An 800G PAM4 signal compensation method and device based on channel crosstalk characteristics and a medium

Abstract

This invention discloses an 800G PAM4 signal compensation method, device, and medium based on channel crosstalk characteristics, relating to the field of four-level signal compensation technology. The method includes: acquiring multi-channel PAM4 received sampling data within a compensation period to form a PAM4 transition response sampling record; calculating the transition residual using the same-level retention residual as a reference, and extracting the channel crosstalk response based on the forward and reverse transition residuals to form a channel crosstalk response record; generating a sampled value compensation amount based on the channel crosstalk response record, and forming a recentered PAM4 decision boundary or a PAM4 decision boundary retention value to obtain a PAM4 signal compensation parameter record; forming a compensated PAM4 decision record based on the PAM4 signal compensation parameter record, and incorporating the compensated residual into the next compensation period. This invention achieves separate extraction of the channel crosstalk response and recentering adjustment of the PAM4 decision boundary according to the sampled value compensation amount.

Description

Technical Field

[0001] This invention relates to the field of four-level signal compensation technology, and in particular to an 800GPAM4 signal compensation method, device and medium based on channel crosstalk characteristics. Background Technology

[0002] As data center interconnects, switching equipment interconnects, and high-speed optoelectronic transceiver links evolve towards higher throughput, PAM4 modulation, capable of carrying multiple bits of information within a unit symbol period, is widely used in high-speed serial and multi-channel parallel transmission scenarios. For multi-channel PAM4 receiver links with total rates reaching 800G, the receiving side typically combines clock recovery, front-end equalization, sampling phase control, and PAM4 decision processing to handle the received waveform, maintaining symbol recovery consistency based on the PAM4 level center value, sampling deviation, and decision boundaries.

[0003] However, existing methods still have two limitations: First, conventional compensation often describes the influence of adjacent channels by using overall sampling deviation or fixed correction parameters, and rarely distinguishes between the residual reference of adjacent interfering channels under the same level maintenance state and the directional residual of PAM4 level under the jumping state, making it difficult to extract the channel crosstalk response separately; Second, the PAM4 decision boundary is usually formed based on the original level center or uniform offset, making it difficult to recenter and adjust the compensation amount of the sampled value under the jumping direction according to different PAM4 levels. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides an 800G PAM4 signal compensation method based on channel crosstalk characteristics, which solves the problems that it is difficult to extract the channel crosstalk response generated by the transition of PAM4 level in adjacent channels and that it is difficult to recenter and adjust the PAM4 decision boundary with the compensation amount of the sampled value.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides an 800G PAM4 signal compensation method based on channel crosstalk characteristics, comprising: acquiring multi-channel PAM4 received sampling data within the same receiving compensation period; according to the sampling segments identified by the same PAM4 level of the compensated channel, recording the difference between the equalized PAM4 sample value and the corresponding PAM4 level center value as a sampling deviation; distinguishing between the same-level maintenance state of adjacent interfering channels and the PAM4 level pair transition state, forming a PAM4 transition response sampling record; using the sampling deviation in the same-level maintenance state of adjacent interfering channels in the PAM4 transition response sampling record as the same-level maintenance residual; calculating the difference between the sampling deviation in the PAM4 level pair transition state of adjacent interfering channels and the same-level maintenance residual to obtain the transition residual; extracting the channel crosstalk response according to the difference between the positive transition residual and the negative transition residual of the same PAM4 level pair, forming a channel crosstalk response record; generating a compensation amount of the sampled value in the PAM4 level pair transition state of adjacent interfering channels based on the channel crosstalk response record, and averaging the sampling values ​​on both sides of the PAM4 decision boundary. When calculating the sample value compensation amount, the PAM4 decision boundary after recentering is calculated using the center values ​​of the PAM4 levels on both sides and the compensation amount of the sampled values ​​on both sides. When the level on either side of the PAM4 decision boundary does not form a sampled value compensation amount, a PAM4 decision boundary retention value is formed, and a PAM4 signal compensation parameter record is formed. Based on the sampled value compensation amount in the PAM4 signal compensation parameter record, the equalized PAM4 sampled value of the compensated channel is corrected to obtain the compensated PAM4 sampled value. PAM4 decision is performed on the compensated PAM4 sampled value according to the recentered PAM4 decision boundary or the PAM4 decision boundary retention value, and a compensated PAM4 decision record is formed. The difference between the compensated PAM4 sampled value and the center value of the PAM4 level to which the compensated PAM4 decision level identifier belongs is recorded as the compensated residual. The compensated residual is incorporated into the PAM4 transition response sampling record of the next receiving compensation cycle. The channel crosstalk response record is updated according to the direction relationship of the compensated transition residual under the positive PAM4 level transition and the reverse PAM4 level transition.

[0008] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the multi-channel PAM4 received sampling data includes the compensated channel number, the adjacent interfering channel number, the PAM4 symbol number, the discrete sampling number, the sampling phase position, the sampling delay position, the equalized PAM4 sample value, the PAM4 decision level identifier of the compensated channel, and the PAM4 level identifier of the adjacent interfering channel.

[0009] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the step of dividing the sampled segments of the compensated channel that are at the same PAM4 level identifier into sampled segments of the same PAM4 level identifier and recording the difference between the equalized PAM4 sampled value and the corresponding PAM4 level center value as the sampling deviation, and distinguishing between the state of adjacent interfering channels maintaining the same level and the state of PAM4 level transition, to form a PAM4 transition response sampling record includes: dividing the sampled segments of the compensated channel that are at the same PAM4 level identifier based on the change position of the PAM4 decision level identifier of the compensated channel, and generating a sampling segment number; grouping the equalized PAM4 sampled values ​​according to the PAM4 decision level identifier of the compensated channel to obtain the PAM4 level center value, and recording the difference between the equalized PAM4 sampled value and the corresponding PAM4 level center value within the sampled segments of the compensated channel that are at the same PAM4 level identifier. The value is recorded as the sampling deviation. Based on the change relationship of the PAM4 level identifier of adjacent interference channels on two adjacent PAM4 symbols, the state change relationship of adjacent interference channels is marked as either the adjacent interference channels maintaining the same level or the adjacent interference channels PAM4 level pair switching state. In the state where the adjacent interference channels maintain the same level, the same maintaining PAM4 level identifier is formed. In the state where the adjacent interference channels PAM4 level pair switching state, the PAM4 level identifier before switching, the PAM4 level identifier after switching, the PAM4 level pair, and the PAM4 switching direction are formed. The sampling segment number, sampling deviation, state change relationship of adjacent interference channels, same maintaining PAM4 level identifier, PAM4 level pair, PAM4 level identifier before switching, PAM4 level identifier after switching, and PAM4 switching direction are organized to form the PAM4 switching response sampling record.

[0010] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the step of calculating the difference between the sampling deviation of adjacent interfering channels under the switching state and the same-level holding residual to obtain the switching residual includes: classifying PAM4 switching response sampling records with the same receiving compensation cycle number, compensated channel number, adjacent interfering channel number, compensated channel PAM4 decision level identifier, sampling phase position, and sampling delay position into the same type of sampling record; within the same type of sampling record, classifying the sampling deviation of adjacent interfering channels under the same-level holding state according to the same holding PAM4 level identifier. The single sampling deviation after division or the middle voltage position after sorting by voltage value is taken as the same level maintenance residual; within the same type of sampling record, according to the PAM4 level pair and PAM4 transition direction, the sampling deviation of the PAM4 level pair in the transition state of adjacent interference channels is divided, and the single sampling deviation after division or the middle voltage position after sorting by voltage value is taken as the transition state sampling deviation; the same level maintenance residual under the same maintenance PAM4 level identifier to which the PAM4 level identifier belongs before the transition is taken as the residual reference, and the difference between the transition state sampling deviation and the same level maintenance residual is recorded as the transition residual.

[0011] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the step of extracting the channel crosstalk response according to the difference between the positive transition residual and the negative transition residual of the same PAM4 level pair, and forming a channel crosstalk response record, includes: under the same type of sampling record and the same PAM4 level pair, dividing the transition residual based on the high-low relationship between the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition and the center value of the PAM4 level to which the PAM4 level identifier belongs after the transition; when the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition is lower than the center value of the PAM4 level to which the PAM4 level identifier belongs after the transition, the corresponding transition residual is recorded as a positive transition residual; when the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition is higher than the center value of the PAM4 level identifier after the transition, the corresponding transition residual is recorded as a positive transition residual; when the center value of the PAM4 level identifier belongs to which the PAM4 level identifier belongs is higher than the center value of the PAM4 level identifier after the transition, the positive transition residual is recorded as a negative transition residual. When the PAM4 level identifier after the transition is at its center value, the corresponding transition residual is recorded as the reverse transition residual. When both forward and reverse transition residuals exist under the same type of sampling record and the same PAM4 level pair, the forward transition residual is used as the comparison quantity, and the reverse transition residual is used as the comparison benchmark. Half of the difference between the forward transition residual and the reverse transition residual is recorded as the channel crosstalk response. According to the receiving compensation cycle number, the compensated channel number, the adjacent interference channel number, the compensated channel PAM4 decision level identifier, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction, the same level holding residual, the forward transition residual, the reverse transition residual, and the channel crosstalk response are written into the channel crosstalk response record.

[0012] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the formation of the PAM4 signal compensation parameter record includes: retrieving the channel crosstalk response from the channel crosstalk response record according to the receiving compensation cycle number, the compensated channel number, the adjacent interfering channel number, the compensated channel PAM4 decision level identifier, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction; when the PAM4 transition direction is a positive PAM4 level pair transition, the sign of the channel crosstalk response is inverted and used as the sampled value compensation amount .... When the PAM4 level transitions in the opposite direction, the channel crosstalk response is used as the sampled value compensation amount. Following the order of PAM4 level center values ​​from low to high, the intermediate voltage position between the center values ​​of the PAM4 level of two adjacent compensated channels is recorded as the PAM4 decision boundary. The PAM4 decision level markers of the compensated channels on both sides of the PAM4 decision boundary are respectively recorded as the low-side PAM4 level marker and the high-side PAM4 level marker. When both the low-side and high-side PAM4 level markers have formed sampled value compensation... During compensation, the center value of the PAM4 level corresponding to the low-side PAM4 level indicator is added to the compensation amount of the sampled value under the low-side PAM4 level indicator to obtain the low-side compensation center position. Similarly, the center value of the PAM4 level corresponding to the high-side PAM4 level indicator is added to the compensation amount of the sampled value under the high-side PAM4 level indicator to obtain the high-side compensation center position. When the low-side compensation center position is lower than the high-side compensation center position, the intermediate voltage position between the low-side and high-side compensation center positions is recorded as the re-centered PAM4 decision boundary; when the low-side PAM4 level... When the flat or high-side PAM4 level indicator does not form a sampled value compensation amount, or when the low-side compensation center position is not lower than the high-side compensation center position, the intermediate voltage position between the PAM4 level center value of the low-side PAM4 level indicator and the PAM4 level center value of the high-side PAM4 level indicator is recorded as the PAM4 decision boundary retention value; the sampled value compensation amount, the low-side PAM4 level indicator, the high-side PAM4 level indicator, and the re-centered PAM4 decision boundary or PAM4 decision boundary retention value are written into the PAM4 signal compensation parameter record.

[0013] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the following steps are included: forming a compensated PAM4 decision record: processing the equalized PAM4 sampled value of the compensated channel along the PAM4 symbol sequence number; when the state change relationship of the adjacent interference channel in the record to which the equalized PAM4 sampled value belongs is a transition state of the PAM4 level of the adjacent interference channel and the sampled value compensation amount and the recentered PAM4 decision boundary are found in the PAM4 signal compensation parameter record, the equalized PAM4 sampled value is added to the sampled value compensation amount to obtain the compensated PAM4 sampled value; when no sampled value compensation amount is found or the state change relationship of the adjacent interference channel is a state of maintaining the same level of the adjacent interference channel, or the PAM4 signal compensation parameter record contains a corresponding PAM4 decision boundary retention value, the equalized PAM4 sampled value is used as the compensated PAM4 sampled value; when the state change relationship of the adjacent interference channel corresponding to the compensated PAM4 sampled value is a transition state of the adjacent interference channel P... When the AM4 level is in a transition state, the re-centered PAM4 decision boundary or the PAM4 decision boundary retention value is retrieved from the PAM4 signal compensation parameter record as the current decision boundary between two adjacent PAM4 level identifiers. When the state change relationship of the adjacent interference channel corresponding to the compensated PAM4 sample value is that the adjacent interference channel maintains the same level, the current decision boundary is formed based on the center value of the PAM4 level to which the two adjacent PAM4 level identifiers belong. The compensated PAM4 sample value is compared with each current decision boundary to obtain the compensated PAM4 decision level identifier. The difference between the compensated PAM4 sample value and the center value of the PAM4 level to which the compensated PAM4 decision level identifier belongs is recorded as the compensated residual. The equalized PAM4 sample value, the sample value compensation amount, the compensated PAM4 sample value, the current decision boundary, the compensated PAM4 decision level identifier, and the compensated residual are written into the compensated PAM4 decision record.

[0014] As a preferred embodiment of the 800G PAM4 signal compensation method based on channel crosstalk characteristics described in this invention, the updated channel crosstalk response record includes: based on the compensated PAM4 decision record, when forming the PAM4 transition response sampling record in the next receiving compensation cycle, according to the compensated channel number, adjacent interfering channel number, compensated PAM4 decision level identifier, sampling phase position, sampling delay position, and adjacent interfering channel state change relationship, the compensated residual is incorporated into the PAM4 transition response sampling record under the same sampling conditions in the next receiving compensation cycle; in the incorporated PAM4 transition response sampling record, when the adjacent interfering channel state change relationship is the adjacent interfering channel maintaining the same level, the compensated residual is aggregated according to the same maintaining PAM4 level identifier to obtain the compensated same level maintaining residual; when the adjacent interfering channel state change relationship is the adjacent interfering channel PAM4 level pair transition state, the compensated residual is aggregated according to the PAM4 level pair and PAM4 transition direction to obtain the compensated transition... State residual; using the residual of the same level after compensation to which the PAM4 level identifier belongs before the transition as the residual reference, the difference between the state residual after compensation and the residual of the same level after compensation is recorded as the state residual after compensation; the condition that the compensated channel number, the adjacent interference channel number, the PAM4 decision level identifier after compensation, the sampling phase position, the sampling delay position, and the PAM4 level pair are all the same is recorded as the same residual comparison condition after compensation. Under the same residual comparison condition after compensation, when the residual after compensation under the positive PAM4 level pair transition and the residual after compensation under the negative PAM4 level pair transition exist simultaneously and are in opposite directions, half of the difference between the two is recorded as the channel crosstalk response margin, and the original channel crosstalk response in the channel crosstalk response record is added to the channel crosstalk response margin to obtain the updated channel crosstalk response; otherwise, the original channel crosstalk response in the channel crosstalk response record is retained; the updated channel crosstalk response or the original channel crosstalk response is written into the channel crosstalk response record.

[0015] In a second aspect, the present invention provides a computer device including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program is executed by the processor, it implements any step of the 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in the first aspect of the present invention.

[0016] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, it implements any step of the 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in the first aspect of the present invention.

[0017] The beneficial effects of this invention are as follows: by pairwise processing of residuals that maintain the same level, transition residuals, positive transition residuals, and negative transition residuals, the channel crosstalk response is separated from the transition state of the PAM4 level of adjacent interfering channels, so that the sampled value compensation amount has a clear directional source; by forming the recentered PAM4 decision boundary together with the sampled value compensation amount and the center values ​​of the PAM4 levels on both sides, the corresponding correction of the PAM4 sampled value and the decision boundary after compensation is realized, so that the PAM4 decision process is consistent with the channel crosstalk response record. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of an 800G PAM4 signal compensation method based on channel crosstalk characteristics.

[0020] Figure 2 A flowchart outlining the relationship between sampling deviation and changes in the state of adjacent interference channels.

[0021] Figure 3 A flowchart for extracting the channel crosstalk response while maintaining a residual reference at the same level.

[0022] Figure 4 This is a flowchart for updating the sampled value compensation amount, PAM4 decision boundary, and channel crosstalk response.

[0023] Figure 5 The simulation results are extracted for the channel crosstalk response under the same level and residual reference.

[0024] Figure 6 The simulation results of residual changes after compensation under the PAM4 decision boundary after recentering are shown in the figure. Detailed Implementation

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0028] Reference Figures 1-6 This is one embodiment of the present invention, which provides an 800G PAM4 signal compensation method based on channel crosstalk characteristics, comprising the following steps:

[0029] S1. Collect multi-channel PAM4 received sampling data within the same receiving compensation period. According to the sampling segments identified by the same PAM4 level of the compensated channel, record the difference between the equalized PAM4 sample value and the corresponding PAM4 level center value as the sampling deviation. Distinguish between the state of adjacent interference channels maintaining the same level and the state of PAM4 level switching, and form a PAM4 switching response sampling record.

[0030] Furthermore, in one embodiment, the 800G multi-channel PAM4 receiving link includes multiple parallel PAM4 receiving channels. 800G represents the total transmission rate level of the multi-channel PAM4 receiving link. PAM4 (4-Level Pulse Amplitude Modulation) is a four-level pulse amplitude modulation. The PAM4 signal carries symbol information through four amplitude levels. When the receiving end processes the multi-channel PAM4 received signal, it obtains the sampling time of each PAM4 symbol at the receiving end through clock recovery, obtains the equalized PAM4 sample value after channel attenuation and inter-symbol interference compensation through front-end equalization, and assigns the equalized PAM4 sample value to the four PAM4 level identifiers through PAM4 initial decision, thereby obtaining the multi-channel PAM4 received sample data within the same receiving compensation period.

[0031] Specifically, the multi-channel PAM4 received sampling data includes the compensated channel number, the adjacent interference channel number, the PAM4 symbol number, the discrete sampling number, the sampling phase position, the sampling delay position, the equalized PAM4 sample value, the PAM4 decision level identifier of the compensated channel, and the PAM4 level identifier of the adjacent interference channel.

[0032] Wherein, the receive compensation period represents the time range within which the receiver samples, organizes, and compensates a segment of PAM4 symbol sequence; the compensated channel represents the receiving channel currently performing PAM4 sample value compensation; the adjacent interference channel represents the receiving channel adjacent to the compensated channel and participating in crosstalk analysis; the PAM4 symbol sequence number represents the arrangement order of PAM4 symbols within the receive compensation period; the discrete sampling sequence number represents the sampling point order output by the receiver's sampling circuit; the sampling phase position represents the sampling position of the equalized PAM4 sample value within the PAM4 symbol period; the sampling delay position represents the sampling point position shifted forward or backward relative to the PAM4 symbol sampling time; the equalized PAM4 sample value represents the voltage sample value output after front-end equalization; the compensated channel PAM4 The decision level identifier indicates the four amplitude level categories into which the PAM4 sampled value of the compensated channel is classified after the initial PAM4 decision, and does not represent the voltage value itself. The adjacent interference channel PAM4 level identifier indicates the four amplitude level categories into which the PAM4 symbols of adjacent interference channels are classified within the same reception compensation period, and does not represent the voltage value itself. The PAM4 level identifier includes a first PAM4 level identifier, a second PAM4 level identifier, a third PAM4 level identifier, and a fourth PAM4 level identifier. The first PAM4 level identifier to the fourth PAM4 level identifier are arranged in ascending order of the center value of each PAM4 level within the same reception compensation period. The PAM4 level identifier only indicates the PAM4 amplitude level category and does not represent the specific voltage value.

[0033] Furthermore, within the receive compensation period, the PAM4 decision level identifier of the compensated channel is read along the PAM4 symbol sequence number. When the PAM4 decision level identifiers of the compensated channel on two adjacent PAM4 symbols are different, it indicates that the compensated channel has undergone PAM4 level switching between the two adjacent PAM4 symbols. The position between the two adjacent PAM4 symbols is taken as the sampling segment boundary, and the start position and end position of the receive compensation period are taken as the sampling segment boundary. The PAM4 decision level identifiers of the compensated channel between the boundaries of two adjacent sampling segments are kept in the same sampling range and recorded as the sampling segment of the compensated channel with the same PAM4 level identifier. The sampling segment number is generated according to the arrangement order of the sampling segments of the compensated channel with the same PAM4 level identifier within the receive compensation period.

[0034] The sampling segments of the compensated channel that are in the same PAM4 level identifier indicate the sampling range in which the compensated channel has not undergone PAM4 level switching.

[0035] Furthermore, within the receiving compensation period, the equalized PAM4 sampled values ​​of the compensated channel are grouped according to the PAM4 decision level identifier of the compensated channel to obtain the center value of the PAM4 level under the PAM4 decision level identifier of each compensated channel.

[0036] When there is no equalized PAM4 sample value under the PAM4 decision level identifier of the same compensated channel, no corresponding PAM4 level center value is formed in the current receiving compensation period; when there is one equalized PAM4 sample value under the PAM4 decision level identifier of the same compensated channel, the equalized PAM4 sample value is taken as the PAM4 level center value; when there are two or more equalized PAM4 sample values ​​under the PAM4 decision level identifier of the same compensated channel, the two or more equalized PAM4 sample values ​​are arranged in ascending order of voltage value; when the number of equalized PAM4 sample values ​​is odd, the equalized PAM4 sample value in the middle position of the arrangement is taken as the PAM4 level center value; when the number of equalized PAM4 sample values ​​is even, the middle voltage position between the two equalized PAM4 sample values ​​located in the middle of the arrangement is taken as the PAM4 level center value.

[0037] It should be noted that the center value of the PAM4 level represents the main concentration position of the sampled voltage under the PAM4 decision level identifier of the same compensated channel; the initial PAM4 decision will classify the equalized PAM4 sampled values ​​into four PAM4 level identifiers, and the equalized PAM4 sampled values ​​under the same PAM4 level identifier are usually distributed within a voltage range; using the middle voltage position as the center value of the PAM4 level ensures that the center value of the PAM4 level falls in the middle position of the sampled voltage sequence under the same PAM4 level identifier; the maximum voltage value, minimum voltage value, or a single initial sampled value are likely to fall at the edge of the sampled voltage range and are not suitable as voltage references for sampling deviation under the same PAM4 level identifier.

[0038] Furthermore, within the sampling segment of the compensated channel that is in the same PAM4 level identifier, for the PAM4 decision level identifier of the compensated channel that has formed the PAM4 level center value, the equalized PAM4 sample value under each discrete sampling sequence number and sampling phase position is compared with the PAM4 level center value under the PAM4 decision level identifier of the corresponding compensated channel, and the difference between the equalized PAM4 sample value and the PAM4 level center value is recorded as the sampling deviation.

[0039] Sampling deviation represents the voltage offset of the equalized PAM4 sample value relative to the center value of the PAM4 level after compensation. The unit of sampling deviation is the same as the unit of the equalized PAM4 sample value.

[0040] Furthermore, within the sampling segment where the compensated channel is in the same PAM4 level identifier, the PAM4 level identifier of the adjacent interference channel is read along the PAM4 symbol sequence number, and the PAM4 level identifiers of the adjacent interference channels on two adjacent PAM4 symbols are compared.

[0041] When the PAM4 level identifiers of adjacent interference channels on two adjacent PAM4 symbols are the same, it indicates that no PAM4 level switching has occurred between the two adjacent PAM4 symbols. The state change relationship of adjacent interference channels is marked as the adjacent interference channels maintaining the same level. The same PAM4 level identifiers of adjacent interference channels are recorded as the same maintaining PAM4 level identifiers. The sampling deviation of the compensated channel under the same sampling segment, the same sampling phase position, and the same sampling delay position is associated with the adjacent interference channels maintaining the same level and the same maintaining PAM4 level identifiers.

[0042] When the PAM4 level identifiers of adjacent interference channels on two adjacent PAM4 symbols are different, it indicates that the PAM4 level of the adjacent interference channels has switched between two adjacent PAM4 symbols. The state change relationship of the adjacent interference channels is marked as the PAM4 level switching state of the adjacent interference channels. The PAM4 level identifier of the adjacent interference channel on the previous PAM4 symbol is recorded as the PAM4 level identifier before the switch, and the PAM4 level identifier of the adjacent interference channel on the current PAM4 symbol is recorded as the PAM4 level identifier after the switch.

[0043] The combination of the two PAM4 level identifiers corresponding to the PAM4 level identifier before and after the transition is denoted as a PAM4 level pair. The PAM4 level pair is used to identify the two PAM4 level identifiers that have transitioned, and does not indicate the transition direction alone. The relationship between the PAM4 level identifier before and after the transition is denoted as the PAM4 transition direction. When the center value of the PAM4 level identifier before the transition is lower than the center value of the PAM4 level identifier after the transition, the PAM4 transition direction is denoted as a positive PAM4 level pair transition. When the center value of the PAM4 level identifier before the transition is higher than the center value of the PAM4 level identifier after the transition, the PAM4 transition direction is denoted as a negative PAM4 level pair transition.

[0044] Furthermore, according to the receiving compensation cycle number, the compensated channel number, the adjacent interference channel number, the sampling segment number, the PAM4 symbol sequence number, the discrete sampling sequence number, the sampling phase position, and the sampling delay position, the PAM4 decision level identifier of the compensated channel, the equalized PAM4 sample value, the PAM4 level center value, the sampling deviation, the relationship of the state change of the adjacent interference channel, the same held PAM4 level identifier, the PAM4 level pair, the PAM4 level identifier before the transition, the PAM4 level identifier after the transition, the PAM4 transition direction, and the compensation residual incorporated in the previous receiving compensation cycle are organized to form a PAM4 transition response sampling record.

[0045] When the state change relationship between adjacent interference channels is that the adjacent interference channels maintain the same level, the PAM4 transition response sampling record records the same PAM4 level identifier; when the state change relationship between adjacent interference channels is that the PAM4 level pair of adjacent interference channels transitions, the PAM4 transition response sampling record records the PAM4 level pair, the PAM4 level identifier before the transition, the PAM4 level identifier after the transition, and the PAM4 transition direction; when there is no post-compensation residual incorporated in the previous receiving compensation cycle, the post-compensation residual incorporated in the previous receiving compensation cycle in the PAM4 transition response sampling record is empty.

[0046] The PAM4 transition response sampling record represents the relationship between the sampling deviation of the compensated channel and the state change of adjacent interfering channels within the sampling segment marked by the same PAM4 level in the compensated channel. It is used to carry over the post-compensation residual formed under the same sampling conditions in the previous receiving compensation cycle.

[0047] S2. The sampling deviation of adjacent interference channels in the same level holding state in the PAM4 transition response sampling record is taken as the same level holding residual. The difference between the sampling deviation of adjacent interference channels in the PAM4 level pair transition state and the same level holding residual is calculated to obtain the transition residual. The channel crosstalk response is extracted according to the difference between the positive transition residual and the negative transition residual of the same PAM4 level pair to form the channel crosstalk response record.

[0048] Furthermore, the PAM4 transition response sampling records are categorized according to the receiving compensation cycle number, the compensated channel number, the adjacent interference channel number, the PAM4 decision level identifier of the compensated channel, the sampling phase position, and the sampling delay position. PAM4 transition response sampling records with the same receiving compensation cycle number, compensated channel number, adjacent interference channel number, PAM4 decision level identifier of the compensated channel, sampling phase position, and sampling delay position are grouped into the same category of sampling records. Within the same category of sampling records, the sampling deviation is divided into the sampling deviation when the adjacent interference channels maintain the same level and the sampling deviation when the PAM4 level of the adjacent interference channels changes during the transition state, based on the relationship between the states of the adjacent interference channels.

[0049] The fact that the received compensation cycle number, compensated channel number, adjacent interference channel number, compensated channel PAM4 decision level identifier, sampling phase position, and sampling delay position are all the same indicates that the same level holding residual and the jumping residual are compared under the same compensated channel sampling conditions.

[0050] Furthermore, when adjacent interference channels maintain the same level in the same type of sampling record, the sampling deviations of adjacent interference channels in the same level maintenance state are divided according to the PAM4 level identifiers maintained by the adjacent interference channels on two adjacent PAM4 symbols; when there is only one sampling deviation under the same PAM4 level identifier, the single sampling deviation is taken as the same level maintenance residual; when there are two or more sampling deviations under the same PAM4 level identifier and the number is odd, the two or more sampling deviations are arranged in ascending order of voltage value, and the sampling deviation in the middle position of the arrangement is taken as the same level maintenance residual; when there are two or more sampling deviations under the same PAM4 level identifier and the number is even, the middle voltage position between the two sampling deviations located in the middle of the sort is taken as the same level maintenance residual.

[0051] The same level retention residual means that when there is no PAM4 level switching between adjacent interference channels, the sampling deviation of the compensated channel is referenced by the residual under the same compensated channel sampling conditions.

[0052] It should be noted that the same PAM4 level identifier indicates that the adjacent interference channels have the same PAM4 level identifier on two adjacent PAM4 symbols, and the same PAM4 level identifier of the adjacent interference channels is used as the aggregation identifier of the same level holding residual; the same level holding residual under different PAM4 level identifiers is used as the residual reference of the jump residual with the same PAM4 level identifier as the PAM4 level identifier before the jump; when the adjacent interference channels are held at different PAM4 level identifiers, the static offset reference in the sampling deviation of the compensated channel is different, so the same level holding residual is not combined for calculation.

[0053] Furthermore, when there are adjacent interference channel PAM4 level pair transition states in the same type of sampling record, the sampling deviation of the adjacent interference channel PAM4 level pair transition states is divided according to the PAM4 level pair and the PAM4 transition direction.

[0054] When there is only one sampling deviation for the same PAM4 level pair and the same PAM4 switching direction, the sampling deviation is taken as the switching state sampling deviation. When there are two or more sampling deviations for the same PAM4 level pair and the same PAM4 switching direction and the number is odd, the two or more sampling deviations are arranged in ascending order of voltage value, and the sampling deviation in the middle of the arrangement is taken as the switching state sampling deviation. When there are two or more sampling deviations for the same PAM4 level pair and the same PAM4 switching direction and the number is even, the middle voltage position between the two sampling deviations located in the middle of the arrangement is taken as the switching state sampling deviation.

[0055] Furthermore, using the same level maintenance residual of the adjacent interference channel to which the PAM4 level identifier belongs before the jump as the residual reference, the difference between the sampling deviation of the jump state and the same level maintenance residual is recorded as the jump residual.

[0056] The transition residual represents the change in the sampling deviation of the compensated channel relative to the state where the adjacent interference channel maintains the same level when the PAM4 level indicator changes from before the transition to after the transition in the adjacent interference channel.

[0057] It should be noted that when there is no same level maintenance residual under the same holding PAM4 level identifier to which the PAM4 level identifier belongs before the jump in the same type of sampling record, the jump residual is not calculated, and the sampling deviation of the PAM4 level of the adjacent interference channel under the jump state is retained.

[0058] Furthermore, when there are both positive PAM4 level pair transition residuals and negative PAM4 level pair transition residuals in the same type of sampling record under the same PAM4 level pair, the positive PAM4 level pair transition residual is recorded as the positive transition residual, and the negative PAM4 level pair transition residual is recorded as the negative transition residual.

[0059] Using the forward transition residual as the comparison quantity and the reverse transition residual as the comparison benchmark, the difference between the forward transition residual and the reverse transition residual is calculated, and half of the difference between the forward transition residual and the reverse transition residual is recorded as the channel crosstalk response. The channel crosstalk response represents the directional voltage influence of adjacent interfering channels on the sampling deviation of the compensated channel when a PAM4 transition occurs at the same PAM4 level. The unit of the channel crosstalk response is consistent with the unit of the sampling deviation.

[0060] It should be noted that the forward transition residual and the reverse transition residual are compared in pairs using the same PAM4 level pair, the same compensated channel number, the same adjacent interference channel number, the same compensated channel PAM4 decision level identifier, the same sampling phase position, and the same sampling delay position, so that the forward transition residual and the reverse transition residual are under the same compensated channel sampling conditions; the same level holding residual has been used as a residual reference to separate the static offset of the adjacent interference channel when no PAM4 level switching has occurred from the transition state sampling deviation. The difference between the forward transition residual and the reverse transition residual mainly comes from the directional influence of the same PAM4 level pair on the sampling deviation of the compensated channel under opposite PAM4 transition directions; the forward PAM4 level pair transition and the reverse PAM4 level pair transition belong to opposite change directions of the same PAM4 level pair, and the transition influence directions under the two directions are opposite. Therefore, half of the difference between the forward transition residual and the reverse transition residual is recorded as the channel crosstalk response, which is used to characterize the directional voltage influence of the adjacent interference channel on the compensated channel under a single PAM4 transition direction.

[0061] It should also be noted that when the same type of sampling record lacks a positive transition residual or a negative transition residual, the channel crosstalk response is not extracted, but the already formed transition residual is retained. The retained transition residual is used for tracing the source of the residual in the channel crosstalk response record, and is not used as the basis for generating the sampled value compensation amount. When the positive transition residual and the negative transition residual do not belong to the same compensated channel PAM4 decision level identifier, the same sampling phase position, or the same sampling delay position, they are sorted separately according to different compensated channel PAM4 decision level identifiers, different sampling phase positions, or different sampling delay positions, and are not compared in pairs.

[0062] Furthermore, based on the received compensation cycle number, the compensated channel number, the adjacent interference channel number, the PAM4 decision level identifier of the compensated channel, the sampling phase position, the sampling delay position, and the PAM4 level pair, the same level holding residual, the positive transition residual, the negative transition residual, the PAM4 transition direction, and the channel crosstalk response are summarized to form a channel crosstalk response record.

[0063] The channel crosstalk response record represents the recorded relationship between the PAM4 level transition of adjacent interfering channels and the change in sampling deviation of the compensated channel, under the condition that the sampling conditions of the compensated channel are consistent.

[0064] S3. Generate the sampled value compensation amount of the PAM4 level of the adjacent interference channel under the jumping state according to the channel crosstalk response record. When the average level on both sides of the PAM4 decision boundary has formed the sampled value compensation amount, calculate the re-centered PAM4 decision boundary with the center value of the PAM4 level on both sides and the sampled value compensation amount on both sides. When the level on either side of the PAM4 decision boundary has not formed the sampled value compensation amount, form the PAM4 decision boundary retention value and form the PAM4 signal compensation parameter record.

[0065] Furthermore, in the channel crosstalk response record, the channel crosstalk response is retrieved according to the receiving compensation cycle number, the compensated channel number, the adjacent interfering channel number, the PAM4 decision level identifier of the compensated channel, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction. Based on the PAM4 transition direction, the sampled value compensation amount of the adjacent interfering channel PAM4 level pair in the transition state is generated.

[0066] When the PAM4 transition direction is a positive PAM4 level pair transition, the sign of the channel crosstalk response is inverted and used as the sample value compensation amount under a positive PAM4 level pair transition; when the PAM4 transition direction is a negative PAM4 level pair transition, the channel crosstalk response is used as the sample value compensation amount under a negative PAM4 level pair transition. The sample value compensation amount represents the sample voltage correction amount to offset the influence of adjacent interfering channel PAM4 levels on the transition directional voltage, and the unit of the sample value compensation amount is consistent with the unit of the channel crosstalk response.

[0067] It should be noted that the channel crosstalk response has been extracted from the paired comparisons of the positive PAM4 level to the transition and the negative PAM4 level to the transition. The directional voltage influence of the positive PAM4 level to the transition is in the same direction as the channel crosstalk response, while the directional voltage influence of the negative PAM4 level to the transition is in the opposite direction to the channel crosstalk response. Therefore, the sample value compensation amount under the positive PAM4 level to the transition adopts the inverse vector of the channel crosstalk response, and the sample value compensation amount under the negative PAM4 level to the transition adopts the same vector of the channel crosstalk response, so that the sample value compensation amount is opposite to the direction of the sampling deviation change caused by the PAM4 level to the transition of adjacent interfering channels.

[0068] Furthermore, according to the ascending order of the center values ​​of the PAM4 levels belonging to the PAM4 decision level identifiers of the compensated channels, the intermediate voltage position between the center values ​​of the PAM4 levels belonging to the PAM4 decision level identifiers of two adjacent compensated channels is recorded as the PAM4 decision boundary. The PAM4 decision level identifiers of the compensated channels on both sides of the PAM4 decision boundary are respectively recorded as the low-side PAM4 level identifier and the high-side PAM4 level identifier. The PAM4 decision boundary represents the voltage boundary position between two adjacent compensated channel PAM4 decision level identifiers that distinguishes the PAM4 sample value.

[0069] Furthermore, under the same receiving compensation cycle number, the same compensated channel number, the same adjacent interference channel number, the same sampling phase position, the same sampling delay position, the same PAM4 level pair, and the same PAM4 switching direction, the sample value compensation amount under the low-side PAM4 level identifier and the sample value compensation amount under the high-side PAM4 level identifier are respectively searched.

[0070] When both the low-side PAM4 level marker and the high-side PAM4 level marker have formed sampled value compensation amounts, the center value of the PAM4 level to which the low-side PAM4 level marker belongs is added to the sampled value compensation amount under the low-side PAM4 level marker to obtain the low-side compensation center position; the center value of the PAM4 level to which the high-side PAM4 level marker belongs is added to the sampled value compensation amount under the high-side PAM4 level marker to obtain the high-side compensation center position; when the low-side compensation center position is lower than the high-side compensation center position, the intermediate voltage position between the low-side compensation center position and the high-side compensation center position is recorded as the PAM4 decision boundary after recentering.

[0071] When neither the low-side PAM4 level indicator nor the high-side PAM4 level indicator has formed a sampled value compensation amount, the intermediate voltage position between the center value of the PAM4 level to which the low-side PAM4 level indicator belongs and the center value of the PAM4 level to which the high-side PAM4 level indicator belongs is recorded as the PAM4 decision boundary retention value; when both the low-side PAM4 level indicator and the high-side PAM4 level indicator have formed sampled value compensation amounts, and the center position of the low-side compensation is not lower than the center position of the high-side compensation, the intermediate voltage position between the center value of the PAM4 level to which the low-side PAM4 level indicator belongs and the center value of the PAM4 level to which the high-side PAM4 level indicator belongs is recorded as the PAM4 decision boundary retention value.

[0072] It should be noted that the PAM4 decision boundary after recentering is not simply moved from the original PAM4 decision boundary. Instead, the center values ​​of the PAM4 levels on both sides are corrected based on the sampled value compensation amounts under the low-side PAM4 level indicator and the high-side PAM4 level indicator, and then the PAM4 decision boundary is re-formed with the corrected center positions of the voltages on both sides. When either side lacks a sampled value compensation amount, the center positions of the voltages on both sides lack a paired correction basis. When the low-side compensation center position is not lower than the high-side compensation center position, the center positions of the compensations on both sides do not satisfy the voltage arrangement relationship from the low-side PAM4 level indicator to the high-side PAM4 level indicator. Therefore, the PAM4 decision boundary formed by the center values ​​of the PAM4 levels on both sides is retained.

[0073] Furthermore, based on the received compensation cycle number, the compensated channel number, the adjacent interference channel number, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction, the PAM4 decision level identifier of the compensated channel, the sampled value compensation amount, the low-side PAM4 level identifier, the high-side PAM4 level identifier, the formed low-side sampled value compensation amount, the formed high-side sampled value compensation amount, the formed low-side compensation center position, the formed high-side compensation center position, and the PAM4 decision boundary or PAM4 decision boundary retention value after recentering are summarized to form a PAM4 signal compensation parameter record.

[0074] When both the low-side PAM4 level indicator and the high-side PAM4 level indicator have formed sampled value compensation, and the low-side compensation center position is lower than the high-side compensation center position, the PAM4 signal compensation parameter record records the PAM4 decision boundary after recentering; when neither the low-side PAM4 level indicator nor the high-side PAM4 level indicator has formed sampled value compensation, or when both the low-side PAM4 level indicator and the high-side PAM4 level indicator have formed sampled value compensation but the low-side compensation center position is not lower than the high-side compensation center position, the PAM4 signal compensation parameter record records the PAM4 decision boundary retention value.

[0075] The PAM4 signal compensation parameter record represents the relationship between the sampled voltage correction amount and the decision boundary voltage position of the compensated channel under the transition state of the PAM4 level of the adjacent interference channel; the sampled value compensation amount serves as the correction parameter of the equalized PAM4 sampled value, and the recentered PAM4 decision boundary or the PAM4 decision boundary retention value serves as the decision parameter of the compensated PAM4 sampled value.

[0076] S4. Based on the compensation amount of the sampled value in the PAM4 signal compensation parameter record, correct the equalized PAM4 sampled value of the compensated channel to obtain the compensated PAM4 sampled value. Perform PAM4 decision on the compensated PAM4 sampled value according to the recentered PAM4 decision boundary or the PAM4 decision boundary retention value to form a compensated PAM4 decision record. Record the difference between the compensated PAM4 sampled value and the center value of the PAM4 level to which the compensated PAM4 decision level identifier belongs as the compensated residual. Incorporate the compensated residual into the PAM4 transition response sampling record of the next receiving compensation cycle. Update the channel crosstalk response record according to the direction relationship of the compensated transition residual under the positive PAM4 level transition and the reverse PAM4 level transition.

[0077] Furthermore, after the PAM4 signal compensation parameter record is formed, the equalized PAM4 sampled values ​​of the compensated channel are processed along the PAM4 symbol sequence.

[0078] When the state change relationship of the adjacent interference channel in the record to which the equalized PAM4 sample value belongs is a PAM4 level pair transition state of the adjacent interference channel, the sample value compensation amount and the PAM4 decision boundary or PAM4 decision boundary retention value corresponding to the sample value compensation amount are searched in the PAM4 signal compensation parameter record according to the receiving compensation cycle number, the compensated channel number, the adjacent interference channel number, the compensated channel PAM4 decision level identifier, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction. When the sample value compensation amount and the PAM4 decision boundary corresponding to the sample value compensation amount are found, the equalized PAM4 sample value and the sample value compensation amount are added to obtain the compensated PAM4 sample value. When the sample value compensation amount is not found, or the PAM4 decision boundary retention value corresponding to the sample value compensation amount is found, the equalized PAM4 sample value is used as the compensated PAM4 sample value, and the sample value compensation amount field in the compensated PAM4 decision record is recorded as zero.

[0079] When the state change relationship of the adjacent interference channels in the record to which the equalized PAM4 sample value belongs is that the adjacent interference channels maintain the same level, the compensation amount of the sample value in the jumping state of the adjacent interference channel PAM4 level is not called. The equalized PAM4 sample value is used as the compensated PAM4 sample value, and the sample value compensation amount field in the compensated PAM4 decision record is recorded as zero.

[0080] It should be noted that the sample value compensation amount is the sample voltage correction amount. The PAM4 sample value after equalization is added to the sample value compensation amount to obtain the compensated PAM4 sample value. If the sample value compensation amount is not found, or if the adjacent interference channel does not have a PAM4 level transition, or if the PAM4 signal compensation parameter record records the PAM4 decision boundary retention value, the PAM4 sample value after equalization will not be included in the transition compensation correction.

[0081] Furthermore, when the state change relationship of the adjacent interference channel in the record to which the equalized PAM4 sample value belongs after compensation is the PAM4 level pair switching state of the adjacent interference channel, according to the receiving compensation cycle number, the compensated channel number, the adjacent interference channel number, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 switching direction, respectively search the PAM4 signal compensation parameter record for the following: the low-side PAM4 level identifier is the first PAM4 level identifier and the high-side PAM4 level identifier is the second PAM4 level identifier; the low-side PAM4 level identifier is the second PAM4 level identifier and the high-side PAM4 level identifier is the third PAM4 level identifier; and the low-side PAM4 level identifier is the third PAM4 level identifier and the high-side PAM4 level identifier is the fourth PAM4 level identifier.

[0082] When the PAM4 signal compensation parameter record contains the recentered PAM4 decision boundary, the recentered PAM4 decision boundary is used as the current decision boundary between two adjacent PAM4 level indicators; when the PAM4 signal compensation parameter record contains the PAM4 decision boundary retention value, the PAM4 decision boundary retention value is used as the current decision boundary between two adjacent PAM4 level indicators.

[0083] When the state change relationship of adjacent interference channels in the record of the equalized PAM4 sample value corresponding to the compensated PAM4 sample value is that the adjacent interference channels maintain the same level, according to the arrangement order of the PAM4 level center value from low to high, the intermediate voltage position between the PAM4 level marker and the PAM4 level center value of the first PAM4 level marker and the second PAM4 level marker is taken as the current decision boundary between the first PAM4 level marker and the second PAM4 level marker, the intermediate voltage position between the PAM4 level marker and the PAM4 level center value of the second PAM4 level marker and the third PAM4 level marker is taken as the current decision boundary between the second PAM4 level marker and the third PAM4 level marker, and the intermediate voltage position between the PAM4 level marker and the PAM4 level center value of the third PAM4 level marker and the fourth PAM4 level marker is taken as the current decision boundary between the third PAM4 level marker and the fourth PAM4 level marker.

[0084] Furthermore, the compensated PAM4 sample value is compared with three current decision boundaries. When the compensated PAM4 sample value is lower than or equal to the current decision boundary between the first and second PAM4 level markers, the compensated PAM4 decision level marker is recorded as the first PAM4 level marker. When the compensated PAM4 sample value is higher than the current decision boundary between the first and second PAM4 level markers, and lower than or equal to the current decision boundary between the second and third PAM4 level markers, the compensated PAM4 decision level is set. The level identifier is recorded as the second PAM4 level identifier; when the compensated PAM4 sample value is higher than the current decision boundary between the second PAM4 level identifier and the third PAM4 level identifier, and lower than or equal to the current decision boundary between the third PAM4 level identifier and the fourth PAM4 level identifier, the compensated PAM4 decision level identifier is recorded as the third PAM4 level identifier; when the compensated PAM4 sample value is higher than the current decision boundary between the third PAM4 level identifier and the fourth PAM4 level identifier, the compensated PAM4 decision level identifier is recorded as the fourth PAM4 level identifier.

[0085] Furthermore, according to the PAM4 decision level identifier after compensation, the center value of the PAM4 level to which the PAM4 decision level identifier belongs is found within the current receiving compensation period. The difference between the PAM4 sample value after compensation and the center value of the PAM4 level to which the PAM4 decision level identifier belongs is recorded as the residual after compensation. The unit of the residual after compensation is the same as the unit of the sample value after compensation.

[0086] The compensation PAM4 decision record is formed by summarizing the following information: received compensation cycle number, compensated channel number, adjacent interference channel number, compensated channel PAM4 decision level identifier, PAM4 symbol sequence number, discrete sampling sequence number, sampling phase position, sampling delay position, adjacent interference channel state change relationship, same hold PAM4 level identifier, PAM4 level pair and PAM4 transition direction, equalized PAM4 sampled value, sampled value compensation amount, compensated PAM4 sampled value, current decision boundary between the first PAM4 level identifier and the second PAM4 level identifier, current decision boundary between the second PAM4 level identifier and the third PAM4 level identifier, current decision boundary between the third PAM4 level identifier and the fourth PAM4 level identifier, compensated PAM4 decision level identifier and compensated residual.

[0087] When the state change relationship between adjacent interference channels is such that the adjacent interference channels maintain the same level, the compensated PAM4 decision record records the same maintained PAM4 level identifier; when the state change relationship between adjacent interference channels is such that the PAM4 level pair of adjacent interference channels jumps, the compensated PAM4 decision record records the PAM4 level pair and the PAM4 jump direction.

[0088] Furthermore, when forming the PAM4 transition response sampling record in the next reception compensation cycle, the compensated residual in the compensated PAM4 decision record is incorporated into the PAM4 transition response sampling record of the next reception compensation cycle according to the compensated channel number, adjacent interference channel number, PAM4 decision level identifier of the compensated channel, sampling phase position, sampling delay position, and the relationship between the state changes of adjacent interference channels.

[0089] When the state change relationship between adjacent interference channels is that the adjacent interference channels maintain the same level, the compensated residual is incorporated into the record of the same level maintenance state of adjacent interference channels under the same sampling conditions in the next receiving compensation cycle, according to the compensated channel number, adjacent interference channel number, PAM4 decision level identifier of the compensated channel, sampling phase position, sampling delay position, and the same PAM4 level identifier recorded in the compensated PAM4 decision record. When the state change relationship between adjacent interference channels is that the adjacent interference channels PAM4 level pair jumps, the compensated residual is incorporated into the record of the PAM4 level pair jumps state of adjacent interference channels under the same sampling conditions in the next receiving compensation cycle, according to the compensated channel number, adjacent interference channel number, PAM4 decision level identifier of the compensated channel, sampling phase position, sampling delay position, PAM4 level pair, and PAM4 jump direction.

[0090] It should be noted that when the compensated residual is incorporated into the PAM4 transition response sampling record of the next receiving compensation cycle, it does not replace the equalized PAM4 sampled value, sampling deviation, and adjacent interference channel state change relationship obtained by re-acquiring in the next receiving compensation cycle. Instead, it is written into the PAM4 transition response sampling record under the same sampling conditions as the compensated residual incorporated in the previous receiving compensation cycle and stored together. The compensated residual is used to check whether the directional residual caused by the transition of the PAM4 level of the adjacent interference channel still exists after the sampled value compensation amount and decision boundary participate in the compensation decision.

[0091] Furthermore, in the merged PAM4 switching response sampling records, the values ​​of the compensated residuals under the same aggregation conditions are processed. When there is only one compensated residual under the same aggregation conditions, one compensated residual is taken. When there are two or more compensated residuals under the same aggregation conditions and the number is odd, the two or more compensated residuals are arranged in ascending order of voltage value, and the compensated residual in the middle position of the arrangement is taken. When there are two or more compensated residuals under the same aggregation conditions and the number is even, the middle voltage position between the two compensated residuals located in the middle of the arrangement is taken.

[0092] When the state change relationship between adjacent interference channels is that the adjacent interference channels maintain the same level, the compensated channel number, the adjacent interference channel number, the compensated channel PAM4 decision level identifier, the sampling phase position, the sampling delay position, and the same PAM4 level identifier are used as the same settling condition, and the value is processed according to the value under the same settling condition to obtain the compensated same level maintenance residual; when the state change relationship between adjacent interference channels is that the adjacent interference channel PAM4 level pair jumps, the compensated channel number, the adjacent interference channel number, the compensated channel PAM4 decision level identifier, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 jump direction are used as the same settling condition, and the value is processed according to the value under the same settling condition to obtain the compensated jump state residual.

[0093] Furthermore, using the residual of the same level after compensation to which the PAM4 level identifier belongs before the transition as the residual reference, the difference between the residual of the transition state after compensation and the residual of the same level after compensation is recorded as the residual of the transition after compensation.

[0094] When there is no residual after compensation to which the PAM4 level identifier before the transition belongs, the residual after compensation is not calculated, and the residual after compensation of the PAM4 level of the adjacent interference channel in the transition state is retained.

[0095] Furthermore, the condition that the compensated channel number, adjacent interference channel number, compensated PAM4 decision level identifier, sampling phase position, sampling delay position, and PAM4 level pair are all the same is recorded as the same post-compensation residual comparison condition; when the same post-compensation residual comparison condition exists simultaneously with the post-compensation transition residual under the positive PAM4 level pair transition and the post-compensation transition residual under the negative PAM4 level pair transition, the directional relationship between the post-compensation transition residual under the positive PAM4 level pair transition and the post-compensation transition residual under the negative PAM4 level pair transition is determined.

[0096] When the residual error of the positive PAM4 level after compensation for the transition is greater than zero and the residual error of the negative PAM4 level after compensation for the transition is less than zero, or when the residual error of the positive PAM4 level after compensation for the transition is less than zero and the residual error of the negative PAM4 level after compensation for the transition is greater than zero, the two are determined to be in opposite directions; when both the residual error of the positive PAM4 level after compensation for the transition and the residual error of the negative PAM4 level after compensation for the transition are greater than zero or both are less than zero, the two are determined to be in the same direction; when either the residual error of the positive PAM4 level after compensation for the transition or the residual error of the negative PAM4 level after compensation for the transition is equal to zero, the two are determined not to meet the condition of being extracted in pairs in opposite directions.

[0097] When the direction of the compensated transition residual under the positive PAM4 level transition is opposite to that of the compensated transition residual under the negative PAM4 level transition, the compensated transition residual under the positive PAM4 level transition is used as the comparison quantity, and the compensated transition residual under the negative PAM4 level transition is used as the comparison benchmark. Half of the difference between the compensated transition residual under the positive PAM4 level transition and the compensated transition residual under the negative PAM4 level transition is recorded as the channel crosstalk response margin. The original channel crosstalk response in the channel crosstalk response record is added to the channel crosstalk response margin to obtain the updated channel crosstalk response.

[0098] When the direction of the compensated transition residual under the positive PAM4 level is the same as that under the negative PAM4 level, or either of the compensated transition residuals is equal to zero, or when the compensated transition residuals under the same condition of comparison are missing, the original channel crosstalk response in the channel crosstalk response record is retained.

[0099] It should be noted that the post-compensation transition residual is used to reflect the directional residuals still retained under positive and negative PAM4 level pairs after the sampled value compensation amount, the PAM4 decision boundary after recentering, or the PAM4 decision boundary retained value participates in the compensation decision. Only when the post-compensation transition residuals under positive and negative PAM4 level pairs under the same post-compensation residual comparison conditions are both non-zero and opposite in direction, will the post-compensation residual still exhibit the residual directional voltage influence that can be extracted in pairs. Therefore, the channel crosstalk response margin is used to correct the channel crosstalk response record. When the directions are the same, either is zero, or one side of the post-compensation transition residual is missing under the same post-compensation residual comparison conditions, the post-compensation residual does not satisfy the opposite directional relationship between positive and negative PAM4 level pairs, and therefore the channel crosstalk response record is not corrected.

[0100] Furthermore, the original channel crosstalk response, channel crosstalk response margin, updated channel crosstalk response, post-compensation PAM4 decision level identifier, sampling phase position, sampling delay position, PAM4 level pair, and PAM4 transition direction are summarized and written into the channel crosstalk response record according to the receiving compensation cycle number, compensated channel number, adjacent interference channel number, post-compensation PAM4 decision level identifier, sampling phase position, sampling delay position, PAM4 level pair, and PAM4 transition direction.

[0101] The updated channel crosstalk response is used as input for generating the PAM4 signal compensation parameter record in the next receive compensation cycle; if no channel crosstalk response margin is formed, the channel crosstalk response record retains the original channel crosstalk response.

[0102] It should also be noted that, in order to verify the channel crosstalk response extraction effect under the same level and residual reference, and to verify the improvement effect of the sampled value compensation amount and the recentered PAM4 decision boundary on the compensated residual, an 800G multi-channel PAM4 receiving link simulation scenario was constructed. In the simulation scenario, multi-channel PAM4 receiving sampling data with the same compensated channel number, the same adjacent interference channel number, the same compensated channel PAM4 decision level identifier, and the same sampling phase position were selected. The PAM4 level center value was set in ascending order from the first PAM4 level identifier to the fourth PAM4 level identifier, and the invariant conditions were kept consistent, so that the simulation differences mainly came from the state change relationship of adjacent interference channels, the sampling delay position, the PAM4 level jump direction, and the receiving compensation cycle number.

[0103] During the simulation, the sampling deviation is calculated according to the sampling segments of the compensated channel at the same PAM4 level. The simulation distinguishes between the state of adjacent interfering channels maintaining the same level and the state of adjacent interfering channels switching PAM4 levels, forming a PAM4 switching response sampling record. The sampling deviation in the state of adjacent interfering channels maintaining the same level is taken as the state of maintaining the same level residual. The difference between the sampling deviation in the state of adjacent interfering channels switching PAM4 levels and the state of maintaining the same level residual is recorded as the switching residual. Forward switching residuals and reverse switching residuals are obtained under the same PAM4 level pair, thus forming a channel crosstalk response record. The state of maintaining the same level residual, forward switching residual, reverse switching residual, and channel crosstalk response are summarized according to different sampling delay positions to obtain... Figure 5 .

[0104] Figure 5In the graph, the horizontal axis represents the sampling delay position, and the vertical axis represents the voltage offset, in mV. Solid dots represent the same-level retention residual, dashed squares represent the positive transition residual, dotted-dash triangles represent the reverse transition residual, and dotted-line diamonds represent the channel crosstalk response. The same-level retention residual is used to represent the residual reference of the compensated channel sampling deviation when adjacent interfering channels have not undergone PAM4 level switching; the positive transition residual is used to represent the transition residual formed relative to the same-level retention residual when adjacent interfering channels are in a positive PAM4 level transition; the reverse transition residual is used to represent the transition residual formed relative to the same-level retention residual when adjacent interfering channels are in a reverse PAM4 level transition; and the channel crosstalk response is used to represent the directional voltage influence extracted from the difference between the positive and reverse transition residuals. Figure 5 It can be seen that the residual remains close to zero and remains flat when the same level is maintained. The residuals of the positive jump and the negative jump change in opposite directions at the same sampling delay position. The channel crosstalk response changes with the sampling delay position and is more obvious near the center sampling. This indicates that the present invention can separate the directional influence of the PAM4 level of adjacent interference channels on the jump from the residual reference in the same level maintenance state, so that the sampled value compensation amount has a clear source of channel crosstalk response.

[0105] Further, based on the channel crosstalk response record, a compensation amount for the sampled values ​​of the PAM4 level in the adjacent interfering channel under the jumping state is generated. When the average level on both sides of the PAM4 decision boundary has formed a compensation amount, a re-centered PAM4 decision boundary is formed according to the center value of the PAM4 level on both sides and the compensation amount of the sampled values ​​on both sides. When the level on either side of the PAM4 decision boundary has not formed a compensation amount, a PAM4 decision boundary retention value is formed. Subsequently, the equalized PAM4 sampled values ​​of the compensated channel are processed along the receiving compensation cycle number. The compensation amount of the sampled value is used to obtain the compensated PAM4 sampled values, and PAM4 decision is performed on the compensated PAM4 sampled values ​​according to the re-centered PAM4 decision boundary or the PAM4 decision boundary retention value, forming a compensated PAM4 decision record. The sampling deviation, the compensated residual, and the change of the re-centered PAM4 decision boundary are summarized according to the receiving compensation cycle number to obtain the PAM4 decision record. Figure 6 .

[0106] Figure 6In the graph, the horizontal axis represents the receive compensation cycle number, and the vertical axis represents the voltage offset, in mV. Solid dots represent sampling deviation, dashed squares represent the residual after compensation, and dotted triangles represent the change in the PAM4 decision boundary after recentering. Sampling deviation indicates the voltage offset of the PAM4 sampled value after equalization relative to the center value of the PAM4 level; the residual after compensation indicates the voltage offset remaining after the compensation amount and the recentered PAM4 decision boundary participate in the PAM4 decision; the change in the recentered PAM4 decision boundary indicates the adjustment range of the voltage position of the recentered PAM4 decision boundary relative to the retained value of the PAM4 decision boundary. Figure 6 It can be seen that the sampling deviation remains at a similar level in each receiving compensation cycle, indicating that the input sampling deviation does not experience significant additional disturbances. The residual after compensation decreases as the receiving compensation cycle number increases, and the change in the PAM4 decision boundary after recentering gradually adjusts and tends to level off as the receiving compensation cycle number increases. This indicates that after incorporating the residual after compensation into the PAM4 transition response sampling record of the next receiving compensation cycle, the present invention can update the channel crosstalk response record based on the direction relationship of the residual after compensation, so that the sample value compensation amount and the PAM4 decision boundary maintain a corresponding correction relationship, thereby reducing the influence of the PAM4 level of adjacent interference channels on the transition on the PAM4 decision result of the compensated channel.

[0107] This embodiment also provides a computer device applicable to the 800G PAM4 signal compensation method based on channel crosstalk characteristics, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the 800G PAM4 signal compensation method based on channel crosstalk characteristics as proposed in the above embodiment.

[0108] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0109] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements the 800G PAM4 signal compensation method based on channel crosstalk characteristics as proposed in the above embodiments. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0110] In summary, this invention achieves the separation of the channel crosstalk response from the transition states of the PAM4 level of adjacent interfering channels by pairwise processing of the same-level residual, transition residual, positive transition residual, and reverse transition residual, thus giving the sampled value compensation a clear directional source. By forming the recentered PAM4 decision boundary together with the sampled value compensation and the center values ​​of the PAM4 levels on both sides, the corresponding correction of the compensated PAM4 sampled value and the decision boundary is achieved, ensuring that the PAM4 decision process is consistent with the channel crosstalk response record.

[0111] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for 800G PAM4 signal compensation based on channel crosstalk characteristics, characterized in that, include: Collect multi-channel PAM4 received sampling data within the same receiving compensation period. According to the sampling segments identified by the same PAM4 level of the compensated channel, the difference between the equalized PAM4 sample value and the corresponding PAM4 level center value is recorded as the sampling deviation. Distinguish between the state of adjacent interference channels maintaining the same level and the state of PAM4 level switching, and form a PAM4 switching response sampling record. The sampling deviation of adjacent interference channels in the same level maintenance state in the PAM4 transition response sampling record is used as the same level maintenance residual. The difference between the sampling deviation of adjacent interference channels in the PAM4 level pair transition state and the same level maintenance residual is calculated to obtain the transition residual. The channel crosstalk response is extracted according to the difference between the positive transition residual and the negative transition residual of the same PAM4 level pair to form the channel crosstalk response record. Based on the channel crosstalk response record, the sample value compensation amount of the PAM4 level of the adjacent interference channel under the jumping state is generated. When the sample value compensation amount has been formed on both sides of the PAM4 decision boundary, the recentered PAM4 decision boundary is calculated with the center value of the PAM4 level on both sides and the sample value compensation amount on both sides. When the sample value compensation amount has not been formed on either side of the PAM4 decision boundary, the PAM4 decision boundary retention value is formed, and the PAM4 signal compensation parameter record is formed. The equalized PAM4 sample value of the compensated channel is corrected based on the sample value compensation amount in the PAM4 signal compensation parameter record to obtain the compensated PAM4 sample value. PAM4 decision is performed on the compensated PAM4 sample value according to the recentered PAM4 decision boundary or the PAM4 decision boundary retention value to form a compensated PAM4 decision record. The difference between the compensated PAM4 sample value and the center value of the PAM4 level to which the compensated PAM4 decision level identifier belongs is recorded as the compensated residual. The compensated residual is incorporated into the PAM4 transition response sampling record of the next receiving compensation cycle. The channel crosstalk response record is updated according to the direction relationship of the compensated transition residual under the positive PAM4 level transition and the reverse PAM4 level transition.

2. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 1, characterized in that, The multi-channel PAM4 received sampling data includes the compensated channel number, the adjacent interference channel number, the PAM4 symbol number, the discrete sampling number, the sampling phase position, the sampling delay position, the equalized PAM4 sample value, the PAM4 decision level identifier of the compensated channel, and the PAM4 level identifier of the adjacent interference channel.

3. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 2, characterized in that, The sampling segment identified by the same PAM4 level for the compensated channel is recorded as the sampling deviation by the difference between the equalized PAM4 sample value and the corresponding PAM4 level center value. The sampling deviation is further distinguished between adjacent interference channels maintaining the same level and PAM4 level transition states, forming a PAM4 transition response sampling record including: Based on the changing position of the PAM4 decision level indicator of the compensated channel, the sampling segments of the compensated channel with the same PAM4 level indicator are divided, and sampling segment numbers are generated. The equalized PAM4 sampled values ​​are grouped according to the PAM4 decision level identifier of the compensated channel to obtain the PAM4 level center value. The difference between the equalized PAM4 sampled value and the corresponding PAM4 level center value in the sampling segment of the compensated channel with the same PAM4 level identifier is recorded as the sampling deviation. Based on the change relationship of the PAM4 level identifier of adjacent interference channels on two adjacent PAM4 symbols, the state change relationship of adjacent interference channels is marked as either the adjacent interference channels maintaining the same level or the adjacent interference channels PAM4 level pair switching state. In the adjacent interference channels maintaining the same level, the same maintaining PAM4 level identifier is formed. In the adjacent interference channels PAM4 level pair switching state, the PAM4 level identifier before the switching, the PAM4 level identifier after the switching, the PAM4 level pair, and the PAM4 switching direction are formed. The sampling segment number, sampling deviation, relationship of adjacent interference channel status changes, same hold PAM4 level identifier, PAM4 level pair, PAM4 level identifier before the transition, PAM4 level identifier after the transition, and PAM4 transition direction are organized to form a PAM4 transition response sampling record.

4. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 3, characterized in that, The calculation of the difference between the sampling deviation of the PAM4 level of adjacent interference channels under the jumping state and the residual of maintaining the same level, to obtain the jumping residual includes: PAM4 transition response sampling records that have the same receiving compensation cycle number, compensated channel number, adjacent interference channel number, compensated channel PAM4 decision level identifier, sampling phase position, and sampling delay position are classified into the same type of sampling record. Within the same type of sampling record, the sampling deviations of adjacent interference channels under the same level holding state are divided according to the same PAM4 level identifier. The single sampling deviation after division or the middle voltage position after sorting by voltage value is taken as the same level holding residual. Within the same type of sampling record, the sampling deviation of adjacent interference channels under the PAM4 level pair transition state is divided according to the PAM4 level pair and the PAM4 transition direction. The single sampling deviation after division or the middle voltage position after sorting by voltage value is taken as the sampling deviation of the transition state. Using the same level holding residual under the same holding PAM4 level identifier to which the PAM4 level identifier belongs before the jump as the residual reference, the difference between the jump state sampling deviation and the same level holding residual is recorded as the jump residual; when no same level holding residual corresponding to the PAM4 level identifier before the jump is formed, the jump residual of the corresponding jump state sampling deviation is not calculated.

5. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 4, characterized in that, The process of extracting the channel crosstalk response based on the difference between the forward transition residual and the reverse transition residual of the same PAM4 level pair, and forming the channel crosstalk response record, includes: Under the same type of sampling record and the same PAM4 level pair, the transition residual is divided based on the high / low relationship between the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition and the center value of the PAM4 level to which the PAM4 level identifier belongs after the transition. When the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition is lower than the center value of the PAM4 level to which the PAM4 level identifier belongs after the transition, the corresponding transition residual is recorded as a positive transition residual. When the center value of the PAM4 level to which the PAM4 level identifier belongs before the transition is higher than the center value of the PAM4 level to which the PAM4 level identifier belongs after the transition, the corresponding transition residual is recorded as a negative transition residual. When both positive transition residual and negative transition residual exist simultaneously under the same type of sampling record and the same PAM4 level, the positive transition residual is used as the comparison quantity, and the negative transition residual is used as the comparison benchmark. Half of the difference between the positive transition residual and the negative transition residual is recorded as the channel crosstalk response. According to the received compensation cycle number, the compensated channel number, the adjacent interference channel number, the PAM4 decision level identifier of the compensated channel, the sampling phase position, the sampling delay position, the PAM4 level pair and the PAM4 transition direction, the same level holding residual, the positive transition residual, the negative transition residual and the channel crosstalk response are written into the channel crosstalk response record.

6. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 4 or 5, characterized in that, The PAM4 signal compensation parameter record includes: According to the received compensation cycle number, the compensated channel number, the adjacent interference channel number, the PAM4 decision level identifier of the compensated channel, the sampling phase position, the sampling delay position, the PAM4 level pair, and the PAM4 transition direction, the channel crosstalk response is retrieved from the channel crosstalk response record; when the PAM4 transition direction is a positive PAM4 level pair transition, the sign of the channel crosstalk response is inverted and used as the sampled value compensation amount; when the PAM4 transition direction is a negative PAM4 level pair transition, the channel crosstalk response is used as the sampled value compensation amount. According to the arrangement order of PAM4 level center values ​​from low to high, the intermediate voltage position between the PAM4 level center values ​​of two adjacent compensated channels is recorded as the PAM4 decision boundary, and the compensated channels on both sides of the PAM4 decision boundary are recorded as the low-side PAM4 level mark and the high-side PAM4 level mark, respectively. When both the low-side PAM4 level marker and the high-side PAM4 level marker have formed sampled value compensation amounts, the center value of the PAM4 level to which the low-side PAM4 level marker belongs is added to the sampled value compensation amount under the low-side PAM4 level marker to obtain the low-side compensation center position. The center value of the PAM4 level to which the high-side PAM4 level marker belongs is added to the sampled value compensation amount under the high-side PAM4 level marker to obtain the high-side compensation center position. When the low-side compensation center position is lower than the high-side compensation center position, the intermediate voltage position between the low-side compensation center position and the high-side compensation center position is recorded as the PAM4 decision boundary after recentering. When the low-side PAM4 level indicator or the high-side PAM4 level indicator does not form a sample value compensation amount, or when the low-side compensation center position is not lower than the high-side compensation center position, the intermediate voltage position between the PAM4 level center value to which the low-side PAM4 level indicator belongs and the PAM4 level center value to which the high-side PAM4 level indicator belongs is recorded as the PAM4 decision boundary retention value. Write the sampled value compensation amount, low-side PAM4 level identifier, high-side PAM4 level identifier, and PAM4 decision boundary or PAM4 decision boundary retention value after recentering into the PAM4 signal compensation parameter record.

7. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 6, characterized in that, The PAM4 decision record after compensation includes: The equalized PAM4 sampled value of the compensated channel is processed along the PAM4 symbol sequence. When the state change relationship of the adjacent interference channel in the record to which the equalized PAM4 sampled value belongs is a transition state of the PAM4 level of the adjacent interference channel and the sampled value compensation amount and the recentered PAM4 decision boundary are found in the PAM4 signal compensation parameter record, the equalized PAM4 sampled value is added to the sampled value compensation amount to obtain the compensated PAM4 sampled value. When the sampled value compensation amount is not found, or the state change relationship of the adjacent interference channel is a state of maintaining the same level of the adjacent interference channel, or the PAM4 decision boundary retention value is recorded in the PAM4 signal compensation parameter record, the equalized PAM4 sampled value is used as the compensated PAM4 sampled value. When the state change relationship of the adjacent interference channel corresponding to the compensated PAM4 sample value is a transition state of the PAM4 level of the adjacent interference channel, the re-centered PAM4 decision boundary or the PAM4 decision boundary retention value is retrieved from the PAM4 signal compensation parameter record as the current decision boundary between two adjacent PAM4 level identifiers; when the state change relationship of the adjacent interference channel corresponding to the compensated PAM4 sample value is a state of maintaining the same level of the adjacent interference channel, the current decision boundary is formed based on the center value of the PAM4 level to which the two adjacent PAM4 level identifiers belong; the compensated PAM4 sample value is compared with each current decision boundary to obtain the compensated PAM4 decision level identifier. The difference between the compensated PAM4 sample value and the center value of the PAM4 level to which the compensated PAM4 decision level identifier belongs is recorded as the compensated residual. The equalized PAM4 sample value, the sample value compensation amount, the compensated PAM4 sample value, the current decision boundary, the compensated PAM4 decision level identifier, and the compensated residual are written into the compensated PAM4 decision record.

8. The 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in claim 5 or 7, characterized in that, The update channel crosstalk response record includes: Based on the compensated PAM4 decision record, when forming the PAM4 transition response sampling record in the next receiving compensation cycle, the compensated residual is incorporated into the PAM4 transition response sampling record under the same sampling conditions in the next receiving compensation cycle according to the compensated channel number, adjacent interference channel number, compensated PAM4 decision level identifier, sampling phase position, sampling delay position and adjacent interference channel state change relationship. In the PAM4 transition response sampling records after integration, when the state change relationship between adjacent interference channels is that the adjacent interference channels maintain the same level, the compensated residuals are aggregated according to the same PAM4 level identifier to obtain the compensated same-level maintenance residual; when the state change relationship between adjacent interference channels is that the PAM4 level pair transitions between adjacent interference channels, the compensated residuals are aggregated according to the PAM4 level pair and the PAM4 transition direction to obtain the compensated transition state residual; taking the compensated same-level maintenance residual to which the PAM4 level identifier before the transition belongs as the residual reference, the difference between the compensated transition state residual and the compensated same-level maintenance residual is recorded as the compensated transition residual; The condition that the compensated channel number, adjacent interference channel number, compensated PAM4 decision level identifier, sampling phase position, sampling delay position, and PAM4 level pair are all the same is recorded as the same post-compensation residual comparison condition. Under the same post-compensation residual comparison condition, when the post-compensation transition residual under the positive PAM4 level pair transition and the post-compensation transition residual under the negative PAM4 level pair transition exist simultaneously and are in opposite directions, half of the difference between the two is recorded as the channel crosstalk response margin. The original channel crosstalk response in the channel crosstalk response record is added to the channel crosstalk response margin to obtain the updated channel crosstalk response. Otherwise, the original channel crosstalk response in the channel crosstalk response record is retained. The updated channel crosstalk response or the original channel crosstalk response is written into the channel crosstalk response record.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the 800G PAM4 signal compensation method based on channel crosstalk characteristics as described in any one of claims 1 to 8.

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