Method and system for realizing optical fiber interconnection transmission by high-speed serial transceiver based on FPGA (Field Programmable Gate Array)

Abstract

The invention relates to the technical field of optical fiber communication, in particular to a method and a system for realizing optical fiber interconnection transmission by a high-speed serial transceiver based on an FPGA (Field Programmable Gate Array). Constructing a link feature baseline and combining with a multi-dimensional weighted quality index to drive an improved particle swarm algorithm to dynamically adjust a pre-emphasis coefficient and a receiving equalization parameter of the transceiver; signal jitter characteristics are extracted, clock data are dynamically adjusted based on the jitter characteristics and the bit error rate to recover the loop bandwidth, a forward error correction mode is dynamically switched through hysteresis threshold logic, and time delay and error correction capability are balanced; and continuously updating the baseline parameters through a closed-loop feedback mechanism to realize real-time adjustment and optimization of the quality of the optical fiber communication link.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber communication, and specifically to a method and system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver. Background Art

[0002] With the rapid development of optical fiber communication, optical fiber interconnection technology has become the core transmission solution due to its high bandwidth, low latency, and anti-interference capabilities. However, in high-speed optical fiber transmission, signals are affected by factors such as optical fiber dispersion, temperature fluctuations, and mechanical vibrations, resulting in problems such as an increase in bit error rate (BER), eye diagram closure, and increased jitter; moreover, traditional solutions mostly use fixed parameter equalization, which easily limits the quality of the optical fiber communication link.

[0003] Therefore, a method and system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver are proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver. The present invention constructs a link feature baseline by combining the bit error rate BER and eye diagram feature parameters of the optical fiber link in real time, and drives an improved particle swarm optimization algorithm to dynamically adjust the pre-emphasis coefficient and receive equalization parameters of the transceiver by combining multi-dimensional weighted quality indicators; extracts the signal jitter characteristics, dynamically adjusts the clock data recovery loop bandwidth based on the jitter characteristics and bit error rate, and dynamically switches the forward error correction mode through a hysteresis threshold logic to balance the latency and error correction ability; continuously updates the baseline parameters through a closed-loop feedback mechanism to realize real-time optimization of the optical fiber communication link quality.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver, including:

[0007] S1. Obtain the bit error rate BER and eye diagram feature parameters of the received signal during the optical fiber transmission process. The eye diagram feature parameters include eye height EH and eye width EW; establish a link feature baseline by combining the BER and eye diagram feature parameters.

[0008] S2. Construct a multi-dimensional weighted quality indicator MQM, which is calculated by fusing the normalized scoring function and weight coefficients of BER, EH, and EW; drive an improved particle swarm optimization algorithm in the FPGA to adjust the transmit pre-emphasis coefficient and receive equalization parameters of the high-speed serial transceiver based on the MQM.

[0009] S3. Extract the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and the jitter peak, and dynamically adjust the clock data recovery (CDR) loop bandwidth according to the jitter characteristics and the current bit error rate (BER) to balance the jitter tracking ability and the noise suppression performance, and precisely control the recovery of the optical signal using the non-linear mapping rule;

[0010] S4. Filter the BER data and calculate the trend slope, and dynamically switch the FEC mode in combination with the BER, the trend slope, and the preset hysteresis threshold logic to optimize the signal transmission delay;

[0011] S5. Update the baseline parameters in real time, form a closed loop, and continuously optimize the optical fiber link quality.

[0012] Preferably, the optical fiber transmission process includes the optoelectronic conversion, modulation, and demodulation processes. The FPGA realizes the modulation of the optical signal through the embedded high-speed serial transceiver, and transmits the modulated optical signal to the optical fiber link, and restores the optical signal through the demodulation process at the receiving end.

[0013] Preferably, the improved particle swarm optimization algorithm in S2 includes the following process:

[0014] S2.1. Initialize the parameter ranges of the pre-emphasis coefficient and the receive equalization parameter, and randomly generate the initial particle swarm. The position of each particle represents a set of parameter combinations;

[0015] S2.2. Calculate the MQM of each particle under the current parameters; estimate the gradient of the MQM with respect to the parameters using the finite difference method; and update the current velocity of the particle based on the gradient;

[0016] S2.3. Continue the iteration; if the change rate of the MQM is less than the threshold, it is determined that the convergence is achieved and the optimal parameter combination is output.

[0017] Preferably, the non-linear mapping rule in S3 is implemented through a look-up table. The input of the look-up table is the joint quantization interval of the jitter indicator factor and the bit error rate, and the output is the preset CDR bandwidth level.

[0018] Preferably, the joint quantization interval is used for the joint analysis of the jitter interval and the BER interval; the jitter interval includes the low jitter interval, the medium jitter interval, and the high jitter interval; the BER interval includes the low bit error interval, the medium bit error interval, and the high bit error interval.

[0019] Preferably, the hysteresis threshold logic in S4 is defined as:

[0020] When the BER exceeds the threshold T up and the trend slope is greater than 0, switch from the low error correction mode to the high error correction mode;

[0021] When the BER is less than the threshold T upAnd when the trend slope is less than 0, switch from the high error correction mode to the low error correction mode.

[0022] An optical fiber interconnection transmission system implemented based on an FPGA high-speed serial transceiver, the system includes:

[0023] A link feature baseline construction module, which obtains the bit error rate BER and eye diagram feature parameters of the received signal during the optical fiber transmission process. The eye diagram feature parameters include the eye height EH and the eye width EW; combines the BER and the eye diagram feature parameters to establish a link feature baseline;

[0024] An equalization optimization module, which constructs a multi-dimensional weighted quality metric MQM. The MQM is calculated by fusing the normalized scoring functions and weight coefficients of the BER, EH, and EW; based on the MQM, drives the improved particle swarm algorithm in the FPGA to adjust the transmit pre-emphasis coefficient and the receive equalization parameters of the high-speed serial transceiver;

[0025] An optical signal control module, which extracts the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and the jitter peak value, and dynamically adjusts the clock data recovery CDR loop bandwidth according to the jitter characteristics and the current BER to balance the jitter tracking ability and the noise suppression performance, and uses a non-linear mapping rule to precisely control the recovery of the optical signal;

[0026] A signal transmission delay optimization module, which filters the BER data and calculates the trend slope, combines the BER, the trend slope, and the preset hysteresis threshold logic, dynamically switches the FEC mode, and optimizes the signal transmission delay;

[0027] A feedback module, which updates the baseline parameters in real time, forms a closed loop, and continuously optimizes the optical fiber link quality;

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. By real-time monitoring of the BER, eye diagram feature parameters (EH / EW), and jitter characteristics, constructing a multi-dimensional weighted quality metric (MQM), and dynamically adjusting the pre-emphasis coefficient and the receive equalization parameters in combination with the improved particle swarm algorithm, the present invention can effectively improve the quality of the optical fiber communication link.

[0030] 2. Based on the multi-dimensional weighted quality metric, the present invention calculates the partial derivatives of the parameters to be optimized (the transmit pre-emphasis coefficient and the receive equalization parameters) to obtain the gradient, and updates the velocity of the particle swarm algorithm based on the gradient, and dynamically adjusts the transmit pre-emphasis coefficient and the receive equalization parameters, so as to be able to achieve the convergence ability of the particle swarm algorithm and effectively improve the quality of the optical fiber communication link.

[0031] 3. The present invention determines the joint quantization interval based on the jitter characteristics and BER data, dynamically adjusts the CDR bandwidth level through a look-up table (LUT), and dynamically switches the FEC mode through the hysteresis threshold logic, enhancing the signal jitter suppression ability and effectively improving the quality of the optical fiber communication link.

[0032] 4. The present invention realizes the closed-loop control of the optical fiber link quality by dynamically adjusting the baseline parameters, thereby effectively improving the quality of the optical fiber communication link. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic flowchart of a method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided by an embodiment of the present invention;

[0034] Figure 2 It is a schematic structural diagram of a system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] Embodiment 1

[0037] In order to improve the quality of the A optical fiber communication link, a method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver is applied. As Figure 1 It is a schematic flowchart of a method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided by an embodiment of the present invention, including:

[0038] The method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver includes:

[0039] S1. Obtain the bit error rate BER and eye diagram characteristic parameters of the received signal during the optical fiber transmission process. The eye diagram characteristic parameters include the eye height EH and the eye width EW; combine the BER and the eye diagram characteristic parameters to establish a link characteristic baseline;

[0040] The link characteristic baseline is [BER0, EH0, EW0]; where BER0 represents the initial bit error rate; EH0 represents the initial eye height; EW0 represents the initial eye width.

[0041] Further, the eye diagram characteristic parameters are obtained by capturing the signal waveforms of 1000 consecutive UI (Unit Interval) in the FPGA, superimposing them to generate an eye diagram, and obtaining the eye height EH and the eye width EW.

[0042] S2. Construct a multi-dimensional weighted quality metric MQM, which is calculated by fusing the normalized scoring functions and weight coefficients of BER, EH, and EW.

[0043] The multi-dimensional weighted quality metric is expressed as:

[0044] MQM = κ1 * S BER + κ2 * S EH + κ3 * S EW ;

[0045] where MQM represents the multi-dimensional weighted quality metric; S BER represents the normalized scoring function of bit error rate; S EH represents the normalized scoring function of eye height; S EW represents the normalized scoring function of eye width; κ1, κ2, and κ3 represent weight coefficients.

[0046] The normalized scoring function of bit error rate is:

[0047]

[0048] where BER represents the bit error rate; BER re represents the reference value of bit error rate; BER re takes 1e-3;

[0049] The normalized scoring function of eye height is:

[0050]

[0051] where EH re represents the reference value of eye height;

[0052] The normalized scoring function of eye width is:

[0053]

[0054] where EW re represents the reference value of eye width;

[0055] Further, the optical fiber transmission process includes optoelectronic conversion, modulation, and demodulation processes. The FPGA realizes the modulation of optical signals through the embedded high-speed serial transceiver and transmits the modulated optical signals to the optical fiber link. The optical signals are restored through the demodulation process at the receiving end.

[0056] Adjust the transmit pre - emphasis coefficient and receive equalization parameters of the high - speed serial transceiver based on the improved particle swarm algorithm driven by MQM in the FPGA;

[0057] Furthermore, the improved particle swarm algorithm in S2 includes the following optimization processes:

[0058] S2.1. Initialize the parameter ranges of the pre - emphasis coefficient and receive equalization parameters, and randomly generate an initial particle swarm. The position of each particle represents a set of parameter combinations;

[0059] The parameter combination consists of the pre - emphasis coefficient and each equalizer tap coefficient;

[0060] S2.2. Calculate the MQM under the current parameters of each particle; estimate the gradient of MQM with respect to the parameters using the finite - difference method; and update the current velocity of the particle based on the gradient;

[0061] The gradient is:

[0062]

[0063] where ILI j represents the partial derivative of MQM with respect to the parameter p to be optimized j ; Δ represents the perturbation step size; MQM(p j +Δ) represents the MQM value after positive perturbation; MQM(p j -Δ) represents the MQM value after negative perturbation;

[0064] The updated velocity is:

[0065]

[0066] where v i t+1 represents the updated velocity of particle i at time t + 1; v i t represents the velocity of particle i at time t; ι j represents the weight of the parameter p to be optimized j ; M represents the number of parameters to be optimized;

[0067] The parameter dynamic adjustment process is:

[0068] p j new = p j old + η * ILI j ;

[0069] where p j new represents the adjustment value of the parameter p to be optimized j ; p jold denote the parameter p to be optimized j ; η represents the learning rate;

[0070] S2.3. Continue iteration; if the change rate of MQM is less than the threshold, it is determined to converge and output the optimal parameter combination;

[0071] In this embodiment, by monitoring the BER, eye diagram characteristic parameters (EH / EW) and jitter characteristics in real time, constructing a multi-dimensional weighted quality metric (MQM), and dynamically adjusting the pre-emphasis coefficient and receive equalization parameters in combination with an improved particle swarm optimization algorithm, the quality of the optical fiber communication link can be effectively improved.

[0072] Based on the multi-dimensional weighted quality metric, the present invention calculates the partial derivatives of the parameters to be optimized (transmission pre-emphasis coefficient and receive equalization parameters) to obtain the gradient, and updates the velocity of the particle swarm optimization algorithm based on the gradient, and dynamically adjusts the transmission pre-emphasis coefficient and receive equalization parameters, so as to achieve the convergence ability of the particle swarm optimization algorithm and effectively improve the quality of the optical fiber communication link.

[0073] S3. Extract the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and the jitter peak value, and dynamically adjust the clock data recovery CDR loop bandwidth according to the jitter characteristics and the current BER to balance the jitter tracking ability and the noise suppression performance, and use the non-linear mapping rule to precisely control the recovery of the optical signal;

[0074] The jitter characteristics are extracted from the received signal by LSTM;

[0075] Further, the non-linear mapping rule in S3 is implemented by a look-up table, the input of the look-up table is the joint quantization interval of the jitter indication factor and the bit error rate, and the output is the preset CDR bandwidth level.

[0076] The jitter indication factor is obtained based on the jitter standard deviation and the jitter peak value; the jitter indication factor is:

[0077] TJ = β1 * DJ + β2 * IJ;

[0078] where TJ represents the jitter indication factor; DJ represents the jitter standard deviation; IJ represents the jitter peak value; β1 and β2 represent the jitter indication factor influence coefficients;

[0079] Further, the joint quantization interval is used to jointly analyze the jitter interval and the BER interval; the jitter interval includes a low jitter interval, a medium jitter interval and a high jitter interval; the BER interval includes a low bit error interval, a medium bit error interval and a high bit error interval.

[0080] When TJ ≤ TJ1, it is a low jitter interval; when TJ1 < TJ < TJ2, it is a medium jitter interval; when TJ2 < TJ, it is a high jitter interval; TJ1 and TJ2 are the first jitter indication factor threshold and the second jitter indication factor threshold respectively;

[0081] When BER ≤ BER1, it is a low bit error interval; when BER1 < BER < BER2, it is a medium bit error interval; when BER2 < BER, it is a high bit error interval; BER1 and BER2 are the first bit error rate threshold and the second bit error rate threshold respectively; The look-up table is shown in Table 1;

[0082] Table 1 Look-up table

[0083] Jitter interval Error code interval CDR bandwidth level Low jitter interval Low error code interval Low width Low jitter interval Medium error code interval Medium width Low jitter interval High error code interval High width Medium jitter interval Low error code interval Medium width Medium jitter interval Medium error code interval Medium width Medium jitter interval High error code interval High width High jitter interval Low error code interval High width High jitter interval Medium error code interval High width High jitter interval High error code interval High width

[0084] S4. Filter the BER data and calculate the trend slope. Combine BER, trend slope and the preset hysteresis threshold logic to dynamically switch the FEC mode and optimize the delay of signal transmission;

[0085] The filtering includes weighted averaging through real-time BER data and historical BER data, with weights of 0.1 and 0.9 respectively;

[0086] And select the filtered BER data within the past time window for linear regression, fit the slope of the straight line to obtain the trend slope; The trend slope is:

[0087]

[0088] where k represents the trend slope; n represents the number of sampling points in the time window; t i represents the time stamp; BER i represents the filtered BER value at time t i ;

[0089] Furthermore, the hysteresis threshold logic in S4 is defined as:

[0090] When BER exceeds the threshold T up and the trend slope is greater than 0, switch from the low error correction mode to the high error correction mode;

[0091] When BER is less than the threshold T up and the trend slope is less than 0, switch from the high error correction mode to the low error correction mode.

[0092] This embodiment determines the joint quantization interval based on the jitter characteristics and BER data, dynamically adjusts the CDR bandwidth level through the look-up table (LUT), and dynamically switches the FEC mode through the hysteresis threshold logic, improving the signal jitter suppression ability and effectively improving the quality of the optical fiber communication link.

[0093] S5. Update the baseline parameters in real time to form a closed loop and continuously optimize the quality of the optical fiber link; the updated baseline parameters are: the link characteristic baseline is [BER0 * 0.1 + BER new * 0.9, EH0 * 0.1 + EH new * 0.9, EW0 * 0.1 + EW new * 0.90]; where BER new represents the current bit error rate; EH new represents the current eye height; EW new represents the current eye width.

[0094] In this embodiment, by dynamically adjusting the baseline parameters, closed-loop control of the optical fiber link quality is achieved, thereby effectively improving the quality of the optical fiber communication link.

[0095] Furthermore, the updated baseline parameters are transmitted to the sending end until the MQM change rate is less than the threshold.

[0096] To verify the effectiveness of a method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided in this embodiment, through the quality comparison of different methods applied to the A optical fiber communication link, the quality comparison is carried out by comparing the transmission delay, jitter standard deviation, and BER of different methods; as shown in Table 2 specifically; among them, Method 1 is the method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided in this embodiment; Method 2 is without considering the adjustment of the pre-emphasis coefficient and the receive equalization parameter on the basis of Method 1, Method 3 is without considering the improvement of the particle swarm algorithm on the basis of Method 1; Method 4 is without considering the dynamic adjustment of the CDR bandwidth on the basis of Method 1; Method 5 is without considering the dynamic switching of the FEC mode on the basis of Method 1;

[0097] Table 2 Quality comparison table of different methods applied to the A optical fiber communication link

[0098] Method Transmission delay BER Jitter standard deviation Method 1 40 ns 5e-6 0.1 UI Method 2 60 ns 1e-4 0.3 UI Method 3 50 ns 8e-5 0.2 UI Method 4 55 ns 3e-5 0.2 UI Method 5 50 ns 8e-5 0.3 UI

[0099] As can be seen from Table 2, a method for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided in this embodiment has certain effectiveness.

[0100] Embodiment 2

[0101] To improve the quality of the B optical fiber communication link, a system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver is applied, as Figure 2 is a schematic structural diagram of a system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver provided in an embodiment of the present invention, including:

[0102] A system for realizing optical fiber interconnection transmission based on an FPGA high-speed serial transceiver, the system includes:

[0103] Link feature baseline construction module, which obtains the bit error rate (BER) and eye diagram feature parameters of the received signal during optical fiber transmission. The eye diagram feature parameters include the eye height (EH) and the eye width (EW); combines the BER and the eye diagram feature parameters to establish a link feature baseline;

[0104] The link feature baseline is [BER0, EH0, EW0]; where BER0 represents the initial bit error rate; EH0 represents the initial eye height; EW0 represents the initial eye width.

[0105] Furthermore, the eye diagram feature parameters are obtained by capturing the signal waveforms of 1000 consecutive UI (Unit Interval) in the FPGA, superimposing them to generate an eye diagram; and obtaining the eye height (EH) and the eye width (EW);

[0106] Equalization optimization module, which constructs a multi-dimensional weighted quality metric (MQM). The MQM is calculated by fusing the normalized scoring functions and weight coefficients of BER, EH, and EW;

[0107] The multi-dimensional weighted quality metric is expressed as:

[0108] MQM = κ1 * S BER + κ2 * S EH + κ3 * S EW ;

[0109] Where, MQM represents the multi-dimensional weighted quality metric; S BER represents the normalized scoring function of the bit error rate; S EH represents the normalized scoring function of the eye height; S EW represents the normalized scoring function of the eye width; κ1, κ2, and κ3 represent the weight coefficients;

[0110] The normalized scoring function of the bit error rate is:

[0111]

[0112] Where, BER represents the bit error rate; BER re represents the reference value of the bit error rate; BER re takes 1e-3;

[0113] The normalized scoring function of the eye height is:

[0114]

[0115] Where, EH re represents the reference value of the eye height;

[0116] The normalized scoring function of the eye width is:

[0117]

[0118] Among them, EW re represents the reference value of the eye width;

[0119] Based on the improved particle swarm optimization algorithm in the MQM-driven FPGA, adjust the transmit pre-emphasis coefficient and receive equalization parameters of the high-speed serial transceiver;

[0120] Furthermore, the improved particle swarm optimization algorithm in S2 includes the following optimization processes:

[0121] S2.1. Initialize the parameter ranges of the pre-emphasis coefficient and receive equalization parameters, randomly generate the initial particle swarm, and the position of each particle represents a set of parameter combinations;

[0122] The parameter combination consists of the pre-emphasis coefficient and each equalizer tap coefficient;

[0123] S2.2. Calculate the MQM of each particle under the current parameters; estimate the gradient of the MQM with respect to the parameters using the finite difference method; and update the current velocity of the particle based on the gradient;

[0124] The said gradient is:

[0125]

[0126] Among them, ILI j represents the partial derivative of the MQM with respect to the parameter p to be optimized j ; Δ represents the perturbation step size; MQM(p j +Δ) represents the MQM value after positive perturbation; MQM(p j -Δ) represents the MQM value after negative perturbation;

[0127] The updated velocity is:

[0128]

[0129] Among them, v i t+1 represents the updated velocity of particle i at time t + 1; v i t represents the velocity of particle i at time t; ι j represents the weight of the parameter p to be optimized j ; M represents the number of parameters to be optimized;

[0130] The parameter dynamic adjustment process is:

[0131] p j new = p j old + η * ILI j ;

[0132] where p j new represents the adjustment value of the parameter p to be optimized j ; p j old represents the initial value of the parameter p to be optimized; η represents the learning rate; j

[0133] S2.3. Continue the iteration; if the change rate of MQM is less than the threshold, it is determined that convergence occurs and the optimal parameter combination is output;

[0134] An optical signal control module extracts the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and the jitter peak value, and dynamically adjusts the clock data recovery CDR loop bandwidth according to the jitter characteristics and the current BER to balance the jitter tracking ability and the noise suppression performance, and uses a look-up table LUT to precisely control the recovery of the optical signal;

[0135] The jitter characteristics are extracted from the received signal through LSTM;

[0136] Furthermore, the optical fiber transmission process includes the optoelectronic conversion, modulation, and demodulation processes. The FPGA realizes the modulation of the optical signal through the embedded high-speed serial transceiver, and transmits the modulated optical signal to the optical fiber link, and restores the optical signal through the demodulation process at the receiving end.

[0137] Furthermore, the improved particle swarm algorithm includes the following optimization processes:

[0138] Initialize the parameter ranges of the pre-emphasis coefficient and the receive equalization parameter, and randomly generate an initial particle swarm. The position of each particle represents a set of parameter combinations;

[0139] Calculate the MQM of each particle under the current parameters; estimate the gradient of the MQM with respect to the parameters by using the finite difference method; and update the current velocity of the particle based on the gradient;

[0140] Continue the iteration; if the change rate of MQM is less than the threshold, it is determined that convergence occurs and the optimal parameter combination is output.

[0141] Furthermore, the non-linear mapping rule is implemented through a look-up table. The input of the look-up table is the joint quantization interval of the jitter indication factor and the bit error rate, and the output is the preset CDR bandwidth level.

[0142] The jitter indication factor is obtained based on the jitter standard deviation and the jitter peak value; the jitter indication factor is:

[0143] TJ = β1 * DJ + β2 * IJ;

[0144] ​Among them, TJ represents the jitter indication factor; DJ represents the jitter standard deviation; IJ represents the jitter peak; β1 and β2 represent the jitter indication factor influence coefficients;

[0145] Furthermore, the joint quantization interval is used for joint analysis of the jitter interval and the BER interval; the jitter interval includes a low jitter interval, a medium jitter interval, and a high jitter interval; the BER interval includes a low bit error interval, a medium bit error interval, and a high bit error interval.

[0146] When TJ ≤ TJ1, it is a low jitter interval; when TJ1 < TJ < TJ2, it is a medium jitter interval; when TJ2 < TJ, it is a high jitter interval; TJ1 and TJ2 are the first jitter indication factor threshold and the second jitter indication factor threshold respectively;

[0147] When BER ≤ BER1, it is a low bit error interval; when BER1 < BER < BER2, it is a medium bit error interval; when BER2 < BER, it is a high bit error interval; BER1 and BER2 are the first bit error rate threshold and the second bit error rate threshold respectively; the look-up table is shown in Table 3;

[0148] Table 3 Look-up Table

[0149] Jitter interval Error code interval CDR bandwidth level Low jitter interval Low error code interval Low width Low jitter interval Medium error code interval Medium width Low jitter interval High error code interval High width Medium jitter interval Low error code interval Medium width Medium jitter interval Medium error code interval Medium width Medium jitter interval High error code interval High width High jitter interval Low error code interval High width High jitter interval Medium error code interval High width High jitter interval High error code interval High width

[0150] Furthermore, the joint quantization interval is used for joint analysis of the jitter interval and the BER interval; the jitter interval includes a low jitter interval, a medium jitter interval, and a high jitter interval; the BER interval includes a low bit error interval, a medium bit error interval, and a high bit error interval.

[0151] The signal transmission delay optimization module filters the BER data and calculates the trend slope, and dynamically switches the FEC mode in combination with the BER, the trend slope, and the preset hysteresis threshold logic to optimize the signal transmission delay;

[0152] The filtering includes weighted averaging of the real-time BER data and the historical BER data, with weights of 0.1 and 0.9 respectively;

[0153] And linear regression is performed on the filtered BER data within the past time window to fit the slope of the straight line to obtain the trend slope; the trend slope is:

[0154]

[0155] Among them, k represents the trend slope; n represents the number of sampling points in the time window; t i represents the time stamp; BER i represents the filtered BER value at time t i ;

[0156] Furthermore, the hysteresis threshold logic is defined as:

[0157] When the BER exceeds the threshold T up and the trend slope is greater than 0, switch from the low error correction mode to the high error correction mode;

[0158] When the BER is less than the threshold T up and the trend slope is less than 0, switch from the high error correction mode to the low error correction mode.

[0159] The feedback module updates the baseline parameters in real time, forms a closed loop, and continuously optimizes the quality of the optical fiber link;

[0160] The updated baseline parameters are:

[0161] [BER0*0.1 + BER new *0.9, EH0*0.1 + EH new *0.9, EW0*0.1 + EW new *0.90]; where BER new represents the current bit error rate; EH new represents the current eye height; EW new represents the current eye width.

[0162] Further, the updated baseline parameters are transmitted to the sending end until the MQM change rate is less than the threshold.

[0163] In order to verify the effectiveness of a fiber optic interconnection transmission system implemented by a high - speed serial transceiver based on FPGA provided in this embodiment, through the quality comparison of different systems applied to the B fiber optic communication link, the quality comparison is carried out by comparing the transmission delay, jitter standard deviation, and BER of different systems; as shown in Table 4 specifically; among them, System 1 is the fiber optic interconnection transmission system implemented by a high - speed serial transceiver based on FPGA provided in this embodiment; System 2 does not consider the adjustment of the pre - emphasis coefficient and the receive equalization parameter on the basis of System 1, System 3 does not consider the improvement of the particle swarm algorithm on the basis of System 1; System 4 does not consider the dynamic adjustment of the CDR bandwidth on the basis of System 1; System 5 does not consider the dynamic switching of the FEC mode on the basis of System 1;

[0164] Table 4 Quality comparison table of different methods applied to the A fiber optic communication link

[0165] System Transmission delay BER Jitter standard deviation System 1 40 ns 5e-6 0.1 UI System 2 50 ns 3e-5 0.3 UI System 3 55 ns 8e-5 0.2 UI System 4 60 ns 8e-5 0.3 UI System 5 50 ns 1e-4 0.4 UI

[0166] As can be seen from Table 4, a fiber optic interconnection transmission system implemented by a high - speed serial transceiver based on FPGA provided in this embodiment has a certain effectiveness.

[0167] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art will appreciate that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for realizing optical fiber interconnection transmission based on FPGA high-speed serial transceiver, characterized in that: include: S1. Obtain the bit error rate BER and eye diagram characteristic parameters of the received signal during optical fiber transmission, where the eye diagram characteristic parameters include eye height EH and eye width EW; combine the BER and eye diagram characteristic parameters to establish a link characteristic baseline; S2. Construct a multi-dimensional weighted quality index MQM, which is calculated by integrating the normalized scoring function and weight coefficient of BER, EH and EW; Based on the improved particle swarm algorithm driven by MQM in FPGA, the transmit pre-emphasis coefficient and receive equalization parameters of high-speed serial transceivers are adjusted; S3. Extract the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and jitter peak value, and dynamically adjust the clock data recovery (CDR) bandwidth according to the jitter characteristics and the current BER to balance the jitter tracking capability and noise suppression performance, and use nonlinear mapping rules to accurately control the recovery of the optical signal; S4. Filter the BER data and calculate the trend slope. Combine the BER, trend slope and preset hysteresis threshold logic to dynamically switch the forward error correction FEC mode to optimize the signal transmission delay. S5. Update baseline parameters in real time to form a closed loop and continuously optimize the fiber link quality.

2. The method for realizing optical fiber interconnection transmission by a high-speed serial transceiver based on FPGA according to claim 1, characterized in that: The optical fiber transmission process includes photoelectric conversion, modulation and demodulation processes. The FPGA realizes the modulation of the optical signal through the embedded high-speed serial transceiver, and transmits the modulated optical signal to the optical fiber link, and restores the optical signal through the demodulation process at the receiving end.

3. The method for realizing optical fiber interconnection transmission based on FPGA high-speed serial transceiver according to claim 1, characterized in that: The improved particle swarm algorithm in S2 includes the following optimization process: S2.

1. Initialize the parameter range of the pre-emphasis coefficient and the receiving equalization parameter, randomly generate an initial particle group, and the position of each particle represents a set of parameter combinations; S2.

2. Calculate the MQM of each particle under the current parameters; Finite difference method is used to estimate the gradient of MQM parameters; and the current velocity of the particle is updated based on the gradient; S2.

3. Continue iterating; if the MQM change rate is less than the threshold, convergence is determined and the optimal parameter combination is output.

4. The method for realizing optical fiber interconnection transmission based on FPGA high-speed serial transceiver according to claim 1, characterized in that: The nonlinear mapping rule in S3 is implemented by a lookup table, the input of which is a joint quantization interval of a jitter indication factor and a bit error rate, and the output of which is a preset CDR bandwidth level.

5. The method for realizing optical fiber interconnection transmission using a high-speed serial transceiver based on FPGA according to claim 4, characterized in that: The joint quantization interval is used to jointly analyze the jitter interval and the BER interval; the jitter interval includes a low jitter interval, a medium jitter interval and a high jitter interval; the BER interval includes a low bit error interval, a medium bit error interval and a high bit error interval.

6. The method for realizing optical fiber interconnection transmission based on FPGA high-speed serial transceiver according to claim 1, characterized in that: The hysteresis threshold logic in S4 is defined as: When BER exceeds the threshold T up And the trend slope is greater than 0, switching from low error correction mode to high error correction mode; When BER is less than the threshold T up And the trend slope is less than 0, switching from high error correction mode to low error correction mode.

7. FPGA-based high-speed serial transceiver realizes optical fiber interconnection transmission system, characterized by: The system comprises: The link characteristic baseline construction module obtains the bit error rate BER and eye diagram characteristic parameters of the received signal during optical fiber transmission. The eye diagram characteristic parameters include eye height EH and eye width EW. Combine the BER and eye diagram characteristic parameters to establish the link characteristic baseline. The equalization optimization module constructs a multi-dimensional weighted quality index MQM, which is calculated by integrating the normalized scoring function and weight coefficient of BER, EH and EW; based on the MQM, the improved particle swarm algorithm in the FPGA is driven to adjust the transmit pre-emphasis coefficient and receive equalization parameters of the high-speed serial transceiver; The optical signal control module extracts the jitter characteristics of the received signal in the optical fiber link, including the jitter standard deviation and jitter peak value, and dynamically adjusts the clock data recovery (CDR) loop bandwidth according to the jitter characteristics and the current BER to balance the jitter tracking capability and noise suppression performance, and uses nonlinear mapping rules to accurately control the recovery of the optical signal; The signal transmission delay optimization module filters the BER data and calculates the trend slope. It combines the BER, trend slope and preset hysteresis threshold logic to dynamically switch the FEC mode and optimize the signal transmission delay. The feedback module updates the baseline parameters in real time, forming a closed loop and continuously optimizing the quality of the optical fiber link.

Images