A method and apparatus for crosstalk cancellation in multi-channel data transmission based on digital encoding

Abstract

The application discloses a kind of based on digital encoding multi-channel data transmission crosstalk elimination method and device, the application based on digital encoding multi-channel data transmission crosstalk elimination method includes that each three-way signal is converted to four-way signal for each channel needing sending multiple parallel signals of sending party to crosstalk elimination, and the multiple signals obtained after conversion are combined and sent into channel to carry out data transmission;For the signal received by each channel, each four-way signal is restored to three-way signal to obtain original data;The device of the application includes the encoder for converting the three-way signal needing sending of sending party to four-way signal and the decoder for restoring the four-way signal received by receiving party to three-way signal.The application aims at the data transmission of multi-channel digital signal to ensure efficient premise and realize maximum crosstalk elimination.

Description

Technical Field

[0001] The present invention relates to the technical field of high-speed circuit design, and in particular to a method and device for eliminating crosstalk in multi-channel data transmission based on digital coding. Background Art

[0002] In recent years, the growing demand for data and data-centric computing has driven the need for high-speed, high-precision data center interconnects, leading to stricter linearity and noise requirements. As chip sizes shrink and data transmission speeds increase, signal integrity has become an inevitable issue in high-speed circuit design, and crosstalk is a significant part of this issue.

[0003] Crosstalk is primarily caused by electromagnetic field coupling. When a rapidly changing signal (such as a rising or falling edge) on one signal line generates an electromagnetic field, this field can couple to adjacent signal lines, generating interference signals. In high-speed circuit design, signal lines are treated as transmission lines, and factors such as their characteristic impedance, terminal matching, and wavelength all affect the degree of crosstalk.

[0004] The necessity of solving the crosstalk problem is also reflected in the following points. Ensuring signal integrity: Preventing the introduction of additional noise, which causes signal distortion and affects the accurate transmission of data, may increase the bit error rate and reduce system stability; Improving system reliability: In application fields such as communications, data centers, and high-performance computing, the system needs to be highly reliable; Meeting timing requirements: High-speed signals have strict timing requirements. Crosstalk may cause signal delays or advances, affecting the alignment of clock and data edges, and thus violating timing constraints, affecting system clock frequency and data transmission rate; Adapting to high-density design requirements: With technological advancements, electronic devices are becoming increasingly miniaturized, and PCB board design density is increasing. This has reduced the spacing between signal lines and increased the possibility of crosstalk. Solving the crosstalk problem helps maintain good signal quality in high-density designs.

[0005] Current design strategies and techniques include, but are not limited to, increasing trace spacing, employing differential pair signaling, using shielding, adding ground isolation strips, optimizing routing topologies, and implementing appropriate termination techniques. Specifically, one type of solution utilizes board-level engineering methods to explore the issue of coupling noise reduction and propose performance metrics that designers can use to determine the most appropriate interconnect configuration: shielding, buffering, or spacing. Another type of solution utilizes differential traces, which effectively reduces crosstalk but requires doubling the number of redundant traces, significantly reducing trace efficiency.

[0006] Another low-crosstalk and relatively low-cost solution is bus coding. Commonly used codes include the FC family of codes (FC), bit-reversal codes (BI), no-adjacent-transition codes (NATs), transition-mode classification codes, SDT-free codes that account for inductance effects, and JCI codes. However, these codes require the addition of redundant wires, which reduces line efficiency and increases area. Minimizing crosstalk while maintaining a certain line efficiency is a difficult balancing act. These codes, such as no-adjacent-transition codes (NATs), transition-mode classification codes, SDT-free codes that account for inductance effects, and JCI codes, require the addition of redundant wires, which reduces line efficiency and increases area. Minimizing crosstalk while maintaining a certain line efficiency is a difficult balancing act. Summary of the Invention

[0007] The technical problem to be solved by the present invention is as follows: In response to the above-mentioned problems of the prior art, a method and device for eliminating crosstalk in multi-channel data transmission based on digital coding are provided. The present invention aims to achieve maximum crosstalk elimination while ensuring high efficiency in the data transmission of multi-channel digital signals, solve the crosstalk problem caused by electromagnetic coupling in high-speed data transmission, and prevent the introduction of additional noise from causing signal distortion and affecting the accurate transmission of data.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0009] A method for eliminating crosstalk in multi-channel data transmission based on digital coding, comprising the following steps:

[0010] S101: The transmitter converts three parallel signals to four signals for each channel to eliminate crosstalk, combines the converted signals, and sends them to the channel for data transmission.

[0011] S102: The receiving party restores each of the four channels of signals received by each channel into three channels of signals to obtain original data.

[0012] Optionally, in step S101, converting each three signals into four signals to eliminate crosstalk includes: if the three signals are 000, converting them into 0000; if the three signals are 001, converting them into 0001; if the three signals are 010, converting them into 0011; if the three signals are 011, converting them into 0110; if the three signals are 100, converting them into 0111; if the three signals are 101, converting them into 1000; if the three signals are 110, converting them into 1110; if the three signals are 111, converting them into 1111; in step S102, restoring each four signals into three signals is the reverse conversion process of converting each three signals into four signals.

[0013] Optionally, before step S101 , the process further includes reducing the speed of the original signal of each channel to obtain the signal of each channel.

[0014] Optionally, the speed reduction of the original multi-channel signals refers to speed reduction of the original signals of the three channels by demultiplexing to obtain twelve signals; when step S101 converts every three signals in the signals of each channel into four signals to eliminate crosstalk, a total of sixteen signals are obtained by converting the twelve signals of each channel, and step S102 combines the multi-channel signals obtained after the conversion and sends them into the channel for data transmission, which means combining the sixteen signals obtained after the conversion into four signals and sending them into the channel for data transmission.

[0015] Optionally, the original signals of the three channels are signals with a bandwidth of 20G, the twelve signals obtained by speed reduction are signals with a bandwidth of 5G, and the four signals obtained by combining are signals with a bandwidth of 20G.

[0016] In addition, the present invention also provides a multi-channel data transmission device for applying the multi-channel data transmission crosstalk elimination method based on digital coding, including an encoder for converting the three-way signal to be sent by the sender into a four-way signal and a decoder for restoring the four-way signal received by the receiver into a three-way signal.

[0017] Optionally, the logical expressions of the encoders are:

[0018] ,

[0019] ,

[0020] ,

[0021] ,

[0022] In the above formula, ~ They are the four converted signals, ~ They are three input signals, ~ They are ~ The inverted signal, is the XOR operation, is an AND operation; the logical expression of the decoder is:

[0023] ,

[0024] ,

[0025] ,

[0026] In the above formula, ~ They are the three restored signals, ~ The four signals received by the receiver are: ~ It is the inverted signal of the four signals received by the receiver.

[0027] Optionally, the sender includes an encoder and a 4:1 multiplexer. The sender encodes the 12 parallel signals to be sent into 16 parallel signals through three encoders and multiplexes them into 4 parallel signals through a 4:1 multiplexer, and finally sends them to the receiver through four channels; the receiver includes a 1:4 demultiplexer and a decoder. The 1:4 demultiplexer is used to demultiplex the 4 parallel signals to obtain 16 parallel signals, and to restore the 16 parallel signals to 12 parallel signals through four decoders.

[0028] Optionally, the input end of the encoder is further connected to a 1:4 demultiplexer for reducing the speed of the original signals of the three channels to obtain 12 parallel signals to be transmitted.

[0029] In addition, the present invention also provides a method for calculating the crosstalk cancellation effect of the multi-channel data transmission crosstalk cancellation method based on digital coding, comprising the following steps:

[0030] S101, represents the coupling capacitance between adjacent conductors, represents the load capacitance of the driver, thereby determining any The crosstalk level of the conductors is:

[0031] ,

[0032] In the above formula, For any The crosstalk level of the wires, is the intermediate variable, is a constant determined by the driver strength and the wire resistance, is the signal swing, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor;

[0033] S102, calculating the parallel transmission mode of the three-way signal before the crosstalk cancellation, for any of the three-way signal Calculate the crosstalk degree of the three-way signal when it is converted from any value to other different values ​​using a wire , and calculate all crosstalk levels The average value of the crosstalk level before the crosstalk elimination is obtained under the three-way parallel transmission mode; the average crosstalk level of the four-way parallel transmission mode after the crosstalk elimination is calculated for any of the four-way signals. Calculate the crosstalk degree of the four-way signal when it is converted from any value to other different values ​​using a wire , and calculate all crosstalk levels The average value of the crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is obtained; the average crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is subtracted from the average crosstalk degree under the three-way parallel transmission mode before the crosstalk elimination, to obtain the crosstalk elimination effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

[0034] Optionally, step S101 further includes determining any Delay of the wire for:

[0035] ,

[0036] In the above formula, is a constant determined by the driver strength and the wire resistance, For the The voltage on the wire, For the The voltage on the wire, For the The voltage on the root wire; Step S102 also includes calculating the three-way signal parallel transmission mode before the crosstalk elimination, for any of the three signals Calculate the delay of converting any value of the three signals to other different values ​​using a wire , and calculate all delays The average value of the three-way signal parallel transmission method before crosstalk elimination is used to obtain the average delay; the four-way signal parallel transmission method after crosstalk elimination is used to calculate the average delay of any of the four signals. Calculate the delay of converting any value of the four signals to other different values ​​using a wire , and calculate all delays The average value of the average delay in the four-way signal parallel transmission mode after crosstalk elimination is obtained; the average delay in the four-way signal parallel transmission mode after crosstalk elimination is subtracted from the average delay in the three-way signal parallel transmission mode before crosstalk elimination to obtain the delay optimization effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

[0037] Compared with the prior art, the present invention mainly has the following advantages:

[0038] 1. Minimizing crosstalk under a certain online efficiency is an issue that requires a balanced approach. In order to solve the crosstalk problem caused by electromagnetic coupling in high-speed data transmission and prevent the introduction of additional noise from causing signal distortion and affecting the accurate transmission of data, the present invention proposes a new digital-based encoding mechanism, including converting every three signals of each channel into four signals to eliminate crosstalk, combining the multi-channel signals obtained after the conversion and sending them into the channel for data transmission. Minimizing crosstalk under a certain online efficiency is an issue that requires a balanced approach. At the same time, the present invention can achieve maximum crosstalk elimination under the premise of a certain online efficiency, is widely applicable, does not require other parameter calculations and adjustments during system operation, is easy to process, and introduces less overhead.

[0039] 2. The present invention can be applied to fields such as communications, data centers, and high-performance computing to improve sufficient system reliability and maintain good signal quality in high-density designs. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of the basic process of the method of the embodiment of the present invention.

[0041] Figure 2 This is the coding logic relationship for converting three-way signals into four-way signals in an embodiment of the present invention.

[0042] Figure 3 Schematic diagram of the circuit principle of the encoder in the embodiment of the present invention, wherein (a) to (d) are the first to fourth signals obtained by conversion respectively. ~ encoding circuit.

[0043] Figure 4 Schematic diagram of the circuit principle of the decoder in the embodiment of the present invention, wherein (a) to (c) are the first to third restored signals respectively. ~ decoding circuit.

[0044] Figure 5Schematic diagram of the structure of a multi-channel data transmission device and its comparative solution in an embodiment of the present invention, wherein (a) is a comparative solution without an encoder and a decoder, and (b) is a multi-channel data transmission device.

[0045] Figure 6 Schematic diagram of the structure of the channel used in the embodiment of the present invention.

[0046] Figure 7 Schematic diagram of the insertion loss and far-end crosstalk of the channel used in the embodiment of the present invention.

[0047] Figure 8 1 is a comparison of signal eye diagrams when an encoder is not used and when an encoder is used in an embodiment of the present invention, where (a) is a signal eye diagram when an encoder is not used, and (b) is a signal eye diagram when an encoder is used. DETAILED DESCRIPTION

[0048] like Figure 1 As shown, the method for eliminating crosstalk in multi-channel data transmission based on digital coding in this embodiment includes the following steps:

[0049] S101: The transmitter converts three parallel signals to four signals for each channel to eliminate crosstalk, combines the converted signals, and sends them to the channel for data transmission.

[0050] S102: The receiving party restores each of the four channels of signals received by each channel into three channels of signals to obtain original data.

[0051] It should be noted that there may be multiple encoding methods for converting each three signals into four signals, but the crosstalk elimination effects under different encoding methods are different. As an optional implementation method, in step S101 of this embodiment, converting each three signals into four signals for crosstalk elimination includes: if the three signals are 000, converting them into 0000; if the three signals are 001, converting them into 0001; if the three signals are 010, converting them into 0011; if the three signals are 011, converting them into 0110; if the three signals are 100, converting them into 0111; if the three signals are 101, converting them into 1000; if the three signals are 110, converting them into 1110; if the three signals are 111, converting them into 1111. The above conversion relationships are specifically shown in Table 1.

[0052] Table 1 Coding design

[0053]

[0054] Restoring each of the four signals into three signals in step S102 is the reverse conversion process of converting each of the three signals into four signals. The restoration rules can be obtained by querying Table 1, which will not be described in detail here.

[0055] This embodiment proposes the above-mentioned new digital-based encoding mechanism, which introduces an encoding module before the signal enters the channel. Through this encoding, three-bit data is converted into four-bit data, completely eliminating bit conversions such as 010-101, thereby minimizing crosstalk and being able to control the crosstalk between lines to half of the crosstalk amplitude when the encoding module is not introduced.

[0056] In this embodiment, before step S101, the original signal of each channel is further reduced in speed to obtain the signal of each channel. In this embodiment, reducing the speed of the original multi-channel signal means reducing the speed of the original signals of three channels by demultiplexing to obtain twelve signals; when step S101 converts every three signals in the signals of each channel into four signals to eliminate crosstalk, a total of sixteen signals are obtained from the twelve signals of each channel; and in step S102, combining the converted multi-channel signals and sending them to the channel for data transmission means combining the converted sixteen signals into four signals and sending them to the channel for data transmission.

[0057] In this embodiment, the original signals of the three channels are signals with a bandwidth of 20G, the twelve signals obtained by speed reduction are signals with a bandwidth of 5G, and the four signals obtained by combining are signals with a bandwidth of 20G.

[0058] Based on the coding design in Table 1, assume that the input is: S=<s0,s1,s2> , output: D=<d0,d1,d2,d3> , we can analyze the encoding logic relationship of converting three-way signals into four-way signals as follows Figure 2 As shown, ~ They are the four converted signals, ~ The three input signals (digital signals) are respectively input, and the signal values ​​are 0 or 1. On this basis, this embodiment also provides a multi-channel data transmission device for applying the multi-channel data transmission crosstalk elimination method based on digital coding, including an encoder for converting the three-channel signals to be sent by the sender into a four-channel signal and a decoder for restoring the four-channel signals received by the receiver into a three-channel signal.

[0059] The encoding circuit of the encoder in this embodiment is as follows Figure 3 As shown in (a) to (d), (a) to (d) are the first to fourth signals obtained by conversion. ~ The encoding circuits have logical expressions as follows:

[0060] ,

[0061] ,

[0062] ,

[0063] ,

[0064] In the above formula, ~ They are the four converted signals, ~ They are three input signals, ~ They are ~ The inverted signal, is the XOR operation, The above encoding structure can realize the conversion of multi-channel three-bit to four-bit data. The converted data will generate less crosstalk when transmitted in the channel. To obtain the original data information, it is only necessary to add a decoding module after the channel. It can also be extended to more channels. It can be seen that the device of this embodiment can achieve the maximum degree of crosstalk elimination when the online efficiency is certain. It is widely applicable, does not require other parameter calculations and adjustments during system operation, is easy to process, and introduces low overhead.

[0065] Figure 4 The schematic diagram of the circuit principle of the decoder in this embodiment, where (a) to (c) are the first to third restored signals respectively. ~ The decoding circuits have logical expressions as follows:

[0066] ,

[0067] ,

[0068] ,

[0069] In the above formula, ~ They are the three restored signals, ~ The four signals received by the receiver are: ~ It is the inverted signal of the four signals received by the receiver.

[0070] like Figure 5As shown in (b), the transmitter of the multi-channel data transmission device in this embodiment includes an encoder and a 4:1 multiplexer. The transmitter encodes the 12 parallel signals to be sent into 16 parallel signals through three encoders and multiplexes them into 4 parallel signals through a 4:1 multiplexer, and finally sends them to the receiver through four channels; the receiver includes a 1:4 demultiplexer and a decoder. The 1:4 demultiplexer is used to demultiplex the 4 parallel signals into 16 parallel signals, and then restore the 16 parallel signals into 12 parallel signals through four decoders. Figure 5 (a) is a schematic diagram of the comparative scheme structure without encoder and decoder. Since the decoder and encoder involve the change in the number of signal channels, Figure 5 The number of channels in the middle part between the decoder and encoder is different in (a) and (b).

[0071] As an optional implementation, a 1:4 demultiplexer ( Figure 5 Not shown in the figure), which is used to reduce the speed of the original signals of the three channels to obtain 12 parallel signals that need to be sent.

[0072] Figure 5 The signal generator is used as a data source to generate the original signal of each channel. In this embodiment, a pseudo-random signal generator (PRBS generator) is used. In actual application, a real data source is used. Figure 5 (a) shows a comparison scheme without an encoder. In this comparison scheme, the demultiplexer demultiplexes the original signals of the three channels and reduces the speed to obtain twelve signals. Then, the twelve signals are directly combined into three signals through a 4:1 multiplexer. Figure 5 (a) and Figure 5 (b) A signal in the two circuit models 、 The quality of the encoder is used to observe the effect of the encoder. The structure of the channels (channel 0 to channel 9) used in the experiment of this embodiment is as follows Figure 6 As shown in the figure, interference lines 1 to 3 respectively cause insertion loss (IL) and far-end crosstalk (FEXT 1 to FEXT 3) to the victim line. The insertion loss (IL) and far-end crosstalk (XT) obtained by the test are shown in the figure. Figure 7 As shown in the figure, the channel used in the test is a channel with crosstalk level 0. The signal eye diagram obtained by transient simulation of the PRBS signal generated by the PRBS generator is as follows: Figure 8 As shown, Figure 8 (a) is the signal eye diagram without coding. Figure 8 (b) shows the eye diagram of the signal after encoding. It can be seen that Figure 5(b) relative to Figure 5 As for (a) in the figure, the signal quality is significantly improved after adding the encoder.

[0073] For parallel links, if represents the coupling capacitance between adjacent conductors, is the load capacitance of the driver, then any Delay of the wire It can be expressed as:

[0074] ,

[0075] in is a constant determined by the driver strength and the wire resistance, It is the first The voltage change on the wire. The relative voltage change of the adjacent wires constitutes the crosstalk part of the wire delay. For the convenience of discussion, the coupling effect between non-directly adjacent wires (such as the first Root and In this case, according to the definition of crosstalk, the first The crosstalk level of the conductor is:

[0076] ,

[0077] in , ( is the signal swing), Indicates the transmission Normalized voltage change on each wire. Assume that data transitioning from 0 to 1 is represented as +, data transitioning from 1 to 0 is represented as -, and data remaining unchanged is represented as o. Consider the case of data transitioning from 010 to 101. Without encoding, the resulting data is converted to +-+. According to the above calculation formula, the normalized crosstalk level is D|(-1-1)+(-1-1)|=4D. With encoding, 010 is encoded as 0011, and 101 is encoded as 1000. The data transmitted through the channel is converted to +o--, resulting in a crosstalk level of D|(0-1)+[0-(-1)]|=0D. Therefore, encoding significantly reduces crosstalk. All crosstalk scenarios before and after encoding are shown in Tables 2 and 3.

[0078] Table 2 All cases of crosstalk before encoding

[0079]

[0080] Figure 2In the data transmission, the case where 010 jumps to 101 is the case with the largest crosstalk (crosstalk degree = 4D), and it is possible for any 3 bits to jump to another 3 bits during data transmission.

[0081] Table 3 All cases of crosstalk after encoding

[0082]

[0083] When there are four lines, the two middle lines experience crosstalk, so each transition has two columns. For example, when 010 is encoded as 0011 and 101 is encoded as 1000, the crosstalk received by the two middle victim lines is shown in Tables 2 and 3. The high crosstalk levels of 3D and 4D before encoding are completely eliminated after encoding.

[0084] In addition, this embodiment further provides a method for calculating the crosstalk cancellation effect of the aforementioned multi-channel data transmission crosstalk cancellation method based on digital coding, comprising the following steps:

[0085] S101, represents the coupling capacitance between adjacent conductors, represents the load capacitance of the driver, thereby determining any The crosstalk level of the conductors is:

[0086] ,

[0087] In the above formula, For any The crosstalk level of the wires, is the intermediate variable, is a constant determined by the driver strength and the wire resistance, is the signal swing, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor;

[0088] S102, calculating the parallel transmission mode of the three-way signal before the crosstalk cancellation, for any of the three-way signal Calculate the crosstalk degree of the three-way signal when it is converted from any value to other different values ​​using a wire , as shown in Table 2, and calculate all crosstalk levels The average value of the crosstalk level before the crosstalk elimination is obtained under the three-way parallel transmission mode; the average crosstalk level of the four-way parallel transmission mode after the crosstalk elimination is calculated for any of the four-way signals. Calculate the crosstalk degree of the four-way signal when it is converted from any value to other different values ​​using a wire , as shown in Table 3, and calculate all crosstalk levels The average value of the crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is obtained; the average crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is subtracted from the average crosstalk degree under the three-way parallel transmission mode before the crosstalk elimination, to obtain the crosstalk elimination effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

[0089] In addition, step S101 of this embodiment also includes determining any Delay of the wire for:

[0090] ,

[0091] In the above formula, is a constant determined by the driver strength and the wire resistance, For the The voltage on the wire, For the The voltage on the wire, For the The voltage on the root wire; Step S102 also includes calculating the three-way signal parallel transmission mode before the crosstalk elimination, for any of the three signals Calculate the delay of converting any value of the three signals to other different values ​​using a wire , and calculate all delays The average value of the three-way signal parallel transmission method before crosstalk elimination is used to obtain the average delay; the four-way signal parallel transmission method after crosstalk elimination is used to calculate the average delay of any of the four signals. Calculate the delay of converting any value of the four signals to other different values ​​using a wire , and calculate all delays The average value of the average delay in the four-way signal parallel transmission mode after crosstalk elimination is obtained; the average delay in the four-way signal parallel transmission mode after crosstalk elimination is subtracted from the average delay in the three-way signal parallel transmission mode before crosstalk elimination to obtain the delay optimization effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

[0092] In summary, this embodiment discloses a digital coding technology for eliminating crosstalk in multi-channel data transmission, including introducing coding before the data enters the channel, and reducing the bit conversion from 010 to 101 to the greatest extent through coding, thereby controlling the crosstalk between lines to half of the crosstalk amplitude when the coding module is not introduced. In terms of the overall implementation framework, in this embodiment, the three high-speed signals are first slowed down by a demultiplexer, and then enter the encoder for encoding processing. The encoded low-speed signals are then combined into four channels by a multiplexer and then enter the channel for data transmission. Compared with the Fibonacci coding that has been proven to be effective, the coding used in this embodiment can reduce the average crosstalk level per wire by about 6.7%. This embodiment can achieve maximum crosstalk elimination under the premise of a certain online efficiency, is widely applicable, does not require other parameter calculations and adjustments during system operation, is easy to process, and introduces less overhead. Compared with the currently available coding technologies, it can achieve better crosstalk elimination effects under a certain online efficiency.

[0093] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for eliminating crosstalk in multi-channel data transmission based on digital coding, characterized in that: The steps include: S101: The transmitter converts three parallel signals to four signals for each channel to eliminate crosstalk, combines the converted signals, and sends them to the channel for data transmission. S102, the receiving party restores each of the four channels of signals received by each channel into three channels of signals to obtain the original data; Before step S101, the process further includes reducing the speed of the original signals of each channel to obtain the signals of each channel, wherein reducing the speed of the original signals of each channel refers to reducing the speed of the original signals of the three channels by demultiplexing to obtain twelve channels of signals; When every three signals are converted into four signals to eliminate crosstalk in step S101, the multi-channel signals obtained after the conversion are sixteen signals. In step S102, the multi-channel signals obtained after the conversion are combined and sent to the channel for data transmission, which is to combine the sixteen signals obtained after the conversion into four signals and send them to the channel for data transmission.

2. The method for eliminating crosstalk in multi-channel data transmission based on digital coding according to claim 1, characterized in that: In step S101, converting each three signals into four signals to eliminate crosstalk includes: if the three signals are 000, converting them into 0000; if the three signals are 001, converting them into 0001; if the three signals are 010, converting them into 0011; if the three signals are 011, converting them into 0110; if the three signals are 100, converting them into 0111; if the three signals are 101, converting them into 1000; if the three signals are 110, converting them into 1110; if the three signals are 111, converting them into 1111; in step S102, restoring each four signals into three signals is the reverse conversion process of converting each three signals into four signals.

3. The method for eliminating crosstalk in multi-channel data transmission based on digital coding according to claim 1, characterized in that: The original signals of the three channels are signals with a bandwidth of 20G, the twelve signals obtained by speed reduction are signals with a bandwidth of 5G, and the four signals obtained by combining are signals with a bandwidth of 20G.

4. A multi-channel data transmission device for applying the multi-channel data transmission crosstalk elimination method based on digital coding according to any one of claims 1 to 3, characterized in that: The invention comprises an encoder for converting three-way signals to be sent by a transmitter into four-way signals and a decoder for restoring the four-way signals received by a receiver into three-way signals.

5. The multi-channel data transmission device according to claim 4, characterized in that: The logical expression of the encoder is: ， ， ， ， In the above formula, ~ They are the four converted signals, ~ They are three input signals, ~ They are ~ The inverted signal, is the XOR operation, is an AND operation; the logical expression of the decoder is: ， ， ， In the above formula, ~ They are the three restored signals, ~ The four signals received by the receiver are: ~ It is the inverted signal of the four signals received by the receiver.

6. The multi-channel data transmission device according to claim 4, characterized in that: The sender includes an encoder and a 4:1 multiplexer. The sender encodes the 12 parallel signals to be sent into 16 parallel signals through three encoders, multiplexes them into 4 parallel signals through a 4:1 multiplexer, and finally sends them to the receiver through four channels; the receiver includes a 1:4 demultiplexer and a decoder. The 1:4 demultiplexer is used to demultiplex the 4 parallel signals to obtain 16 parallel signals, and restore the 16 parallel signals to 12 parallel signals through four decoders. The input end of the encoder is also connected to a 1:4 demultiplexer to reduce the speed of the original signals of the three channels to obtain the 12 parallel signals to be sent.

7. A method for calculating the crosstalk cancellation effect used in the method for eliminating crosstalk in multi-channel data transmission based on digital coding according to any one of claims 1 to 3, characterized in that: The steps include: S201, represents the coupling capacitance between adjacent conductors, represents the load capacitance of the driver, thereby determining any The crosstalk level of the conductors is: ， In the above formula, For any The crosstalk level of the wires, is an intermediate variable, is a constant determined by the driver strength and the wire resistance, is the signal swing, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor, Indicates the transmission Normalized voltage change on the conductor; S202, calculating the parallel transmission mode of the three-way signal before the crosstalk cancellation, for any of the three-way signal Calculate the crosstalk degree of the three-way signal when it is converted from any value to other different values ​​using a wire , and calculate all crosstalk levels The average value of the three-way signal parallel transmission method before crosstalk elimination is used to obtain the average crosstalk level; After calculating the crosstalk elimination, in the four-way signal parallel transmission mode, for any of the four-way signals Calculate the crosstalk degree of the four-way signal when it is converted from any value to other different values ​​using a wire , and calculate all crosstalk levels The average value of the crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is obtained; the average crosstalk degree under the four-way parallel transmission mode after the crosstalk elimination is subtracted from the average crosstalk degree under the three-way parallel transmission mode before the crosstalk elimination, to obtain the crosstalk elimination effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

8. The crosstalk cancellation effect calculation method according to claim 7, wherein: Step S201 also includes determining any Delay of the wire for: ， In the above formula, is a constant determined by the driver strength and the wire resistance, For the The voltage on the wire, For the The voltage on the wire, For the The voltage on the root wire; Step S102 also includes calculating the three-way signal parallel transmission mode before the crosstalk elimination, for any of the three signals Calculate the delay of converting any value of the three signals to other different values ​​using a wire , and calculate all delays The average value of the three-way signal parallel transmission method before crosstalk elimination is used to obtain the average delay; the four-way signal parallel transmission method after crosstalk elimination is used to calculate the average delay of any of the four signals. Calculate the delay of converting any value of the four signals to other different values ​​using a wire , and calculate all delays The average value of the average delay in the four-way signal parallel transmission mode after crosstalk elimination is obtained; the average delay in the four-way signal parallel transmission mode after crosstalk elimination is subtracted from the average delay in the three-way signal parallel transmission mode before crosstalk elimination to obtain the delay optimization effect of the multi-channel data transmission crosstalk elimination method based on digital coding.

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