Extinction ratio measuring system and extinction ratio measuring method

Abstract

The invention discloses an extinction ratio measurement system and an extinction ratio measurement method, and relates to the technical field of optical module extinction ratio measurement. The transimpedance amplification circuit is connected with the optical module to be measured and used for monitoring the optical signal intensity of the optical module to be measured and obtaining a power monitoring voltage signal; decomposing the optical signal of the optical module to be tested to obtain a reference voltage signal and a test voltage signal; the linear output circuit is connected with the transimpedance amplification circuit and used for carrying out linear amplification on a difference value between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal; and the processing circuit is respectively connected with the transimpedance amplification circuit and the linear output circuit, and is used for determining the light modulation amplitude according to the ratio of the power monitoring voltage signal to the modulation amplitude voltage signal, and determining the extinction ratio of the optical module to be detected according to the light modulation amplitude and the light power corresponding to the power monitoring voltage signal. The measurement cost of the extinction ratio of the optical module can be reduced.

Description

Technical Field

[0001] This application relates to the technical field of extinction ratio measurement for optical modules, and particularly to an extinction ratio measurement system and an extinction ratio measurement method. Background Technique

[0002] In the related art, the extinction ratio test of an optical module is generally implemented based on the measurement of a DCA (Digital Communication Analyzer) high-speed signal oscilloscope. However, with the increasing production volume of optical modules, the cost of purchasing a DCA high-speed signal oscilloscope for the production line is getting higher and higher. Especially currently, with the upgrade of optical modules, such as the oscilloscope price for 1.6T optical modules and even for the next-generation 3.2T optical modules is more expensive, which will increase the test cost of optical modules. Summary of the Invention

[0003] The main purpose of this application is to provide an extinction ratio measurement system and an extinction ratio measurement method, aiming to solve the technical problem of high extinction ratio measurement cost in the related art.

[0004] To achieve the above object, this application proposes an extinction ratio measurement system, which includes:

[0005] The optical module to be measured;

[0006] A transimpedance amplifier circuit, connected to the optical module to be measured, for monitoring the optical signal intensity of the optical module to be measured to obtain a power monitoring voltage signal; and decomposing the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal;

[0007] A linear output circuit, connected to the transimpedance amplifier circuit, for linearly amplifying the difference between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal;

[0008] A processing circuit, respectively connected to the transimpedance amplifier circuit and the linear output circuit, for determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal, and determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

[0009] In an embodiment, the linear output circuit includes a resistor R1, a resistor R2, a resistor R3, a capacitor C1, and an operational amplifier chip U1;

[0010] One end of resistor R1 is connected to a transimpedance amplifier circuit, and the other end of resistor R1 is connected to the non-inverting input terminal of operational amplifier chip U1. One end of resistor R2 is connected to the transimpedance amplifier circuit, and the other end of resistor R2 is respectively connected to the inverting input terminal of operational amplifier chip U1, one end of resistor R3, and one end of capacitor C1. The output terminal of operational amplifier chip U1 is respectively connected to the other end of resistor R3, the other end of capacitor C1, and a processing circuit.

[0011] In one embodiment, the linear output circuit further includes a low-pass filtering unit;

[0012] The output terminal of operational amplifier chip U1 is connected to the processing circuit through the low-pass filtering unit; the low-pass filtering unit is used to suppress high-frequency noise to stabilize the output modulated amplitude voltage signal.

[0013] In one embodiment, the low-pass filtering unit includes resistor R4 and capacitor C2;

[0014] One end of resistor R4 is connected to the output terminal of operational amplifier chip U1, the other end of resistor R4 is respectively connected to one end of capacitor C2 and the processing circuit, and the other end of capacitor C2 is grounded.

[0015] In one embodiment, the processing circuit is specifically configured to determine the optical modulation amplitude according to the power monitoring voltage signal, the modulated amplitude voltage signal, and Equation 1; where Equation 1 is:

[0016]

[0017] Where OMA is the optical modulation amplitude, LOM is the voltage value of the modulated amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal.

[0018] In one embodiment, the processing circuit is further configured to determine the extinction ratio according to the optical modulation amplitude, the optical power corresponding to the power monitoring voltage signal, and Equation 2; where Equation 2 is:

[0019]

[0020] Where OER is the extinction ratio and power is the optical power corresponding to the power monitoring voltage signal.

[0021] In one embodiment, the optical module to be measured is a 1.6T optical module or a 3.2T optical module.

[0022] In addition, to achieve the above object, the present application also proposes an extinction ratio measurement method, which can be used in the extinction ratio measurement system as described above. The extinction ratio measurement method includes:

[0023] Monitoring the optical signal intensity of the optical module to be measured through a transimpedance amplifier circuit to obtain a power monitoring voltage signal, and decomposing the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal;

[0024] Linearly amplifying the difference between the reference voltage signal and the test voltage signal through a linear output circuit to obtain a modulation amplitude voltage signal;

[0025] The processing circuit determines the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal, and determines the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

[0026] In one embodiment, the step of determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal includes:

[0027] Determining the optical modulation amplitude according to the power monitoring voltage signal, the modulation amplitude voltage signal and calculation formula 1; where calculation formula 1 is:

[0028]

[0029] where OMA is the optical modulation amplitude, LOM is the voltage value of the modulation amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal.

[0030] In one embodiment, the step of determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal includes:

[0031] Determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude, the optical power and calculation formula 2; where calculation formula 2 is:

[0032]

[0033] where OER is the extinction ratio and power is the optical power.

[0034] One or more technical solutions proposed in this application have at least the following technical effects:

[0035] This application proposes an extinction ratio measurement system, which includes an optical module to be measured, a transimpedance amplifier circuit, a linear output circuit and a processing circuit. The optical signal output by the optical module to be measured can be processed by the transimpedance amplifier circuit to obtain a reference voltage signal, a test voltage signal and a power monitoring voltage signal; the linear output circuit linearly amplifies the difference between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal; thus, the processing circuit can determine the optical modulation amplitude according to the received power monitoring voltage signal and the modulation amplitude voltage signal, and calculate the extinction ratio of the optical module to be measured from the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

[0036] Through simple circuit designs and modular combinations such as a transimpedance amplifier circuit, a linear output circuit, and a processing circuit, the extinction ratio measurement of the optical module is achieved. Moreover, the transimpedance amplifier circuit and the linear output circuit can quickly process signals, and the processing circuit can calculate the extinction ratio of the optical module to be measured in real time according to the received signals, which can effectively ensure the test efficiency of the optical module and be applicable to large-scale production environments. Thus, it can effectively replace the solution of using an expensive DCA high-speed signal oscilloscope to measure the extinction ratio in the related technology, and significantly reduce the cost of measuring the extinction ratio of the optical module. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings herein are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0038] To more clearly illustrate the technical solutions in the embodiments of the present application or in the related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or the related technologies. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a schematic structural diagram of the first embodiment of the extinction ratio measurement system of the present application;

[0040] Figure 2 It is a detailed circuit schematic diagram of the linear output circuit of the present application;

[0041] Figure 3 It is a schematic flowchart provided by the first embodiment of the extinction ratio measurement method of the present application.

[0042] The implementation, functional features, and advantages of the present application will be further described in conjunction with the embodiments with reference to the drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] To better understand the technical solutions of the present application, the following will be described in detail in conjunction with the drawings of the specification and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0044] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of this application, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0045] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of this application, then such descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or the solution where A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0046] In the related art, the extinction ratio test of an optical module is generally realized based on the measurement of a DCA high-speed signal oscilloscope. However, with the increasing production volume of optical modules, the cost of purchasing a DCA high-speed signal oscilloscope for the production line is getting higher and higher. Especially with the continuous upgrade of optical modules, for example, the price of a DCA high-speed signal oscilloscope for 1.6T optical modules and even for the next-generation 3.2T optical modules is even more expensive, which will cause a sharp increase in the test cost of the optical module production line.

[0047] To solve this technical problem, this application proposes an extinction ratio measurement system. The extinction ratio measurement system includes an optical module under test, a transimpedance amplifier circuit, a linear output circuit, and a processing circuit. The optical signal output by the optical module under test can obtain a reference voltage signal, a test voltage signal, and a power monitoring voltage signal after being processed by the transimpedance amplifier circuit; the linear output circuit linearly amplifies the difference between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal; thus, the processing circuit can determine the optical modulation amplitude according to the received power monitoring voltage signal and the modulation amplitude voltage signal, and calculate the extinction ratio of the optical module under test from the optical power corresponding to the optical modulation amplitude and the power monitoring voltage signal.

[0048] Through simple circuit designs and modular structures such as a transimpedance amplifier circuit, a linear output circuit, and a processing circuit, the extinction ratio measurement of the optical module is realized. The transimpedance amplifier circuit and the linear output circuit can quickly process signals, and the processing circuit can also calculate the extinction ratio in real time according to the received signals, which can ensure the test efficiency of the optical module and is applicable to large-scale production environments. Therefore, it can effectively replace the solution of using an expensive DCA high-speed signal oscilloscope to measure the extinction ratio in related technologies, and can significantly reduce the test cost of the optical module.

[0049] The following will be described and introduced through multiple embodiments.

[0050] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of the first embodiment of the extinction ratio measurement system of the present application.

[0051] In this embodiment, the extinction ratio measurement system may include:

[0052] The optical module to be measured;

[0053] A transimpedance amplifier circuit, connected to the optical module to be measured, for monitoring the optical signal intensity of the optical module to be measured to obtain a power monitoring voltage signal; and decomposing the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal;

[0054] A linear output circuit, connected to the transimpedance amplifier circuit, for linearly amplifying the difference between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal;

[0055] A processing circuit, respectively connected to the transimpedance amplifier circuit and the linear output circuit, for determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal, and determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

[0056] Specifically, the optical module to be measured is the test object of this extinction ratio measurement system, usually a high-speed optical communication module. The transmitting end (TX end) of the optical module to be measured can output a modulated optical signal, which contains the modulation information to be measured, such as the change in the intensity of light (which can reflect the data transmission situation), etc.; the optical signal is usually a modulated light wave, which contains high level (logic "1") and low level (logic "0").

[0057] The transimpedance amplifier circuit is connected to the optical module under test, and can receive the optical signal output from the TX end of the optical module under test, and preliminarily process the optical signal to obtain a power monitoring voltage signal and a signal to be processed required by the linear output circuit (i.e., a reference voltage signal and a test voltage signal); the transimpedance amplifier circuit can adopt an integrated TIA (Trans-Impedance Amplifier) chip, such as a TIA chip with the model number IN5669TA, and multiple circuit units are integrated in the TIA (such as a photodiode, a power monitoring unit, a reference voltage unit, and a test voltage unit); among them, the photodiode can convert the optical signal output by the optical module under test into a photocurrent signal, and this photocurrent signal can be converted into a voltage signal (i.e., a power monitoring voltage signal) through the power monitoring unit, and this power monitoring voltage signal is in a proportional relationship with the optical power of the optical module under test. The RSSI pin of the TIA is used to output this power monitoring voltage signal. After obtaining the power monitoring voltage signal, the actual optical power corresponding to the power monitoring voltage signal can be determined by means of the proportional relationship formula between the power monitoring voltage signal and the optical power, or by querying the mapping form of "power monitoring voltage signal - optical power", etc.

[0058] The photocurrent signal can be expressed as the superposition of a DC component and an AC component; among them, the DC component is related to the low level of the optical signal and can reflect the static working state of the optical module; the AC component is the dynamic change part of the optical signal and reflects the peak modulation information of the optical signal, especially the change of the high level and the low level. Therefore, the AC component is related to the difference between the high level and the low level of the optical signal. To facilitate the accurate analysis and measurement of the extinction ratio of the optical module under test, it is necessary to decompose the photocurrent signal to determine the voltage information corresponding to the DC component and the AC component respectively. The reference voltage unit inside the TIA can output a corresponding reference voltage signal (denoted as VREF) according to the DC component of the photocurrent signal. VREF is usually a stable voltage level; the test voltage unit inside the TIA can extract the AC component from the photocurrent signal through an internal filtering and amplification module, etc., and convert it into a corresponding test voltage signal (denoted as VTEST). VTEST is generally a dynamic signal that changes with time; VREF and VTEST can be output to the linear output circuit through the reserved functional pins of the TIA chip for subsequent signal processing.

[0059] After receiving VREF and VTEST from the transimpedance amplifier circuit, the linear output circuit can linearly amplify the difference between VREF and VTEST, which can reflect the modulation amplitude state of the optical signal; after the amplification process, the linear output circuit can output a modulated amplitude voltage signal, which directly reflects the modulation amplitude of the optical signal and can be used as the key input information for subsequent calculation of the optical modulation amplitude and extinction ratio. In a feasible implementation manner, the above linear output circuit may include a resistor R1, a resistor R2, a resistor R3, a capacitor C1, and an operational amplifier chip U1.

[0060] Figure 2 is a detailed circuit schematic diagram of the linear output circuit, as Figure 2 shown, one end of the resistor R1 is connected to the transimpedance amplifier circuit, and the other end of the resistor R1 is connected to the non-inverting input terminal (port 1) of the operational amplifier chip U1. One end of the resistor R2 is connected to the transimpedance amplifier circuit, and the other end of the resistor R2 is respectively connected to the inverting input terminal (port 2) of the operational amplifier chip U1, one end of the resistor R3, and one end of the capacitor C1. The output terminal (port 3) of the operational amplifier chip U1 is respectively connected to the other end of the resistor R3, the other end of the capacitor C1, and the processing circuit. In the above circuit structure, VREF output by the TIA can be input to the inverting input terminal of the operational amplifier chip U1 through the resistor R2, and VTEST output by the TIA is input to the non-inverting input terminal of the operational amplifier chip U1 through the resistor R1 for the operational amplifier chip U1 to perform linear amplification processing. In as Figure 2 shown in the circuit structure, the other end of the resistor R1 is also connected to one end of the resistor R5, and the other end of the resistor R5 is grounded; at the same time, the operational amplifier chip U1 is also connected to a 3.3V working power supply through the power supply port (port 4) and grounded through the grounding port (port 5); the resistor R5 and the resistor R1 can form a voltage dividing network to ensure that the operational amplifier chip U1 can always work in the linear region to obtain a more accurate modulated amplitude voltage signal output.

[0061] In addition, the linear output circuit may further include a low-pass filtering unit, and the output terminal of the operational amplifier chip U1 may be connected to the processing circuit through the low-pass filtering unit; the low-pass filtering unit is used to suppress high-frequency noise to stabilize the output modulated amplitude voltage signal and avoid the influence of noise interference on the subsequent extinction ratio calculation result. As Figure 2 shown, the low-pass filtering unit may include a resistor R4 and a capacitor C2; one end of the resistor R4 is connected to the output terminal of the operational amplifier chip U1, the other end of the resistor R4 is respectively connected to one end of the capacitor C2 and the processing circuit, and the other end of the capacitor C2 is grounded.

[0062] After receiving the power monitoring voltage signal output by the transimpedance amplifier circuit and the modulation amplitude voltage signal processed by the linear output circuit, the processing circuit can perform further arithmetic processing to obtain the extinction ratio corresponding to the optical module to be measured. In practical applications, the processing circuit part can be a processor chip with computing functions, or a computing device such as a host computer for real-time computing; the processing circuit can determine the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal. In a feasible implementation manner, the processing circuit can specifically determine the optical modulation amplitude according to the power monitoring voltage signal, the modulation amplitude voltage signal, and calculation formula 1; where, calculation formula 1 is:

[0063]

[0064] Among them, OMA is the optical modulation amplitude, LOM is the voltage value of the modulation amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal; in the above calculation formula 1, the ratio of LOM to RSSI can reflect the signal modulation depth, and it needs to be converted to logarithmic units (dBm) through logarithmic operations to match the optical communication standard.

[0065] The processing circuit can determine the optical power power corresponding to the power monitoring voltage signal (i.e., RSSI) through a preset proportional relationship formula between the power monitoring voltage signal and the optical power, or a "power monitoring voltage signal - optical power" mapping form, etc.; then, using the determined optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal, the extinction ratio of the optical module to be measured is determined. In a feasible implementation manner, the processing circuit can also determine the extinction ratio according to the optical modulation amplitude, the optical power corresponding to the power monitoring voltage signal, and calculation formula 2; where, calculation formula 2 is:

[0066]

[0067] Among them, OER is the extinction ratio, and power is the optical power corresponding to the power monitoring voltage signal.

[0068] Substituting the OMA obtained from calculation formula 1 and the power corresponding to the power monitoring voltage signal into the above calculation formula 2, the extinction ratio OER corresponding to the optical module to be measured can be solved. OER can be used for the quality evaluation of the optical module. Generally, a higher OER value means a higher contrast of the optical signal and better signal quality output by the optical module.

[0069] It can be seen that the above extinction ratio measurement system can monitor and decompose optical signals through a transimpedance amplifier circuit, extract the modulation depth through a linear output circuit, and calculate OER in real time through a processing circuit. The structures of the transimpedance amplifier circuit and the linear output circuit are simple and easy to obtain, and can achieve low-cost and high-efficiency extinction ratio measurement to replace the DCA high-speed signal oscilloscope for extinction ratio measurement.

[0070] In addition, the optical module to be measured described above can be a 1.6T optical module or a 3.2T optical module. The 1.6T optical module and the 3.2T optical module have a high transmission rate, and the corresponding DCA high-speed signal oscilloscope for testing is also more expensive. Using the extinction ratio measurement system provided by the embodiments of the present application to measure the extinction ratio of the 1.6T optical module or the 3.2T optical module can significantly reduce the test cost of the high-speed optical module.

[0071] In addition, the transimpedance amplifier circuit mentioned above can use a TIA chip that supports multi-channel parallelism. In this way, the TIA can access the optical signals of multiple optical modules to be measured at the same time, and a linear output circuit is configured for each output of the TIA. Thus, the monitoring and extinction ratio measurement of multiple optical signals can be realized.

[0072] It is not difficult to understand that the embodiments of the present application realize the measurement of the extinction ratio of the optical module through simple circuit designs and modular structures such as the transimpedance amplifier circuit, the linear output circuit, and the processing circuit. The transimpedance amplifier circuit and the linear output circuit can quickly process signals, and the processing circuit can also calculate the extinction ratio in real time according to the received signals, which can ensure the test efficiency of the optical module and is applicable to large-scale production environments. Thus, it can effectively replace the solution of using an expensive DCA high-speed signal oscilloscope to measure the extinction ratio in the related art and can significantly reduce the test cost of the optical module.

[0073] Furthermore, the embodiments of the present application provide an extinction ratio measurement method, which can be used in the extinction ratio measurement system described in the foregoing embodiments. Refer to Figure 3 , Figure 3 shows a schematic flowchart of the first embodiment of the extinction ratio measurement method of the present application.

[0074] In this embodiment, the extinction ratio measurement method may include steps S100 to S300:

[0075] Step S100: Monitor the optical signal intensity of the optical module to be measured through a transimpedance amplifier circuit to obtain a power monitoring voltage signal, and decompose the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal.

[0076] Step S200: Linearly amplify the difference between the reference voltage signal and the test voltage signal through a linear output circuit to obtain a modulation amplitude voltage signal.

[0077] Step S300: Determine the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal through a processing circuit, and determine the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

[0078] In a feasible implementation manner, the step of determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal may specifically include:

[0079] Determine the optical modulation amplitude according to the power monitoring voltage signal, the modulation amplitude voltage signal and Equation 1; wherein, Equation 1 is:

[0080]

[0081] wherein, OMA is the optical modulation amplitude, LOM is the voltage value of the modulation amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal.

[0082] The step of determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal may specifically include:

[0083] Determine the extinction ratio of the optical module to be measured according to the optical modulation amplitude, the optical power and Equation 2; wherein, Equation 2 is:

[0084]

[0085] wherein, OER is the extinction ratio and power is the optical power.

[0086] It should be noted that for more implementation details in the specific implementation manner of the extinction ratio measurement method steps in this embodiment, reference can be made to the description of the specific implementation manner of the extinction ratio measurement system in the foregoing embodiment. For the sake of brevity of the specification, it will not be repeated here.

[0087] The foregoing are only some embodiments of the present application, and thus do not limit the patent scope of the present application. Any equivalent structural transformation made under the technical concept of the present application by using the content of the specification and drawings of the present application, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present application.

Claims

1. An extinction ratio measurement system, characterized in that, The extinction ratio measurement system includes: An optical module to be measured; A transimpedance amplifier circuit, connected to the optical module to be measured, for monitoring the optical signal intensity of the optical module to be measured to obtain a power monitoring voltage signal; and decomposing the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal; A linear output circuit, connected to the transimpedance amplifier circuit, for linearly amplifying the difference between the reference voltage signal and the test voltage signal to obtain a modulation amplitude voltage signal; A processing circuit, respectively connected to the transimpedance amplifier circuit and the linear output circuit, for determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal and the modulation amplitude voltage signal, and determining the extinction ratio of the optical module to be measured according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

2. The extinction ratio measurement system according to claim 1, wherein The linear output circuit includes a resistor R1, a resistor R2, a resistor R3, a capacitor C1, and an operational amplifier chip U1; One end of the resistor R1 is connected to the transimpedance amplifier circuit, the other end of the resistor R1 is connected to the non-inverting input terminal of the operational amplifier chip U1, one end of the resistor R2 is connected to the transimpedance amplifier circuit, and the other end of the resistor R2 is respectively connected to the inverting input terminal of the operational amplifier chip U1, one end of the resistor R3, and one end of the capacitor C1. The output terminal of the operational amplifier chip U1 is respectively connected to the other end of the resistor R3, the other end of the capacitor C1, and the processing circuit.

3. The extinction ratio measurement system according to claim 2, wherein The linear output circuit further includes a low-pass filtering unit; The output terminal of the operational amplifier chip U1 is connected to the processing circuit through the low-pass filtering unit; the low-pass filtering unit is used to suppress high-frequency noise to stably output the modulation amplitude voltage signal.

4. The extinction ratio measurement system according to claim 3, wherein The low-pass filtering unit includes a resistor R4 and a capacitor C2; One end of the resistor R4 is connected to the output terminal of the operational amplifier chip U1, the other end of the resistor R4 is respectively connected to one end of the capacitor C2 and the processing circuit, and the other end of the capacitor C2 is grounded.

5. The extinction ratio measurement system according to claim 1, characterized in that The processing circuit is specifically used to determine the optical modulation amplitude according to the power monitoring voltage signal, the modulation amplitude voltage signal, and calculation formula 1; wherein, the calculation formula 1 is: Where OMA is the optical modulation amplitude, LOM is the voltage value of the modulation amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal.

6. The extinction ratio measurement system according to claim 5, characterized in that, The processing circuit is further used to determine the extinction ratio according to the optical modulation amplitude, the optical power corresponding to the power monitoring voltage signal, and calculation formula 2; wherein, the calculation formula 2 is: Where OER is the extinction ratio and power is the optical power corresponding to the power monitoring voltage signal.

7. The extinction ratio measurement system according to any one of claims 1 to 6, characterized in that The optical module to be measured is a 1.6T optical module or a 3.2T optical module.

8. A method for measuring extinction ratio, characterized in that, For the extinction ratio measurement system according to any one of claims 1 to 7, the extinction ratio measurement method includes: Monitoring the optical signal intensity of the optical module to be measured through a transimpedance amplifier circuit to obtain a power monitoring voltage signal, and decomposing the optical signal of the optical module to be measured to obtain a reference voltage signal and a test voltage signal; The difference between the reference voltage signal and the test voltage signal is linearly amplified by a linear output circuit to obtain a modulated amplitude voltage signal; A processing circuit determines the optical modulation amplitude according to the ratio of the power monitoring voltage signal to the modulated amplitude voltage signal, and determines the extinction ratio of the optical module under test according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal.

9. The extinction ratio measurement method according to claim 8, characterized in that The step of determining the optical modulation amplitude according to the ratio of the power monitoring voltage signal to the modulated amplitude voltage signal includes: Determining the optical modulation amplitude according to the power monitoring voltage signal, the modulated amplitude voltage signal and Equation 1; wherein, Equation 1 is: where OMA is the optical modulation amplitude, LOM is the voltage value of the modulated amplitude voltage signal, and RSSI is the voltage value of the power monitoring voltage signal.

10. The extinction ratio measurement method according to claim 9, characterized in that, The step of determining the extinction ratio of the optical module under test according to the optical modulation amplitude and the optical power corresponding to the power monitoring voltage signal includes: Determining the extinction ratio of the optical module under test according to the optical modulation amplitude, the optical power and Equation 2; wherein, Equation 2 is: where OER is the extinction ratio and power is the optical power.

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