CN104682193A

CN104682193A - Method and device for generating temperature lookup table of optical module

Info

Publication number: CN104682193A
Application number: CN201510135047.3A
Authority: CN
Inventors: 陈彪
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2013-01-06
Filing date: 2013-01-06
Publication date: 2015-06-03
Anticipated expiration: 2033-01-06
Also published as: CN104682193B

Abstract

The invention discloses a method and device for generating a temperature lookup table of an optical module. The method comprises the following steps: adjusting the optical power and extinction ratio output by a test optical module to preset target values to obtain test temperature values, test bias current set register values and test modulation current set register values of the test optical module at temperature points; performing normalization treatment on the obtained current values to obtain a current normalization slope parameter in a temperature range formed by the various temperature points; adjusting the optical power and extinction ratio output by the optical module to be applied to the preset target values to obtain working temperature values, bias current set register values and modulation current set register values of the optical module to be applied in a normal-temperature environment; and combining with the pre-obtained current normalization slope parameter to generate the current temperature lookup table of the optical module to be applied, and writing the generated current temperature lookup table into the optical module to be applied. By applying the invention, the efficiency of generating the temperature lookup table of the optical module can be improved.

Description

Method and device for generating optical module temperature lookup table

The application is a divisional application of a Chinese invention patent application 201310003863.X, entitled "method and device for generating a temperature lookup table of an optical module", which is proposed in 2013, 01, month and 06.

Technical Field

The present invention relates to optical communication technologies, and in particular, to a method and an apparatus for generating an optical module temperature lookup table.

Background

In the current domestic market and international market, the optical fiber communication direction with high bandwidth, high speed and multiple service fusion is already applied; among The numerous solutions, The emergence of Fiber To The Home (FTTH) is considered to be The ultimate solution for broadband access, and The domestic market has been widely applied.

The optical module is used as a core component of FTTH in an optical fiber communication system, the stability of the overall performance of the optical module is directly related to the performance stability of the optical fiber communication system, and the optical port performance of the transmitting end of the optical module, namely the quality of a transmitted optical signal, is also an important factor influencing the performance stability of the optical fiber communication system.

In the parameters of the quality of optical signals emitted by an optical port of an emitting end of an optical module, the quality of an eye pattern is mainly considered, wherein the main factors influencing the quality of the eye pattern are average optical power and extinction ratio, the average optical power and the extinction ratio are determined by the magnitude of bias current and modulation current provided by a laser driving chip in the optical module to a laser, and the larger the bias current is, the larger the average optical power is; when the average optical power is fixed, the larger the modulation current is, the larger the extinction ratio is; on the basis, because the laser is a device with temperature characteristics, the temperature characteristics of the device need to be considered, and for a fixed bias current and a fixed modulation current, when the temperature is reduced, the optical power is increased, and the extinction ratio is reduced; as the temperature increases, the optical power decreases and the extinction ratio increases.

In practical application, the optical module needs to be kept in a working temperature range, for example, the temperature range of commercial grade application is 0-70 ℃, and the temperature range of industrial grade application is-40-85 ℃. If the optical interface parameters of the transmitting end of the optical module are unstable, for example, the fluctuation of the optical eye diagram parameters is large, the receiving end can not recognize, and thus the communication is interrupted.

In practical application, in order to stabilize optical interface parameters of an optical module transmitting end, the optical module transmitting end generally adopts closed-loop Control, an Automatic Power Control (APC) loop is introduced into an optical module and used for adjusting a laser diode and a backlight diode in a bias current Control circuit, the APC loop introduces a negative feedback quantity into the bias current Control circuit of the transmitting end, and generates a feedback backlight current by coupling optical power emitted by a part of the laser diode with the backlight diode close to the laser diode, so that the APC loop adjusts the bias current output to the light emitting diode according to the feedback current and the bias current after comparing with a set reference value, and further stabilizes average optical power.

Theoretically, the backlight diode has no temperature characteristic, that is, as long as the light emission of the laser diode is constant and the coupling coefficient between the laser diode and the backlight diode is constant, the feedback current (bias current) provided by the backlight diode to the APC loop is constant, but in practical applications, a Transmitter Optical Subassembly (TOSA) that packages the laser diode and the backlight diode is affected by temperature, when the laser diode emits constant Optical power, if the temperature changes, the bias current output by the backlight diode also changes, and the change of the bias current affects the Optical power emitted by the laser diode. Therefore, when the environmental temperature of the APC loop changes, the optical power emitted by the optical module cannot be stabilized at a set value; if the average optical power varies, the extinction ratio will also vary, and the effect of modulating the current will also be affected by the temperature variation.

In practical application, in the APC loop, the modulation current input to the laser diode needs to be controlled according to the temperature of the emitting end of the optical module, so that the laser diode emits an optical signal with constant power. Therefore, in the prior art, in the software of the optical module, an optical module temperature lookup table is defined, and an offset current (APCset) value and a modulation current (MODset) value in the optical module are compensated according to an actual measurement temperature of a Micro Control Unit (MCU) including a temperature sensor, that is, the APCset and the MODset are adjusted according to a temperature change, so as to compensate the optical power and the extinction ratio, and stabilize the optical power and the extinction ratio of the optical signal output by the optical module. Wherein,

the APCset and the MODset respectively correspond to an independent optical module temperature lookup table, when the MCU monitors that the temperature changes, APCset and MODset values corresponding to the current temperature are searched in the preset optical module temperature lookup table according to the current temperature monitored by the MCU, and the searched values are respectively used as the current APCset and MODset values to control the laser diode, so that the optical signal quality of an optical module transmitting end is stabilized.

The existing method for generating an optical module temperature lookup table is to select a plurality of working temperature points according to the working temperature range of each optical module, record the temperature monitored by an MCU including a temperature sensor at each working temperature point, adjust the bias current and the modulation current of a laser diode so that the optical power and the extinction ratio of an optical signal emitted by the laser diode simultaneously satisfy preset values, write the monitoring temperature corresponding to the working temperature point, and the bias current and the modulation current setting register value corresponding to the working temperature point into the optical module temperature lookup table, obtain the bias current and the modulation current setting register value corresponding to each working temperature point according to the same manner, and write the bias current and the modulation current setting register value into the optical module temperature lookup table. Therefore, in the subsequent work of the optical module, the optical module temperature lookup table is searched according to the temperature monitored by the MCU, and the corresponding bias current and modulation current setting register value are obtained and used as the control parameter of the laser diode, so that the optical power and the extinction ratio output by the laser diode are constant, and the stability of the optical fiber communication system is improved.

As can be seen from the above, in the conventional method for generating an optical module temperature lookup table, a test within a working temperature range needs to be performed on each optical module to determine a modulation current and a bias current setting value corresponding to a correction point in subsequent work, a high-low temperature box or a wind gun is usually adopted to adjust the temperature of the optical module to each working temperature point, and time is required from temperature rise/decrease to stable temperature of the optical module.

Disclosure of Invention

The embodiment of the invention provides a method for generating an optical module temperature lookup table, which improves the efficiency of generating the optical module temperature lookup table.

The embodiment of the invention also provides a device for generating the optical module temperature lookup table, which improves the efficiency of generating the optical module temperature lookup table.

According to an aspect of the present invention, there is provided a method for generating a temperature lookup table of a light module, comprising:

the method comprises the steps of pre-dividing the environment temperature into a plurality of temperature points, adjusting the optical power output by a testing optical module to a preset target optical power at each temperature point, and obtaining a testing temperature value of the testing optical module at the temperature point and a testing bias current setting register value;

adjusting the extinction ratio output by the test optical module to a preset target extinction ratio, and acquiring a test modulation current setting register value of the test optical module at each temperature point;

normalizing the obtained test bias current setting register value to obtain a bias current normalized slope parameter of a temperature interval formed by each temperature point; normalizing the obtained test modulation current setting register value to obtain a temperature interval modulation current normalization slope parameter formed by each temperature point;

adjusting the optical power output by the optical module to be applied to a preset target optical power, adjusting the output extinction ratio to a preset target extinction ratio, and respectively obtaining a working temperature value, a bias current setting register value and a modulation current setting register value of the optical module to be applied in a normal temperature environment;

according to the obtained working temperature value and the bias current setting register value, and in combination with a bias current normalization slope parameter obtained in advance, generating a bias current temperature lookup table of the optical module to be applied; and generating a modulation current temperature lookup table of the optical module to be applied according to the acquired working temperature value and the modulation current setting register value and by combining a modulation current normalization slope parameter acquired in advance, and writing the generated bias current temperature lookup table and the generated modulation current temperature lookup table into the optical module to be applied.

The step of normalizing the obtained test bias current setting register value to obtain the bias current normalized slope parameter of the temperature interval formed by each temperature point comprises the following steps:

forming a corresponding temperature interval according to each divided temperature point;

acquiring a test bias current setting register value of a preset temperature point;

obtaining a difference value of a test temperature value corresponding to each temperature point interval;

obtaining the difference value of the test bias current setting register value corresponding to each temperature point interval;

and for each temperature point interval, dividing the difference value of the test bias current setting register value of the temperature point interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test bias current setting register value of the preset temperature point to obtain the bias current normalized slope parameter of the temperature interval.

The formula for obtaining the normalized slope parameter of the bias current is as follows:

in the formula,

k_bnormalizing the slope parameter for the bias current;

I_busetting a register value for the test bias current corresponding to the upper limit temperature of the temperature point interval;

I_bdsetting a register value for the test bias current corresponding to the lower limit temperature of the temperature point interval;

T_uthe temperature is a test temperature value corresponding to the upper limit temperature of the temperature point interval;

T_dthe temperature is a test temperature value corresponding to the lower limit temperature of the temperature point interval;

I_bcthe register value is set for the test bias current at the preset temperature point.

The step of normalizing the obtained test modulation current setting register value to obtain the temperature interval modulation current normalization slope parameter formed by each temperature point comprises the following steps:

acquiring a test modulation current setting register value of a preset temperature point;

obtaining the difference value of the test modulation current setting register value corresponding to each temperature point interval;

and for each temperature point interval, dividing the difference value of the test modulation current setting register value of the temperature point interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test modulation current setting register value of the preset temperature point to obtain the modulation current normalized slope parameter of the temperature interval.

The formula for obtaining the modulation current normalization slope parameter is as follows:

in the formula,

k_mnormalizing the slope parameter for the modulated current;

I_musetting a register value for the test modulation current corresponding to the upper limit temperature of the temperature point interval;

I_mdsetting a register value for the test modulation current corresponding to the lower limit temperature of the temperature point interval;

I_mcsetting a register value for the test modulation current of the preset temperature point.

After obtaining the bias current normalized slope parameter and the modulation current normalized slope parameter of the temperature interval formed by each temperature point, the method further comprises the following steps:

and constructing a mapping relation between the temperature point and the bias current normalized slope parameter, and constructing a mapping relation between the temperature point and the modulation current normalized slope parameter.

The generating of the bias current temperature lookup table of the optical module to be applied according to the obtained working temperature value and the bias current setting register value and by combining a bias current normalization slope parameter obtained in advance comprises the following steps:

inquiring a bias current normalized slope parameter of a temperature interval formed by each temperature point obtained in advance, and obtaining a bias current normalized slope value corresponding to the working temperature value;

calculating bias current setting register values of other temperature points in the temperature point interval according to the slope value and the bias current setting register value;

and calculating the bias current setting register value of each temperature point in the adjacent temperature point interval according to the bias current setting register value corresponding to the upper and lower limit temperature points of the temperature point interval and the bias current normalized slope parameter of the adjacent temperature point interval, until the bias current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a bias current temperature lookup table.

The formula for calculating the bias current setting register values of other temperature points in the temperature point interval is as follows:

I_bt＝I_bw-k_b×(T_w-T_t)×I_bc

in the formula,

I_btat other working temperatures T in the interval of the temperature points corresponding to the working temperatures_tSetting a register value by the bias current;

I_bwsetting a register value for the bias current corresponding to the working temperature;

k_bnormalizing slope parameters for the bias current in a temperature point interval corresponding to the working temperature;

T_wis the working temperature value;

The formula for calculating the bias current setting register value of each temperature point in the adjacent temperature point interval is as follows:

I_bt'＝I_bwu-k_b'×(T_w'-T_t')×I_bc

in the formula,

I_bt'for the internal working temperature T of the interval of adjacent temperature points_t'Setting a register value by the bias current;

I_bwusetting a register value for a bias current corresponding to the intersection temperature of a temperature point interval corresponding to the working temperature and an adjacent temperature point interval;

k_b'normalizing slope parameters for bias currents in adjacent temperature point intervals;

T_w'the intersection temperature value is obtained;

establishing a coordinate system of temperature and bias current setting register values, taking the temperature as an abscissa, the bias current setting register values as an ordinate, the bias current setting register values corresponding to the working temperature values as a base point, and the bias current normalization slope values corresponding to the working temperature values as a slope, and establishing a temperature point interval straight line corresponding to the working temperature values;

and acquiring bias current setting register values corresponding to upper and lower limit temperature points of the constructed straight line, constructing the straight line of the adjacent temperature point intervals by taking a bias current normalized slope value corresponding to the adjacent temperature point intervals as a slope, and generating a bias current temperature lookup table represented by a coordinate system.

The generating of the temperature interval modulation current temperature lookup table of the optical module to be applied by combining the modulation current normalization slope parameter obtained in advance according to the obtained working temperature value and the modulation current setting register value comprises:

inquiring a temperature interval modulation current normalization slope parameter formed by each temperature point obtained in advance, and obtaining a modulation current normalization slope value corresponding to the working temperature value;

calculating the modulation current setting register values of other temperature points in the temperature point interval according to the slope value and the modulation current setting register value;

and calculating the modulation current setting register value of each temperature point in the adjacent temperature point interval according to the modulation current setting register value corresponding to the upper and lower limit temperature points of the temperature point interval and the modulation current normalization slope parameter of the adjacent temperature point interval, until the modulation current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a modulation current temperature lookup table.

The formula for calculating the modulation current setting register values of other temperature points in the temperature point interval is as follows:

I_mt＝I_mw-k_m×(T_w-T_t)×I_mc

in the formula,

I_mtat other working temperatures T in the interval of the temperature points corresponding to the working temperatures_tSetting a register value by the modulation current;

I_mwsetting a register value for the modulation current corresponding to the working temperature;

k_mnormalizing slope parameters for the modulation current of a temperature point interval corresponding to the working temperature;

T_wis the working temperature value;

The formula for calculating the modulation current setting register value of each temperature point in the adjacent temperature point interval is as follows:

I_mt'＝I_mwu-k_m'×(T_w'-T_t')×I_mc

in the formula,

I_mt'for the internal working temperature T of the interval of adjacent temperature points_t'Setting a register value by the modulation current;

I_mwusetting a register value for a modulation current corresponding to the intersection temperature of a temperature point interval corresponding to the working temperature and an adjacent temperature point interval;

k_m'normalizing slope parameters for modulation current of adjacent temperature point intervals;

T_w'the intersection temperature value is obtained;

I_mcto presetThe test modulation current at the temperature point sets the register value.

An apparatus to generate a light module temperature lookup table, the apparatus comprising: a test bias current acquisition module, a test modulation current acquisition module, a normalization processing module, an application optical module current acquisition module and a temperature lookup table generation module, wherein,

the device comprises a test bias current acquisition module, a bias current setting register module and a control module, wherein the test bias current acquisition module is used for dividing the environment temperature into a plurality of temperature points in advance, adjusting the optical power output by the test optical module to the preset target optical power at each temperature point, and acquiring the test temperature value of the test optical module at the temperature point and the test bias current setting register value;

the test modulation current acquisition module is used for adjusting the extinction ratio output by the test optical module to a preset target extinction ratio and acquiring the test modulation current setting register value of the test optical module at each temperature point;

the normalization processing module is used for performing normalization processing on the obtained test bias current setting register value to obtain a bias current normalization slope parameter of a temperature interval formed by each temperature point; normalizing the obtained test modulation current setting register value to obtain a temperature interval modulation current normalization slope parameter formed by each temperature point;

the application optical module current acquisition module is used for adjusting the optical power output by the optical module to be applied to a preset target optical power, adjusting the output extinction ratio to a preset target extinction ratio, and respectively acquiring a working temperature value, a bias current setting register value and a modulation current setting register value of the optical module to be applied in a normal temperature environment;

the temperature lookup table generation module is used for setting a register value according to the acquired working temperature value and the bias current and generating a bias current temperature lookup table of the optical module to be applied by combining a bias current normalization slope parameter acquired in advance; and generating a modulation current temperature lookup table of the optical module to be applied according to the acquired working temperature value and the modulation current setting register value and by combining a modulation current normalization slope parameter acquired in advance, and writing the generated bias current temperature lookup table and the generated modulation current temperature lookup table into the optical module to be applied.

Preferably, the test bias current obtaining module includes: a temperature interval dividing unit, a test temperature difference value calculating unit, a test bias current difference value calculating unit, a bias current normalization slope calculating unit, a test modulation current difference value calculating unit and a modulation current normalization slope calculating unit, wherein,

the temperature interval dividing unit is used for forming corresponding temperature intervals according to the divided temperature points;

the test temperature difference calculation unit is used for acquiring the difference of the test temperature values corresponding to each temperature point interval;

the test bias current difference value calculation unit is used for setting a register value according to the obtained test bias current of the set temperature point and obtaining the difference value of the test bias current setting register value corresponding to each temperature point interval;

the bias current normalization slope calculation unit is used for dividing the difference value of the test bias current setting register value of each temperature point interval by the difference value of the test temperature value and multiplying the difference value by the reciprocal of the test bias current setting register value of the preset temperature point to obtain a bias current normalization slope parameter of the temperature interval;

the test modulation current difference value calculation unit is used for setting a register value according to the obtained test modulation current of the preset temperature point and obtaining the difference value of the test modulation current setting register value corresponding to each temperature point interval;

and the modulation current normalization slope calculation unit is used for dividing the difference value of the test modulation current setting register value of the temperature point interval by the difference value of the test temperature value aiming at each temperature point interval, and multiplying the difference value by the reciprocal of the test modulation current setting register value of the preset temperature point to obtain the modulation current normalization slope parameter of the temperature interval.

Preferably, the temperature lookup table generation module includes: a bias current normalization slope obtaining unit, a bias current setting register value obtaining unit, a bias current temperature lookup table generating unit, a modulation current normalization slope obtaining unit, a modulation current setting register value obtaining unit, and a modulation current temperature lookup table generating unit,

the bias current normalization slope obtaining unit is used for inquiring the bias current normalization slope calculating unit and obtaining a bias current normalization slope value corresponding to the working temperature value;

the bias current setting register value acquisition unit is used for calculating bias current setting register values of other temperature points in the temperature point interval according to the acquired slope value and the bias current setting register value corresponding to the working temperature;

the bias current temperature lookup table generating unit is used for calculating the bias current setting register value of each temperature point in the adjacent temperature point interval according to the bias current setting register value corresponding to the upper limit temperature point and the lower limit temperature point of the temperature point interval and the bias current normalization slope parameter of the adjacent temperature point interval, until the bias current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a bias current temperature lookup table;

the modulation current normalization slope obtaining unit is used for inquiring the modulation current normalization slope calculating unit and obtaining a modulation current normalization slope value corresponding to the working temperature value;

a modulation current setting register value obtaining unit, configured to calculate modulation current setting register values of other temperature points in the temperature point interval according to the obtained slope value and a modulation current setting register value corresponding to the operating temperature;

and the modulation current temperature lookup table generating unit is used for calculating the modulation current setting register value of each temperature point in the adjacent temperature point interval according to the modulation current setting register value corresponding to the upper limit temperature point and the lower limit temperature point of the temperature point interval and the modulation current normalization slope parameter of the adjacent temperature point interval, until the modulation current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a modulation current temperature lookup table.

As can be seen from the above, the method and apparatus for generating an optical module temperature lookup table according to the embodiment of the present invention include: the method comprises the steps of pre-dividing the environment temperature into a plurality of temperature points, adjusting the optical power output by a testing optical module to a preset target optical power at each temperature point, and obtaining a testing temperature value of the testing optical module at the temperature point and a testing bias current setting register value; adjusting the extinction ratio output by the test optical module to a preset target extinction ratio, and acquiring a test modulation current setting register value of the test optical module at each temperature point; normalizing the obtained test bias current setting register value to obtain a bias current normalized slope parameter of a temperature interval formed by each temperature point; normalizing the obtained test modulation current setting register value to obtain a temperature interval modulation current normalization slope parameter formed by each temperature point; adjusting the optical power output by the optical module to be applied to a preset target optical power, adjusting the output extinction ratio to a preset target extinction ratio, and respectively obtaining a working temperature value, a bias current setting register value and a modulation current setting register value of the optical module to be applied in a normal temperature environment; according to the obtained working temperature value and the bias current setting register value, and in combination with a bias current normalization slope parameter obtained in advance, generating a bias current temperature lookup table of the optical module to be applied; and generating a modulation current temperature lookup table of the optical module to be applied according to the acquired working temperature value and the modulation current setting register value and by combining a modulation current normalization slope parameter acquired in advance, and writing the generated bias current temperature lookup table and the generated modulation current temperature lookup table into the optical module to be applied. Therefore, each optical module does not need to be tested within the working temperature range, the efficiency of generating the optical module temperature lookup table is improved, and the time required for generating the optical module temperature lookup table is shortened.

Drawings

FIG. 1 is a schematic diagram of an APC loop control circuit according to the embodiment of the present invention.

Fig. 2 is a schematic diagram of a bias current, an output optical power and a loading voltage of a laser triode according to an embodiment of the invention.

Fig. 3 is a schematic diagram of modulation characteristics of a laser triode according to an embodiment of the invention.

Fig. 4 is a flowchart illustrating a method for generating a temperature lookup table of an optical module according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating normalized slope parameters according to an embodiment of the present invention.

Fig. 6 is a schematic structural diagram of an apparatus for generating an optical module temperature lookup table according to an embodiment 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 will be described in further detail below with reference to the accompanying drawings by way of examples of preferred embodiments. It should be noted, however, that the numerous details set forth in the description are merely for the purpose of providing the reader with a thorough understanding of one or more aspects of the present invention, which may be practiced without these specific details.

As used in this application, the terms "module," "system," and the like are intended to include a computer-related entity, such as but not limited to hardware, firmware, a combination of hardware and software, or software in execution. For example, a module may be, but is not limited to: a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. For example, an application running on a computing device and the computing device may both be a module. One or more modules may reside within a process and/or thread of execution and a module may be localized on one computer and/or distributed between two or more computers.

In the existing method for generating the optical module temperature lookup table, a test within a working temperature range needs to be performed on each optical module under the conditions of preset optical power and extinction ratio so as to determine subsequent modulation current and bias current set values, the required time is long, and the efficiency of generating the optical module temperature lookup table is low.

In the embodiment of the invention, a certain number of optical module samples are tested in a working temperature range in advance, each bias current setting register value and modulation current setting register value under the preset optical power and extinction ratio are obtained, normalization processing is carried out, an optical module testing temperature lookup table containing the mapping relation between the working temperature and the current value is obtained, then, according to the test of the optical module at normal temperature, the modulation current and the bias current set value of the optical module at the normal temperature are obtained, calculating by combining with the pre-obtained optical module test temperature lookup table to generate the temperature lookup table of the optical module, writing the temperature lookup table into the optical module, therefore, each optical module does not need to be tested within the working temperature range, the efficiency of generating the optical module temperature lookup table is improved, and the time required for generating the optical module temperature lookup table is shortened.

The APC loop according to the embodiment of the present invention will be explained below.

FIG. 1 is a schematic diagram of an APC loop control circuit according to the embodiment of the present invention. Referring to fig. 1, the control circuit includes: a bias current circuit and a modulation current circuit, wherein,

the modulation current circuit includes: a first triode V1, a second triode V2 and a first resistor R1;

the bias current circuit includes: a third laser triode V3, a first operational amplifier A1, a second operational amplifier A2, a third comparator A3, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and an inductor L1, wherein,

the base electrode of the first laser triode V1 is connected with a first modulation current (MOD-), the emitter electrode is connected with the emitter electrode of the second laser triode V2 and is connected with a preset Voltage (VCC), and the emitter electrode is connected with the emitter electrode of the second laser triode V2 and is connected with one end of a first resistor R1;

the base of the second laser triode V2 is connected with a second modulation current (MOD +);

the other end of the first resistor R1 is grounded;

the negative phase end of the first operational amplifier A1 is connected with one end of a second resistor R2, the positive phase end is connected with one end of a second resistor R2, and the output end is connected with the other end of the second resistor R2;

the negative phase end of the second operational amplifier A2 is connected with one end of a third resistor R3, the positive phase end is connected with one end of a fourth resistor R4, and the output end is connected with the other end of the third resistor R3;

one end of the fourth resistor R4 is also connected with one end of the inductor L1, the other end of the fourth resistor R4 is grounded, and the other end of the inductor L1 is connected with a preset voltage;

the negative phase end of the third comparator A3 is connected with the output end of the first operational amplifier A1, the positive phase end of the third comparator A3 is connected with the output end of the second operational amplifier A2, and the output end of the third comparator A3 is connected with the base electrode of the third laser triode V3;

an emitter of the third laser triode V3 is connected with one end of a fifth resistor R5, and a collector of the third laser triode V3 is connected with a collector of the second laser triode V2;

the other end of the fifth resistor R5 is connected to ground.

The second laser triode V2 is a laser LD, the first operational amplifier A1 is a backlight diode PD, and the PD is used for converting the induced light signal into a corresponding electric signal according to the intensity of the induced luminosity, and carrying out amplification and operation to obtain a required modulation signal;

MOD +, MOD-is the modulation current signal input, Ibias is the bias current flowing through LD, the magnitude of the bias current determines the magnitude of the optical power;

vset (the non-inverting terminal of the third comparator a 3) is a set voltage reference point for the target optical power;

after the PD detects the output light of the LD, the output light signal of the LD is amplified by the operational amplifier a1 and output to the inverting input terminal of the comparator A3, and meanwhile, the adjusted Vset reference voltage is sent to the non-inverting terminal of the comparator A3 and output to the third comparator V3 after comparison;

the third comparator A3 and the third laser triode V3 form a direct current constant current source for adjusting the bias current Ibias of the LD, when the output light power of the LD is reduced, the PD output is reduced, the input voltage of the inverting terminal of the comparator A3 is reduced, the output voltage of the comparator A3 is increased, the base current of the third laser triode V3 is increased, then the collector current Ibias is increased, the output light power of the LD is increased, the PD output is correspondingly increased, and the reduction of the output light power of the LD is counteracted. Otherwise, the current Ibias decreases, and the output optical power of the LD decreases.

Fig. 2 is a schematic diagram of a bias current, an output optical power and a loading voltage of a laser triode according to an embodiment of the invention. Referring to fig. 2, the abscissa represents the bias current, and the ordinate represents the output optical power and the applied voltage, respectively.

Ith is a current threshold point of the LD laser, when the bias current loaded on the LD laser in the forward direction does not exceed Ith, the luminous power of the LD laser can be ignored, and when the bias current exceeds Ith, the luminous power of the LD laser is obviously increased, and the Ibias and the LD output light power are close to a linear relation. As the bias current Ibias increases, the voltage applied across the LD laser also increases gradually.

If the temperature is increased, the output optical power of the LD is decreased, for example, the output optical power of the LD is decreased by the same current Ibias at a high temperature, that is, in fig. 2, when T1< T2, the output optical power corresponding to T1 is greater than the output optical power corresponding to T2 at the same bias current.

Fig. 3 is a schematic diagram of modulation characteristics of a laser triode according to an embodiment of the invention. Referring to fig. 3, the bias current Ibias determines the operating point of the LD laser, the modulation current signal is applied to the base of the laser through Imod (MOD +, MOD-), which is an ac differential signal, and Ibias is a dc signal, and as shown in fig. 3, when Ibias and Imod are applied to both ends (base and emitter) of the laser, a signal with modulated light intensity is obtained.

Fig. 4 is a flowchart illustrating a method for generating a temperature lookup table of an optical module according to an embodiment of the present invention. Referring to fig. 4, the process includes:

step 401, pre-dividing the ambient temperature into a plurality of temperature points, adjusting the optical power output by the testing optical module to a preset target optical power at each temperature point, and obtaining a testing temperature value of the testing optical module at the temperature point and a testing bias current setting register value;

in this step, the ambient temperature of the commonly used optical module is generally in the temperature range of-40 ℃ to 85 ℃, and thus the ambient temperature is taken to be-40 ℃ to 85 ℃, and the ambient temperature is divided into seven temperature points of-40 ℃, 20 ℃, 5 ℃, 25 ℃, 50 ℃, 70 ℃ and 85 ℃. Of course, in practical applications, the ambient temperature may be divided in other ways, for example, by dividing the ambient temperature by 5 ℃.

In the working process of the optical module, due to the influence of factors such as light emission and heat generation, the working temperature of the optical module is different from the ambient temperature, and the characteristics (optical power and extinction ratio) of an optical signal emitted by the optical module are related to the working temperature, so that the working temperature, namely the test temperature, corresponding to the optical module needs to be obtained at different ambient temperatures.

Since the MCU including the temperature sensor is built in the optical module, the MCU including the temperature sensor senses the temperature.

Table 1 is a parameter table of test temperature values and test bias current setting register values of the 1# test optical module at various temperature points, which are obtained in the embodiment of the present invention.

TABLE 1

In the context of table 1, the following,

SN, which is the serial number of the test optical module;

in a column where the test temperature is located, the second row value is a temperature point value (-40 ℃ -85 ℃), the third row value is a circuit board temperature obtained by actually measuring the circuit board by a temperature sensor in the MCU under the corresponding temperature point of the test optical module, namely the test temperature value, and the unit is;

and in a column where the test bias current setting register value is located, the second row value is a temperature point value (-40-85 ℃), and the third row value is a test bias current setting register value obtained when the test optical module adjusts the optical power output by the test optical module to a preset target optical power at a corresponding temperature point, and decimal (Dec) is adopted for counting without units. Namely, testing each temperature point of the optical module under the condition of appointed environment temperature (-40 ℃ -85 ℃), adjusting the optical power output by the LD to the APCset register value when the target optical power value is-2.5 decibel milliwatts (dBm), and obtaining decimal data. In practical applications, the range of the APCset register has a minimum value of 0 and a maximum value of 255.

And the interval test sample 1# module is used for taking a plurality of test temperature points within the range of-40-85 ℃ of the ambient temperature, adjusting the optical power to-2.5 dBm, adjusting the extinction ratio to a target value of 6.5DB, and recording a bias current set value APCset and a modulation current set value MODset at each temperature point.

Step 402, adjusting the extinction ratio output by the test optical module to a preset target extinction ratio, and acquiring a test modulation current setting register value of the test optical module at each temperature point;

in this step, on the basis of obtaining the test bias current setting register value in step 401, the extinction ratio of the test optical module is adjusted to a preset target extinction ratio, so as to obtain the test modulation current setting register value of the test optical module at the temperature point; or, after obtaining the test bias current setting register value of each temperature point in step 401, the test optical module is placed at each temperature point again, and the extinction ratio of the test optical module is adjusted to the preset target extinction ratio, so as to obtain the test modulation current setting register value of the test optical module at each temperature point respectively.

Table 2 is a parameter table of test temperature values and test modulation bias current setting register values of the 1# test optical module at various temperature points, which are obtained in the embodiment of the present invention.

TABLE 2

In the context of Table 2, the following examples are,

SN, which is the serial number of the test optical module;

and in a field where the test modulation current setting register value is located, the second line value is a temperature point value (-40-85 ℃), and the third line is a test modulation current setting register value obtained when the extinction ratio output by the test optical module is adjusted to a preset target extinction ratio under a corresponding temperature point by the test optical module, wherein the decimal (Dec) is adopted for counting without units. Namely, testing each temperature point of the optical module under the condition of appointed environment temperature (-40 ℃ -85 ℃), adjusting the extinction ratio output by the LD to the MODset register value when the target extinction ratio is 6.5 Decibels (DB), and taking the result as decimal data. In practical applications, the range of the MODset register has a minimum value of 0 and a maximum value of 255.

In practical application, a fixed bias current can be used to set a reference point, the optical power is stabilized by an APC loop, and the extinction ratio is stabilized, and then the writing of the optical module temperature lookup table is completed by a three-point calibration method, for example, the optical module is respectively placed at a working low temperature point T1, a normal temperature point T2, and a working high temperature point T3, the modulation current is adjusted to make the extinction ratio a preset target value, the modulation current setting values corresponding to the three temperature points are respectively set as a1, a2, and A3, the application program automatically fits a modulation current setting value-temperature curve to { T1, T2, T3}, { a1, a2, and A3} by using a two-fold line method, and further obtains the modulation current setting value of the temperature point corresponding to the temperature lookup table, and writes the lookup table data into the optical module.

Step 403, performing normalization processing on the obtained test bias current setting register value to obtain a bias current normalization slope parameter of a temperature interval formed by each temperature point; normalizing the obtained test modulation current setting register value to obtain a temperature interval modulation current normalization slope parameter formed by each temperature point;

in this step, normalizing the obtained test bias current setting register value, and obtaining a bias current normalized slope parameter of a temperature interval formed by each temperature point includes:

a11, forming corresponding temperature intervals according to the divided temperature points;

in this step, as described above, if the ambient temperature is divided into seven temperature points of-40 ℃, -20 ℃, 5 ℃, 25 ℃, 50 ℃, 70 ℃ and 85 ℃, the temperature ranges are [ -40, -20], [ -20, -5], [5, 25], [25, 50], [50, 70], respectively.

A12, obtaining a test bias current setting register value of a preset temperature point;

in this step, it is preferable that the preset temperature point is 25 ℃.

A13, obtaining the difference value of the test temperature value corresponding to each temperature point interval;

in this step, each temperature point interval corresponds to two test temperature values, for example, for the temperature interval [ -40, -20], the corresponding test temperature value interval is [ -22.6, -2.72], and then the difference between the test temperature values is 19.88.

A14, obtaining the difference value of the test bias current setting register value corresponding to each temperature point interval;

in this step, similar to step a13, each temperature range corresponds to two test bias current setting register values, for example, for a temperature range [ -40, -20], including two temperature points, i.e., an upper temperature point and a lower temperature point, the corresponding test bias current setting register value range is [48, 49], including the test bias current setting register value corresponding to the upper temperature point and the test bias current setting register value corresponding to the lower temperature point, the difference between the test bias current setting register values is 1.

And A15, dividing the difference value of the test bias current setting register value of the temperature point interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test bias current setting register value of the preset temperature point to obtain the bias current normalized slope parameter of the temperature interval.

In this step, the formula for calculating the normalized slope parameter of the bias current is:

in the formula,

k_bnormalizing the slope parameter for the bias current;

Table 3 is a table of normalized slope parameters of the bias current corresponding to each temperature point interval calculated according to table 1.

TABLE 3

In the context of Table 3, the following examples are,

for the situation that the ambient temperature of the optical module exceeds 85 ℃, the bias current normalized slope parameter of the optical module is the same as the bias current normalized slope parameter in the temperature point range of 70-85 ℃.

In table 3, the test data of table 1 and table 2 of the 1# module test are processed as the basis: and respectively calculating the normalized slope of each temperature interval of the set values of the bias current APCset and the modulation current MODset according to a normalized slope parameter calculation formula. In the examples of the present invention, normalization treatment was performed with a set value at room temperature of 25 ℃.

Normalizing the obtained test modulation current setting register value, and obtaining the temperature interval modulation current normalization slope parameter formed by each temperature point comprises the following steps:

a21, forming corresponding temperature intervals according to the divided temperature points;

a22, obtaining a test modulation current setting register value of a preset temperature point;

in this step, it is preferable that the preset temperature point is 25 ℃.

A23, obtaining the difference value of the test temperature value corresponding to each temperature point interval;

a24, obtaining the difference value of the test modulation current setting register value corresponding to each temperature point interval;

and A25, dividing the difference value of the test modulation current setting register value of the temperature point interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test modulation current setting register value of the preset temperature point to obtain the modulation current normalization slope parameter of the temperature interval.

In this step, the formula for calculating the normalized slope parameter of the modulation current is:

in the formula,

k_mnormalizing the slope parameter for the modulated current;

Table 4 is a modulation current normalized slope parameter table corresponding to each temperature point interval calculated according to table 2.

TABLE 4

In the context of Table 4, the following examples are,

for the condition that the ambient temperature of the optical module exceeds 85 ℃, the modulation current normalized slope parameter of the optical module is the same as the modulation current normalized slope parameter in the temperature point interval of 70-85 ℃.

Preferably, after obtaining the bias current normalized slope parameter and the modulation current normalized slope parameter of each temperature point interval, a mapping relationship between the temperature point and the bias current normalized slope parameter is constructed, and a mapping relationship between the temperature point and the modulation current normalized slope parameter is constructed. Therefore, according to the temperature point, the bias current normalized slope parameter and the modulation current normalized slope parameter corresponding to the temperature point can be obtained.

FIG. 5 is a diagram illustrating normalized slope parameters according to an embodiment of the present invention. Referring to fig. 5, the abscissa of the graph is the ambient temperature, and the ordinate of the graph is the bias current normalized slope parameter or the modulation current normalized slope parameter, and the graph includes seven temperature point intervals, each temperature point interval corresponds to a normalized slope, which is K1 to K7, where the ordinate of 0 indicates that the register value corresponding to the normalized slope parameter is 0, and the ordinate of 1 indicates that the register value corresponding to the normalized slope parameter is 255. The normalized slope trend line is divided into 7 segments, and the slope of each segment of the normalized slope trend line is known, so that in the subsequent application, only the compensation value (working temperature) of the T temperature point is acquired, and the compensation value of the whole trend line can be deduced from the segmented slope of the normalized slope trend line.

Step 404, adjusting the optical power output by the optical module to be applied to a preset target optical power, and adjusting the output extinction ratio to a preset target extinction ratio, and respectively obtaining a working temperature value, a bias current setting register value and a modulation current setting register value of the optical module to be applied in a normal temperature environment;

in this step, if the optical module needs to be set in a working state, a bias current normalization slope parameter and a modulation current normalization slope parameter in a temperature interval need to be written in the optical module, so that the optical module can adjust a bias current setting register value and a modulation current setting register value in real time according to the change of the working temperature, thereby maintaining the constancy of the optical power and the extinction ratio of the optical module.

In a similar way to the steps 401 and 402, a bias current setting register value and a modulation current setting register value of the optical module to be applied at a set operating temperature can be obtained.

In the embodiment of the invention, a processing module sample 2# is communicated with an MCU (microprogrammed control unit) singlechip through an external program under the environment of the ambient temperature of 30 ℃, the set values of an APCset register and an MODset register are adjusted to obtain the target optical power of-2.5 dBm and the extinction ratio of 6.5DB, and the adjusted set values of the APCset register and the MODset register are respectively a bias current set register value and a modulation current set register value under the set working temperature.

Preferably, the normal temperature environment is 25 ℃ or 30 ℃.

Step 405, setting a register value according to the obtained working temperature value and the bias current, and generating a bias current temperature lookup table of the optical module to be applied by combining a bias current normalization slope parameter obtained in advance; and generating a modulation current temperature lookup table of the optical module to be applied according to the acquired working temperature value and the modulation current setting register value and by combining a modulation current normalization slope parameter acquired in advance, and writing the generated bias current temperature lookup table and the generated modulation current temperature lookup table into the optical module to be applied.

In this step, the generating of the bias current temperature lookup table of the optical module to be applied according to the obtained operating temperature value and the bias current setting register value and by combining the pre-obtained bias current normalization slope parameter includes:

b11, inquiring a bias current normalized slope parameter of a temperature interval formed by each temperature point obtained in advance, and obtaining a bias current normalized slope value corresponding to the working temperature value;

in this step, a temperature point interval corresponding to the working temperature value is searched from the bias current normalization slope parameter obtained in advance, and a bias current normalization slope value of the interval is obtained.

B12, calculating the bias current setting register value of other temperature points in the temperature point interval according to the slope value and the bias current setting register value;

in this step, the formula for calculating the bias current setting register values of other temperature points in the temperature point interval is as follows:

I_bt＝I_bw-k_b×(T_w-T_t)×I_bc

in the formula,

T_wis the working temperature value;

In the embodiment of the invention, according to the obtained APCset and MODset set values under the environment temperature of 30 degrees, back calculation is carried out by the normalized slope, and bias current APCset temperature lookup table data and modulation current MODset temperature lookup table data are obtained. For example, as described above, when the temperature monitored by the MCU is T1 at an ambient temperature of 30 degrees, and the optical power and the extinction ratio are adjusted to target values, the APCset set value at this time is APCset1, and the MODset value is MODset1, referring to tables 3, 4 and fig. 5, if T1 is in the K3 segment, the APCset and MODset compensation values of other temperature points T2 in the K3 segment can be obtained by the above formula, after obtaining the compensation values, the values of the APCset compensation table or the MODset compensation table in the whole temperature interval can be obtained by calculating the normalized slope on the basis of the obtained normalized slope of the temperature compensation table segment, and the PC program writes the setting values of the temperature points in the compensation table into the MCU software through communication with the MCU monolithic processor, thereby completing the module debugging.

Therefore, according to the slope value and the bias current setting register value, the bias current setting register value corresponding to each working temperature in the temperature point interval can be obtained through calculation, and therefore testing of each temperature point is avoided.

And B13, calculating the bias current setting register value of each temperature point in the adjacent temperature point interval according to the bias current setting register value corresponding to the upper and lower limit temperature points of the temperature point interval and the bias current normalized slope parameter of the adjacent temperature point interval, until the bias current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a bias current temperature lookup table.

In this step, the formula for calculating the bias current setting register value of each temperature point in the interval of adjacent temperature points is as follows:

I_bt'＝I_bwu-k_b'×(T_w'-T_t')×I_bc

in the formula,

I_bwusetting a register value for a bias current corresponding to the intersection temperature of a temperature point interval corresponding to the working temperature and an adjacent temperature point interval, namely setting the register value for the bias current corresponding to an upper limit temperature point or a lower limit temperature point of the temperature point interval corresponding to the working temperature;

T_w'the intersection temperature value is obtained;

In practical application, the generating of the bias current temperature lookup table of the optical module to be applied according to the obtained operating temperature value and the bias current setting register value and by combining a pre-obtained bias current normalized slope parameter may include:

b15, inquiring a bias current normalized slope parameter of a temperature interval formed by each temperature point obtained in advance, and obtaining a bias current normalized slope value corresponding to the working temperature value;

b16, constructing a coordinate system of the temperature and bias current setting register values, and constructing a temperature point interval straight line corresponding to the working temperature value by using the temperature as an abscissa, the bias current setting register value as an ordinate, the bias current setting register value corresponding to the working temperature value as a base point, and the bias current normalized slope value corresponding to the working temperature value as a slope;

b17, obtaining the bias current setting register values corresponding to the upper and lower limit temperature points of the constructed straight line, constructing the straight line of the adjacent temperature point intervals by taking the bias current normalized slope value corresponding to the adjacent temperature point intervals as the slope, and generating the bias current temperature lookup table represented by the coordinate system.

The method for generating the temperature interval modulation current temperature lookup table of the optical module to be applied by combining the modulation current normalization slope parameter obtained in advance according to the obtained working temperature value and the modulation current setting register value comprises the following steps:

b21, inquiring a temperature interval modulation current normalization slope parameter formed by each temperature point obtained in advance, and obtaining a modulation current normalization slope value corresponding to the working temperature value;

in this step, a temperature point interval corresponding to the working temperature value is searched from the modulated current normalized slope parameter, and a slope value of the interval is obtained.

B22, calculating the modulation current setting register value of other temperature points in the temperature point interval according to the slope value and the modulation current setting register value;

in this step, the formula for calculating the modulation current setting register values of other temperature points in the temperature point interval is as follows:

I_mt＝I_mw-k_m×(T_w-T_t)×I_mc

in the formula,

T_wis the working temperature value;

Therefore, according to the slope value and the modulation current setting register value, the modulation current setting register value corresponding to each working temperature in the temperature point interval can be calculated, and the modulation current normalized slope parameter of the temperature point interval can be obtained.

And B23, calculating the modulation current setting register value of each temperature point in the adjacent temperature point interval according to the modulation current setting register value corresponding to the upper and lower limit temperature points of the temperature point interval and the modulation current normalization slope parameter of the adjacent temperature point interval, until the modulation current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a modulation current temperature lookup table.

In this step, the formula for calculating the modulation current setting register value of each temperature point in the adjacent temperature point interval is as follows:

I_mt'＝I_mwu-k_m'×(T_w'-T_t')×I_mc

in the formula,

I_mwusetting a register value for a modulation current corresponding to the intersection temperature of a temperature point interval corresponding to the working temperature and an adjacent temperature point interval, namely setting the register value for the modulation current corresponding to an upper limit temperature point or a lower limit temperature point of the temperature point interval corresponding to the working temperature;

T_w'the intersection temperature value is obtained;

Certainly, in practical applications, the generating of the temperature interval modulation current temperature lookup table of the optical module to be applied according to the obtained operating temperature value and the modulation current setting register value and by combining the modulation current normalization slope parameter obtained in advance may also include:

b25, inquiring a temperature interval modulation current normalization slope parameter formed by each temperature point obtained in advance, and obtaining a modulation current normalization slope value corresponding to the working temperature value;

b26, constructing a coordinate system of the temperature and modulation current setting register value by using the temperature as an abscissa and the modulation current setting register value as an ordinate, constructing a temperature point interval straight line corresponding to the operating temperature value by using the modulation current setting register value corresponding to the operating temperature value as a base point and the modulation current normalized slope value corresponding to the operating temperature value as a slope;

b27, obtaining modulation current setting register values corresponding to the upper and lower limit temperature points of the constructed straight line, constructing the straight line of the adjacent temperature point intervals by taking the modulation current normalization slope value corresponding to the adjacent temperature point intervals as the slope, and generating a modulation current temperature lookup table represented by a coordinate system.

Therefore, after the modulation current normalization slope parameter of the adjacent temperature point interval is obtained, the modulation current normalization slope parameter of the next temperature point interval adjacent to the adjacent temperature point interval can be obtained through the formula of the modulation current normalization slope parameter of the adjacent temperature point interval, and therefore the modulation current normalization slope parameter of all the temperature point intervals is obtained. That is, when the normalized slope of the compensation table and the set value of one temperature point at normal temperature are known, the compensation values of other temperature points can be calculated from the formula.

Table 5 is a parameter schematic table of optical power output by the optical module and an extinction ratio obtained by writing the generated optical module temperature lookup table into the optical module and controlling the optical module according to the written optical module temperature lookup table in the embodiment of the present invention.

TABLE 5

Temperature Point/. degree.C	-40	-20	-5	0	25	50	70	85
									Optical power/dBm	-2.4	-2.46	-2.45	-2.49	-2.51	-2.5	-2.45	-2.42
Extinction ratio/DB	6.44	6.52	6.56	6.61	6.69	6.63	6.58	6.61

In the context of Table 5, the following examples are given,

the optical module obtains the working temperature corresponding to the ambient temperature through the MCU under the set ambient temperature, for example, under a plurality of temperature points within-40 ℃ to 85 ℃, searches the optical module temperature lookup table, and obtains the bias current and the modulation current corresponding to the working temperature, thereby controlling the optical power and the extinction ratio of the optical module to be stable.

As can be seen from table 5, the measured values of the optical power and the extinction ratio are close to the set target: the optical power is-2.5 dBm, and the extinction ratio is 6.5DB, which shows that the method for generating the optical module temperature lookup table is feasible.

As can be seen from the above, the method for generating an optical module temperature lookup table according to the embodiment of the present invention obtains, in advance, each bias current setting register value and modulation current setting register value under the predetermined optical power and extinction ratio based on the P-I curve and the temperature characteristic of the optical module laser diode, performs processing by combining with a mathematical normalization method to obtain a current normalization slope parameter, and in subsequent applications, calculating current values at various temperature points according to the bias current setting register value and the modulation current setting register value of the optical module at normal temperature and the current normalization slope parameter obtained in advance, therefore, a temperature lookup table is generated and written into the optical module, so that the bias current setting and the modulation current setting of the optical module are effectively controlled, the bias current and the modulation current are in the working temperature range of the optical module, and the optical power and the extinction ratio meet the use requirements. In the generation process of the temperature lookup table, only a normal-temperature test is needed for each optical module, so that low-temperature and high-temperature test resources in the conventional method are saved, the efficiency of generating the optical module temperature lookup table is improved, the time required for generating the optical module temperature lookup table is reduced, and the production cost of the optical module is reduced; furthermore, low-temperature and high-temperature tests of the optical module are avoided, the processing time is effectively saved, and the occupation of production resources is reduced; and moreover, the production process of the optical module is simplified through a new processing flow.

Fig. 6 is a schematic structural diagram of an apparatus for generating an optical module temperature lookup table according to an embodiment of the present invention. Referring to fig. 6, the apparatus includes: a test bias current acquisition module, a test modulation current acquisition module, a normalization processing module, an application optical module current acquisition module and a temperature lookup table generation module, wherein,

Wherein, the test bias current acquisition module comprises: a temperature interval dividing unit, a test temperature difference calculating unit, a test bias current difference calculating unit, a bias current normalized slope calculating unit, a test modulation current difference calculating unit, and a modulation current normalized slope calculating unit (not shown in the figure), wherein,

The temperature lookup table generation module comprises: a bias current normalization slope obtaining unit, a bias current setting register value obtaining unit, a bias current temperature lookup table generating unit, a modulation current normalization slope obtaining unit, a modulation current setting register value obtaining unit, and a modulation current temperature lookup table generating unit (not shown in the figure), wherein,

In the embodiment of the invention, the bias current temperature lookup table and the modulation current temperature lookup table can be combined to obtain the temperature lookup table.

Those skilled in the art will appreciate that all or part of the steps in the method for implementing the above embodiments may be implemented by relevant hardware instructed by a program, and the program may be stored in a computer readable storage medium, such as: ROM/RAM, magnetic disk, optical disk, etc.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention.

Claims

1. A method of generating a light module temperature lookup table, the method comprising:

normalizing the obtained test bias current setting register value to obtain a bias current normalized slope parameter of a temperature interval formed by each temperature point;

normalizing the obtained test modulation current setting register value to obtain a temperature interval modulation current normalization slope parameter formed by each temperature point, wherein the normalization slope parameter comprises the following steps: forming a corresponding temperature interval according to each divided temperature point; acquiring a test modulation current setting register value of a preset temperature point; acquiring a difference value of a test temperature value corresponding to each temperature interval; obtaining the difference value of the test modulation current setting register value corresponding to each temperature interval; for each temperature interval, dividing the difference value of the test modulation current setting register value of the temperature interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test modulation current setting register value of a preset temperature point to obtain a modulation current normalization slope parameter of the temperature interval;

2. The method according to claim 1, wherein the step of normalizing the obtained test bias current setting register value to obtain the normalized slope parameter of the bias current of the temperature interval formed by each temperature point comprises:

acquiring a difference value of a test temperature value corresponding to each temperature interval;

obtaining the difference value of the test bias current setting register value corresponding to each temperature interval;

and for each temperature interval, dividing the difference value of the test bias current setting register value of the temperature interval by the difference value of the test temperature value, and multiplying the difference value by the reciprocal of the test bias current setting register value of a preset temperature point to obtain the bias current normalized slope parameter of the temperature interval.

3. The method of claim 1, wherein the bias current normalized slope parameter is obtained by the formula:

in the formula,

normalizing the slope parameter for the bias current;

setting a register value for the test bias current corresponding to the upper limit temperature of the temperature interval;

setting a register value for the test bias current corresponding to the lower limit temperature of the temperature interval;

for upper temperature rangeA test temperature value of (a);

the temperature is a test temperature value corresponding to the lower limit temperature of the temperature interval;

the register value is set for the test bias current at the preset temperature point.

4. The method of claim 1, wherein the modulation current normalized slope parameter is obtained by the formula:

in the formula,

normalizing the slope parameter for the modulated current;

setting a register value for the test modulation current corresponding to the upper limit temperature of the temperature interval;

setting a register value for the test modulation current corresponding to the lower limit temperature of the temperature interval;

a test temperature value corresponding to the upper limit temperature of the temperature interval;

setting a register value for the test modulation current of the preset temperature point.

5. The method of any one of claims 1 to 4, wherein after obtaining the bias current normalized slope parameter and the modulation current normalized slope parameter for the temperature interval formed at each temperature point, the method further comprises:

6. The method according to claim 5, wherein the generating the bias current temperature lookup table of the optical module to be applied according to the obtained operating temperature value, the bias current setting register value, and the pre-obtained bias current normalized slope parameter comprises:

calculating bias current setting register values of other temperature points in the temperature interval according to the slope value and the bias current setting register value;

and calculating the bias current setting register value of each temperature point in the adjacent temperature interval according to the bias current setting register value corresponding to the upper and lower limit temperature points of the temperature interval and the bias current normalized slope parameter of the adjacent temperature interval, until the bias current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a bias current temperature lookup table.

7. The method of claim 6, wherein the formula for calculating the bias current setting register values for other temperature points in the temperature interval is:

in the formula,

at other working temperatures within a temperature range corresponding to the working temperatureSetting a register value by the bias current;

setting a register value for the bias current corresponding to the working temperature;

normalizing slope parameters for the bias current in a temperature interval corresponding to the working temperature;

is the working temperature value;

8. The method of claim 7, wherein the formula for calculating the bias current setting register value for each temperature point in the adjacent temperature interval is:

in the formula,

at operating temperature within adjacent temperature intervalsSetting a register value by the bias current;

setting a register value for a bias current corresponding to the intersection temperature of a temperature interval corresponding to the working temperature and an adjacent temperature interval;

normalizing slope parameters for bias currents in adjacent temperature intervals;

the intersection temperature value is obtained;

9. The method according to claim 5, wherein the generating the bias current temperature lookup table of the optical module to be applied according to the obtained operating temperature value, the bias current setting register value, and the pre-obtained bias current normalized slope parameter comprises:

establishing a coordinate system of temperature and bias current setting register values, taking the temperature as an abscissa, the bias current setting register values as an ordinate, the bias current setting register values corresponding to the working temperature values as a base point, and the bias current normalization slope values corresponding to the working temperature values as a slope, and establishing a temperature interval straight line corresponding to the working temperature values;

and acquiring bias current setting register values corresponding to upper and lower limit temperature points of the constructed straight line, constructing the straight line of the adjacent temperature point intervals by taking the bias current normalization slope value corresponding to the adjacent temperature intervals as the slope, and generating a bias current temperature lookup table represented by a coordinate system.

10. The method according to claim 5, wherein the generating a temperature interval modulation current temperature lookup table of the optical module to be applied according to the obtained operating temperature value and the modulation current setting register value and by combining a modulation current normalization slope parameter obtained in advance comprises:

calculating the modulation current setting register values of other temperature points in the temperature interval according to the slope value and the modulation current setting register value;

and calculating the modulation current setting register value of each temperature point in the adjacent temperature interval according to the modulation current setting register value corresponding to the upper and lower limit temperature points of the temperature interval and the modulation current normalization slope parameter of the adjacent temperature interval, until the modulation current setting register value of each temperature interval of the optical module to be applied is calculated, and generating a modulation current temperature lookup table.

11. The method of claim 10, wherein the formula for calculating the modulation current setting register values of other temperature points in the temperature interval is:

in the formula,

at other working temperatures within a temperature range corresponding to the working temperatureSetting a register value by the modulation current;

setting a register value for the modulation current corresponding to the working temperature;

normalizing slope parameters for the modulation current of a temperature interval corresponding to the working temperature;

is the working temperature value;

12. The method of claim 10, wherein the formula for calculating the modulation current setting register value for each temperature point in the adjacent temperature interval is:

in the formula,

at operating temperature within adjacent temperature intervalsSetting a register value by the modulation current;

setting a register value for a modulation current corresponding to the intersection temperature of a temperature interval corresponding to the working temperature and an adjacent temperature interval;

normalizing slope parameters for modulation currents of adjacent temperature intervals;

the intersection temperature value is obtained;