阅读说明：本技术 一种光电探测装置温度模拟补偿方法及系统 (Temperature simulation compensation method and system for photoelectric detection device ) 是由 黄正武 汪松 马晓 杨晨 曹蓓蓓 谭浩柏 于 2021-08-23 设计创作，主要内容包括：本发明公开了一种光电探测装置温度模拟补偿方法及系统。所述方法包括以下步骤：对于特定测的光电探测装置,采用工作温度的二阶多项式函数分别回归拟合光功率值与输出量线性关系的斜率和/或截距,并采用拟合获得的斜率与工作温度的二阶多项式函数和/或斜率与工作温度的二阶多项式函数,根据工作温度对光功率值进行温度补偿。仅需要3个标定温度即可获得光功率值与输出量对数值的线性关系,大大减少了对于光电探测装置进行温度补偿的标定工作,降低了高精度光电探测装置的成本。应用该方法的光电探测系统通过对光电探测器线性拟合工作区段,针对工作温度进行补偿,提高光电探测精度,从而拓宽了光电探测范围。(The invention discloses a temperature simulation compensation method and system for a photoelectric detection device. The method comprises the following steps: for a photoelectric detection device for specific measurement, a second-order polynomial function of working temperature is adopted to respectively carry out regression fitting on the slope and/or intercept of the linear relation between the light power value and the output quantity, the second-order polynomial function of the slope and the working temperature and/or the second-order polynomial function of the slope and the working temperature obtained by fitting are adopted, and temperature compensation is carried out on the light power value according to the working temperature. The linear relation between the optical power value and the output logarithmic value can be obtained only by 3 calibration temperatures, so that the calibration work of temperature compensation on the photoelectric detection device is greatly reduced, and the cost of the high-precision photoelectric detection device is reduced. The photoelectric detection system applying the method compensates for the working temperature by linearly fitting the photoelectric detector to the working section, improves the photoelectric detection precision, and widens the photoelectric detection range.)

1. A temperature simulation compensation method for a photoelectric detection device is characterized by comprising the following steps:

for a photoelectric detection device for specific measurement, a second-order polynomial function of working temperature is adopted to respectively carry out regression fitting on the slope and/or intercept of the linear relation between the light power value and the output quantity, the second-order polynomial function of the slope and the working temperature and/or the second-order polynomial function of the slope and the working temperature obtained by fitting are adopted, and temperature compensation is carried out on the light power value according to the working temperature.

2. The method for analog compensation of temperature of a photo-detection device as claimed in claim 1, wherein the OUTPUT is a logarithmic value of the ADC data sampled by the interface and the detection power P when the photo-detection device is in a specific linear operation section_dbmThe linear relationship of (a) is expressed as:

P_dbm＝K*OUTPUT+C

where K is the slope and C is the intercept.

3. The method for temperature analog compensation of a photodetecting device according to claim 1 or 2, wherein the slope K and intercept C of the logarithmic relationship of the optical power value and the output quantity are respectively fitted with a second order polynomial function of temperature as follows:

K＝a₁*T²+b₁*T+c₁

C＝a₂*T²+b₂*T+c₂

wherein T is the working temperature, a₁、b₁、c₁、a₂、b₂、c₂Parameters for the second order polynomial function are determined by data fitting.

4. The method for analog compensation of temperature of a photodetecting device according to claim 1, wherein the method comprisesThen, the second-order polynomial function of the slope and the working temperature and the second-order polynomial function of the slope and the working temperature obtained by fitting are adopted to carry out temperature compensation on the light power value according to the working temperature, and the temperature-compensated detection power P is adopted_dBmThe calculation is as follows:

P_dBm＝(a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂)。

5. the method for analog compensation of temperature of a photo detection device according to claim 1, wherein the dark current compensation power P is regression-fitted using a second order polynomial function_darkAnd performing dark current compensation on the light power value according to the working temperature by adopting a second-order polynomial function of dark current compensation power and the working temperature obtained by fitting, and detecting power P compensated by the temperature and the dark current_dBmThe calculation is as follows:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂))-dB2mw(P_dark))

wherein dB2mW () is a conversion function to convert dBm value to mW valuemW2dB () is a conversion function to convert mW values to dBm values

P_dark＝a₃*T²+b₃*T+c₃

Wherein, a₃、b₃、c₃Is a parameter of a second order polynomial function.

6. A temperature simulation compensation system of a photoelectric detection device is characterized by comprising a temperature sensor, a memory, a processor and a computer program which is stored on the memory and can run on the processor; the temperature sensor is used for measuring the working temperature of the photoelectric detector, and the processor is used for implementing the temperature simulation compensation method of the photoelectric detection device according to any one of claims 1 to 5 to perform linear fitting and temperature compensation on the logarithm of the output quantity of the photoelectric detector when the computer program is executed according to the working temperature of the photoelectric detector, so as to obtain the detected optical power.

7. A photo-detection system, comprising a photo-detection device and the photo-detection device temperature simulation compensation system as claimed in claim 6, wherein the output of the photo-detection device is outputted to the photo-detection device temperature simulation compensation system, and the photo-detection device temperature simulation compensation system performs linear fitting and temperature compensation on the output of the photo-detector to obtain the detected optical power.

8. The photodetection system according to claim 7 wherein said photodetection means is a linear photodetector or a logarithmic photodetector.

9. The photodetection system according to claim 8 wherein said photodetection device is a linear photodetector comprising a photodiode, a transimpedance amplifier and an operational amplifier in series; the transimpedance amplifier comprises a plurality of control ends and a plurality of shunt resistors, wherein the control ends of the transimpedance amplifier change the electrical performance of the photoelectric detection device by enabling different shunt resistors to be in an access or non-access state, so that the linear photoelectric detector is in different specific linear working sections; the output ends of the trans-impedance amplifier and the operational amplifier respectively output the output quantities of the photoelectric detectors under the electrical properties of different electric detection devices; the temperature simulation compensation system of the photoelectric detection device determines the electrical performance of the photoelectric detection device by reading signals of an access port and a control end of a trans-impedance amplifier, and adopts the slope K, the intercept C and the pick-up value of the corresponding photoelectric detection device under the electrical performanceOr dark current compensation power P_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

10. The photodetection system according to claim 8 wherein said photodetection means is a logarithmic photodetector comprising a photodiode, a logarithmic transimpedance amplifier, and an operational amplifier connected in series; the temperature analog compensation system of the photoelectric detection device acquires the output quantity of the logarithmic photoelectric detector, namely interface sampling ADC data, determines the linear section where the interface sampling ADC data is located according to the interface sampling ADC data, and compensates the power P by adopting the slope K, the intercept C and/or the dark current of the corresponding linear section_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

Technical Field

The invention belongs to the technical field of optical modules, and particularly relates to a temperature simulation compensation method and system for a photoelectric detection device.

Background

With the rapid development of optical communication technology, optical network devices, modules and subsystem products of high-speed communication and data communication applied to optical networks are gradually developed. The generation of erbium-doped fiber amplifiers (EDFAs) is a revolutionary breakthrough in the field of optical fiber communication, which enables long-distance, large-capacity and high-speed optical fiber communication, and is also an indispensable important device for DWDM systems and future high-speed systems and all-optical networks. The related technology of the amplifier, especially the intensive research and application of the PD detection technology, has important significance on the development of optical fiber communication.

Especially, in the construction of core network and backbone network, the related technology of erbium-doped fiber amplifier (EDFA) is deeply researched and applied, which has important significance for the development of optical fiber communication. High performance Erbium Doped Fiber Amplifiers (EDFAs) rely on high precision, ultra wide range photodetection techniques.

At present, the photoelectric detection technology is interfered by a plurality of factors, and especially in the photoelectric detection technology with high precision or low power, the application requirement is difficult to achieve. In order to improve the detection accuracy, an interpolation compensation method is generally adopted, a large number of experiments are required to be performed for different batches to obtain check data, and the development cost is high.

Disclosure of Invention

The invention provides a temperature simulation compensation method and a temperature simulation compensation system for a photoelectric detection device, aiming at compensating working temperature and dark current power by the conventional photoelectric detector detection technology adopting linear fitting, so that the detection precision of the light power in a low power range and a high power range is improved, and the photoelectric detection in a high-precision and ultra-wide range is realized by matching with a multi-section fitting technology, so that the technical problems of low detection precision or limited detection range in the prior art are solved.

In order to achieve the above object, according to one aspect of the present invention, there is provided a method for temperature analog compensation of a photodetecting device, comprising the steps of:

for a photoelectric detection device for specific measurement, a second-order polynomial function of working temperature is adopted to respectively carry out regression fitting on the slope and/or intercept of the linear relation between the light power value and the output quantity, the second-order polynomial function of the slope and the working temperature and/or the second-order polynomial function of the slope and the working temperature obtained by fitting are adopted, and temperature compensation is carried out on the light power value according to the working temperature.

Preferably, in the method for analog temperature compensation of a photodetecting device, when the photodetecting device is in a specific linear operating section, the OUTPUT is the interface sampling ADC data or the logarithm of the ADC data, and the detection power P_dBmThe linear relationship of (a) is expressed as:

P_dBm＝K*OUTPUT+C

where K is the slope and C is the intercept.

Preferably, the temperature analog compensation method for the photoelectric detection device is implemented by respectively fitting a second-order polynomial function of temperature to the slope K and the intercept C of the linear relationship between the optical power value and the logarithmic output value, and specifically includes:

K＝a₁*T²+b₁*T+c₁

C＝a₂*T²+b₂*T+c₂

wherein T is the working temperature, a₁、b₁、c₁、a₂、b₂、c₂Parameters for the second order polynomial function are determined by data fitting.

Preferably, the temperature analog compensation method for the photoelectric detection device adopts a second-order polynomial function of slope and working temperature and a second-order polynomial function of slope and working temperature obtained by fitting, performs temperature compensation on the light power value according to the working temperature, and performs temperature compensation on the detection power P_dBmIs calculated as follows：

P_dBm＝(a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂)。

Preferably, the photoelectric detection device temperature simulation compensation method adopts a second-order polynomial function to perform regression fitting on the dark current compensation power P_darkAnd performing dark current compensation on the light power value according to the working temperature by adopting a second-order polynomial function of dark current compensation power and the working temperature obtained by fitting, and detecting power P compensated by the temperature and the dark current_dBmThe calculation is as follows:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂))-dB2mw(P_dark))

wherein dB2mW () is a conversion function to convert dBm value to mW valuemW2dB () is a conversion function to convert mW values to dBm values

P_dark＝a₃*T²+b₃*T+c₃

Wherein, a₃、b₃、c₃Is a parameter of a second order polynomial function.

According to another aspect of the present invention, there is provided a temperature simulation compensation system for a photodetecting device, comprising a temperature sensor, a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the temperature sensor is configured to measure an operating temperature of the photodetecting device, and the processor is configured to implement the temperature simulation compensation method for photodetecting device according to the present invention to perform linear fitting and temperature compensation on a logarithm of an output quantity of the photodetecting device when executing the computer program according to the operating temperature of the photodetecting device, so as to obtain a detected optical power.

According to another aspect of the present invention, a photodetection system is provided, which includes a photodetection device and the photodetection device temperature simulation compensation system provided by the present invention, wherein the output of the photodetection device is output to the photodetection device temperature simulation compensation system, and the photodetection device temperature simulation compensation system performs linear fitting and temperature compensation on the output of the photodetector to obtain the detected optical power.

Preferably, the photodetection device of the photodetection system is a linear photodetector or a logarithmic photodetector.

Preferably, the photodetection system, the photodetection device of which is a linear photodetector, includes a photodiode, a transimpedance amplifier and an operational amplifier connected in series; the transimpedance amplifier comprises a plurality of control ends and a plurality of shunt resistors, wherein the control ends of the transimpedance amplifier change the electrical performance of the photoelectric detection device by enabling different shunt resistors to be in an access or non-access state, so that the linear photoelectric detector is in different specific linear working sections; the output ends of the trans-impedance amplifier and the operational amplifier respectively output the output quantities of the photoelectric detectors under the electrical properties of different electric detection devices; the temperature simulation compensation system of the photoelectric detection device determines the electrical performance of the photoelectric detection device by reading signals of an access port and a control end of a trans-impedance amplifier, and compensates power P by adopting slope K, intercept C and/or dark current under the electrical performance of the corresponding photoelectric detection device_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

Preferably, the photodetection system, the photodetection device of which is a logarithmic photodetector, includes a photodiode, a logarithmic transimpedance amplifier, and an operational amplifier connected in series; the temperature analog compensation system of the photoelectric detection device acquires the output quantity of the logarithmic photoelectric detector, namely the interface sampling ADC data, according to the output quantityThe interface samples ADC data to determine the linear section in which the ADC data is located, and the slope K, intercept C and/or dark current compensation power P of the corresponding linear section are adopted_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:

the analog compensation method for the photoelectric detection device provided by the invention confirms that the slope and the intercept of the linear relationship between the light power value and the output quantity of the photoelectric detector are influenced by the working temperature through a large amount of experimental data, the change relationship between the slope and the intercept along with the temperature accords with a second-order polynomial, and when a second-order function is adopted to fit the temperature data of a test project, the correlation coefficient R²The temperature and the power output are close to or exceed 0.99, and the regression fitting result shows that the second-order function of the temperature can accurately simulate the slope and the intercept of the linear relation between the optical power value and the output quantity. The linear relation between the optical power value and the output logarithmic value can be obtained only by 3 calibration temperatures, so that the calibration work of temperature compensation on the photoelectric detection device is greatly reduced, and the cost of the high-precision photoelectric detection device is reduced.

The photoelectric detection system provided by the invention compensates for the working temperature by linearly fitting the working section of the photoelectric detector, improves the photoelectric detection precision and widens the photoelectric detection range. Especially aiming at the detection range of low power and compensating for dark current, the detection precision of the linear fitting working section of low power is further improved. The optimal scheme is matched with a photoelectric detector covered by a multi-stage section, so that a high-precision, full-temperature and ultra-wide photoelectric detection range (the detection range is larger than 75dB, and the precision is smaller than 0.5dB) is realized.

Drawings

Fig. 1 is a schematic diagram of a circuit structure of a photodetector provided in embodiment 1 of the present invention;

fig. 2 is a schematic diagram of a circuit structure of a photodetector provided in embodiment 2 of the present invention;

fig. 3 is a schematic view of a linear photoelectric detection system provided in embodiment 1 of the present invention, covering a working range in a segmented manner;

FIG. 4 is a curve showing the variation of the first section (LV1) K of the linear photo-detection system with the temperature T from-5 ℃ to 75 ℃ according to embodiment 1 of the present invention;

FIG. 5 is a curve of the first segment (LV1) C of the linear photo-detection system according to embodiment 1 of the present invention along with the temperature T from-5 ℃ to 75 ℃;

FIG. 6 is a graph of dark current power (dBm) versus temperature T from-5 deg.C to 75 deg.C for a first segment (LV1) of a linear photo-detection system provided in embodiment 1 of the present invention;

FIG. 7 is a schematic structural diagram of a logarithmic photodetection system provided in embodiment 2 of the present invention;

FIG. 8 is a schematic diagram of the segmented coverage working range of the logarithmic photodetection system provided in embodiment 2 of the present invention;

FIG. 9 is a schematic diagram of a piecewise linear fit of a logarithmic photodetection system provided in embodiment 2 of the present invention;

FIG. 10 is a graph showing the variation of the temperature T from-5 deg.C to 75 deg.C along the first segment (LV1) K of the logarithmic photodetector system provided in example 2 of the present invention;

FIG. 11 is a graph showing the variation of the temperature T from-5 deg.C to 75 deg.C in the first segment (LV1) C of the logarithmic photodetector system provided in example 2 of the present invention;

fig. 12 is a graph of dark current power (dBm) versus temperature T from-5 ℃ to 75 ℃ for a first segment (LV1) of a logarithmic photodetector system provided in embodiment 2 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

A photoelectric detector, the sampling value is influenced by temperature, the compensation calculation is needed between the acquisition value of the photoelectric detector and the final optical power aiming at the temperature change, the temperature simulation compensation method of the general photoelectric detection device generally adopts a calibration interpolation method, namely, the acquisition value and the optical power of the photoelectric detector are calibrated at a specific calibration temperature, interpolation is carried out at the temperature among a plurality of calibration temperatures to approximately estimate the difference between the measured value of the optical power and the true value of the optical power calculated by the temperature on the acquisition value of the photoelectric detector, and the temperature compensation is carried out according to the estimated difference. The compensation effect of the method is limited by the density of calibration data, namely the compensation effect is better when the calibrated temperature is more, however, the difference estimation error is always larger because the discrete calibration fitting temperature is calibrated. When the requirement on the precision is high, because more calibration fitting temperatures need to be calibrated, large-scale correction is needed when the device leaves a factory, and the cost is very high.

The temperature simulation compensation method of the photoelectric detection device provided by the invention comprises the following steps:

for a photoelectric detection device for specific measurement, a second-order polynomial function of working temperature is adopted to respectively carry out regression fitting on the slope and/or intercept of the linear relation between the light power value and the output quantity, the second-order polynomial function of the slope and the working temperature and/or the second-order polynomial function of the slope and the working temperature obtained by fitting are adopted, and temperature compensation is carried out on the light power value according to the working temperature.

The experimental data show that: when the temperature is controlled under a constant temperature condition, the test light power and the output quantity of the photoelectric detector form a linear relationship with good line, and when the temperature exceeds 25 ℃, the change of the temperature obviously affects the linear relationship between the light power and the photoelectric detector. Through a large number of engineering temperature data experiments, it is observed that the linear relation between the test luminous power value and the output quantity, if represented by a linear relation, changes along with the temperature change in slope and intercept instead of constant, so that the linear relation between the test luminous power value and the output quantity logarithm value deteriorates when the temperature changes. Further, when a second order function is adopted to fit the test engineering temperature data, the correlation coefficient R²All are close to or exceed 0.99, and the regression fitting result shows that the second-order function of the temperature can accurately simulate the optical power valueSlope and intercept in a linear relationship with output. Theoretically, only 3 calibration temperatures are needed to obtain the linear relation between the optical power value and the output logarithmic value, so that the calibration work for temperature compensation of the photoelectric detection device is greatly reduced, and the cost of the high-precision photoelectric detection device is reduced.

Specifically, when the photo-detection device is in a specific linear operating section, such as a specific electrical performance condition of the linear photo-detector, and as a specific linear fitting section of the logarithmic photo-detector, the OUTPUT is the interface sampling ADC data or the logarithmic value of the ADC data, and the detection power P_dBmThe linear relationship of (a) is expressed as:

P_dBm＝K*OUTPUT+C

wherein, Log10(ADC) is a Log of OUTPUT, K is a slope, C is an intercept, OUTPUT is an OUTPUT, and when the photodetection device is a linear photodetector, OUTPUT, i.e. the Log of ADC data sampled by the interface, is generally Log10(ADC) × 10; when the photodetecting device is a logarithmic photodetector, OUTPUT is the interface that samples the ADC data. Currently, the detection power P is generally obtained by performing linear fitting according to the Log10(ADC) × 10 value of the linear photodetector_dbmThe value is obtained by performing linear fitting according to the ADC value of the logarithmic photoelectric detector_dBmThe value is obtained.

The slope K and the intercept C of the linear relation between the optical power value and the output quantity are respectively fitted by adopting a second-order polynomial function of the temperature, and the method specifically comprises the following steps:

K＝a₁*T²+b₁*T+c₁

C＝a₂*T²+b₂*T+c₂

wherein T is the working temperature, a₁、b₁、c₁、a₂、b₂、c₂Parameters for the second order polynomial function are determined by data fitting. Preferably, the fitting is performed by using the sampling data of three calibration fitting temperatures, preferably, the calibration fitting temperatures are 25 ℃, 45 ℃ and 65 ℃, and considering that the slope K below 25 ℃ and the change of the intercept C with the temperature are small, the calibration fitting temperature below 25 ℃ can be directly 25 DEGThe values of the slope K and the intercept C are such that the accuracy of the calibration fitting at 25 ℃ can be improved in a temperature range below 25 ℃, and in addition, the working environment of the photoelectric detection device is considered, and generally the temperature does not exceed 75 ℃, so that the highest calibration fitting temperature is preferably close to the upper limit of the working environment temperature, 65 ℃ is selected, the intermediate temperature between 25 ℃ and 65 ℃ is taken as the calibration fitting temperature, and a high fitting effect can be obtained with the minimum calibration cost.

And fitting one of the slope K and the intercept C by adopting a second-order polynomial function of the working temperature, namely realizing temperature compensation to a certain extent, improving the accuracy of the photoelectric detection device, and preferably fitting the slope K by adopting the second-order polynomial function of the working temperature to realize temperature compensation. Preferably, the slope K and the intercept C are fitted simultaneously by a second order polynomial function of the operating temperature, so that the temperature compensated probe power P is obtained_dBmThe calculation is as follows:

P_dBm＝(a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂)

in addition, it has been found that when the detected optical power is low, the temperature not only affects the intercept of the slope of the linear relationship between the optical power value and the output logarithm value, but also causes other interference. Repeated experiments confirm that for the optical power detection case, temperature affects the linear relationship between the detection power of the photodetector and the ADC data by affecting the dark current of the photodiodes (including PD and APD).

At lower power, therefore, compensation for temperature-induced dark current interference is required. Through a large amount of engineering temperature data experiments, under the specific linear working section of the photoelectric detection device, the dark current compensation power P_darkWill change with the temperature + by a second order polynomial function, the dark current compensates the power P_darkPerforming regression fitting by using a second-order polynomial function, wherein the calculation method comprises the following steps:

P_dark＝a₃*T²+b₃*T+c₃

wherein, a₃、b₃、c₃Parameterisation as a function of a second order polynomialAnd (4) counting.

Dark current compensation is carried out on the light power value according to the working temperature by adopting a second-order polynomial function of dark current compensation power and the working temperature obtained by fitting, and the detection power P after temperature compensation_dBmThe calculation is as follows:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂))-dB2mw(P_dark))

wherein dB2mW () is a conversion function to convert dBm value to mW valuemW2dB () is a conversion function to convert mW values to dBm values

The temperature simulation compensation system of the photoelectric detection device comprises a temperature sensor, a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the temperature sensor is used for measuring the working temperature of the photoelectric detector, and the processor is used for realizing the linear fitting and the temperature compensation of the logarithm of the output quantity of the photoelectric detector by the temperature simulation compensation method of the photoelectric detection device provided by the invention when executing the computer program according to the working temperature of the photoelectric detector so as to obtain the detected light power.

The photoelectric detection system comprises a photoelectric detection device and a photoelectric detection device temperature simulation compensation system, wherein the output quantity of the photoelectric detection device is output to the photoelectric detection device temperature simulation compensation system, and the photoelectric detection device temperature simulation compensation system carries out linear fitting and temperature compensation on the output quantity of a photoelectric detector to obtain the detection light power.

The photoelectric detection device is a linear photoelectric detector or a logarithmic photoelectric detector.

The preferred scheme is as shown in figure 1, the photoelectric detection device is a linear photoelectric detector, a bagThe photoelectric detector comprises a photodiode, a trans-impedance amplifier and an operational amplifier which are connected in series; the transimpedance amplifier comprises a plurality of control ends and a plurality of shunt resistors, wherein the control ends of the transimpedance amplifier change the electrical performance of the photoelectric detection device by enabling different shunt resistors to be in an access or non-access state, so that the linear photoelectric detector is in different specific linear working sections; the output ends of the trans-impedance amplifier and the operational amplifier respectively output the output quantities of the photoelectric detectors under the electrical properties of different electric detection devices; the temperature simulation compensation system of the photoelectric detection device determines the electrical performance of the photoelectric detection device by reading signals of an access port and a control end of a trans-impedance amplifier, and compensates power P by adopting slope K, intercept C and/or dark current under the electrical performance of the corresponding photoelectric detection device_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

The multi-level sampling of data is realized by changing the electrical performance of the photoelectric detector, and the working ranges of different linear photoelectric detectors are covered by the multi-level sampled data, so that the detection requirement of an ultra-wide range is realized, and the high-precision wide-range photoelectric detection of 75dB or even more is achieved.

Preferably, as shown in fig. 2, the photo-detection device is a logarithmic photo-detector, and includes a photodiode, a logarithmic transimpedance amplifier, and an operational amplifier connected in series; the temperature analog compensation system of the photoelectric detection device acquires the output quantity of the logarithmic photoelectric detector, namely interface sampling ADC data, determines the linear section where the interface sampling ADC data is located according to the interface sampling ADC data, and compensates the power P by adopting the slope K, the intercept C and/or the dark current of the corresponding linear section_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power.

The following are examples:

example 1 Linear photodetector System

The linear photoelectric detection system provided by the embodiment comprises a linear photoelectric detector and a temperature analog compensation system of a photoelectric detection device.

As shown in fig. 1, a linear photodetector includes a Photodiode (PD), a transimpedance amplifier (TIA), and an operational amplifier (OP) connected in series; the transimpedance amplifier comprises a plurality of control ends and a plurality of shunt resistors, wherein the control ends of the transimpedance amplifier change the electrical performance of the photoelectric detection device by enabling different shunt resistors to be in an access or non-access state, so that the linear photoelectric detector is in different specific linear working sections;

the photoelectric TIA (trans-impedance amplifier) + OP (operational amplifier) linear amplification detection control circuit is a bridge between an optical signal and an electric signal, and has wide application in various fields. In the field of optical communication, an optical-electrical TIA (trans-impedance amplifier) + OP (operational amplifier) linear amplification detection circuit is an important approach and method for acquiring an optical signal. The photoelectric TIA (trans-impedance amplifier) + OP (operational amplifier) amplification detection circuit converts an optical signal into a current signal which can be controlled and processed by an integrated circuit, then converts the current signal into a voltage signal, and obtains optical information (intensity of light and the like) through the change of the voltage signal. The photoelectric TIA (trans-impedance amplifier) + OP (operational amplifier) linear amplification detection circuit is an important component, such as a Photodiode (Photodiode), an analog sampling chip (AD7266BCPZ) and the like, and outputs a corresponding current signal by converting the strength of a detection optical signal. Generally, the amplification range of an amplifying and detecting circuit of a photoelectric TIA (transimpedance amplifier) + OP (operational amplifier) is fixed in a narrow range (the detection range is less than 25dB, and the precision is less than 0.5dB), so that the bandwidth of a detected optical signal is narrow, an optical signal in a larger range is too saturated or too small to be detected (the optical signal is too weak, the noise interference is large), and meanwhile, the information of the detected optical signal cannot be accurately reflected due to the dark current phenomenon of a Photodiode (Photodiode).

The input ends of the two control selection switches are connected to the output end TIA of the first-stage amplifier and the output end OP of the second-stage operational amplifier through a first resistor R1, a second resistor R2 and a third resistor R3 by a 3-stage photoelectric TIA (trans-impedance amplifier) + OP (operational amplifier) linear amplification detection control circuit and a control switch selection unit. When the two switches select the first state to output (namely, the 1-stage photoelectric detection TIA + OP linear amplification is opened), the Photodiode (Photodiode) amplifying circuit is connected to pass through the output end TIA of the first resistor R1, and simultaneously, the output end OP of the second-stage amplifying circuit, so that two-stage sampling data (LV1.K/C and LV2.K/C) can be obtained; when the two switches select the second state to output, the Photodiode (Photodiode) amplifying circuit is connected to pass through the output end TIA of the second resistor R2, and simultaneously the output end OP of the second-stage amplifying circuit, so that two-stage sampling data (LV3.K/C and LV4.K/C) can be obtained; when the two switches select the third state to output, the Photodiode (Photodiode) amplifying circuit is connected to pass through the output end TIA of the third resistor R3, and simultaneously, the Photodiode (Photodiode) amplifying circuit passes through the output end OP of the second-stage amplifying circuit, and two-stage sampling data (LV5.K/C and LV6.K/C) can be obtained at the time.

Linear amplified probe data of 6 grades (6 grades: LV1.K/C, LV2.K/C, LV3.K/C, LV4.K/C, LV5.K/C and LV6.K/C, respectively) and dark current (mW) were obtained without considering the temperature change of the Photodiode (Photodiode), and the schematic case is shown in FIG. 3.

The operation mode is as follows: when switch control unit CTL1 and switch control unit CTL2 are combined, four states will result, 00, 01, 10 and 11 respectively (left unused). When the state of the switch control unit (CTL1 and CTL2) is 00, a voltage signal connected with a Photodiode (Photodiode) amplifying circuit outputs a TIA Out end through a first resistor R1(510) to sample 1-level linear amplification data, and simultaneously, a second-level amplifying circuit AMP (31) outputs an OP Out end to sample 2-level linear amplification data. When the state of the switch control unit (CTL1 and CTL2) is 01, a voltage signal connected with a Photodiode (Photodiode) amplifying circuit outputs a TIA Out end through a second resistor R2(330K) to sample 3 rd-level linear amplification data, and simultaneously, a second-level amplifying circuit AMP (31) outputs an OP Out end to sample 4 th-level linear amplification data. And thirdly, when the state of the switch control unit (CTL1 and CTL2) is 10, a voltage signal connected with a Photodiode (Photodiode) amplifying circuit outputs a TIA Out end through a third resistor R3(10M) to sample 5 th-level linear amplification data, and simultaneously, a second-level amplifying circuit AMP (31) outputs an OP Out end to sample 6 th-level linear amplification data. Therefore, 6-level linear amplification detection sampling data can be obtained, and the requirement that the maximum ultra-wide range detection can reach more than or equal to 75dB is met.

The temperature simulation compensation system of the photoelectric detection device adopts a central processing unit and peripheral circuits, hardware of the temperature simulation compensation system consists of a high-speed micro control processor (MCU), a minimum power supply circuit unit of the processor and high-speed DA, AD, PWM and IO ports of the processor, and the hardware is a core part of a control, detection and acquisition circuit module.

The temperature simulation compensation system of the photoelectric detection device determines the electrical performance of the photoelectric detection device by reading signals of an access port and a control end of a trans-impedance amplifier. Using slope K, intercept C, and/or dark current compensation power P at electrical performance of corresponding photo-detection device for a particular level of linearly amplified detection data_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power. The method comprises the following specific steps:

sampling the linear relation between ADC data and detection power through a high-speed AD interface of a high-speed micro-control processor (MCU), and finally obtaining a fitting power formula of each stage as follows:

P_dBm＝K*Log10(ADC)*10+C

the detection range of each level is within 14dB, so that the detection requirement of the ultra-wide range can be met by 6 levels of power detection in sequence, and the maximum power can be more than or equal to 75 dB. The Photodiode (Photodiode) can change along with the change of the environmental temperature during the application process of an erbium-doped fiber amplifier (EDFA). Through a large number of engineering temperature data experiments, it can be seen that the K, C value in the formula changes with the temperature T through a second-order polynomial function.

Taking the first stage as an example: the change curve of K value with temperature T is shown in FIG. 4, R²0.9946; the curve of C value with temperature T is shown in FIG. 5, R²＝0.9903。

From the above K, C values as a function of temperature T, it can be seen that no temperature-dependent compensation can be made below 25 ℃; but temperature variations above 25 c require temperature dependent compensation. The formula for the variation of K, C values with temperature T can be derived by fitting a large number of experimental data as follows (calibration fitting temperatures of 25 deg.C, 45 deg.C and 65 deg.C, respectively):

K＝a₁*T²+b₁*T+c₁

C＝a₂*T²+b₂*T+c₂

wherein T is the working temperature, a₁、b₁、c₁、a₂、b₂、c₂Parameters for the second order polynomial function are determined by data fitting for each segment.

Under the change of ambient temperature, the dark current generated by a Photodiode (Photodiode) in operation is effectively compensated. Dark current colloquially, first, this current is not generated by photons from the outside, but rather from thermal noise inside the element; secondly, any diode has a theoretical characteristic of forward conduction and reverse cut-off, but in reality, a photodiode component cannot be truly cut off in the reverse direction (the reverse saturation current is 0), and finally, the dark current cannot be completely eliminated, and only the influence of the dark current can be reduced by an effective compensation technology (particularly, when the optical signal is weak, the optical power is less than or equal to-50 dBm, the effect is obvious). Generally, dark current is very small and is basically in the uA and nA levels, in the field of optical communication, the dark current of a common Photodiode (Photodiode) is less than or equal to 10nA, and meanwhile, the dark current index can be used for judging whether a diode element is broken down or not and whether a wafer process has problems or not. As the temperature changes, the dark current of a Photodiode (photo diode) also changes with the temperature. Through a large number of engineering temperature data experiments, the dark current compensation power P of each stage can be seen_darkWill change as a second order polynomial function with temperature T, where FIG. 6 is a graph of the first stage LV1.K/C dark current power (dBm) versus temperature, where R²＝0.9983。

The best dark current compensation power P can be fitted by experimental data_darkThe formula for the variation with temperature T is as follows (calibration fit temperatures 25 deg.C, 45 deg.C and 65 deg.C, respectively):

P_dark＝a₃*T²+b₃*T+c₃

wherein, a₃、b₃、c₃Is a parameter of a second order polynomial function.

Temperature compensated probe power P_dBmThe calculation is as follows:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*Log10(ADC)*10+(a₂*T²+b₂*T+c₂))-dB2mw(a₃*T²+b₃*T+c₃))

the temperature simulation compensation system of the photoelectric detection device provided by the embodiment calculates the optical power according to the following method:

when the working temperature T is less than or equal to 25 ℃ and is in the first stage or the second stage, the dark current power is compensated, and the method comprises the following steps:

P_dBm＝mw2dB(dB2mw(K*Log10(ADC)*10+C)-dB2mw(a₃*T²+b₃*T+c₃))

when the working temperature T is less than or equal to 25 ℃ and is in the third stage to the sixth stage, compensation is not needed:

P_dBm＝K*Log10(ADC)*10+C

when the working temperature T is more than 25 ℃ and is in the first stage or the second stage, compensating the temperature and the dark current power:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*Log10(ADC)*10+(a₂*T²+b₂*T+c₂))-dB2mw(a₃*T²+b₃*T+c₃))

when the working temperature T is more than 25 ℃ and is in the third stage to the sixth stage, the temperature is compensated:

P_dBm＝(a₁*T²+b₁*T+c₁)*Log10(ADC)*10+(a₂*T²+b₂*T+c₂)

wherein a is₁、b₁、c₁、a₂、b₂、c₂And obtaining the lower linear working section (LV1.K/C, LV2.K/C, LV3.K/C, LV4.K/C, LV5.K/C and LV6.K/C) according to the electric performance by section fitting, wherein a₃、b₃、c₃Or obtaining the data according to the piecewise fitting of the working sections (LV1.K/C and LV2. K/C).

Through determination: under the ambient temperature of minus 5 ℃ to plus 65 ℃, the ultra-wide detection range of the power of a Photodiode (Photodiode) is beyond minus 60dBm to 20dBm and exceeds 75dB detection range; under the ambient temperature of minus 5 ℃ to plus 65 ℃, the error precision is less than 0.5dB in the range of 75dB power detected by a Photodiode (Photodiode) (when the detected power is less than minus 50dBm, the precision still meets the requirement through the dark current temperature related compensation technology).

Example 2 logarithmic photodetector System

The structure of the logarithmic photoelectric detection system provided by this embodiment is shown in fig. 7, and includes a logarithmic photoelectric detector and a temperature analog compensation system of a photoelectric detection device.

As shown in fig. 2, the logarithmic photodetector includes a photodiode, a logarithmic transimpedance amplifier (AD8304 chip), and an operational amplifier circuit (AMP (2)) connected in series. The logarithmic amplifier generally uses the middle section with good linear relation as the working section, and the linear relation between the output quantity at two ends and the optical power is deteriorated, so that the logarithmic amplifier is abandoned. In order to widen the operating range of the logarithmic photodetector, the low power segment or the high power segment outside the linear operating range is subjected to temperature compensation and/or dark current compensation. The detection accuracy can also be improved by temperature compensation and dark current compensation for the working range. In general, the working range can be widened and the precision can be improved at low cost.

The temperature simulation compensation system of the photoelectric detection device adopts a central processing unit and peripheral circuits, hardware of the temperature simulation compensation system consists of a high-speed micro control processor (MCU), a minimum power supply circuit unit of the processor and high-speed DA, AD, PWM and IO ports of the processor, and the hardware is a core part of a control, detection and acquisition circuit module.

The temperature analog compensation system of the photoelectric detection device reads the interface sampling ADC data of the logarithmic photoelectric detector through a high-speed micro control processor (MCU) to serve as output quantity. According to the ADC data sampled by the interface, the linear section where the ADC data is located is determined, and the slope K, the intercept C and/or the dark current compensation power P of the corresponding linear section are adopted_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power. The method specifically comprises the following steps:

under the condition of not considering the temperature change of a Photodiode (Photodiode) and the influence of dark current, 3 segments of LOG amplified detection data (3 segments respectively represent: LV1-1.K/C, LV1-2.K/C, LV1-3.K/C) can be obtained by segmenting the ADC2 and the ADC3, and the schematic diagram is shown in FIG. 8.

Linear fitting is respectively adopted for the three sections, wherein the linear fitting degree of LV1-2.K/C is good, namely the working section of general logarithmic photoelectric detection is shown in a schematic diagram in FIG. 9. In the lowest stage amplifying circuit LV1-1.K/C (-55dBm to-60 dBm), the sampling data presents nonlinear characteristics, and the sampling data is analyzed to be caused by dark current and change along with temperature.

The temperature analog compensation system of the photoelectric detection device acquires the output quantity of the logarithmic photoelectric detector, namely interface sampling ADC data, determines the linear section where the interface sampling ADC data is located according to the interface sampling ADC data, and compensates the power P by adopting the slope K, the intercept C and/or the dark current of the corresponding linear section_darkThe slope K, intercept C, and/or dark current compensation power P used for the parametric calculation linear fit of the second order function_darkAnd performing linear fitting on the output quantity of the photoelectric detector to obtain the detected optical power. The method comprises the following specific steps:

in the temperature simulation compensation system for a photo-detector device provided in this embodiment, a fitting power formula for each segment of a logarithmic photo-detector is as follows:

P_dBm＝K*ADC+C

and reading an ADC value corresponding to the PD from an AD interface of the MCU, and determining the section according to the range of the ADC value. After the K, C value of the section is compensated according to the working temperature, the optical power is calculated:

take the first stage (LV1.K/C) as an example: the curve of K value with temperature T is shown in FIG. 10, R²0.9902; the curve of C value with temperature T is shown in 11, R²＝0.987。

Through determination: under the ambient temperature of minus 5 ℃ to plus 65 ℃, the ultra-wide detection range of the power of a Photodiode (Photodiode) is beyond minus 60dBm to 20dBm and exceeds 75dB detection range; the formula for the variation of K, C values with temperature T can be derived by fitting a large number of experimental data as follows (calibration fitting temperatures of 25 deg.C, 45 deg.C and 65 deg.C, respectively):

K＝a₁*T²+b₁*T+c₁

C＝a₂*T²+b₂*T+c₂

wherein T is the working temperature, a₁、b₁、c₁、a₂、b₂、c₂Parameters for the second order polynomial function are determined by data fitting.

Through a large number of engineering temperature data experiments, the dark current compensation power P of each stage can be seen_darkWill change with a second order polynomial function with temperature T, wherein FIG. 12 is a first order LV1.K/C, dark current power (dBm) with temperature change curve R²＝0.9982。

The best dark current compensation power P can be fitted by experimental data_darkThe formula for the variation with temperature T is as follows (calibration fit temperatures 25 deg.C, 45 deg.C and 65 deg.C, respectively):

P_dark＝a₃*T²+b₃*T+c₃

wherein, a₃、b₃、c₃Is a parameter of a second order polynomial function.

Temperature compensated probe power P_dBmThe calculation is as follows:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*ADC+(a₂*T²+b₂*T+c₂))-dB2mw(a₃*T²+b₃*T+c₃))

the temperature simulation compensation system of the photoelectric detection device provided by the embodiment calculates the optical power according to the following method:

reading an ADC value of the corresponding PD from an AD interface of the MCU, and judging the size relation between the ADC value and the ADC2 and the ADC 3:

when ADC < ADC2, compensating dark current, when temperature working temperature T is less than or equal to 25 ℃, not needing to compensate temperature, including:

P_dBm＝mw2dB(dB2mw(K*ADC+C)-dB2mw(a₃*T²+b₃*T+c₃))

the working temperature T is more than 25 ℃ to compensate the temperature, and comprises the following components:

P_dBm＝mw2dB(dB2mw((a₁*T²+b₁*T+c₁)*ADC+(a₂*T²+b₂*T+c₂))-dB2mw(a₃*T²+b₃*T+c₃))

when ADC2 is not less than ADC3, the device is in a linear working section of the logarithmic power detection device, T is not less than 25 ℃, and the compensation is as follows:

P_dBm＝K*Log10(ADC)*10+C

the working temperature T is more than 25 ℃ to compensate the temperature, and comprises the following components:

P_dBm＝(a₁*T²+b₁*T+c₁)*OUTPUT+(a₂*T²+b₂*T+c₂)

when ADC3 < ADC, temperature compensation is required, as follows:

P_dBm＝(a₁*T²+b₁*T+c₁)*ADC+(a₂*T²+b₂*T+c₂)

wherein a is₁、b₁、c₁、a₂、b₂、c₂And obtaining by segment fitting according to the working segment (LV1-1.K/C, LV1-2.K/C, LV1-3. K/C).

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.