APD driving voltage adjustment method and device based on PID system, medium and equipment

Abstract

The present application relates to the technical field of optical communication, and in particular to an APD driving voltage adjustment method, device, medium and equipment based on a PID system. The APD driving voltage adjustment method comprises the following steps: calculating the difference between the average AD value and the saturated AD value of the current output of the APD, determining whether the current target driving voltage of the APD is the optimal working voltage, and when it is determined that the current target driving voltage of the APD is not the optimal working voltage, calculating the expected target driving voltage of the APD to adjust the current target driving voltage of the APD until the current target driving voltage of the APD is the optimal working voltage. According to the present application, the PID control system is adjusted, the actual value and the target value are continuously converged to the target value, the amplitude of voltage adjustment is not too large, and the damage risk of the APD is reduced.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and in particular to an APD drive voltage regulation method, apparatus, medium, and device based on a PID system. Background Technology

[0002] In optical time-domain reflectometers (OTDRs), avalanche photodiodes (APDs) are commonly used as receivers to convert optical signals into electrical signals. Compared to ordinary photodiodes, APDs have higher gain, enabling them to capture weak signals and improve sensitivity. According to the APD's gain characteristic curve, the closer the APD's drive voltage is to its reverse breakdown voltage (VBR), the greater its gain. However, if the APD's drive voltage exceeds VBR, avalanche will occur, and if the drive voltage exceeds VBR too much, it may even break down the APD, leading to equipment damage. Since VBR is strongly correlated with temperature, the APD's drive voltage needs to be adjusted before using the OTDR to ensure it does not exceed VBR, thus maximizing the APD's gain and performance. In practical applications, adjusting the APD's drive voltage cannot be prolonged, otherwise it will consume OTDR scanning time. Therefore, a method is needed to quickly adjust the APD's drive voltage to its optimal level.

[0003] Currently, the conventional method for adjusting the drive voltage of an APD is to use a binary search method to find the optimal voltage. Although this method can significantly shorten the time to find the optimal voltage, when the binary search method drives the APD to a high voltage range to determine if it is optimal, it may cause the APD to operate in a breakdown voltage environment for a short period of time, which still poses a risk of damaging the device. Therefore, this invention is based on a proportional-integral-derivative (PID) control algorithm to adjust the drive voltage of the APD, so that the adjustment range of the APD drive voltage is not too large, reducing the risk of APD damage. Summary of the Invention

[0004] The technical problem to be solved by the embodiments of the present invention is to provide an APD drive voltage regulation method, device, medium and equipment based on a PID system, so as to solve the problem that in the prior art, when the APD is driven to a high voltage range by the binary method to determine whether it is optimal, the APD may work in the breakdown voltage environment for a short time, which may lead to the risk of equipment damage.

[0005] This invention discloses an APD drive voltage regulation method based on a PID system, comprising:

[0006] Obtain the average AD value output by the APD under the current target drive voltage, wherein the analog voltage output by the D / A converter using the default drive voltage value is used as the current target drive voltage;

[0007] Detect whether the obtained mean AD value is within the range where the AD value is close to saturation, and calculate the difference between the current mean AD value and the saturation AD value;

[0008] Based on the calculated difference, determine whether the current target drive voltage of the APD is the optimal operating voltage. If not, calculate the expected target drive voltage of the APD. The formula for calculating the expected target drive voltage is as follows:

[0009]

[0010] in, The desired target drive voltage for the APD. The current target drive voltage of the APD. This is the difference between the current mean AD value and the saturation AD value. The proportional gain coefficient of the PID control system;

[0011] Adjust the current target drive voltage of the APD according to the calculated expected target drive voltage, and repeat the above steps S1-S3 until the current target drive voltage of the APD is the optimal operating voltage.

[0012] Optionally, obtaining the average AD value output by the APD under the current target driving voltage includes:

[0013] The analog signal output by the APD is converted into a digital signal by an A / D converter. Multiple AD values ​​continuously output by the APD are sampled over a period of time, and the average value of the AD is obtained by averaging the sampled AD values.

[0014] Optionally, the detection of whether the average AD value is within the range where the AD value is close to saturation includes:

[0015] The saturated AD value of the A / D converter output is determined based on the selected A / D converter resolution. An unsaturated but close to saturated AD value is selected as the close to saturated AD value. The range between the close to saturated AD value and the saturated AD value is taken as the close to saturation range of the A / D converter output value.

[0016] Optionally, the method for determining whether the current target driving voltage of the APD is the optimal operating voltage based on the calculated difference includes:

[0017] If 0 < If the value is less than 1, then the current target driving voltage of the APD is considered to be the optimal operating voltage.

[0018] like ≤0, or If the value is ≥1, then the current target driving voltage of the APD is considered to be the non-optimal operating voltage.

[0019] Optionally, after determining that the current target drive voltage of the APD is not the optimal operating voltage, and before calculating the expected target drive voltage of the APD, the method further includes determining whether the difference between the current average AD value and the saturated AD value is too large:

[0020] like >0 and > If the difference between the current mean AD and the saturation AD is too large, then set... = ;

[0021] like <0 and <- If the difference between the current AD mean and the saturation AD value is too large, then... =- ;

[0022] in, This represents the maximum single adjustment amount of the difference.

[0023] Optionally, the method further includes determining whether the difference between the current AD mean and the saturated AD value is too large when the current AD mean is saturated:

[0024] like =0, define a fixed value for the difference between the current AD mean and the saturated AD value, indicating that the current AD mean is higher than the saturated AD value, and then determine whether the difference between the fixed value and the saturated AD value is too large.

[0025] The present invention also discloses an apparatus comprising:

[0026] The first processing unit is used to obtain the average AD value output by the APD under the current target driving voltage;

[0027] The second processing unit is used to detect whether the acquired mean AD value is within the range of AD value close to saturation, and to calculate the difference between the current mean AD value and the saturated AD value;

[0028] The third processing unit is used to determine whether the current target drive voltage of the APD is the optimal working voltage based on the calculated difference. If not, it calculates the expected target drive voltage of the APD based on the PID control algorithm.

[0029] The fourth processing unit is used to adjust the current target drive voltage of the APD according to the calculated expected target drive voltage until the current target drive voltage of the APD is the optimal operating voltage.

[0030] The present invention also discloses a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described APD drive voltage regulation method based on a PID system.

[0031] The present invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described APD drive voltage regulation method based on a PID system.

[0032] Compared with the prior art, the beneficial effects of the APD drive voltage regulation method, device, medium, and equipment based on the PID system provided in the embodiments of the present invention are as follows:

[0033] Based on a PID control system, the difference between the average AD value and the saturated AD value of the current output of the APD is calculated to determine whether the current target drive voltage of the APD is the optimal operating voltage. When it is determined that the current target drive voltage of the APD is not the optimal operating voltage, the expected target drive voltage of the APD is calculated and the current target drive voltage of the APD is adjusted until the current target drive voltage of the APD is the optimal operating voltage. Thus, through the adjustment of the PID control system, the voltage adjustment amplitude can be continuously converged to the target based on the difference between the actual value and the target value, so that the voltage adjustment amplitude is not too large, reducing the risk of damage to the APD. Even if there is overshoot, it is an extremely small process. Compared with the binary method adjustment, the overshoot degree of this invention is greatly reduced, ensuring that the avalanche photodiode as a receiver operates at the optimal performance point and is not damaged. Attached Figure Description

[0034] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0035] Figure 1 This is a schematic block diagram illustrating the steps of the APD drive voltage regulation method provided in an embodiment of the present invention.

[0036] Figure 2 This is a schematic block diagram of the control flow of the APD driving voltage regulation method provided in an embodiment of the present invention. Detailed Implementation

[0037] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0038] This invention provides an APD drive voltage regulation method based on a PID system, such as... Figure 1 and Figure 2 As shown, it includes:

[0039] Obtain the average AD value output by the APD under the current target drive voltage, wherein the analog voltage output by the D / A converter using the default drive voltage value is used as the current target drive voltage;

[0040] Detect whether the obtained mean AD value is within the range where the AD value is close to saturation, and calculate the difference between the current mean AD value and the saturation AD value;

[0041] Based on the calculated difference, it is determined whether the current target drive voltage of the APD is the optimal operating voltage. If not, the expected target drive voltage of the APD is calculated based on the PID control algorithm. The formula for calculating the expected target drive voltage is as follows:

[0042]

[0043] in, The desired target drive voltage for the APD. The current target drive voltage of the APD. This is the difference between the current mean AD value and the saturation AD value. The proportional gain coefficient of the PID control system;

[0044] Adjust the current target drive voltage of the APD according to the calculated expected target drive voltage, and repeat the above steps until the current target drive voltage of the APD is the optimal operating voltage.

[0045] Preferably, the function of the PID control system is to generate a control signal based on the magnitude of the error to adjust the system output. Therefore, pidki can be modified according to the actual adjustment of the PID control system, for example, pidki=0.002.

[0046] Furthermore, the formula for calculating the desired target driving voltage is explained: By adjusting based on PID control, the desired target driving voltage of the APD is calculated, which can be represented by the voltage at each time step (or control cycle) as the current deviation ( The voltage is multiplied by the proportional gain coefficient (pidki), and the result is then added to the current target drive voltage to adjust the drive voltage of the APD, gradually bringing it closer to the target value. This is used in feedback control systems to achieve stability and accuracy of the target value. Therefore, through the adjustment of the PID control system, the difference between the actual value and the target value can be brought closer to the target by continuously converging, preventing the voltage adjustment amplitude from being too large and reducing the risk of damage to the APD.

[0047] As mentioned above, APD stands for avalanche photodiode, a type of photodetector. It has higher sensitivity than traditional photodiodes because it is based on the avalanche breakdown effect. When an incident photon hits the APD and causes an avalanche effect, the generated electrons are amplified, thereby increasing the signal current of the detector.

[0048] In this invention, a D / A converter is used to provide an analog voltage value to drive the APD. This voltage controls the operating state of the APD and is typically used to adjust the APD's gain or threshold. The default drive voltage value refers to the drive voltage value of the device or system under default settings. This is the voltage level used by the device or system without special configuration or adjustment. This voltage value is typically used to control the D / A converter to generate a specific analog signal. Therefore, obtaining the default drive voltage value ensures that the system uses the correct parameters to configure the D / A converter output analog voltage as the current target drive voltage to drive the APD when it starts operating.

[0049] Using a D / A converter to drive an APD offers the following advantages: (1) Precise control: A D / A converter can provide highly accurate analog outputs to control the operating parameters of the APD, such as voltage bias and amplification. This precision ensures that the APD performs optimally at a specific operating point. (2) Programmability: D / A converters are typically programmable and can adjust the output voltage in real time by adjusting the digital input, thus achieving dynamic control. This is very useful for adapting to different optical signal intensities or application requirements. (3) Stability: A D / A converter can provide stable outputs, which helps maintain the stable operating state of the APD. Stable voltage bias and signal amplification help reduce noise and improve the signal-to-noise ratio. (4) Accuracy: D / A converters typically have high resolution and low error, which helps ensure that the measurement results of the APD are highly accurate. (5) Flexibility: Using a D / A converter to drive an APD allows for flexible adaptation to different optical signal intensities, wavelengths, and optical conditions. This means that the same equipment can be used in a variety of different optical environments. (6) Fast response: Digitally controlled D / A converters can provide fast response times, making them suitable for applications that require rapid detection and response to changes in optical signals, such as optical communication.

[0050] Optionally, the method for obtaining the AD average is also included: converting the analog signal output by the APD into a digital signal using an A / D converter, sampling multiple AD values ​​continuously output by the APD over a period of time, and calculating the AD average by averaging the sampled multiple AD values.

[0051] As mentioned above, an A / D converter converts the analog signal output by the APD into a digital signal. Once the APD receives an optical signal and converts it into current or voltage, the A / D converter can then convert the analog signal back into a digital signal. The AD value refers to the digital output value at a single sampling moment of the A / D converter. It represents the strength or characteristics of the analog signal at a specific moment. The AD value is the result of the A / D converter conversion; an AD value is generated at each sampling moment, and these values ​​can be used for applications such as real-time monitoring, data acquisition, and signal analysis. The AD mean is calculated by averaging multiple consecutively sampled AD values; this average value represents the average strength or characteristics of the analog signal over a period of time.

[0052] Optionally, detecting whether the acquired average AD value is within the near-saturation range of the AD value includes: determining the saturated AD value of the A / D converter output based on the selected A / D converter resolution, selecting an AD value that is not saturated but close to the saturated AD value, and taking the numerical range between the selected AD value and the saturated AD value as the near-saturation range of the A / D converter output value.

[0053] For example, a 12-bit resolution A / D converter means that it converts an analog signal into a 12-bit digital signal, typically ranging from 0 to 4095, where 0 represents the minimum value and 4095 represents the maximum value; the output saturation value is 4095. The saturation AD value is the maximum output value of the A / D converter, that is, the largest value the A / D converter can represent. Here, the AD value is chosen to be 4094, so the range to be checked should be between 4094 and 4095. That is, if the A / D converter output value is close to 4095 but has not yet reached 4095, it indicates that the optical signal is relatively strong but has not yet reached the maximum measurement range of the A / D converter; this is considered a near-saturation state. This judgment logic is used to check the output range of the A / D converter to determine whether the optical signal received by the APD is in a near-saturated but not fully saturated state, thereby determining whether the APD is operating at its optimal voltage.

[0054] Optionally, the method for determining whether the current target drive voltage of the APD is the optimal operating voltage based on the calculated difference includes:

[0055] If 0 < If the value is less than 1, then the current target driving voltage of the APD is considered to be the optimal operating voltage.

[0056] like ≤0, or If the value is ≥1, then the current target driving voltage of the APD is considered to be the non-optimal operating voltage.

[0057] Optionally, after determining that the current target drive voltage of the APD is not the optimal operating voltage, and before calculating the expected target drive voltage of the APD, the APD drive voltage adjustment method further includes determining whether the difference between the current average AD value and the saturated AD value is too large:

[0058] like >0 and > If the difference between the current mean AD and the saturation AD is too large, then set... = ;

[0059] like <0 and <- If the difference between the current AD mean and the saturation AD value is too large, then... =- ;

[0060] in, This represents the maximum adjustment amount for a single instance of the difference.

[0061] As described above, by determining whether the difference between the current average AD value and the saturated AD value is too large before calculating the expected target driving voltage of the APD, system overshoot can be avoided during the adjustment of the APD driving voltage.

[0062] Optionally, the APD drive voltage regulation method further includes determining whether the difference between the current average AD value and the saturated AD value is too large when the current average AD value is saturated.

[0063] like =0, define a fixed value for the difference between the current AD mean and the saturated AD value, indicating that the current AD mean is higher than the saturated AD value, and then determine whether the difference between the fixed value and the saturated AD value is too large.

[0064] As mentioned above, when When the value is 0, it indicates that the AD mean has reached saturation. However, the difference between the current AD mean and the saturated AD value is unknown. Therefore, a fixed difference needs to be defined based on the adjustment of the PID control system. ,For example: =-100, thus determining whether the difference between the current average AD value and the saturated AD value is too large.

[0065] The APD drive voltage regulation method based on the PID system of the present invention can, through the regulation of the PID control system, continuously converge the difference between the actual value and the target value to approach the target, so that the voltage regulation amplitude is not too large, reducing the risk of damage to the APD. Even if there is overshoot, it is an extremely small process. Compared with the binary method regulation, the degree of overshoot of the present invention is greatly reduced, ensuring that the avalanche photodiode as a receiver works at the optimal performance point and is not damaged.

[0066] The present invention also discloses an apparatus comprising:

[0067] The first processing unit is used to obtain the average AD value output by the APD under the current target driving voltage;

[0068] The second processing unit is used to detect whether the acquired mean AD value is within the range of AD value close to saturation, and to calculate the difference between the current mean AD value and the saturated AD value;

[0069] The third processing unit is used to determine whether the current target drive voltage of the APD is the optimal working voltage based on the calculated difference. If not, it calculates the expected target drive voltage of the APD based on the PID control algorithm.

[0070] The fourth processing unit is used to adjust the current target drive voltage of the APD according to the calculated expected target drive voltage until the current target drive voltage of the APD is the optimal operating voltage.

[0071] The present invention also discloses a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described APD drive voltage regulation method based on a PID system.

[0072] The present invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described APD drive voltage regulation method based on a PID system.

[0073] This invention is described based on flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to specific embodiments. It should be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the flowcharts and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0074] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0075] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0076] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Those skilled in the art can modify the technical solutions described in the above embodiments, or make equivalent substitutions for some of the technical features; and all such modifications and substitutions should fall within the protection scope of the appended claims of the present invention.

Claims

1. A method for regulating APD drive voltage based on a PID system, characterized in that, The APD drive voltage regulation method includes: Obtain the average AD value output by the APD under the current target drive voltage, wherein the analog voltage output by the D / A converter using the default drive voltage value is used as the current target drive voltage; Detect whether the obtained mean AD value is within the range where the AD value is close to saturation, and calculate the difference between the current mean AD value and the saturation AD value; Based on the calculated difference, determine whether the current target drive voltage of the APD is the optimal operating voltage. If not, calculate the expected target drive voltage of the APD. The formula for calculating the expected target drive voltage is as follows: in, The desired target drive voltage for the APD. The current target drive voltage of the APD. This is the difference between the current mean AD value and the saturation AD value. The proportional gain coefficient of the PID control system; Adjust the current target drive voltage of the APD according to the calculated expected target drive voltage, and repeat the above steps until the current target drive voltage of the APD is the optimal operating voltage.

2. The APD drive voltage regulation method based on a PID system according to claim 1, characterized in that, The process of obtaining the average AD value output by the APD under the current target driving voltage includes: The analog signal output by the APD is converted into a digital signal by an A / D converter. Multiple AD values ​​continuously output by the APD are sampled over a period of time, and the average value of the AD is obtained by averaging the sampled AD values.

3. The APD drive voltage regulation method based on a PID system according to claim 2, characterized in that, Whether the mean AD value obtained by the detection is within the range where the AD value is close to saturation includes: The saturated AD value of the A / D converter output is determined based on the selected A / D converter resolution. An unsaturated but close to saturated AD value is selected as the close to saturated AD value. The range between the close to saturated AD value and the saturated AD value is taken as the close to saturation range of the A / D converter output value.

4. The APD drive voltage regulation method based on a PID system according to claim 1, characterized in that, The method for determining whether the current target driving voltage of the APD is the optimal operating voltage based on the calculated difference includes: If 0 < If the value is less than 1, then the current target driving voltage of the APD is considered to be the optimal operating voltage. like ≤0, or If the value is ≥1, then the current target driving voltage of the APD is considered to be the non-optimal operating voltage.

5. The APD drive voltage regulation method based on a PID system according to claim 4, characterized in that, After determining that the current target drive voltage of the APD is not the optimal operating voltage, and before calculating the expected target drive voltage of the APD, the method further includes determining whether the difference between the current average AD value and the saturated AD value is too large: like >0 and > If the difference between the current mean AD and the saturation AD is too large, then set... = ; like <0 and <- If the difference between the current AD mean and the saturation AD value is too large, then... =- ; in, This represents the maximum adjustment amount for a single instance of the difference.

6. The APD drive voltage regulation method based on a PID system according to claim 5, characterized in that, The method further includes determining whether the difference between the current AD mean and the saturated AD value is too large when the current AD mean is saturated: like =0, define a fixed value for the difference between the current AD mean and the saturated AD value, indicating that the current AD mean is higher than the saturated AD value, and then determine whether the difference between the fixed value and the saturated AD value is too large.

7. An APD drive voltage regulation device based on a PID system, characterized in that, include: The first processing unit is used to obtain the average AD value output by the APD under the current target driving voltage; The second processing unit is used to detect whether the acquired mean AD value is within the range of AD value close to saturation, and to calculate the difference between the current mean AD value and the saturated AD value; The third processing unit is used to determine whether the current target drive voltage of the APD is the optimal working voltage based on the calculated difference. If not, it calculates the expected target drive voltage of the APD based on the PID control algorithm. The fourth processing unit is used to adjust the current target drive voltage of the APD according to the calculated expected target drive voltage until the current target drive voltage of the APD is the optimal operating voltage.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the APD drive voltage regulation method based on the PID system as described in any one of claims 1-6.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the APD drive voltage regulation method based on a PID system as described in any one of claims 1-6.

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