Method, apparatus and system for determining performance of transmitter, and device and storage medium

Abstract

The present application belongs to the technical field of optical communications. Provided are a method, apparatus and system for determining the performance of a transmitter, and a device and a storage medium. The method comprises: acquiring an optical signal from a transmitter, and generating eye pattern data on the basis of the optical signal, wherein the eye pattern data comprises a first sampling point and a second sampling point; respectively performing sampling at the first sampling point and the second sampling point, so as to obtain a first histogram and a second histogram; performing a noise search on the basis of the first histogram and the second histogram, and determining, under a target symbol error rate threshold value, average information of noise margin information corresponding to the first histogram and noise margin information corresponding to the second histogram; and determining a TDECQ value on the basis of the average information, wherein the TDECQ value is used for representing the performance of the transmitter. By means of the solutions of the present application, a TDECQ value is calculated on the basis of average information of noise margin information corresponding to two sampling points, so that the TDECQ value is more accurate, and the performance of a transmitter is reflected more truly.

Description

Method, apparatus, system, device and storage medium for determining transmitter performance

[0001] This application claims priority to Chinese patent application number 202311199890.9, filed on September 15, 2023, entitled “Method, device, system, equipment and storage medium for determining the performance of a transmitter”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of optical communication technology, and in particular to a method, apparatus, system, device and storage medium for determining transmitter performance. Background Art

[0003] Currently, transmitters use four-level pulse amplitude modulation (PAM-4). The performance of these transmitters is typically measured using the transmitter and dispersion eye closure quaternary (TDECQ) value. TDECQ is measured for high-speed intensity modulation direct detection (IMDD) optical links. The principle of TDECQ is to sample the waveform of the optical signal output by the transmitter to obtain a vertical histogram, which is then used to approximate the signal quality through analysis. Specifically, depending on the sampling time, the sampling process can occur within a small time slot in the eye diagram. To account for jitter at the sampling time, the TDECQ standard specifies the selection of two sampling points: 0.45 unit intervals (UI) and 0.55 UI, symmetrical about the center time. The measured values ​​corresponding to the two sampling points are calculated, and the worst of the two measured values ​​is used to calculate the final TDECQ value.

[0004] In high-speed transmission systems, the introduction of advanced digital signal processing (DSP) technology has greatly optimized the accuracy of sampling points. As the sampling rate increases, the lateral opening of the eye in the eye diagram decreases, resulting in the performance of sampling at the 0.45UI and 0.55UI positions being significantly worse than that at 0.5UI. This significant deviation may lead to inaccurate TDECQ values.

[0005] Summary of the Invention

[0006] The present application provides a method, apparatus, system, device, and storage medium for determining transmitter performance, which can make the TDECQ value more accurate and more realistically reflect the transmitter performance when using two sampling points.

[0007] In a first aspect, the present application provides a method for determining the performance of a transmitter, the method comprising: obtaining an optical signal from the transmitter, generating eye diagram data based on the optical signal, the eye diagram data including a first sampling point and a second sampling point, sampling at the first sampling point and the second sampling point, respectively, to obtain a first histogram and a second histogram, performing a noise search based on the first histogram and the second histogram, determining the average information of the residual noise information corresponding to the first histogram and the residual noise information corresponding to the second histogram under a target symbol error rate threshold, and determining a TDECQ value based on the average information, wherein the TDECQ value is used to characterize the performance of the transmitter.

[0008] In the solution presented in this application, two sampling points are used in the eye diagram data to obtain two histograms. These two histograms are then used to perform a noise search to obtain the average of the residual noise information corresponding to the two histograms at the target symbol error rate threshold. This average information is then used to determine the TDECQ value. This not only maintains the original intention of designing two sampling points, but also makes the TDECQ value more accurate and more realistically reflects the performance of the transmitter.

[0009] In an optional manner, when determining the average information, a noise search is performed based on the first histogram to obtain the standard deviation of the first residual noise under the target symbol error rate threshold, and a noise search is performed based on the second histogram to obtain the standard deviation of the second residual noise under the target symbol error rate threshold, and the average information is determined based on the standard deviation of the first residual noise and the standard deviation of the second residual noise.

[0010] In the scheme shown in the present application, when determining the average information, noise searches are performed on the first histogram and the second histogram respectively, so that the symbol error rate corresponding to the first histogram is closer to the target symbol error rate threshold, and a more accurate residual noise is determined, and the symbol error rate corresponding to the second histogram is closer to the target symbol error rate threshold, and a more accurate residual noise is determined. The average information corresponding to the more accurate residual noise is used to calculate the TDECQ value, so that the TDECQ value is more accurate.

[0011] In an optional manner, when the standard deviation of the first residual noise and the standard deviation of the second residual noise are used to determine the average information, according to the formula Determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first residual noise, σ G,R is the standard deviation of the second residual noise.

[0012] In the solution shown in this application, the root mean square of the standard deviation of the two residual noises is used as the average information, so that the TDECQ value is more accurate.

[0013] In an optional manner, when the standard deviation of the first residual noise and the standard deviation of the second residual noise are used to determine the average information, according to the formula σ G =(σ G,L +σ G,R ) / 2, determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first residual noise, σ G,R is the standard deviation of the second residual noise.

[0014] In the solution shown in this application, the average value of the standard deviation of the two residual noises is used as the average information, continuing the original intention of designing two sampling points, and no square root calculation is required, the calculation is simple, and computing resources can be saved.

[0015] In an optional manner, the process of determining the average information is:

[0016] According to the formula Determine the average information, where σ G is the average information, argmin means taking the minimum value, SER L (σ G ) and SER R (σ G ) are the symbol error rate corresponding to the first histogram and the symbol error rate corresponding to the second histogram when noise search is performed based on the first histogram and the second histogram, respectively.

[0017] In the solution shown in the present application, the residual noise corresponding to the first histogram and the second histogram is set to the same, and the average symbol error rate is used to measure the gap with the target symbol error rate threshold. Only one standard deviation of the residual noise is to be determined, and only one noise search is required, which can save half the noise search time and reduce the complexity of determining the TDECQ value.

[0018] In an alternative approach, according to the formula Determine the TDECQ value, where σ G is the average information, σ ideal is the ideal noise corresponding to the transmitter.

[0019] In a second aspect, the present application provides an apparatus for determining transmitter performance, which has the function of implementing the above-mentioned first aspect. The apparatus includes at least one module, and the at least one module is used to implement the method for determining transmitter performance provided in the above-mentioned first aspect.

[0020] In some embodiments, the modules in the apparatus for determining the performance of the transmitter are implemented by software, and the modules in the apparatus are program modules. In other embodiments, the modules in the apparatus are implemented by hardware or firmware.

[0021] In a third aspect, the present application provides a computing device comprising a processor and a memory, wherein: the memory stores computer instructions, and the processor executes the computer instructions to implement the processing of obtaining the TDECQ value based on the eye diagram data in the first aspect and its optional implementation method.

[0022] In a fourth aspect, the present application provides a computer-readable storage medium storing computer instructions. When the computer instructions in the computer-readable storage medium are executed by a computing device, the computing device executes the processing of obtaining the TDECQ value based on the eye diagram data in the first aspect and its optional implementation method.

[0023] In a fifth aspect, the present application provides a computer program product comprising instructions, which, when executed on a computing device, enables the computing device to execute the processing of obtaining a TDECQ value based on eye diagram data in the first aspect and its optional implementation.

[0024] In a sixth aspect, the present application provides a test system, the test system comprising: a reference receiver and a computing device;

[0025] The reference receiver is used to: acquire an optical signal from a transmitter, and generate eye diagram data according to the optical signal, wherein the eye diagram data includes a first sampling point and a second sampling point;

[0026] The computing device is used to: perform sampling at a first sampling point and a second sampling point respectively to obtain a first histogram and a second histogram;

[0027] Performing a noise search based on the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and the residual noise information corresponding to the second histogram under a target symbol error rate threshold;

[0028] A TDECQ value is determined based on the average information, and the TDECQ value is used to characterize the performance of the transmitter. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a schematic diagram of a TDECQ error caused by a sampling time deviation provided by an exemplary embodiment of the present application;

[0030] FIG2 is a schematic structural diagram of a test system provided by an exemplary embodiment of the present application;

[0031] FIG3 is a schematic structural diagram of a test system provided by another exemplary embodiment of the present application;

[0032] FIG4 is a schematic structural diagram of a test system provided by yet another exemplary embodiment of the present application;

[0033] FIG5 is a flow chart of a method for determining transmitter performance provided by an exemplary embodiment of the present application;

[0034] FIG6 is a schematic diagram of a framework for determining transmitter performance provided by an exemplary embodiment of the present application;

[0035] FIG7 is a schematic diagram of a framework for determining transmitter performance provided by another exemplary embodiment of the present application;

[0036] FIG8 is a schematic diagram of a framework for determining transmitter performance provided by yet another exemplary embodiment of the present application;

[0037] FIG9 is a schematic diagram of simulation verification of TDECQ value when the root mean square is used as average information provided by an exemplary embodiment of the present application;

[0038] FIG10 is a schematic diagram showing a comparison of TDECQ value estimation errors provided by an exemplary embodiment of the present application;

[0039] FIG11 is a schematic diagram of simulation verification of TDECQ value when the average value is used as average information provided by an exemplary embodiment of the present application;

[0040] FIG12 is a schematic diagram of simulation verification of a TDECQ value when performing a noise search according to an exemplary embodiment of the present application;

[0041] FIG13 is a structural diagram of an apparatus for determining transmitter performance provided by an exemplary embodiment of the present application;

[0042] FIG14 is a schematic diagram of the structure of a computing device provided by an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0044] Transmitter performance directly impacts receiver signal quality. Before a transmitter is officially deployed, it is tested to determine its performance. Transmitter performance is typically measured using the TDECQ value, making its determination crucial. Current techniques for determining TDECQ values ​​reduce the lateral eye opening in the eye diagram as the sampling rate increases. This results in significantly worse performance at two sampling points (0.45UI and 0.55UI) than at 0.5UI. This significant deviation can lead to inaccurate TDECQ values. For example, Figure 1 provides a schematic diagram of the TDECQ error caused by the deviation of the central sampling moment, specifically the changing trend of the TDECQ value as the sampling point shifts to the left. Figure 1 shows the TDECQ error caused by the deviation of the sampling moment under two modulation methods. The vertical axis represents the TDECQ value in dB, and the horizontal axis represents the offset of the sampling point toward the left. The solid line represents the externally modulated laser (EML) modulation method, and the dotted line represents the silicon photonics (SIP) Mach-Zehnder modulator (Mach-Zehnder In the MZM (Multi-Zero-Monitor Modulator) modulation scheme, solid line 1 shows the TDECQ value corresponding to sampling point A as sampling point A shifts to the left, solid line 2 shows the TDECQ value corresponding to sampling point B as sampling point B shifts to the left, dashed line 1 shows the TDECQ value corresponding to sampling point A as sampling point A shifts to the left, dashed line 2 shows the TDECQ value corresponding to sampling point B as sampling point B shifts to the left. The deviations for sampling points A and B are 0.45 UI and 0.55 UI, respectively. Figure 1 shows that the greater the deviation, the greater the TDECQ error. Furthermore, following the traditional correction approach would inevitably reduce the time interval between the left and right sampling points, which would defeat the original intention of designing two sampling points.

[0045] In an embodiment of the present application, in order to improve the problem of underestimating the performance of the transmitter in the standard TDECQ value determination method, the last step of determining the TDECQ value is adjusted, and the TDECQ value is calculated based on the worst value of the residual noise corresponding to the two histograms, and is modified to be calculated based on the average information of the residual noise information corresponding to the two histograms. This not only continues to use the original intention of designing two sampling points, but also makes the TDECQ value more accurate and more truly reflects the performance of the transmitter.

[0046] To facilitate understanding of the embodiments of the present application, a test system for determining the performance of a transmitter is described below.

[0047] In one optional approach, the test system includes a transmitter, a reference receiver, and a detection device (see Figure 2). The transmitter is an optical transmitter, referred to as the transmitter under test (TUT). The reference receiver, also known as a standard receiver, includes a detector, an oscilloscope, and a feed forward equalizer (FFE). The oscilloscope can be a real-time sampling oscilloscope with a 4th-order Bessel–Thomson response. The FFE is a commonly used linear equalizer that corrects voltage values ​​by removing the effects of intersymbol interference (ISI) and can have a 5-tap symbol rate sampling rate. If the detection device is a hardware device, it is a processing device capable of determining TDECQ values ​​using eye diagram data. For example, it can be a terminal device or a computing device such as a server. If the detection device is a software device, it is deployed on a processing device capable of determining TDECQ values ​​using eye diagram data. The transmitter and reference receiver are connected via an optical fiber.

[0048] The transmitter transmits an optical signal, which is transmitted via optical fiber to a reference receiver. The reference receiver receives the optical signal, and the detector converts it into an electrical signal. The oscilloscope acquires the waveform of this electrical signal in a sequence based on the clock extracted by the clock recovery unit. The FFE performs equalization compensation on the acquired electrical signal sequence. This equalization compensation allows the determination of optical parameters such as the optical modulation amplitude (OMA) of the optical signal transmitted by the transmitter.

[0049] When testing transmitter performance, the tester turns on the transmitter and loads a test signal, a fixed-length signal sequence. This test signal is random and simulates data transmitted in a real-world optical transmission scenario. The transmitter modulates the test signal using PAM4 to generate an optical signal, which is then transmitted via optical fiber to a reference receiver. The reference receiver receives the optical signal at the test point.

[0050] The detector converts the received optical signal into an electrical signal, and the oscilloscope collects the complete signal sequence corresponding to the electrical signal. The FFE synthesizes this complete signal sequence into an eye diagram, generating eye diagram data. An eye diagram is a graph displayed on an oscilloscope by accumulating a series of digital signals.

[0051] The test device uses eye diagram data to calculate the TDECQ value, which is used to characterize transmitter performance. A smaller TDECQ value indicates that the optical signal received by the reference receiver has less power margin loss relative to the ideal signal, meaning it can be transmitted over a longer distance in the optical fiber.

[0052] In one optional approach, the test system includes a transmitter and a reference receiver, as shown in Figure 3. In addition to signal processing, the reference receiver also calculates the TDECQ value using eye diagram data. For example, an oscilloscope can calculate the TDECQ value using eye diagram data. The detection device is an oscilloscope, or the detection device is a software device deployed on an oscilloscope.

[0053] Optionally, in the test systems shown in Figures 2 and 3, the test system also includes an optical receiver (see Figure 4). This optical receiver is used to determine the power penalty of the optical signal received from the transmitter. This power penalty is used to subsequently calibrate the TDECQ value measurement, specifically to adjust the positions of the two sampling points during the TDECQ measurement. For example, if a certain type of transmitter has a unique design that causes the TDECQ value to be excessive, the power penalty can be used to adjust the positions of the two sampling points. The optical receiver is no longer needed when subsequently determining the performance of the transmitter.

[0054] The following describes the method flow for determining the performance of a transmitter in conjunction with FIG. 5 , referring to steps 501 to 504 in FIG. 5 .

[0055] Step 501: Acquire an optical signal from the transmitter, and generate eye diagram data according to the optical signal, where the eye diagram data includes a first sampling point and a second sampling point.

[0056] In this embodiment, the reference receiver receives an optical signal sent by a transmitter through an optical fiber. The optical signal is a signal to be tested, and the signal to be tested is an optical signal generated by modulating a test signal by the transmitter using a PAM4 method.

[0057] The detector converts the signal to be measured into an electrical signal, and the oscilloscope acquires the complete signal sequence corresponding to the signal to be measured. The FFE synthesizes this complete signal sequence into an eye diagram, generating eye diagram data. The detection device obtains eye diagram data from the FFE. The eye diagram can be understood as the process of continuously superimposing new signals onto the current waveform, with a repetition time of one UI. As long as the accumulation time is long enough, an eye diagram is formed. The horizontal axis of the eye diagram is time, and the vertical axis is voltage. The eye diagram data is the voltage value at each time point in the eye diagram.

[0058] Step 502: Sampling is performed at a first sampling point and a second sampling point respectively to obtain a first histogram and a second histogram.

[0059] In this embodiment, the detection device samples the eye diagram data at a first sampling point to obtain a first histogram, and samples the eye diagram data at a second sampling point to obtain a second histogram. Both the first histogram and the second histogram are histograms that count the frequency of occurrence of levels. For example, in the first histogram, the horizontal axis represents the level, including 0, 1, 2, and 3, and the vertical axis represents the frequency of occurrence of each level at the first sampling point. In the second histogram, the horizontal axis represents the level, including 0, 1, 2, and 3, and the vertical axis represents the frequency of occurrence of each level at the second sampling point.

[0060] The detailed processing procedures of step 501 and step 502 can be found in the processing procedures defined in the standard and will not be repeated here.

[0061] In one optional embodiment, the first sampling point and the second sampling point are located to the left and right of 0.5UI, and are symmetrical about 0.5UI. For example, the first sampling point is at 0.45UI and the second sampling point is at 0.55UI. In practice, if the sampling timing is not accurate, the sampling points may not be exactly 0.45UI and 0.55UI, and there may be some deviation.

[0062] Step 503 : Perform noise search based on the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and the residual noise information corresponding to the second histogram under a target symbol error rate threshold.

[0063] The target symbol error rate threshold (TSER) is the decision threshold for forward error correction (FEC). It refers to the maximum symbol error rate (SER) at which an optical signal transmitted by a transmitter can be correctly decoded by an optical receiver. The TSER threshold is related to the transmitter's transmission bandwidth, process technology, transmitted optical signal power, and transmission distance.

[0064] In step 503, there are multiple ways to determine the average information. Two feasible ways are provided below:

[0065] Method 1: Use the first histogram to perform a noise search to obtain the standard deviation of the first residual noise at the target symbol error rate threshold. Use the second histogram to perform a noise search to obtain the standard deviation of the second residual noise at the target symbol error rate threshold. Then, use the standard deviation of the first and second residual noises to calculate the average information.

[0066] The process of using the first histogram for noise search is the same as the process of using the second histogram for noise search. The process of using the first histogram for noise search is described below: pressure noise is added to the electrical signal output by the oscilloscope. The electrical signal and the pressure noise are input into the FFE together. The detection device uses the first histogram and the pressure noise to estimate the symbol error rate and determine whether the symbol error rate reaches the target symbol error rate threshold. If not, the pressure noise is continued to be added before the FFE until the symbol error rate reaches the target symbol error rate threshold. The first pressure noise when the target symbol error rate threshold is reached is determined. The first pressure noise is multiplied by the noise enhancement coefficient to obtain the standard deviation of the first residual noise corresponding to the first pressure noise, which is expressed using formula (1). The noise enhancement coefficient is calculated using the tap coefficient of the FFE. Similarly, the second histogram is used for noise search to obtain the second pressure noise when the target symbol error rate threshold is reached. The second pressure noise is multiplied by the noise enhancement coefficient to obtain the standard deviation of the second residual noise corresponding to the second pressure noise, which is expressed using formula (2). Optionally, in order to more quickly find the stress noise when the target symbol error rate threshold is reached, a binary search method may be used to perform noise search.

[0067] σ G,L =C eq σ eq,L (1)

[0068] σ G,R =C eq σ eq,R (2)

[0069] In formula (1) and formula (2), σ G,L is the standard deviation of the first residual noise, σ G,R is the standard deviation of the second margin noise, C eq is the noise enhancement factor, σ eq,L is the first pressure noise, σ eq,R is the second pressure noise.

[0070] Next, average information is determined based on the standard deviation of the first residual noise and the standard deviation of the second residual noise. The processing process is as follows:

[0071] The root mean square of the standard deviation of the first residual noise and the standard deviation of the second residual noise is determined, and the root mean square is determined as the average information, which is expressed using formula (3), see the framework diagram shown in FIG6 .

[0072] The calculation method calculated by formula (3) adopts the average TDECQ value corresponding to the two histograms to improve the estimation accuracy of TDECQ.

[0073] Alternatively, the average value of the standard deviation of the first residual noise and the standard deviation of the second residual noise is determined, and the average value is determined as the average information, which is expressed using formula (4), see the framework diagram shown in FIG7 .

[0074] σ G =(σ G,L +σ G,R ) / twenty four)

[0075] In formula (3) and formula (4), σ G is the average information, σ G It can be considered as the standard deviation of the target margin noise, σ G,L is the standard deviation of the first residual noise, σ G,R is the standard deviation of the second residual noise.

[0076] The calculation method of formula (4) is used to average the residual noise corresponding to the two histograms to achieve the effect of averaging the TDECQ values ​​corresponding to the two histograms. Compared with the calculation method using formula (3), it can save square root operations and reduce the computational complexity.

[0077] It should be noted that when the root mean square is used to determine the TDECQ value, the variance of the first residual noise and the variance of the second residual noise may also be obtained, and the two variances may be substituted into formula (3) to calculate the TDECQ value.

[0078] Method 2: During the noise search, the residual noise corresponding to the first histogram and the second histogram is the same. The average symbol error rate corresponding to the first histogram and the second histogram is used to measure the gap with the target symbol error rate threshold. In this processing method, there is only one standard deviation of the residual noise to be calculated. The processing method is:

[0079] The average information is determined according to formula (5), and the average information is the standard deviation of the residual noise, see the framework diagram shown in FIG8 .

[0080] In formula (5), σ G is the average information, Indicates Minimum σ G The value of SER L (σ G ) and SER R (σ G ) are the symbol error rate corresponding to the first histogram and the symbol error rate corresponding to the second histogram when noise search is performed based on the first histogram and the second histogram, respectively.

[0081] In the second approach, the pressure noise corresponding to the first and second histograms is set to be the same, and the average symbol error rate is used to measure the gap with the target symbol error rate threshold. Only one standard deviation of the residual noise is required, and only one noise search is required, which can save half the noise search time and reduce the complexity of determining the TDECQ value.

[0082] Step 504: Determine a TDECQ value based on the average information, wherein the TDECQ value is used to characterize the performance of the transmitter.

[0083] In this embodiment, after the average information is determined, the TDECQ value is calculated according to formula (6).

[0084] In formula (6), σ G is the average information, σ ideal is the ideal noise corresponding to the transmitter, and is the maximum noise added under ideal conditions.

[0085] In order to better illustrate the advantages of the embodiments of the present application, a simulation analysis is provided below.

[0086] Figure 9 provides a schematic diagram of the simulation verification of the TDECQ value when the RMS is used as the average information. Figure 9 shows the trend of the TDECQ value when the sampling point shifts to the left. The center moment is 0.5UI, the first sampling point and the second sampling point are 0.45UI and 0.55UI, respectively. The vertical axis represents the TDECQ value, and the horizontal axis represents the offset of the sampling point to the left. Taking EML and SiP-MZM as examples, solid lines a, b, and c represent the trend of the TTDECQ value as the sampling point shifts to the left under EML modulation. The vertical coordinates of the points on solid line a are the TDECQ values ​​corresponding to the first histogram, the vertical coordinates of the points on solid line b are the TDECQ values ​​corresponding to the second histogram, and the vertical coordinates of the points on solid line c are the TDECQ values ​​calculated using the RMS calculation described above. Dashed lines a, b, and c represent the changing trend of the TTDECQ value as the sampling point shifts to the left under the SiP-MZM modulation mode. The ordinate of the point on dashed line a is the TDECQ value corresponding to the first histogram, the ordinate of the point on dashed line b is the TDECQ value corresponding to the second histogram, and the ordinate of the point on dashed line c is the TDECQ value obtained using the above-mentioned root mean square calculation. The TDECQ values ​​shown by solid line a and dashed line a are calculated based on formula (7). The TDECQ values ​​shown by solid line b and dashed line b are calculated based on formula (8).

[0087] In formula (7) and formula (8), σ G,L is the standard deviation of the first residual noise, σG,R is the standard deviation of the second residual noise, σ ideal is the ideal noise corresponding to the transmitter.

[0088] As can be seen from Figure 9, at the standard 0.5UI position (offset equals 0), there is a difference of about 2.5dB between the TDECQ values ​​corresponding to the first histogram and the second histogram, and this difference is very sensitive to the sampling point. The TDECQ value obtained based on the root mean square scheme proposed in this application is not sensitive to the sampling point and is always smaller than the current standard TDECQ value. The current standard TDECQ value is the maximum value of the TDECQ value corresponding to the first histogram and the TDECQ value corresponding to the second histogram (equivalent to taking the minimum value of the standard deviation of the first residual noise and the standard deviation of the second residual noise). It can be seen that the root mean square calculation scheme does not need to reduce the distance between the two sampling points, thereby not violating the original intention of designing two sampling points.

[0089] Figure 10 provides a schematic diagram of the TDECQ value error when using RMS as the average information. In Figure 10, the vertical axis represents the TDECQ value, and the horizontal axis represents the symbol error rate. Taking EML and SiP-MZM as examples, curves 1, 2, and 4 correspond to the EML modulation method, and curves 3, 5, and 6 correspond to the SiP-MZM modulation method. Curves 1 and 3 represent the TDECQ value determined by other methods as the symbol error rate changes, curves 4 and 6 represent the standard TDECQ value as the symbol error rate changes, and curves 2 and 5 represent the TDECQ value calculated based on RMS as the symbol error rate changes. As shown in Figure 10, using RMS as the average information brings the TDECQ value closer to the standard TDECQ value, significantly improving the error.

[0090] Figure 11 provides a schematic diagram of the simulation verification of the TDECQ value when the average value is used as the average information. Taking EML and SiP-MZM as examples, it can be seen that the sensitivity to the sampling point is slightly greater than that of the RMS value as the average information, but it is still significantly better than the sampling point sensitivity of the current standard TDECQ value determination process.

[0091] Figure 12 provides a schematic diagram of the simulation verification of the TDECQ value in Method 2. Taking EML and SiP-MZM as examples, it can be seen that the sensitivity to the sampling point is slightly greater than using the RMS value as the average information or the average value as the average information, but it is still significantly better than the sampling point sensitivity in the current standard TDECQ value determination process.

[0092] Figures 11 and 12 are identical to Figure 9 except for the solid line c and the dashed line c. In Figure 11, the vertical coordinates of the points on the solid line c represent the TDECQ values ​​calculated using the aforementioned average value under EML modulation, while the vertical coordinates of the points on the dashed line c represent the TDECQ values ​​calculated using the aforementioned average value under SiP-MZM modulation. In Figure 12, the vertical coordinates of the points on the solid line c represent the TDECQ values ​​calculated using the aforementioned average symbol error rate under EML modulation, while the vertical coordinates of the points on the dashed line c represent the TDECQ values ​​calculated using the aforementioned average symbol error rate under SiP-MZM modulation.

[0093] In the embodiment of the present application, the TDECQ value is calculated using the above average information, which can improve the estimation accuracy of TDECQ while maintaining a conservative estimate. It can also reduce the dependence on the sampling point location, thereby reducing the dependence on the accuracy of the sampling clock.

[0094] The device provided in the embodiments of the present application is described below.

[0095] Figure 13 is a block diagram of an apparatus for determining transmitter performance according to an embodiment of the present application. The apparatus can be implemented as part or all of the apparatus through software, hardware, or a combination of both. The apparatus provided in an embodiment of the present application can implement the process described in Figure 5 of the embodiment of the present application. The apparatus includes: a signal processing module 1310 and a performance determination module 1320, wherein:

[0096] The signal processing module 1310 is used to: obtain an optical signal from the transmitter; generate eye diagram data according to the optical signal, wherein the eye diagram data includes a first sampling point and a second sampling point; and can be used to implement the signal processing of step 501 and execute the implicit steps included in step 501;

[0097] The performance determination module 1320 is configured to: perform sampling at a first sampling point and a second sampling point respectively to obtain a first histogram and a second histogram;

[0098] Performing a noise search based on the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and the residual noise information corresponding to the second histogram under a target symbol error rate threshold;

[0099] Based on the average information, a four-phase transmitter dispersion eye closure cost TDECQ value is determined. The TDECQ value is used to characterize the performance of the transmitter. Specifically, it can be used to implement the performance determination function of steps 502 to 504 and execute the implicit steps included in steps 502 to 504.

[0100] In an optional manner, the performance determination module 1320 is configured to:

[0101] Performing a noise search based on the first histogram to obtain a standard deviation of a first margin noise at the target symbol error rate threshold, and performing a noise search based on the second histogram to obtain a standard deviation of a second margin noise at the target symbol error rate threshold;

[0102] The average information is determined according to a standard deviation of the first headroom noise and a standard deviation of the second headroom noise.

[0103] In an optional manner, the performance determination module 1320 is configured to:

[0104] According to the formula Determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

[0105] In an optional manner, the performance determination module 1320 is configured to:

[0106] According to the formula σ G =(σ G,L +σ G,R ) / 2 ， Determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

[0107] In an optional manner, the performance determination module 1320 is configured to:

[0108] According to the formula Determine the average information, where σ G is the average information, argmin means taking the minimum value, SER L (σ G ) and SER R (σ G ) are respectively the symbol error rate corresponding to the first histogram and the symbol error rate corresponding to the second histogram when noise search is performed according to the first histogram and the second histogram.

[0109] In an optional manner, the performance determination module 1320 is configured to:

[0110] According to the formula Determine the TDECQ value, where σ G is the average information, σ idealis the ideal noise corresponding to the transmitter.

[0111] The detailed process of determining the performance of a transmitter by the apparatus shown in FIG13 is described in the previous embodiments and will not be repeated here. The apparatus shown in FIG13 includes the reference receiver and the detection apparatus shown in the figure.

[0112] In some embodiments, the present application also provides a computing device 100. As shown in FIG14 , computing device 100 includes a bus 102, a processor 104, a memory 106, and a communication interface 108. Processor 104, memory 106, and communication interface 108 communicate with each other via bus 102. Computing device 100 can be a server or a terminal device. It should be understood that the present application does not limit the number of processors and memories in computing device 100.

[0113] Bus 102 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, among others. Buses may be classified as address buses, data buses, control buses, and the like. For ease of illustration, FIG14 illustrates a single bus line, but this does not imply a single bus or type of bus. Bus 102 may include a path for transmitting information between various components of computing device 100 (e.g., memory 106, processor 104, and communication interface 108).

[0114] The processor 104 may include any one or more processors such as a central processing unit (CPU), a graphics processing unit (GPU), a microprocessor (MP), or a digital signal processor (DSP).

[0115] The memory 106 may include volatile memory, such as random access memory (RAM). The memory 106 may also include non-volatile memory, such as read-only memory (ROM), flash memory, hard disk drive (HDD), or solid state drive (SSD).

[0116] The memory 106 stores executable computer instructions, and the processor 104 executes the executable computer instructions to implement the functions of the aforementioned performance determination module.

[0117] The communication interface 108 uses a transceiver module such as, but not limited to, a network interface card or a transceiver to implement communication between the computing device 100 and other devices or a communication network.

[0118] In some embodiments, a computer program product is provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computing device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computing device to perform the process from step 502 to step 504.

[0119] Those skilled in the art will appreciate that the various method steps and units described in the embodiments disclosed in this application can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the steps and components of each embodiment have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0120] In the several embodiments provided in this application, it should be understood that the disclosed system architecture, device and method can be implemented in other ways. For example, the device embodiment described above is only schematic. For example, the division of the module is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, or it can be an electrical, mechanical or other form of connection.

[0121] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0122] In addition, each module in each embodiment of the present application can be integrated into a processing module, each module can exist physically separately, or two or more modules can be integrated into a module. The above-mentioned integrated modules can be implemented in the form of hardware or software modules.

[0123] If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0124] In this application, the terms "first" and "second" are used to distinguish between identical or similar items with substantially the same effects and functions. It should be understood that there is no logical or temporal dependency between "first" and "second," nor is there any limitation on quantity or order of execution. It should also be understood that although the following description uses the terms "first" and "second" to describe various elements, these elements should not be limited by the terms. These terms are merely used to distinguish one element from another. For example, without departing from the scope of the various examples, the first residual noise may be referred to as the second residual noise, and similarly, the second residual noise may be referred to as the first residual noise. Both the first residual noise and the second residual noise may be residual noise, and in some cases, may be separate and different residual noises.

[0125] The above description is merely an exemplary embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for determining the performance of a transmitter, characterized in that The method comprises: acquiring an optical signal from the transmitter; generating eye diagram data according to the optical signal, the eye diagram data comprising a first sampling point and a second sampling point; Sampling is performed at the first sampling point and the second sampling point respectively to obtain a first histogram and a second histogram; Performing a noise search according to the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and residual noise information corresponding to the second histogram under a target symbol error rate threshold; According to the average information, a four-phase transmitter dispersion eye diagram closure cost TDECQ value is determined, and the TDECQ value is used to characterize the performance of the transmitter.

2. The method according to claim 1, characterized in that The performing noise search according to the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and residual noise information corresponding to the second histogram under a target symbol error rate threshold includes: Performing a noise search according to the first histogram to obtain a standard deviation of a first residual noise at the target symbol error rate threshold, and performing a noise search according to the second histogram to obtain a standard deviation of a second residual noise at the target symbol error rate threshold; The average information is determined according to a standard deviation of the first residual noise and a standard deviation of the second residual noise.

3. The method according to claim 2, characterized in that The determining the average information according to the standard deviation of the first residual noise and the standard deviation of the second residual noise includes: According to the formula Determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

4. The method according to claim 2, characterized in that: The determining the average information according to the standard deviation of the first residual noise and the standard deviation of the second residual noise includes: According to the formula σ G =(σ G,L +σ G,R ) / 2, determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

5. The method according to claim 1, characterized in that The performing noise search according to the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and residual noise information corresponding to the second histogram under a target symbol error rate threshold includes: According to the formula Determine the average information, where σ G is the average information, argmin means taking the minimum value, SER L (σ G ) and SER R (σ G ) are respectively the symbol error rate corresponding to the first histogram and the symbol error rate corresponding to the second histogram when noise search is performed according to the first histogram and the second histogram.

6. The method according to any one of claims 1 to 5, characterized in that: Determining the TDECQ value according to the average information includes: According to the formula Determine the TDECQ value, where σ G is the average information, σ ideal is the ideal noise corresponding to the transmitter.

7. An apparatus for determining the performance of a transmitter, characterized in that The device comprises: The signal processing module is used to: obtain an optical signal from the transmitter; generate eye diagram data according to the optical signal, wherein the eye diagram data includes a first sampling point and a second sampling point; The performance determination module is used to: perform sampling at the first sampling point and the second sampling point respectively to obtain a first histogram and a second histogram; Performing a noise search according to the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and residual noise information corresponding to the second histogram under a target symbol error rate threshold; According to the average information, a four-phase transmitter dispersion eye diagram closure cost TDECQ value is determined, and the TDECQ value is used to characterize the performance of the transmitter.

8. The device according to claim 7, characterized in that The performance determination module is used to: Performing a noise search according to the first histogram to obtain a standard deviation of a first residual noise at the target symbol error rate threshold, and performing a noise search according to the second histogram to obtain a standard deviation of a second residual noise at the target symbol error rate threshold; The average information is determined according to a standard deviation of the first residual noise and a standard deviation of the second residual noise.

9. The device according to claim 8, characterized in that The performance determination module is used to: According to the formula Determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

10. The device according to claim 8, characterized in that The performance determination module is used to: According to the formula σ G =(σ G,L +σ G,R ) / 2, determine the average information, where σ G is the average information, σ G,L is the standard deviation of the first margin noise, σ G,R is the standard deviation of the second margin noise.

11. The device according to claim 7, characterized in that The performance determination module is used to: According to the formula Determine the average information, where σ G is the average information, argmin means taking the minimum value, SER L (σ G ) and SER R (σ G ) are respectively the symbol error rate corresponding to the first histogram and the symbol error rate corresponding to the second histogram when noise search is performed according to the first histogram and the second histogram.

12. The device according to any one of claims 7 to 11, characterized in that The performance determination module is used to: According to the formula Determine the TDECQ value, where σ G is the average information, σ ideal is the ideal noise corresponding to the transmitter.

13. A testing system, characterized in that: The test system includes: a reference receiver and a computing device; The reference receiver is used to: acquire an optical signal from a transmitter; generate eye diagram data according to the optical signal, wherein the eye diagram data includes a first sampling point and a second sampling point; The computing device is used to: perform sampling at the first sampling point and the second sampling point respectively to obtain a first histogram and a second histogram; Performing a noise search according to the first histogram and the second histogram to determine average information of residual noise information corresponding to the first histogram and residual noise information corresponding to the second histogram under a target symbol error rate threshold; A four-phase transmitter dispersion eye diagram closure cost TDECQ value is determined according to the average information, wherein the TDECQ value is used to characterize the performance of the transmitter.

14. A computing device, characterized in that The computing device comprises a processor and a memory, wherein: The memory stores computer instructions; The processor executes the computer instructions to enable the computing device to perform the process of obtaining the TDECQ value according to the eye diagram data in any one of claims 1 to 6.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions. When the computer instructions in the computer-readable storage medium are executed by a computing device, the computing device executes the processing of obtaining a TDECQ value based on eye diagram data in any one of claims 1 to 6.

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