laser can be a distributed feedback (DFB) laser, a distributed bragg reflector (DBR) laser or an external cavity laser, etc.

[0129] Figure 6 A comparison diagram of the light emitting frequency fluctuation range in the embodiment of the present application is shown in FIG. 3. As shown in FIG. 3, the light emitting frequency fluctuation range of the light source without the wave locker device is ±Δf1, and the light emitting frequency fluctuation range of the light source with the wave locker device is ±Δf2. It can be seen that Δf1<Δf2, and the light emitting frequency of the light source with the wave locker device has higher accuracy. Figure 6

[0130] In the embodiment of the present application, the two ends of the communication system can inform the opposite end whether the LO light signal and the to-be-transmitted light signal in the respective coherent light module are homologous by transmitting frames to each other, so that the two ends of the coherent light module can configure the light emitting frequency for the respective light source, so as to make the two ends of the coherent light module converge the frequency offset to the allowed range. The information transmission method based on the coherent light module passed by the embodiment of the present application will be introduced below.

[0131] Figure 7 A flowchart of the information transmission method based on the coherent light module in the embodiment of the present application is shown in FIG. 4. As shown in FIG. 4, the information transmission method based on the coherent light module in the embodiment of the present application includes the following steps. Figure 7 ​As shown in the embodiments of this application, the two ends of the communication system are referred to as device 1 and device 2, respectively. For example, device 1 and device 2 are located at the two ends of an optical fiber. The end where device 1 is located includes a coherent optical module 1. For example, device 1 can be a coherent optical module 1, or device 1 can also be a host 1 electrically connected to the coherent optical module 1. The end where device 2 is located includes a coherent optical module 2. For example, device 2 can be a coherent optical module 2, or device 2 can also be a host 2 electrically connected to the coherent optical module 2. For ease of description, in some embodiments below, coherent optical module 1 can also be referred to as the local coherent optical module at the end where device 1 is located, and coherent optical module 2 can also be referred to as the local coherent optical module at the end where device 2 is located. The LO optical signal generated by coherent optical module 1 is called LO optical signal 1, and the optical signal transmitted by coherent optical module 1 is called TX optical signal 1. The LO optical signal generated by coherent optical module 2 is called LO optical signal 2, and the optical signal transmitted by coherent optical module 2 is called TX optical signal 2. Specifically, the information transmission process between device 1 and device 2 can be divided into a capability announcement phase and a negotiation phase.

[0132] During the capability notification phase, device 1 sends frame 1 to device 2. Frame 1 indicates whether the LO optical signal 1 and TX optical signal 1 in coherent optical module 1 are from the same source. Device 2 sends frame 2 to device 1, indicating whether the LO optical signal 2 and TX optical signal 2 in coherent optical module 2 are from the same source. In this way, device 1 and device 2 can determine the specific procedure of the negotiation phase based on the information they receive. It should be understood that this application does not limit the specific information carried in frames 1 and 2, as long as it serves to inform the other end of its capabilities. Several possible implementation methods are described below using frame 1 as an example. As an example, one bit in frame 1 is used to indicate the type of light source in coherent optical module 1. For example, a bit value of 1 indicates the above... Figure 3 The independent LO light source shown indicates that the LO light signal 1 and the TX light signal 1 are not from the same source; a bit value of 0 indicates the above. Figure 4 The shared LO light source shown indicates that LO light signal 1 and TX light signal 1 are from the same source. As another example, frame 1 carries at least one parameter, the value of which indicates whether LO light signal 1 and TX light signal 1 are from the same source.

[0133] In some possible scenarios, during the capability notification phase, the frames transmitted between device 1 and device 2 can carry additional information to further distinguish the different light sources in the coherent optical modules. For example, frame 1 may also indicate whether the light source of coherent optical module 1 has a wavelength locking device, and frame 2 may also indicate whether the light source of coherent optical module 2 has a wavelength locking device. As another example, frame 1 may also indicate the accuracy of the emission frequency of the light source in coherent optical module 1, and frame 2 may also indicate the accuracy of the emission frequency of the light source in coherent optical module 2.

[0134] The following Table 1 gives the definition of the value of each field in the frame in the capability announcement stage. For the field of the light source type, the bit value of 1 represents the independent LO light source as shown above, and the bit value of 0 represents the shared LO light source as shown above. Figure 3 Figure 4 For the field of whether there is a wavelength locking device in the LO light source, the LO light source refers to the light source generating the LO optical signal, the bit value of 0 represents that there is a wavelength locking device in the LO light source, and the bit value of 1 represents that there is no wavelength locking device in the LO light source. For the field of the emission frequency accuracy of the LO light source, the bit value of 0 represents that the emission frequency of the LO light source is high accuracy, and the bit value of 1 represents that the emission frequency of the LO light source is low accuracy; or the field can also include multiple bits for representing the specific value (unit: GHz) of the emission frequency of the LO light source.

[0135] Table 1

[0136]

[0137] In the negotiation stage, the device 1 sends a frame 3 to the device 2, the frame 3 is used to initiate a request to the device 2, the content of the request includes requesting the coherent light module 2 to fix or adjust the frequency of the LO optical signal 2 and requesting the coherent light module 2 to fix or adjust the frequency of the TX optical signal 2; the device 2 sends a frame 4 to the device 1 according to the frame 3, the frame 4 is used to indicate whether the device 2 agrees to the request initiated by the device 1. Correspondingly, in the negotiation stage, the device 2 sends a frame 5 to the device 1, the frame 5 is used to initiate a request to the device 1, the content of the request includes requesting the coherent light module 1 to fix or adjust the frequency of the LO optical signal 1 and requesting the coherent light module 1 to fix or adjust the frequency of the TX optical signal 1; the device 1 sends a frame 6 to the device 1 according to the frame 5, the frame 6 is used to indicate whether the device 1 agrees to the request initiated by the device 2. It should be understood that the negotiation process initiated by the device 1 to the device 2 is synchronous with the negotiation process initiated by the device 2 to the device 1.

[0138] ​In some possible implementation manners, the device 1 can also inform the device 2 of its decision by sending the frame 3, for example, the frame 3 is used to indicate that the coherent light module 1 fixes or adjusts the frequency of the LO light signal 1 and the coherent light module 1 fixes or adjusts the frequency of the TX light signal 1. Similarly, the device 2 can also inform the device 1 of its decision by sending the frame 5, for example, the frame 5 is used to indicate that the coherent light module 2 fixes or adjusts the frequency of the LO light signal 2 and the coherent light module 2 fixes or adjusts the frequency of the TX light signal 2.

[0139] In one possible scenario, one bit in the frame 4 sent by the device 2 to the device 1 is used to indicate whether to agree with the request initiated by the device 1, for example, the bit is valued as 0 to indicate disagreement, and the bit is valued as 1 to indicate agreement. Similarly, one bit in the frame 6 sent by the device 1 to the device 2 is used to indicate whether to agree with the request initiated by the device 2, for example, the bit is valued as 0 to indicate disagreement, and the bit is valued as 1 to indicate agreement. If the device 2 agrees with the request of the device 1, and the device 1 also agrees with the request of the device 2, the negotiation is considered successful.

[0140] In another possible scenario, the frame 4 sent by the device 2 to the device 1 is used to indicate that the coherent light module 2 fixes or adjusts the frequency of the LO light signal 2 and the coherent light module 2 fixes or adjusts the frequency of the TX light signal 2. If the content indicated by the frame 4 is consistent with the content requested by the frame 3, it indicates that the device 2 agrees with the request initiated by the device 1; otherwise, it indicates that the device 2 disagrees with the request initiated by the device 1. Similarly, the frame 6 sent by the device 1 to the device 2 is used to indicate that the coherent light module 1 fixes or adjusts the frequency of the LO light signal 1 and the coherent light module 1 fixes or adjusts the frequency of the TX light signal 1. If the content indicated by the frame 6 is consistent with the content requested by the frame 5, it indicates that the device 1 agrees with the request initiated by the device 2; otherwise, it indicates that the device 1 disagrees with the request initiated by the device 2. It should be noted that, in actual applications, the transmission process of the frame 3, the frame 4, the frame 5 and the frame 6 can be repeated N times, and if the content transmitted by the frame 3, the frame 4, the frame 5 and the frame 6 does not change after being repeated N times, the negotiation is considered successful.

[0141] It should be noted that after the device 1 and the device 2 negotiate successfully, the corresponding coherent optical module starts to adjust the light emitting frequency of the light source. Taking the case that the device 2 agrees with the request of the device 1 as an example, the coherent optical module 2 adjusts the frequency of the LO optical signal 2 according to the frequency of the received TX optical signal 1, so as to reduce the frequency offset between the TX optical signal 1 and the LO optical signal 2, thereby enabling the frequency offset between the TX optical signal 1 and the LO optical signal 2 to be adjusted to the allowed frequency offset range, and realizing the convergence of the frequency offset. Specifically, the oDSP chip of the coherent optical module 2 estimates the frequency offset df according to the frequency of the TX optical signal 1 and the frequency of the LO optical signal 2, and sends the frequency offset df to the controller (for example, MCU) of the coherent optical module 2, and the controller adjusts the light emitting frequency of the light source according to the frequency offset df. The following introduces several possible ways to adjust the light emitting frequency of the light source.

[0142] As an example, |df| is within the frequency adjustment capability range of the light source, the controller controls the light source to adjust the light emitting frequency, and the frequency adjustment amount is df, so as to eliminate the frequency offset. As another example, |df| is beyond the frequency adjustment capability of the light source, the controller controls the light source to adjust the light emitting frequency, and the frequency adjustment amount can be the maximum value within the frequency adjustment capability range of the light source, so as to reduce the frequency offset as much as possible. As yet another example, the controller controls the light source to adjust the light emitting frequency, which can be adjusted to the position in one step, or can be adjusted to the position in a step-by-step multi-step manner, for example, the controller determines the direction of frequency adjustment, the step size of frequency adjustment and the number of steps of frequency adjustment according to df. As still another example, if the estimated frequency offset df is within the allowed frequency offset range, the light emitting frequency of the light source can not be adjusted.

[0143] Figure 8 The following is a schematic diagram of the frequency offset tolerance based on different signal modulation formats and signal baud rates in the embodiments of the present application. As shown in Figure 8 For the coherent optical signal, the higher the order of the signal modulation format and the higher the signal baud rate, the more stringent the requirement for the frequency offset. For example, in a 100 gigabits per second (gigabits per second, Gbps) coherent scenario, a DP-QPSK signal with a signal baud rate of 27.9525 GBd is used, and in a 400 Gbps coherent scenario, a DP-16QAM signal with a signal baud rate of 59.84375 GBd is used. The 400 Gbps coherent scenario is more sensitive to the frequency offset than the 100 Gbps coherent scenario. Therefore, if the coherent optical link is initialized, the use of a lower signal baud rate and a lower order signal modulation format can tolerate the transmission of information at a larger frequency offset, support the adjustment and optimization of the configuration of the coherent optical module from a poor initial condition, and ultimately achieve better link performance.

[0144] In some possible scenarios, the negotiation phase can be specifically divided into multiple rounds of negotiation. For example, the transmission processes of frame 3, frame 4, frame 5, and frame 6 in the above embodiment can be regarded as the first round of negotiation based on the first signal mode, that is, the frames transmitted in the first round of negotiation are all in the first signal modulation format and the first signal baud rate. Correspondingly, the frames transmitted in the first round of negotiation all carry information of the first signal mode, which is used to request the other end to transmit signals in the first signal mode. After the first round of negotiation ends and the first round of adjustment of the light-emitting frequency of the light source is completed, it can be considered that the frequency offset convergence based on the first signal mode is completed, and the device 1 and the device 2 further start the second round of negotiation based on the second signal mode, that is, the frames transmitted in the second round of negotiation are all in the second signal modulation format and the second signal baud rate. Correspondingly, the frames transmitted in the second round of negotiation all carry information of the second signal mode, which is used to request the other end to transmit signals in the second signal mode. It should be understood that the second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate, which is equivalent to upgrading from the first signal mode to the second signal mode. In actual application, the specific division of the negotiation phase into several rounds of negotiation depends on the target signal mode actually used by the coherent optical module for service transmission. In the above manner, M rounds of negotiation are performed until the target signal mode is upgraded, and the Mth round of negotiation and the Mth round of adjustment of the light-emitting frequency of the light source are completed, and it can be considered that the frequency offset convergence based on the target signal mode is completed.

[0145] The process of the second round of negotiation is similar to that of the first round of negotiation. For example, the device 1 sends frame 7 to the device 2, and frame 7 is used to initiate a request to the device 2, the content of the request including requesting the coherent light module 2 to fix or adjust the frequency of the LO optical signal 2 and requesting the coherent light module 2 to fix or adjust the frequency of the TX optical signal 2. The device 2 sends frame 8 to the device 1 according to frame 7, and frame 8 is used to indicate whether the device 2 agrees with the request initiated by the device 1. Correspondingly, the device 2 sends frame 9 to the device 1, and frame 9 is used to initiate a request to the device 1, the content of the request including requesting the coherent light module 1 to fix or adjust the frequency of the LO optical signal 1 and requesting the coherent light module 1 to fix or adjust the frequency of the TX optical signal 1. The device 1 sends frame 10 to the device 1 according to frame 9, and frame 10 is used to indicate whether the device 1 agrees with the request initiated by the device 2.

[0146] It should be understood that if the information of the signal mode carried by the frames sent by the device 1 and the device 2 is different, the two parties should send signals in the higher-level signal mode. For example, the frame sent by the device 1 to the device 2 carries information of the first signal mode, and the frame sent by the device 2 to the device 1 carries information of the second signal mode, so the device 1 and the device 2 both send signals based on the second signal mode.

[0147] The following table 2 gives the definition of the value of each field in the frame in the negotiation phase. For the field of whether to adjust the local TX optical signal, the bit value of 0 means to adjust the frequency of the local TX optical signal, and the bit value of 1 means to fix (not to adjust) the frequency of the local TX optical signal. For the field of whether to adjust the local LO optical signal, the bit value of 0 means to adjust the frequency of the local LO optical signal, and the bit value of 1 means to fix (not to adjust) the frequency of the local LO optical signal. For the field of whether to request the peer TX optical signal to adjust, the bit value of 0 means to request to adjust the frequency of the peer TX optical signal, and the bit value of 1 means to request to fix (not to adjust) the frequency of the peer TX optical signal. For the field of whether to request the peer LO optical signal to adjust, the bit value of 0 means to request to adjust the frequency of the peer LO optical signal, and the bit value of 1 means to request to fix (not to adjust) the frequency of the peer LO optical signal. For the field of signal modulation format, the bit value of 00 means QPSK, the bit value of 01 means 16QAM, the bit value of 10 means 32QAM, and the bit value of 11 means 64QAM. For the field of signal baud rate, the bit value of 00 means 27GBd, the bit value of 01 means 59GBd, the bit value of 10 means 132GBd, and the bit value of 11 means 236GBd.

[0148] Table 2

[0149]

[0150] It should be noted that the oDSP chip of the coherent optical module participates in the above-mentioned Figure 7 The oDSP chip can synchronize the obtained information to the controller (for example, MCU) of the coherent optical module. According to the information synchronized by the oDSP chip, the controller can update the value of the register itself, so that the controller can better cooperate with the oDSP chip to realize the adjustment of the light source emitting frequency. Moreover, after the controller completes the adjustment of the light source emitting frequency, the oDSP chip can also synchronize the information of the completed adjustment. The following table 3 gives the definition of the value of each field in the register. For the field of whether the capability announcement is completed, the bit value of 0 means that the capability announcement has been completed, and the bit value of 1 means that the capability announcement has not been completed. For the field of whether to start the negotiation, the bit value of 0 means not to start the negotiation, and the bit value of 1 means to start the negotiation. For the field of whether to adjust the light source, the bit value of 0 means not to adjust the light source, and the bit value of 1 means to adjust the light source.

[0151] Table 3

[0152]

[0153] Figure 9(a) is a schematic diagram of a first scenario of information transmission between device 1 and device 2 in embodiments of the present application. As shown in Figure 9(a), device 1 is host 1 and device 2 is host 2, and the information transmission is between host 1 and host 2. In a possible implementation, taking the example of host 1 sending frames to host 2, the frame structure used by host 1 to send information to coherent light module 1 is different from the frame structure used by coherent light module 1 to send information to coherent light module 2. For example, coherent light module 1 reads information from frame A from host 1, coherent light module 1 generates frame B according to the read information and sends frame B to coherent light module 2, coherent light module 2 generates frame C according to the information read from frame B, and coherent light module 2 sends frame C to host 2. Generally, frame A and frame B carry the same information, and if coherent light module 1 finds that the information in frame A is incorrect, it can rewrite the information and then generate frame B. In another possible implementation, taking the example of host 1 sending frames to host 2, the frame structure used by host 1 to send information to coherent light module 1 is the same as the frame structure used by coherent light module 1 to send information to coherent light module 2. For example, coherent light module 1 reads information from frame A from host 1, if the information in frame A is correct, it transmits frame A to coherent light module 2 and further to host 2; if the information in frame A is incorrect, it rewrites the information and then sends frame A to coherent light module 2 and further to host 2. It should be understood that the way host 2 sends frames to host 1 is similar to the way host 1 sends frames to host 2, which will not be described here.

[0154] Figure 9(b) is a schematic diagram of a second scenario of information transmission between device 1 and device 2 in embodiments of the present application. As shown in Figure 9(a), device 1 is host 1 and device 2 is coherent light module 2, and the information transmission is between host 1 and coherent light module 2. In a possible implementation, the frame structure used by host 1 to transmit information to coherent light module 1 is different from the frame structure used by coherent light module 1 to transmit information to coherent light module 2. In another possible implementation, the frame structure used by host 1 to transmit information to coherent light module 1 is the same as the frame structure used by coherent light module 1 to transmit information to coherent light module 2.

[0155] Fig. 9(c) is a schematic diagram of a third scenario of information transmission between device 1 and device 2 in the embodiments of the present application. As shown in Fig. 9(c), device 1 is coherent light module 1, and device 2 is host 2. Information transmission is performed between coherent light module 1 and host 2. In a possible implementation, the frame structure used for information transmission between host 2 and coherent light module 2 is different from the frame structure used for information transmission between coherent light module 1 and coherent light module 2. In another possible implementation, the frame structure used for information transmission between host 2 and coherent light module 2 is the same as the frame structure used for information transmission between coherent light module 1 and coherent light module 2.

[0156] Fig. 9(d) is a schematic diagram of a fourth scenario of information transmission between device 1 and device 2 in the embodiments of the present application. As shown in Fig. 9(d), device 1 is coherent light module 1, and device 2 is coherent light module 2. Information transmission is performed between coherent light module 1 and coherent light module 2. In this scenario, the above-mentioned Figure 7 processes can be implemented by the two coherent light modules without the help of the host, and the coherent light modules themselves can adjust the light emitting frequency of the light source. Therefore, the scenario shown in Fig. 9(d) is more conducive to improving the efficiency of capability announcement and negotiation, and has better application value.

[0157] It should be noted that the frame used for information transmission between device 1 and device 2 in the above-mentioned Figure 7 processes can have various implementation forms, which will be introduced below.

[0158] In a possible implementation, a frame different from the frame used for service transmission can be used to transmit information in the capability announcement stage and the negotiation stage shown in Fig. 9(a). For example, this frame can be a differential Manchester encoding (DME) frame, and the information introduced in the above-mentioned embodiments can be carried by one or more bits in the base page or next page of the DME frame. It should be understood that the frame used in this implementation can be generated by the host or by the coherent light module. Figure 7 Figure 7 In another possible implementation, the reserved position in the frame used for service transmission can be used to carry the information introduced in the above-mentioned embodiments.

[0159] Fig. 10 is a schematic diagram of a structure of the first subframe in a superframe in the embodiments of the present application. As shown in Fig. 10, the first subframe in the superframe can be used to carry the information introduced in the above-mentioned embodiments. Figure 7 Figure 10 Fig. 11 is a schematic diagram of a structure of the first subframe in a superframe in the embodiments of the present application. As shown in Fig. 11, the first subframe in the superframe can be used to carry the information introduced in the above-mentioned embodiments. Figure 10 Figure 7 ​​​The information introduced in the embodiments shown. Among them, the first sub-frame in the super-frame includes Q pilot symbols, T training symbols, N FAW frame alignment word symbols (FAW symbols), N RES reserved symbols and a plurality of payload symbols. Specifically, the N RES reserved symbols can be used to carry Figure 7 information introduced in the embodiments shown. It should be understood that the frame used in this embodiment is generated by a coherent optical module.

[0160] Figure 11 A protocol stack layer model architecture diagram applicable to the embodiments of the present application. The protocol stack layer model is the protocol stack layer of Ethernet. Ethernet is a set of standards defined by the Institute of Electrical and Electronics Engineers (IEEE) 802 standard organization, which involves network, interface and physical layer technology. The one related to the embodiments of the present application can be the Ethernet physical layer, and its protocol stack layer can refer to Figure 11 . As Figure 11 shown, the model architecture is a network interconnection model, which defines a seven-layer framework of network interconnection, from bottom to top, which is physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer.

[0161] Ethernet is in the data link layer and physical layer in the open system interconnection (OSI) reference model. As Figure 11 shown, the data link layer includes two sub-layers: the logical link control (LLC) sub-layer and the medium access control (MAC) sub-layer responsible for parsing and assembling Ethernet frames.

[0162] As Figure 11As shown, the physical layer can include a physical medium dependent (PMD) sublayer, a physical medium attachment (PMA) sublayer, and a physical coding sublayer (PCS). There is also a reconciliation sublayer (RS) between the PCS and the MAC sublayer. There is a certain gigabit media independent interface (GMII) between the RS and the PCS, such as an XGMII, 25GMII, 50GMII, etc. The PMD sublayer is connected with a medium through a medium dependent interface (MDI), which can be a cable or an optical fiber, etc. It should be understood that the embodiments of the present application can be implemented in the PCS sublayer. For example, if the embodiments of the present application are implemented in the first subframe of the superframe as shown in Figure 10 the flow as shown in Figure 7 For the step of generating the superframe in the PCS sublayer, the embodiments of the present application add the information introduced in the embodiment as shown in 7 to the first subframe of the superframe.

[0163] It should be noted that after the capability announcement stage as shown in Figure 7 is completed, the capabilities of device 1 and device 2 are determined, and the subsequent negotiation process is determined. Based on the types of light sources used by coherent light module 1 and coherent light module 2, there are three application scenarios. Application scenario 1: both the coherent light module 1 locally in device 1 and the coherent light module 2 locally in device 2 use independent LO light sources. Application scenario 2: the coherent light module 1 locally in device 1 uses an independent LO light source, and the coherent light module 2 locally in device 2 uses a shared LO light source. Application scenario 3: both the coherent light module 1 locally in device 1 and the coherent light module 2 locally in device 2 use a shared LO light source.

[0164] It should be understood that for the above three application scenarios, the specific process of negotiation between device 1 and device 2 will also be different. Specifically, for application scenario 1, both coherent light modules on both sides adjust the light emitting frequency of their own LO light sources according to the received optical signal to achieve frequency offset convergence. For application scenarios 2 and 3, one side of the coherent light module adjusts the light emitting frequency of the light source first, and the other side of the coherent light module adjusts the light emitting frequency of the light source to follow, to ensure that both sides of the coherent light module achieve frequency offset convergence, wherein the coherent light module that adjusts the light emitting frequency first can be regarded as a master, and the coherent light module that adjusts the light emitting frequency later can be regarded as a slave.

[0165] In application scenario 2, since the coherent light module 2 adopts the light source sharing the LO, the flexibility of the coherent light module 2 to adjust the light emitting frequency of the light source is relatively low, so the coherent light module 2 adjusts the light emitting frequency of the light source first, that is, the coherent light module 2 is the master and the coherent light module 1 is the slave.

[0166] In application scenario 3, since the coherent light module 1 and the coherent light module 2 both adopt the light source sharing the LO, it is further needed to determine which coherent light module is the master and which coherent light module is the slave through other information. For example, the coherent light module 1 has a wavelength locking device and the coherent light module 2 does not have a wavelength locking device, so the coherent light module 1 is the master and the coherent light module 2 is the slave. For another example, the light emitting frequency precision of the light source in the coherent light module 1 is higher than that of the light source in the coherent light module 2, so the coherent light module 1 is the master and the coherent light module 2 is the slave. For another example, if the wavelength locking device and the light emitting frequency precision of the light source cannot distinguish the coherent light module 1 and the coherent light module 2, the coherent light module 1 and the coherent light module 2 can each generate a set of random numbers and inform the opposite end of the random numbers generated by each, so as to determine the master and the slave through the size of the random numbers. For example, if the random number generated by the coherent light module 1 is greater than the random number generated by the coherent light module 2, the coherent light module 1 is the master and the coherent light module 2 is the slave. The random number can be a set of seed bits, for example, the random number is obtained by assigning values to 5 bits.

[0167] According to the above introduction, in order to ensure that the negotiation process in each application scenario is completed as soon as possible, for the above Figure 7 The frame sent in the negotiation stage in the embodiment shown in the table can be extended to carry information in the frame. Table 4 gives a specific example. For example, one bit in the frame is used to indicate whether to determine the master and the slave, where a bit value of 0 indicates that the master and the slave do not need to be determined, and a bit value of 1 indicates that the master and the slave need to be determined. For another example, one bit in the frame is used to indicate whether the local coherent light module is the master or the slave, where a bit value of 0 indicates that the local coherent light module is the slave, and a bit value of 1 indicates that the local coherent light module is the master. For another example, a plurality of seed bits in the frame are used to indicate the random number generated by the local coherent light module.

[0168] Table 4

[0169]

[0170] Based on Table 4, it should be understood that for application scenario 1, it is not necessary to determine the master and slave; the corresponding bit values ​​in the frames transmitted between device 1 and device 2 are 0, which is equivalent to both coherent optical modules acting as masters. For application scenario 2, it is necessary to determine the master and slave; the corresponding bit values ​​in the frames transmitted between device 1 and device 2 are 1. Since coherent optical module 2 is the master and coherent optical module 1 is the slave, the corresponding bit values ​​in the frames sent by device 1 to device 2 are 0, and the corresponding bit values ​​in the frames sent by device 2 to device 1 are 1. For application scenario 3, it is necessary to determine the master and slave. The corresponding bit values ​​in the frames transmitted between device 1 and device 2 are set to 1. As an example, coherent optical module 1 has a wavelength locking device, while coherent optical module 2 does not. Coherent optical module 1 is the master, and coherent optical module 2 is the slave. The corresponding bit values ​​in the frames sent from device 1 to device 2 are set to 1, and the corresponding bit values ​​in the frames sent from device 2 to device 1 are set to 0. As another example, the emission frequency accuracy of the light source in coherent optical module 1 is higher than that of the light source in coherent optical module 2. Coherent optical module 1 is the master, and coherent optical module 2 is the slave. In the frames sent from device 1 to device 2, the corresponding bit value is 1, and in the frames sent from device 2 to device 1, the corresponding bit value is 0. As another example, coherent optical module 1 and coherent optical module 2 cannot be distinguished by the wavelength locking device and the emission frequency accuracy of the light source. The frames sent from device 1 to device 2 carry the first set of random numbers, and the frames sent from device 2 to device 1 carry the second set of random numbers. If the first set of random numbers is greater than the second set of random numbers, then it is determined that coherent optical module 1 is the master and coherent optical module 2 is the slave.

[0171] The specific negotiation processes between device 1 and device 2 in the three application scenarios described above will be introduced in detail below. It should be understood that, for ease of explanation, the following embodiments only describe one round of negotiation based on one signal mode. The multi-round negotiation process based on multiple signal modes can be flexibly extended based on this.

[0172] Figure 12 This is a schematic diagram of application scenario 1 in the embodiments of this application. For example... Figure 12 As shown, both coherent optical module 1 and coherent optical module 2 use independent LO light sources, corresponding to the application scenario 1 mentioned above. Figure 13 This is a schematic diagram illustrating an implementation method based on application scenario 1 in this application. For example... Figure 13 As shown, the implementation method based on application scenario 1 includes the following steps.

[0173] During the capability notification phase, the frames transmitted between device 1 and device 2 include at least one bit. Taking at least one bit used to indicate the local light source type as an example, referring to Table 1, a bit value of 0 indicates a shared LO light source, and a bit value of 1 indicates an independent LO light source. Device 1 sends frame 1-1(1) to device 2, indicating that the local coherent optical module 1 of device 1 uses an independent LO light source. Device 2 sends frame 2-1(1) to device 1, indicating that the local coherent optical module 2 of device 2 uses an independent LO light source.

[0174] During the negotiation phase, the frames transmitted between device 1 and device 2 include at least four bits. The meanings of these four bits are: whether the local TX optical signal is adjusted, whether the local LO optical signal is adjusted, requesting adjustment of the peer's TX optical signal, and requesting adjustment of the peer's LO optical signal. The information corresponding to the different values ​​of these four bits can be found in Table 2. Device 1 sends frame 1-2 (1, 0, 1, 0) to device 2, indicating that the frequency of TX optical signal 1 is fixed and the frequency of LO optical signal 1 is adjusted, and also requesting that the frequency of TX optical signal 2 be fixed and the frequency of LO optical signal 2 be adjusted. Device 2, based on frame 1-2 (1, 0, 1, 0), sends frame 2-3 (1, 0, 1, 0) to device 1, indicating that the frequency of TX optical signal 2 is fixed and the frequency of LO optical signal 2 is adjusted, and also requesting that the frequency of TX optical signal 1 be fixed and the frequency of LO optical signal 1 be adjusted. In other words, device 2 agrees to device 1's request. Correspondingly, device 2 sends frame 2-2 (1, 0, 1, 0) to device 1, indicating that the frequency of the TX optical signal 2 is fixed and the frequency of the LO optical signal 2 is adjusted, and also requesting that the frequency of the TX optical signal 1 be fixed and the frequency of the LO optical signal 1 be adjusted; device 1 sends frame 1-3 (1, 0, 1, 0) to device 2 based on frame 2-2 (1, 0, 1, 0), indicating that the frequency of the TX optical signal 1 is fixed and the frequency of the LO optical signal 1 is adjusted, and also requesting that the frequency of the TX optical signal 2 be fixed and the frequency of the LO optical signal 2 be adjusted, that is, device 1 agrees to device 2's request. Furthermore, coherent optical module 1 can adjust the frequency of the LO optical signal 1 according to the frequency of the TX optical signal 2 to converge the frequency offset; coherent optical module 2 can adjust the frequency of the LO optical signal 2 according to the frequency of the TX optical signal 1 to converge the frequency offset.

[0175] Figure 14 This is a schematic diagram of application scenario 2 in the embodiments of this application. For example... Figure 14 As shown, coherent optical module 1 uses an independent LO light source, while coherent optical module 2 uses a shared LO light source, corresponding to application scenario 2 mentioned above. Figure 15 This is a schematic diagram illustrating an implementation method based on application scenario 2 in this application. For example... Figure 15 As shown, the implementation method based on application scenario 2 includes the following steps.

[0176] During the capability notification phase, the frames transmitted between device 1 and device 2 include at least one bit. Taking at least one bit used to indicate the local light source type as an example, referring to Table 1, a bit value of 0 indicates a shared LO light source, and a bit value of 1 indicates an independent LO light source. Device 1 sends frame 1-1(1) to device 2, indicating that the local coherent optical module 1 of device 1 uses an independent LO light source. Device 2 sends frame 2-1(0) to device 1, indicating that the local coherent optical module 2 of device 2 uses a shared LO light source.

[0177] During the negotiation phase, the frames transmitted between device 1 and device 2 include at least four bits. The meanings of these four bits are: whether the local TX optical signal is adjusted, whether the local LO optical signal is adjusted, requesting adjustment of the peer's TX optical signal, and requesting adjustment of the peer's LO optical signal. The information corresponding to different values ​​of these four bits can be found in Table 2. Device 1 sends frame 1-2 (1, 1, 0, 0) to device 2, indicating that the frequencies of TX optical signal 1 and LO optical signal 1 are fixed, and also requesting adjustment of the frequencies of TX optical signal 2 and LO optical signal 2. Device 2, based on frame 1-2 (1, 1, 0, 0), sends frame 2-3 (0, 0, 1, 1) to device 1, indicating that the frequencies of TX optical signal 2 and LO optical signal 2 are adjusted, and also requesting that the frequencies of TX optical signal 1 and LO optical signal 1 be fixed. In other words, device 2 agrees to device 1's request. Correspondingly, device 2 sends frame 2-2 (0, 0, 1, 1) to device 1, indicating that the frequencies of TX optical signal 2 and LO optical signal 2 should be adjusted, and also requesting that the frequencies of TX optical signal 1 and LO optical signal 1 be fixed. Device 1, based on frame 2-2 (0, 0, 1, 1), sends frame 1-3 (1, 1, 0, 0) to device 2, indicating that the frequencies of TX optical signal 1 and LO optical signal 1 should be fixed, and also requesting that the frequencies of TX optical signal 2 and LO optical signal 2 be adjusted; that is, device 1 agrees to device 2's request. Then, coherent optical module 2 adjusts the frequencies of LO optical signal 2 and TX optical signal 2 according to the frequency of TX optical signal 1 to converge the frequency offset. Afterwards, device 2 sends frame 2-4 (1, 1, 1, 0) to device 1, indicating that the frequencies of TX optical signal 2 and LO optical signal 2 should be fixed, and also requesting that the frequency of TX optical signal 1 be fixed and the frequency of LO optical signal 1 adjusted. Device 1 sends frame 1-4 (1, 0, 1, 1) to device 2 according to frame 2-4 (1, 1, 1, 0). This is used to indicate fixing the frequency of TX optical signal 1 and adjusting the frequency of LO optical signal 1, and also to request fixing the frequencies of TX optical signal 2 and LO optical signal 2. In other words, device 1 agrees to device 2's request. Subsequently, coherent optical module 1 adjusts the frequency of LO optical signal 1 according to the frequency of TX optical signal 2 to converge the frequency offset.

[0178] Figure 16 This is a schematic diagram of application scenario 3 in the embodiments of this application. For example... Figure 16 As shown, both coherent optical module 1 and coherent optical module 2 use a shared LO light source, corresponding to the application scenario 3 mentioned above. Figure 17 This is a schematic diagram illustrating an implementation method based on application scenario 3 in this application. Wherein, Figure 17The illustrated implementation uses the example where the light source of coherent optical module 1 includes a wavelength locking device, while the light source of coherent optical module 2 does not. That is, coherent optical module 1 is considered the master, and coherent optical module 2 is considered the slave. However, other possible methods can also be used to determine which of the two modules is the master and which is the slave; please refer to the relevant descriptions above for details, which will not be illustrated here. Figure 17 As shown, the implementation method based on application scenario 3 includes the following steps.

[0179] During the capability notification phase, the frames transmitted between device 1 and device 2 include at least two bits. Taking at least two bits used to indicate the local light source type and whether the local light source includes a wavelength locking device as an example, the information corresponding to the different values ​​of these two bits can be found in Table 1. Device 1 sends frame 1-1 (0, 0) to device 2, indicating that device 1's local coherent optical module 1 uses a shared LO light source and that the light source includes a wavelength locking device. Device 2 sends frame 2-1 (0, 1) to device 1, indicating that device 2's local coherent optical module 2 uses a shared LO light source and that the light source does not include a wavelength locking device.

[0180] During the negotiation phase, the frames transmitted between device 1 and device 2 include at least four bits. The meanings of these four bits are: whether the local TX optical signal is adjusted, whether the local LO optical signal is adjusted, requesting adjustment of the peer's TX optical signal, and requesting adjustment of the peer's LO optical signal. The information corresponding to the different values ​​of these four bits can be found in Table 2. Device 1 sends frame 1-2 (0, 0, 1, 1) to device 2, indicating adjustment of the frequencies of TX optical signal 1 and LO optical signal 1, and also requesting a fixation of the frequencies of TX optical signal 2 and LO optical signal 2. Device 2, based on frame 1-2 (0, 0, 1, 1), sends frame 2-3 (1, 1, 0, 0) to device 1, indicating a fixation of the frequencies of TX optical signal 2 and LO optical signal 2, and also requesting adjustment of the frequencies of TX optical signal 1 and LO optical signal 1. In other words, device 2 agrees to device 1's request. Correspondingly, device 2 sends frame 2-2 (1, 1, 0, 0) to device 1 to indicate that the frequencies of TX optical signal 2 and LO optical signal 2 are fixed, and also to request adjustment of the frequencies of TX optical signal 1 and LO optical signal 1. Device 1, based on frame 2-2 (1, 1, 0, 0), sends frame 1-3 (0, 0, 1, 1) to device 2 to indicate that the frequencies of TX optical signal 1 and LO optical signal 1 are being adjusted, and also to request that the frequencies of TX optical signal 2 and LO optical signal 2 be fixed; that is, device 1 agrees to device 2's request. Then, coherent optical module 1 adjusts the frequencies of LO optical signal 1 and TX optical signal 1 according to the frequency of TX optical signal 2 to converge the frequency offset. Afterwards, device 1 sends frame 1-4 (1, 1, 0, 0) to device 2 to indicate that the frequencies of TX optical signal 1 and LO optical signal 1 are fixed, and also to request adjustment of the frequencies of TX optical signal 2 and LO optical signal 2. Device 2 sends frame 2-4 (0, 0, 1, 1) to device 1 based on frame 1-4 (1, 1, 0, 0). This indicates an adjustment to the frequency of TX optical signal 2 and the frequency of LO optical signal 2, and also requests a fixation of the frequency of TX optical signal 1 and the frequency of LO optical signal 1. In other words, device 2 agrees to device 1's request. Subsequently, coherent optical module 2 adjusts the frequency of LO optical signal 2 and the frequency of TX optical signal 2 according to the frequency of TX optical signal 1 to converge the frequency offset.

[0181] Figure 18 This is a schematic diagram of the structure of a communication device in an embodiment of this application. Figure 18As shown, the communication device includes a transmitting unit 101 and a receiving unit 102. The communication device can be either device 1 or device 2 as described in the above embodiments. In one possible implementation, the communication device performs the operations of device 1 in the above embodiments; specifically, the transmitting unit 101 performs the operation of transmitting frames to device 2, and the receiving unit 102 performs the operation of receiving frames from device 2. In another possible implementation, the communication device performs the operations of device 2 in the above embodiments; specifically, the transmitting unit 101 performs the operation of transmitting frames to device 1, and the receiving unit 102 performs the operation of receiving frames from device 1.

[0182] Figure 19 This is a schematic diagram of another structure of the communication device in an embodiment of this application. For example... Figure 19 As shown, the communication device includes a control circuit 201 and an interface circuit 202. It should be understood that the interface circuit 202 can be a transceiver or an input / output interface. The interface circuit is used to receive signals from other devices outside the communication device and transmit them to the control circuit 201, or to send signals from the control circuit 201 to other devices outside the communication device. In one possible implementation, the communication device is used to perform the operations of device 1 in the above embodiments; specifically, the interface circuit 202 is used to perform the operation of device 1 transmitting and receiving frames, and the control circuit 201 is used to perform other operations besides transmitting and receiving frames. In another possible implementation, the communication device is used to perform the operations of device 2 in the above embodiments; specifically, the interface circuit 202 is used to perform the operation of device 2 transmitting and receiving frames, and the control circuit 201 is used to perform other operations besides transmitting and receiving frames. Optionally, the communication device may also include a memory 203, wherein the memory 203 is used to store program instructions and data.

[0183] This application also provides a chip. This chip integrates circuitry for implementing the functions of the control circuit 201 described above, and one or more interfaces. As an example, the chip integrates a memory. As another example, when the chip does not integrate a memory, it can be connected to an external memory via the interface. This chip can perform the method steps of any one or more of the foregoing embodiments. Alternatively, the chip can implement the actions performed by the data processing device in the foregoing embodiments based on program code stored in the memory.

[0184] As an example, the chip in the embodiments of this application can be a CPU, or other general-purpose processors, DSPs, ASICs, field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor, any conventional processor, or a processing circuit that implements a specific function.

[0185] This application also provides a computer-readable storage medium including a program or instructions that, when run on a computer, cause the method performed as described in the above method embodiments to be implemented.

[0186] It should be understood that the control circuit mentioned in the embodiments of this application can be implemented in hardware or software. When implemented in hardware, the control circuit can be a logic circuit, integrated circuit, etc. When implemented in software, the control circuit can be a general-purpose processor that reads software code stored in memory. The memory can exist independently and be connected to the control circuit, or the memory can be integrated with the control circuit.

[0187] As an example, the control circuit in the embodiments of this application can be a CPU, or other general-purpose processors, DSPs, ASICs, FPGAs, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor can be a microprocessor, any conventional processor, or a processing circuit that implements a specific function.

[0188] In embodiments of this application, the memory may be random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, portable hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium may also be a component of the processor. The processor and storage medium may reside in an ASIC. Additionally, the ASIC may reside in a network device or a terminal device. Alternatively, the processor and storage medium may exist as discrete components in the network device or terminal device.

[0189] In the above embodiments, it can be implemented entirely or partially by software, hardware, firmware, or any combination thereof.

[0190] When implemented in hardware, the data processing method provided in this application embodiment may be implemented without reading software code or instructions. For example, it may be implemented by CPU, DSP, ASIC, FPGA, other programmable logic devices, transistor logic devices, hardware components, or any combination thereof.

[0191] When implemented using software, it can be implemented entirely or partially in the form of a computer program product. A computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, all or part of the processes or functions of the embodiments of this application are performed. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a terminal device, or other programmable device. The computer program or instructions can be stored in or transmitted through a computer-readable storage medium. The computer-readable storage medium can be any available medium that a computer can access, or a data storage device such as a server integrating one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a Digital Versatile Disc (DVD); or it can be a semiconductor medium, such as a solid-state disk (SSD).

[0192] Finally, it should be noted that the above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An information transmission method based on a coherent optical module, characterized in that, include: The first device sends a first frame to the second device. The first frame is used to indicate whether the local oscillator (LO) optical signal in the first coherent optical module and the optical signal to be transmitted are from the same source. The first device is the first coherent optical module, or the first device is connected to the first coherent optical module. The first device receives a second frame sent by the second device. The second frame is used to indicate whether the LO optical signal in the second coherent optical module and the optical signal to be transmitted are from the same source. The second device is the second coherent optical module, or the second device is connected to the second coherent optical module.

2. The method according to claim 1, characterized in that, In a coherent optical module using the first type of light source, the LO optical signal and the optical signal to be transmitted are from different sources; in a coherent optical module using the second type of light source, the LO optical signal and the optical signal to be transmitted are from the same source.

3. The method according to claim 1 or 2, characterized in that, The first frame is also used to indicate whether there is a wavelength locking device in the light source of the first coherent optical module, and the second frame is also used to indicate whether there is the wavelength locking device in the light source of the second coherent optical module.

4. The method according to any one of claims 1 to 3, characterized in that, The first frame is also used to indicate the accuracy of the emission frequency of the light source in the first coherent optical module, and the second frame is also used to indicate the accuracy of the emission frequency of the light source in the second coherent optical module.

5. The method according to any one of claims 1 to 4, characterized in that, The method further includes: The first device sends a third frame to the second device. The third frame is used to request the second coherent optical module to fix the frequency of the second LO optical signal or adjust the frequency of the second LO optical signal. The third frame is also used to request the second coherent optical module to fix the frequency of the second optical signal or adjust the frequency of the second optical signal. The second LO optical signal and the second optical signal are generated by the second coherent optical module, and the second optical signal is used to send to the first coherent optical module.

6. The method according to claim 5, characterized in that, After the first device sends the third frame to the second device, the method further includes: The first device receives a fourth frame sent by the second device based on the third frame, the fourth frame being used to indicate whether the request of the third frame is agreed to.

7. The method according to claim 6, characterized in that, The fourth frame is used to instruct the second coherent optical module to fix the frequency of the second LO optical signal or adjust the frequency of the second LO optical signal. The fourth frame is also used to instruct the second coherent optical module to fix the frequency of the second optical signal or adjust the frequency of the second optical signal.

8. The method according to any one of claims 5 to 7, characterized in that, The third frame is also used to instruct the first coherent optical module to fix the frequency of the first LO optical signal or adjust the frequency of the first LO optical signal. The third frame is also used to instruct the first coherent optical module to fix the frequency of the first optical signal or adjust the frequency of the first optical signal. The first LO optical signal and the first optical signal are generated by the first coherent optical module, and the first optical signal is used to send to the second coherent optical module.

9. The method according to any one of claims 5 to 8, characterized in that, The third frame is also used to request the second coherent optical module to transmit signals using a first signal mode, the first signal mode including at least one of a first signal modulation format and a first signal baud rate.

10. The method according to claim 9, characterized in that, After the first device sends a third frame to the second device, the method further includes: The first device sends a fifth frame to the second device. The fifth frame is used to request the second coherent optical module to fix or adjust the frequency of the second LO optical signal. The fifth frame is also used to request the second coherent optical module to fix or adjust the frequency of the second optical signal. The fifth frame is also used to request the second coherent optical module to transmit the signal using a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate.

11. The method according to claim 10, characterized in that, The second signal modulation format is higher than the first signal modulation format, and the second signal baud rate is greater than the first signal baud rate.

12. The method according to any one of claims 5 to 11, characterized in that, If the third frame is used to request the second coherent optical module to adjust the frequency of the second LO optical signal, and the second device agrees to the request of the third frame, the absolute value of the difference between the frequency of the first optical signal sent by the first coherent optical module and the frequency of the adjusted second LO optical signal is less than the absolute value of the difference between the frequency of the first optical signal sent by the first coherent optical module and the frequency of the second LO optical signal before adjustment.

13. The method according to any one of claims 5 to 12, characterized in that, In the first coherent optical module, the first LO optical signal and the first optical signal are from different sources; in the second coherent optical module, the second LO optical signal and the second optical signal are from the same source; the third frame is used to request the second coherent optical module to adjust the frequency of the second LO optical signal and the frequency of the second optical signal. After the second coherent optical module adjusts the frequency of the second LO optical signal and the frequency of the second optical signal according to the frequency of the first optical signal, the method further includes: The first device receives a sixth frame sent by the second device. The sixth frame is used to request the first coherent optical module to adjust the frequency of the first LO optical signal and fix the frequency of the first optical signal.

14. The method according to claim 13, characterized in that, The third frame is also used to request the second coherent optical module to transmit signals using a first signal mode, wherein the first signal mode includes at least one of a first signal modulation format and a first signal baud rate; After the first coherent optical module adjusts the frequency of the first LO optical signal according to the frequency of the second optical signal, the method further includes: The first device sends a fifth frame to the second device. The fifth frame is used to request the second coherent optical module to adjust the frequency of the second LO optical signal and the frequency of the second optical signal. The fifth frame is also used to request the second coherent optical module to transmit the signal using a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate.

15. The method according to any one of claims 5 to 12, characterized in that, In the first coherent optical module, the first LO optical signal and the first optical signal are from different sources; in the second coherent optical module, the second LO optical signal and the second optical signal are from different sources. The third frame is used to request the second coherent optical module to adjust the frequency of the second LO optical signal and fix the frequency of the second optical signal. The method further includes: The first device receives a seventh frame sent by the second device. The seventh frame is used to request the first coherent optical module to adjust the frequency of the first LO optical signal and fix the frequency of the first optical signal.

16. The method according to claim 15, characterized in that, The third frame is also used to request the second coherent optical module to transmit signals using a first signal mode, wherein the first signal mode includes at least one of a first signal modulation format and a first signal baud rate; After the first coherent optical module adjusts the frequency of the first LO optical signal according to the frequency of the second optical signal, the method further includes: The first device sends a fifth frame to the second device. The fifth frame is used to request the second coherent optical module to adjust the frequency of the second LO optical signal and fix the frequency of the second optical signal. The fifth frame is also used to request the second coherent optical module to transmit the signal using a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate.

17. The method according to any one of claims 1 to 12, characterized in that, In the first coherent optical module, the first LO optical signal and the first optical signal are from the same source; in the second coherent optical module, the second LO optical signal and the second optical signal are from the same source; the method further includes: The first device negotiates with the second device to determine that the first coherent optical module first adjusts the frequency of the first LO optical signal and the frequency of the first optical signal, and then the second coherent optical module adjusts the frequency of the second LO optical signal and the frequency of the second optical signal.

18. The method according to any one of claims 5 to 12, characterized in that, In the first coherent optical module, the first LO optical signal and the first optical signal are from the same source; in the second coherent optical module, the second LO optical signal and the second optical signal are from the same source. The first coherent optical module has a wavelength locking device in its light source, the second coherent optical module does not have a wavelength locking device in its light source, and / or the accuracy of the emission frequency of the light source in the first coherent optical module is greater than the accuracy of the emission frequency of the light source in the second coherent optical module. The third frame is used to request the second coherent optical module to fix the frequency of the second LO optical signal and the frequency of the second optical signal. The method further includes: The first device receives an eighth frame sent by the second device, the eighth frame being used to request the first coherent optical module to adjust the frequency of the first LO optical signal and the frequency of the first optical signal; After the first coherent optical module adjusts the frequency of the first LO optical signal and the frequency of the first optical signal according to the frequency of the second optical signal, the method further includes: The first device sends a ninth frame to the second device, the ninth frame being used to request the second coherent optical module to adjust the frequency of the second LO optical signal and the frequency of the second optical signal.

19. The method according to claim 18, characterized in that, The third frame is also used to request the second coherent optical module to transmit signals using a first signal mode, wherein the first signal mode includes at least one of a first signal modulation format and a first signal baud rate; After the second coherent optical module adjusts the frequency of the second LO optical signal and the frequency of the second optical signal according to the frequency of the first optical signal, the method further includes: The first device receives a tenth frame sent by the second device. The tenth frame is used to request the first coherent optical module to adjust the frequency of the first LO optical signal and the frequency of the first optical signal. The tenth frame is also used to request the first coherent optical module to transmit the signal using a second signal mode. The second signal mode includes at least one of a second signal modulation format and a second signal baud rate.

20. A chip, characterized in that, The chip includes a processor for performing the method as described in any one of claims 1 to 19.

21. A communication device, characterized in that, The communication device includes a control circuit and an interface circuit, the interface circuit being used to transmit and receive signals, and the control circuit being used to perform the method as described in any one of claims 1 to 19.

22. A communication system, characterized in that, The communication system includes a first device and a second device, wherein the first device is used to perform the method as described in any one of claims 1 to 19.

23. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed by a computer, cause the method as described in any one of claims 1 to 19 to be implemented.

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