Method and apparatus for implementing flexible rate

Abstract

The present invention discloses a method for implementing flexible rate: an optical receiving component in the client receives an optical signal from the host with an optical power value of P1, and monitors the received optical power P1 to calculate the received optical power value P r ; wherein, after the host and the client are correctly deployed, a normal communication mechanism is established through the NRZ code pattern; compensating for the optical power value P r to calculate the current received power P test of the client, and calculating the power difference ΔP between the current received power P test of the client and the optical receiving sensitivity value P0 of the optical receiving component; comparing the power difference ΔP with a previously predetermined threshold to determine which modulation format the downstream channel can be adjusted to, and using the determined modulation format as the first uplink frame to be sent from the client to the host, so that after the host receives the first uplink frame, it adjusts the downstream channel modulation format according to the determined modulation format to achieve flexible code pattern change. The present invention also provides a corresponding device for implementing flexible rate.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technologies, passive optical networks or point-to-point optical Ethernet. Specifically, it relates to a method and apparatus for implementing flexible rates. Background Art

[0002] The flexibility and intelligence of networks are prominent features of the new round of scientific and technological revolution and also the development trend of the new generation of information technologies. At present, high-speed large bandwidth remains the main theme of the development of optical networks, and the demand for flexible and efficient services will be increasingly large. In the field of optical communication, the flex-rate passive optical access network (flex-rate PON) technology is a new technology that combines the passive optical network (PON) with the concept of network flexibility and is also a hot topic discussed in the industry.

[0003] As is well known, a passive optical network (PON: Passive Optical Network) system consists of three parts, namely the optical line terminal (OLT: Optical Line Termination) of the central office equipment, the optical distribution network (ODN: Optical Distribution Network), and the optical network unit (ONU: Optical Network Unit) of the remote device. After the three are deployed on a large scale, data can be normally transmitted between the OLT and ONU devices. According to standards G984.1, G987.1, and G9804.1, for mainstream PON technologies such as GPON, XG(S)-PON, and 50G-PON, their upstream and downstream transmission rates are fixed. For example, the upstream and downstream rates of XGS-PON are both 9.953 Gbps; the upstream rate of 50G-PON is 12.5 or 25 Gbps, and the downstream rate is 50 Gbps, etc., as Figure 1 shown, both a and b are constants. Moreover, different generations of PON technologies evolve along the TDM method and the fixed-line NRZ modulation format route. If evolved in this way, smoothly upgrading from 50G-PON to a higher-speed PON such as 100G-PON and 200G-PON requires optoelectronic devices with higher bandwidth, and it is impossible to complete the smooth evolution ability based on the current bandwidth limitations of optoelectronic devices. In addition, if the optical power margin provided by the devices in the existing network is sufficient, it is also impossible to flexibly change different modulation methods or flexibly increase the line throughput to provide higher bandwidth for customers. Therefore, based on the existing optoelectronic devices, how to achieve a larger throughput to provide higher bandwidth for customers is a problem that PON technology needs to solve. Summary of the Invention

[0004] In view of the above deficiencies or improvement requirements of the prior art, the present invention proposes a method for implementing flexible rates, which adaptively and flexibly modulates according to the link conditions, realizes the ability to increase bandwidth and throughput based on existing optoelectronic devices, improves the flexibility of the network, and gives full play to the value of the deployed optical network infrastructure.

[0005] To achieve the above object, according to one aspect of the present invention, there is provided a method for implementing flexible rates, the method comprising:

[0006] The optical receiving component in the client receives the optical signal from the host end with an optical power value of P1, monitors the received optical power P1, and calculates the received optical power value P r ; wherein, after the host end and the client are correctly deployed, a normal communication mechanism is established through the NRZ code pattern;

[0007] Compensate for the optical power value P r to calculate the current received power P test of the client, and calculate the power difference ΔP between the current received power P test of the client and the optical receiving sensitivity value P0 of the optical receiving component;

[0008] Compare the power difference ΔP with a previously predetermined threshold to determine which modulation format the downstream channel can be adjusted to, and use the determined modulation format as the first upstream frame to be sent from the client to the host end. After the host end receives the first upstream frame, adjust the downstream channel modulation format according to the determined modulation format to achieve flexible code pattern changes.

[0009] In an embodiment of the present invention, the compensation for the input P r specifically includes: compensating the input P test according to the formula P r = P r + offset to calculate the current received power P test of the client, where offset is used to compensate for the deviation between the calculated value and the actual value.

[0010] In an embodiment of the present invention, the predetermined threshold is equal to the deviation value between the NRZ code pattern and code patterns such as PAM4 and PAM8 plus the theoretical optical power difference.

[0011] In an embodiment of the present invention, the comparison of ΔP with the previously predetermined threshold to determine which modulation format the downstream channel can be adjusted to specifically includes:

[0012] If 0 < ΔP ≤ the first threshold, negotiate to transmit the signal in the NRZ code pattern;

[0013] If the first threshold < ΔP ≤ the second threshold, adjust to PAM4 transmission through negotiation;

[0014] If the second threshold < ΔP, adjust to PAM8 transmission through negotiation;

[0015] And so on...;

[0016] Wherein the first threshold and the second threshold are preset values.

[0017] In one embodiment of the present invention, the first threshold is 6.77 and the second threshold is 10.45.

[0018] In one embodiment of the present invention, the calculation of P test And the power difference ΔP between the optical receiving sensitivity value P0 of the optical receiving component specifically includes:

[0019] Calculate the power difference ΔP according to the formula ΔP = P test - P0, where P0 is the sensitivity value of the optical receiving component at NRZ coding and a preset bit error rate level.

[0020] In one embodiment of the present invention, the preset bit error rate level is: 1×10 below the signal rate of 25G -3 Or 1×10 above the signal rate of 25G -2 .

[0021] According to another aspect of the present invention, there is also provided a device for realizing flexible rate, including: an optical receiving component, a power monitoring module, and a calculation and processing unit, wherein:

[0022] The optical receiving component and the power monitoring module are used to receive the optical signal and monitor the optical power;

[0023] The calculation and processing unit is used to compensate and calculate the received power, and determine the modulation format according to the difference to realize flexible change of the code pattern.

[0024] In one embodiment of the present invention, the optical receiving component and the power monitoring module are composed of an optical receiving component and a power monitoring module, wherein:

[0025] The optical receiving component is used to receive the optical signal from the host side, complete the conversion of the optical and electrical signals, and output a normal data signal to the service unit;

[0026] The power monitoring module is used to monitor the optical receiving power of the optical signal received from the host side and output the detected received optical power.

[0027] In one embodiment of the present invention, the calculation and processing unit is composed of a calculation module, a comparison module, and a discrimination module, wherein:

[0028] The calculation module is used to complete the sampling, fitting and calculation of the received optical power P r to obtain the currently received optical power P test , and send this value to the comparison module;

[0029] The comparison module is used to subtract P test from the optical reception sensitivity P0 of the optical receiving component, give the difference ΔP between the two, and output the difference to the discrimination module;

[0030] The discrimination module is used to compare ΔP with a predetermined threshold, determine whether this value meets the requirements of flexible code pattern change, and output the determined modulation format, and send it to the host side through the first frame of data so that the host side can adjust the downlink channel modulation format according to the determined modulation format to achieve flexible code pattern change.

[0031] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the following beneficial effects are obtained:

[0032] (1) The device can, according to the specific situation in reality, make the most of the power margin at the receiver end, flexibly adjust different modulation formats, such as PAM4, PAM8, etc., to achieve higher uplink and downlink transmission rates, improve the transmission bandwidth of the device, and thus provide higher bandwidth for customers and bring a better experience;

[0033] (2) If the specific conditions cannot meet the requirement for the device to transmit in modulation methods with a larger number of levels such as PAM4 and PAM8, the network can still transmit in the NRZ modulation format, and it will not cause the device to be unable to operate;

[0034] (3) If the specific situation in reality changes, the device can flexibly adjust the modulation method by itself without human interference, which not only improves the rate, but also is very convenient and reduces the relevant costs. Brief Description of the Drawings

[0035] Figure 1 is the communication architecture of the passive optical network in the prior art;

[0036] Figure 2 is the eye diagram of different modulation formats; where Figure 2(a) is the NRZ eye diagram, Figure 2(b) is the PAM4 eye diagram, and Figure 2(c) is the PAM8 eye diagram;

[0037] Figure 3 is the structural schematic diagram of the device for realizing flexible rate in the embodiment of the present invention;

[0038] Figure 4 is the PON structure in the embodiment of the present invention. Detailed Embodiment

[0039] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] As Figure 1 shown, whether it is the technically mature GPON, XG(S)-PON or the ongoing 50G-PON, if the relevant hardware has been deployed, the uplink and downlink transmission rates are fixed and immutable, and the specific values have been determined in the relevant standards. Suppose when the device is running in the system, there is still a relatively high power margin at the receiving end, and this margin is sufficient to achieve a higher transmission rate through a higher-order modulation format. However, due to the lack of relevant modules in the system, the foregoing effects cannot be achieved, and thus a better user experience cannot be provided for customers.

[0041] Therefore, in this case, the following two problems must be solved:

[0042] (1) It is necessary to calculate the theoretical value of the power difference between the multi-amplitude modulation format and the NRZ modulation, and it is necessary to determine a reasonable actual power difference according to the actual situation, so that the device can adjust the modulation format according to the actual situation.

[0043] (2) Add relevant modules to the optical access system to implement the functions of the above-mentioned flex-rate PON, that is, the modulation format can be flexibly adjusted according to the current optical power margin of the device.

[0044] First, the calculation of the theoretical power difference: NRZ (PAM2 1 ), PAM4 (PAM2 2 ), PAM8 (PAM2 3 )(can be further extended to PAM16) modulation code patterns, etc. all belong to pulse amplitude modulation code patterns, and the output eye diagrams are shown in Figure 2. According to theoretical analysis, if a modulation format with more levels is applied for uplink and downlink, the difference between the optical power P1 (@BER = 2×10 -4 , PAMn) received by the optical receiver and the receiver sensitivity P0 (@BER = 1E-3, NRZ, where 1E-3 is 1×10 -3 ) will increase. Since the energy carried by each level decreases as the number of levels increases. For example: NRZ modulation is two-level. Assuming that the total amplitude of the levels is 1V, that is, in the case of NRZ, the eye diagram has only a single eye, and the energy of this single eye is 1, which is converted into a logarithm of -10lg(2 1 -1) = 0dB. PAM4 (2 2= 4) When the modulation is four - level, assuming the total level amplitude is 1V, then the amplitude of each level is 1 / 3V. That is, for PAM4, there are three eye diagrams, and the energy of each eye diagram accounts for 1 / 3. Converted to logarithm, it is 10lg(1 / 3)= - 4.77dB; if PAM8(2 3 = 8) When the modulation is eight - level, the total level amplitude is 1V, then the amplitude of each level is 1 / 7V. That is, for PAM8, there are 7 eye diagrams, and the energy of each eye diagram accounts for 1 / 7. Converted to logarithm, it is 10lg(1 / 7)= - 8.45dB. And so on, the more the number of levels, the more the energy carried by each level decreases. After specific calculations according to the above formula (PAM2 n Power attenuation - 10lg(2 n - 1), its theoretical difference from NRZ is: 10lg(2 1 - 1)-(- 10lg(2 n - 1)) = 10lg(2 n - 1)), and the theoretical value of the power difference between the multi - amplitude modulation format and NRZ modulation can be obtained. In practical applications, due to the influence of the physical optical link and optical devices on the multi - amplitude modulation pattern, the actual value has a greater power attenuation than the theoretical value and has a positive deviation. Calculated according to the power deviation of + 2dB, its power difference is shown in Table 1.

[0045] Table 1

[0046]

[0047] The reference value is the NRZ pattern

[0048] Therefore, the present invention uses this difference as a reference value to determine which modulation method can be adopted for the uplink and downlink channels, and then adjusts the modulation format according to the actual situation to realize a flex - rate optical access system. It should be noted that since there are still other factors causing power loss in the actual application process, the actual judgment threshold is larger than the calculated theoretical value.

[0049] Then, a module with a flexible modulation pattern is added to the optical access system. The added module mainly consists of an optical receiving component, a power monitoring module, and a calculation and processing unit, as Figure 3 shown.

[0050] The optical receiving component and power monitoring module consists of an optical receiving component and a power monitoring module. The optical receiving component mainly receives the optical signal from the host side, completes the conversion of optical and electrical signals, and outputs the normal data signal Data0 to the service unit. At the same time, the power monitoring module monitors the optical receiving power of the optical signal received from the host side and outputs the detected received optical power P r .

[0051] The calculation and processing unit mainly consists of a calculation module, a comparison module, and a discrimination module. The calculation module mainly completes the sampling, fitting, and calculation of the received optical power P r and calculates the currently received optical power P test , and sends this value to the comparison module; the comparison module mainly subtracts P test from the optical reception sensitivity P0 of the optical receiving component, gives the difference ΔP between the two, and outputs the difference to the discrimination module, where P0 refers to the optical power value received by the optical receiving component under the conditions of NRZ code pattern and a certain bit error rate BER (for example, 1×10 -3 below 25G rate or 1×10 -2 above 25G rate); the discrimination module mainly compares ΔP with a predetermined threshold, determines whether this value meets the requirements of flexible code pattern change, and outputs the determined modulation format result, and sends it to the host side through the first frame of data so that the host side adjusts the downlink channel modulation format according to the determined modulation format to achieve flexible code pattern change, where the predetermined threshold is equal to the deviation value between the NRZ code pattern and code patterns such as PAM4 and PAM8 + the theoretical optical power difference, as shown in Table 1.

[0052] To implement the above technical solution, the present invention provides a method for implementing flexible rate, and the method includes:

[0053] The optical receiving component in the client receives the optical signal from the host side, and its optical power value is P1. Monitor the received optical power P1 and calculate the received optical power value P r ; among them, after the host side and the client are correctly deployed, a normal communication mechanism is established through the NRZ code pattern;

[0054] Compensate for the optical power value P r and calculate the current received power P test of the client, and calculate the power difference ΔP between the current received power P test of the client and the optical reception sensitivity value P0 of the optical receiving component;

[0055] Compare the power difference ΔP with the previously predetermined threshold to determine which modulation format the downlink channel can be adjusted to, and use the determined modulation format as the first uplink frame to be sent by the client to the host side, so that after the host side receives the first uplink frame, it adjusts the downlink channel modulation format according to the determined modulation format to achieve flexible code pattern change.

[0056] Specifically, the specific implementation method of flexible rate is as follows:

[0057] (1) After the host side and the client are correctly deployed, first establish a normal communication mechanism through the NRZ code pattern;

[0058] (2) Then, the optical receiving component in the client receives the optical signal from the host with an optical power value of P1. After photoelectric conversion, it outputs a normal data signal Data0, and inputs this signal into the service unit for normal service transmission. The power monitoring module monitors the received optical power P1 and calculates the received optical power value P r according to the existing technology in the industry currently, and outputs this value to the calculation and processing module;

[0059] (3) The calculation module compensates the input P test = P r + offset to a certain extent, and calculates the current received power P r of the client, where offset is used to compensate for the deviation between the calculated value and the actual value; test

[0060] (4) The comparison module compares the optical receiving sensitivity value P0 of the optical receiving component and P test in step (3) according to the formula ΔP = P test - P0 to obtain the power difference ΔP, and outputs this difference to the discrimination module. Where P0 is the sensitivity value of the optical receiving component at NRZ coding and a certain bit error rate level. This bit error rate level is generally 1×10 -3 or 1×10 -2 below the signal rate of 25G or above the signal rate of 25G;

[0061] (5) The discrimination module compares ΔP with the previously predetermined theoretical threshold to determine which modulation format the downstream channel can be adjusted to. The comparison is as follows:

[0062] · If 0 < ΔP ≤ 4.77, then negotiate to transmit the signal in the NRZ code pattern;

[0063] · If 4.77 < ΔP ≤ 8.45, then negotiate to adjust to result = PAM4 transmission;

[0064] ● If 8.45 < ΔP ≤ 11.76, then negotiate to adjust to result = PAM8 transmission;

[0065] ● If 10lg(2 n - 1) < ΔP ≤ 10lg(2 n+1 - 1), then negotiate to adjust to result = PAM2 n transmission. And so on...

[0066] If compared according to the threshold of deviation + 2dB to determine which modulation format the downstream channel can be adjusted to, the comparison is as follows:

[0067] ​● If 0 < ΔP ≤ 6.77, then signal transmission is carried out through negotiation with result = NRZ code pattern;

[0068] · If 6.77 < ΔP ≤ 10.45, then adjust to result = PAM4 transmission through negotiation;

[0069] · If 10.45 < ΔP ≤ 13.76, then adjust to result = PAM8 transmission through negotiation;

[0070] · If 10lg(2 n - 1)+2 < ΔP ≤ 10lg(2 n+1 - 1)+2, then adjust to result = PAM2 n transmission through negotiation. And so on............

[0071] And take the comparison result result as the first uplink frame and send it from the client to the host side. Wherein the threshold is equal to the deviation value between the NRZ code pattern and code patterns such as PAM4 and PAM8 + the theoretical optical power difference value. According to the actual situation, the threshold can be defined by itself.

[0072] Here, the embodiments of the present invention give a method for theoretical benchmark comparison. Customers can increase the insertion loss based on this theoretical value according to the actual link situation.

[0073] (6) The host side receives the first uplink frame and adjusts the downlink channel modulation format according to the judgment result to achieve flexible code pattern change.

[0074] The following describes the method of the present invention in conjunction with a specific embodiment:

[0075] Take the downlink channel of an optical system with a line rate of 10 Gb / s as an example to illustrate the implementation scheme of the present invention. As Figure 4 shown, the PON system consists of a host side (OLT) and a client side (ONU), and the ODN link loss OPL is 29 dB. If the optical receiving component uses an avalanche photodiode (APD) with an optical receiving rate of 10 Gb / s, its own optical receiving sensitivity is -30 dBm, and this -30 dBm is the value under the condition that the modulation code pattern is NRZ and the line bit error rate is 1×10 -3 of.

[0076] The steps for the system to achieve flexible code pattern change are as follows:

[0077] Step 1: After the host side and the client side are correctly deployed, the PON network first completes normal communication between the two ends through the NRZ code.

[0078] Step 2: Subsequently, the host end (point S) transmits an optical power of +8 dBm. After passing through an ODN link loss of 29 dB, the optical power P1 at the client-side optical interface (point R) is -21 dBm. After photoelectric conversion within the client, a normal data signal Data0 is output and input into the service unit for normal service transmission. The power monitoring module monitors the received optical power P1 and calculates the received optical power value P according to the existing technologies in the industry currently. r and inputs this value into the calculation module.

[0079] Step 3: To reduce calculation deviation and power losses of other devices, the calculation module calculates the client received power P r according to the value of the input signal P test = P r + offset. offset is the deviation value between the calculated value and the actual value. In the example cited in this patent, the calculation result of P test should be approximately -21 dBm; test

[0080] Step 4: After the calculation module obtains P test in Step 2, it inputs this result into the comparison module. The comparison module calculates the power difference ΔP according to the formula ΔP = P test - P0, and obtains ΔP = 9 dB through calculation; where P0 is the sensitivity value of the optical receiver at the NRZ coding and bit error rate of 1×10 -3 level. In this example, P0 is -30 dBm and P test is -21 dBm;

[0081] ​Step 5: After the comparison module calculates that ΔP is 9 dB in Step 3, it inputs this result to the discrimination module. The function of the discrimination module is to determine what modulation format the downstream channel can be adjusted to according to the ΔP value and a predetermined threshold, and send this judgment result as the first upstream frame from the client to the host. This predetermined threshold is determined by the customer himself and is a theoretical value or a value after adding a deviation. In this example, the value of ΔP received by the discrimination module is approximately 9 dB. As can be seen from Table 1, theoretically, when the power difference is greater than 4.77 dB, the optical network can operate in the PAM4 modulation format; when the power difference is greater than 8.45 dB, the optical network can operate in the PAM8 modulation format. However, due to power loss in the actual application process, there will be a certain deviation in the link. Considering an increase of 2 dB deviation in the actual physical layer link loss, when the power difference is greater than 6.77 dB, it is ensured that the device can safely switch to PAM4. Therefore, according to the foregoing standard, in this embodiment, ΔP is 9 dB > 6.77 dB, and it can be safely switched to the PAM4 modulation pattern. The client will send the result information of "changing the modulation format of the downstream channel to PAM4" as the first upstream frame to the host.

[0082] Step 6: When the host receives the information of switching to PAM4 from the client in the first upstream frame, the host will change to the PAM4 modulation format in the subsequent communication process. If the system environment or link conditions change later, the client will still tell the host to switch to the modulation format suitable for the current conditions according to the power margin situation to achieve flexible code pattern change.

[0083] The above method is also applicable to flexible switching in optical communication networks such as data centers. The flexible switching method will not be elaborated here.

[0084] Those skilled in the art can easily understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for implementing a flexible rate, characterized in that, The method includes: The optical receiving component within the client receives the optical signal from the host, and its optical power value is P1. The received optical power P1 is monitored and calculated to obtain the received optical power value P r ; where, after the host and the client are correctly deployed, a normal communication mechanism is established through the NRZ code pattern; Compensate for the optical power value P r to calculate the current received power P test of the client, and calculate the power difference ΔP between the current received power P test of the client and the optical receiving sensitivity value P0 of the optical receiving component; Comparing the power difference ΔP with a previously predetermined threshold to determine what modulation format the downstream channel can be adjusted to, and using the determined modulation format as the first upstream frame to be sent from the client to the host. After receiving the first upstream frame, the host adjusts the downstream channel modulation format according to the determined modulation format to achieve flexible code pattern variation.

2. The method for implementing a flexible rate according to claim 1, characterized in that The compensation for the optical power value P r is performed, specifically including: According to the formula P test = P r + offset to perform a certain compensation on the input P r to calculate the current client received power P test , where offset is used to compensate for the deviation between the calculated value and the actual value.

3. The method for implementing a flexible rate as claimed in claim 1 or 2, characterized in that, The predetermined threshold is equal to the deviation value between the NRZ pattern and PAM4, PAM8... PAM2 n + the theoretical optical power difference between each pattern.

4. The implementation method of flexible rate according to claim 3, characterized in that, Comparing the ΔP with a previously predetermined threshold to determine what modulation format the downstream channel can be adjusted to, specifically including: If 0 < ΔP ≤ the first threshold, signal transmission is carried out in the NRZ code pattern through negotiation; If the first threshold < ΔP ≤ the second threshold, adjustment is made to PAM4 transmission through negotiation; If the second threshold < ΔP ≤ the third threshold, adjustment is made to PAM8 transmission through negotiation; If 10lg(2 n -1) < ΔP ≤ 10lg(2 n+1 -1), then adjust it to result = PAM2 n for transmission through negotiation; wherein the first threshold, the second threshold, and the third threshold are preset values.

5. The method for implementing a flexible rate according to claim 4, wherein If the comparison is made according to the threshold of deviation +2dB, the first threshold is 6.77 and the second threshold is 10.

45.

6. The method for implementing a flexible rate according to claim 1 or 2, characterized in that, The calculated P test and the power difference ΔP between the optical reception sensitivity value P0 of the optical reception component, specifically including: According to the formula ΔP = P test - P0, the power difference ΔP is obtained, where P0 is the sensitivity value of the optical receiving component at the NRZ coding and the preset bit error rate level.

7. The method for implementing a flexible rate according to claim 6, wherein The preset error rate level is: below 25G rate of the signal, 1×10 -3 or above 25G rate, 1×10 -2 .

8. An apparatus for implementing a flexible rate, characterized in that It includes: An optical receiving component, a power monitoring module, and a calculation and processing unit, wherein: The optical receiving component and the power monitoring module are used to receive the optical signal from the host end with an optical power value of P1, monitor the received optical power P1, and calculate the received optical power value P r ; The calculation and processing unit is configured to compensate the optical power value P r and calculate the current received power P test of the client, and determine the modulation format according to the difference to achieve flexible code pattern variation; the difference is the power difference ΔP between the current received power P test of the client and the optical reception sensitivity value P0 of the optical reception component.

9. The implementation device with a flexible rate according to claim 8, characterized in that, The optical receiving component and the power monitoring module are composed of an optical receiving component and a power monitoring module, wherein: The optical receiving component is used to receive the optical signal from the host, complete the conversion of optical and electrical signals, and output a normal data signal to the service unit; The power monitoring module is used to monitor the optical receiving power of the optical signal received from the host and calculate the received optical power value Pr.

10. The flexible rate implementation device according to claim 8 or 9, characterized in that, The calculation and processing unit is composed of a calculation module, a comparison module, and a discrimination module, wherein: The calculation module is used to complete the sampling, fitting and calculation of the received optical power value P r to obtain the current client received power P test , and send this value to the comparison module; The comparison module is used to subtract P test from the optical reception sensitivity P0 of the optical reception component, give the difference ΔP between the two, and output the difference to the discrimination module; The discrimination module is used to compare the ΔP with a predetermined threshold, determine whether the value meets the requirements of flexible code pattern variation, and output the determined modulation format, which is sent to the host through the first frame of data so that the host adjusts the downstream channel modulation format according to the determined modulation format to achieve flexible code pattern variation.

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