阅读说明：本技术 一种光学器件参数锁定的集成闭环反馈pwm控制系统和方法 (Integrated closed-loop feedback PWM control system and method for optical device parameter locking ) 是由 谭旻 明达 于 2019-11-27 设计创作，主要内容包括：本发明属于光电芯片设计领域,更具体地,涉及一种光学器件参数锁定的集成闭环反馈PWM控制系统和方法。光-电转换模块将光子器件中能够反映光子器件参数变化的光信号转换为电信号；算法处理前端模块对转换后的电信号进行前端处理转换为数字信号,从而输入给算法控制模块进行处理；算法控制模块根据相应的参数锁定算法计算出代表着PWM信号占空比的数字信号；然后通过脉冲宽度调制输出模块输出对应占空比的脉冲信号,从而控制热调器来锁定光子器件参数。本发明通过PWM控制方式,在开/关这两种状态下可实现100％的能量转换效率,能显著提高能量转换效率；而且,节约了芯片面积,降低了芯片制造成本。(The invention belongs to the field of photoelectric chip design, and particularly relates to an integrated closed-loop feedback PWM control system and method for optical device parameter locking. The optical-electrical conversion module converts optical signals capable of reflecting parameter changes of the photonic device in the photonic device into electrical signals; the algorithm processing front-end module performs front-end processing on the converted electric signals to convert the electric signals into digital signals, and then the digital signals are input to the algorithm control module for processing; the algorithm control module calculates a digital signal representing the duty ratio of the PWM signal according to a corresponding parameter locking algorithm; and then, a pulse signal corresponding to the duty ratio is output through a pulse width modulation output module, so that the thermal modulator is controlled to lock the parameters of the photonic device. According to the invention, through a PWM control mode, 100% of energy conversion efficiency can be realized in the on/off states, and the energy conversion efficiency can be obviously improved; moreover, the chip area is saved, and the chip manufacturing cost is reduced.)

1. An integrated closed-loop feedback PWM control system for optical device parameter locking is characterized by comprising a light-electricity conversion module, an algorithm processing front-end module, an algorithm control module, a pulse width modulation output module and a heat regulator which are sequentially connected;

the optical-electric conversion module is used for converting optical signals in the photonic device into electric signals;

the algorithm processing front-end module is used for converting the electric signal into a digital signal and inputting the digital signal to the algorithm control module for processing;

the algorithm control module calculates a PWM duty ratio signal according to a corresponding parameter locking algorithm;

and the pulse width modulation output module generates a corresponding pulse signal according to the PWM duty ratio signal so as to control the heat regulator.

2. The integrated closed-loop feedback PWM control system of claim 1, further comprising a multiplexer and a demultiplexer for switching of the multiplexed photonic devices.

3. An integrated closed-loop feedback PWM control system according to claim 1 or 2, wherein the photo-electric conversion module is a photodiode or an optical probe.

4. An integrated closed-loop feedback PWM control system according to claim 1 or 2, wherein the algorithmic processing front end module comprises a transimpedance amplifier or an integrating circuit.

5. An integrated closed-loop feedback PWM control system according to claim 1 or 2, wherein the algorithmic processing front end module comprises an ADC module or a slope determination unit.

6. An integrated closed-loop feedback PWM control method for optical device parameter locking is characterized by comprising the following steps:

converting an optical signal within the photonic device into an electrical signal;

performing front-end processing on the electric signal, and converting the electric signal into a digital control signal;

calculating a PWM duty ratio signal according to the digital control signal and a corresponding parameter locking algorithm;

and generating a corresponding pulse signal according to the PWM duty ratio signal to control the heat regulator.

7. An integrated closed-loop feedback PWM control method according to claim 6, wherein for multiple photonic devices, a multiplexer and a demultiplexer are used to switch different photonic devices.

8. An integrated closed-loop feedback PWM control method applied to micro-ring resonator (MRR) parameter locking is characterized by comprising the following steps:

step 1, a photodiode detects the intensity of light at a download port or a through port, so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 3, converting the analog voltage signal into a digital control signal by using an ADC module or a slope judgment module;

step 4, the algorithm control module outputs a duty ratio signal to the pulse width modulation output module according to the wavelength locking algorithm and the digital control signal;

step 5, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

and 6, generating corresponding heat by the heat regulator according to the input PWM signal so as to change the temperature of the MRR.

9. An integrated closed-loop feedback PWM control method applied to Mach-Zehnder modulator (MZM) parameter locking is characterized by comprising the following steps:

step 1, detecting the light intensity of a photodiode at the output of a beam splitter so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 3, converting the analog voltage signal into a digital control signal by using an ADC module or a slope judgment module;

step 4, the algorithm control module outputs a duty ratio signal to the pulse width modulation output module according to the wavelength locking algorithm and the digital control signal;

step 5, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

and 6, generating corresponding heat by the heat regulator according to the input PWM signal so as to change the temperature of the MZM.

10. An integrated closed-loop feedback PWM control method applied to micro-ring resonator array parameter locking is characterized by comprising the following steps:

step 1, switching the N-path multiplexer and the N-path demultiplexer to a micro-ring resonator;

step 2, the photodiode detects the intensity of light at a through port or a download port of the micro-ring resonator, so as to generate photocurrent;

step 3, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 4, the ADC module or the slope judgment module converts the analog voltage signal into a digital control signal;

step 5, the algorithm control module outputs a duty ratio signal to a multi-path register according to a wavelength locking algorithm and the digital control signal, and then sends the duty ratio signal to a pulse width modulation output module;

step 6, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

step 7, the heat adjuster generates corresponding heat according to the input PWM signal, so as to change the temperature of the micro-ring resonator;

and 8, switching the N-path multiplexer and the N-path demultiplexer to the next micro-ring resonator.

Technical Field

The invention belongs to the field of photoelectric chip design, and particularly relates to an integrated closed-loop feedback PWM control system and method for optical device parameter locking.

Background

The silicon-based photonic device has the advantages of small size, compatibility with the traditional Complementary Metal Oxide Semiconductor (CMOS) process, easiness in large-scale integration and the like, and has very wide application in the fields of optical communication, optical calculation, optical sensing and the like. Since the silicon-based photonic device is susceptible to temperature variation of the operating environment, deviation of the manufacturing process, and variation of the input laser wavelength, and the operating state of the silicon-based photonic device shifts, in practical applications, a corresponding control technique is usually used to dynamically lock the optical parameters and the operating state of the silicon-based photonic device.

For example, the resonance wavelength of a silicon-based Micro Ring Resonator (MRR) composed of a straight waveguide and a ring waveguide is susceptible to shift due to environmental temperature change and manufacturing process variation, thereby deteriorating the operation performance of the MRR. The thermal modulator may control the temperature of the photonic device and thus control photonic device parameters such as the effective refractive index of the waveguide. In general, a closed-loop feedback control method based on a digital-to-analog converter (DAC), an analog-to-digital converter (ADC) and a thermal regulator can effectively control the temperature of the MRR to lock the resonant wavelength of the MRR, thereby dynamically stabilizing the operating state of the MRR.

For another example, the optimum bias point of a silicon-based mach-zehnder modulator (MZM) composed of a 3dB coupler and a phase shifter may be shifted by the influence of the environmental temperature variation, the manufacturing process variation, and the variation of the input laser wavelength, thereby affecting the modulation effect. In general, a closed-loop feedback bias control method based on a DAC, an ADC and a thermal modulator can effectively control the bias voltage or temperature of the MZM, lock the MZM to an optimal bias point, and thus achieve an optimal modulation effect.

In a conventional photonic device parameter control loop, a DAC is generally required to implement an output function, and an ADC is generally required to implement a function of an algorithm processing front end, which is easy to implement in a board-level circuit, but causes a problem of large chip area in an integrated circuit. Meanwhile, part of energy in the control method based on the DAC output is consumed on the DAC, and the energy conversion efficiency can not reach 100% theoretically, so the control method has the defect of low control efficiency. Particularly, for photonic device arrays such as MRR arrays, MZM arrays, etc., the closed-loop feedback control method based on DAC and ADC has more obvious disadvantages, and is difficult to realize large-scale integration.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide an integrated closed-loop feedback PWM control device and method for optical device parameter locking, and aims to solve the problems of large chip area, low energy efficiency and the like of the conventional DAC-based photonic device parameter closed-loop feedback locking method, so that stable control and locking of important photonic device parameters such as the resonance wavelength of MRR, the bias state of MZM and the like are realized.

In order to achieve the aim, the invention provides an integrated closed-loop feedback PWM control system for locking parameters of an optical device, which comprises a light-electricity conversion module, an algorithm processing front-end module, an algorithm control module, a pulse width modulation output module and a heat regulator which are sequentially connected;

the optical-electric conversion module is used for converting optical signals in the photonic device into electric signals;

the algorithm processing front-end module is used for converting the electric signal into a digital signal and inputting the digital signal to the algorithm control module for processing;

the algorithm control module calculates a PWM duty ratio signal according to a corresponding parameter locking algorithm;

and the pulse width modulation output module generates a corresponding pulse signal according to the PWM duty ratio signal so as to control the heat regulator.

Further, the system also includes a multiplexer and a demultiplexer for switching the multiplexed photonic devices.

Further, the photo-electric conversion module is a photodiode or an optical probe.

Further, the algorithmic processing front end module comprises a transimpedance amplifier or an integrating circuit.

Further, the algorithm processing front-end module comprises an ADC module or a slope judgment unit.

The invention also provides an integrated closed-loop feedback PWM control method for optical device parameter locking, which comprises the following steps:

converting an optical signal within the photonic device into an electrical signal;

the front end processes the electric signal and converts the electric signal into a digital control signal;

calculating a PWM duty ratio signal according to the digital control signal and a corresponding parameter locking algorithm;

and generating a corresponding pulse signal according to the PWM duty ratio signal to control the heat regulator.

Further, for multiplexed photonic devices, multiplexers and demultiplexers are used to switch different photonic devices.

The invention also provides an integrated closed-loop feedback PWM control method applied to parameter locking of a micro-ring resonator (MRR), which comprises the following steps:

step 1, a photodiode detects the intensity of light at a download port or a through port, so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 3, converting the analog voltage signal into a digital control signal by using an ADC module or a slope judgment module;

step 4, the algorithm control module outputs a duty ratio signal to the pulse width modulation output module according to the wavelength locking algorithm and the digital control signal;

step 5, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

and 6, generating corresponding heat by the heat regulator according to the input PWM signal so as to change the temperature of the MRR.

The invention also provides an integrated closed-loop feedback PWM control method applied to Mach-Zehnder modulator (MZM) parameter locking, which comprises the following steps:

step 1, detecting the light intensity of a photodiode at the output of a beam splitter so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 3, converting the analog voltage signal into a digital control signal by using an ADC module or a slope judgment module;

step 4, the algorithm control module outputs a duty ratio signal to the pulse width modulation output module according to the wavelength locking algorithm and the digital control signal;

step 5, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

and 6, generating corresponding heat by the heat regulator according to the input PWM signal so as to change the temperature of the MZM.

The invention also provides an integrated closed-loop feedback PWM control method applied to micro-ring resonator array parameter locking, which comprises the following steps:

step 1, switching the N-path multiplexer and the N-path demultiplexer to a micro-ring resonator;

step 2, the photodiode detects the intensity of light at a through port or a download port of the micro-ring resonator, so as to generate photocurrent;

step 3, amplifying the photocurrent into an analog voltage signal through a trans-impedance amplifier or an integrating circuit;

step 4, the ADC module or the slope judgment module converts the analog voltage signal into a digital control signal;

step 5, the algorithm control module outputs a duty ratio signal to a multi-path register according to a wavelength locking algorithm and the digital control signal, and then sends the duty ratio signal to a pulse width modulation output module;

step 6, the pulse width modulation output module generates PWM signals with corresponding duty ratios according to the input signals;

step 7, the heat adjuster generates corresponding heat according to the input PWM signal, so as to change the temperature of the micro-ring resonator;

and 8, switching the N-path multiplexer and the N-path demultiplexer to the next micro-ring resonator.

Compared with the prior art, the photon device parameter closed-loop feedback locking system and method based on PWM can realize 100% of energy conversion efficiency in the on/off states by the PWM control mode, only has dynamic power consumption during on/off level conversion, and can obviously improve the energy conversion efficiency in principle compared with the DAC control mode; on the other hand, because the heat regulator has the function of filtering, the PWM signal is directly applied to the heat regulator for heating without being filtered by an inductor module and a capacitor module with larger area, thereby saving the area of a chip, realizing lower difficulty and reducing the manufacturing cost of the chip.

Drawings

FIG. 1 is a basic principle diagram of a parameter closed-loop feedback locking method of a photonic device based on PWM.

Fig. 2 is a schematic diagram of a PWM signal controlled thermal modulator.

FIG. 3(a) is a block diagram of a MRR wavelength closed loop locking circuit for detecting a download port photocurrent;

fig. 3(b) is a block diagram of an MRR wavelength closed loop locking circuit that detects the through port photocurrent.

FIG. 4 is a block diagram of a closed loop feedback lock circuit for detecting MZM.

Fig. 5 is a block diagram of the MRR array closed loop lock circuit that detects the download/through port photocurrent through the multiplexer/demultiplexer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

According to the invention, a PWM-based photonic device parameter closed-loop feedback locking method is provided, and a schematic diagram of the method is shown in FIG. 1. The optical-to-electrical conversion module 102 converts an optical signal capable of reflecting the parameter change of the photonic device in the photonic device 101 into an electrical signal; the algorithm processing front-end module 103 performs front-end processing on the converted electric signal to convert the electric signal into a digital signal, and inputs the digital signal to the algorithm control module 104 for processing; the algorithm control module 104 calculates a digital signal representing the duty ratio of the PWM signal according to a corresponding parameter locking algorithm; then, the pulse width modulation output module 105 outputs a pulse signal corresponding to the duty ratio, so as to control the thermal modulator 106 to lock the photonic device parameter.

The principle of PWM signal control of the thermal modulator is shown in FIG. 2, taking PWM signal control of the N-type MOS transistor 201 as an example, the output voltage of the PWM method only has two states, namely, the power voltage (V)_DD) And ground voltage (V)_SS). When the output voltage is V_DDWhile MOS in the figureThe tube is completely conducted, the on-resistance is close to 0, and the energy is completely transmitted to the heat regulator 202; when the output voltage is V_SSIn the figure, the MOS tube is completely closed, the on-resistance is close to infinity, and no energy is transmitted at the moment. It can be seen that the photon device parameter closed-loop feedback locking method based on PWM provided by the invention has no energy loss in two states, i.e. the energy conversion efficiency is close to 100%. For the case that the P-type MOS transistor is controlled by the PWM signal, the energy conversion efficiency is also close to 100%, and details are not repeated. Therefore, the PWM control method has the advantages of high energy efficiency, simplicity in implementation and the like, and can remarkably improve the energy conversion efficiency.

The photon device parameter closed-loop feedback locking method based on PWM provided by the invention applies PWM closed-loop control to a new photon device parameter feedback control circuit, and has the advantages of high energy conversion efficiency, small chip area and easy realization. Through the PWM control mode, the energy conversion efficiency of 100% can be realized in both the on/off states, only the dynamic power consumption during on/off level conversion exists, and compared with the traditional DAC control mode, the energy conversion efficiency can be obviously improved in principle. Moreover, the heat regulator has the function of filtering, and the PWM signal is directly applied to the heat regulator for heating without being filtered by an inductor module and a capacitor module with larger area, so that the area of a chip is saved, and the manufacturing cost of the chip is reduced. In addition, compared with the traditional DAC circuit, the PWM output module has the characteristics of small chip area and low implementation difficulty, and can further reduce the manufacturing cost of the chip.

Furthermore, the photon device parameter closed-loop feedback locking method based on PWM provided by the invention can also realize the control of the photon device array through a multiplexing core control module (an optical-electric conversion module, an algorithm processing front end, an algorithm control module and the like). The method can overcome the defects of low energy conversion efficiency, large chip area and the like of the traditional method, thereby realizing more effective and reliable parameter control of the photonic device.

The following describes the specific embodiments of the control method applied to the micro-ring resonator (MRR), the mach-zehnder modulator (MZM), and the photonic device array in sequence, and refer to fig. 3 to 5, respectively.

Example one

Step 1, a photodiode 301 detects the intensity of light at a download port/through port, so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a transimpedance amplifier/integration circuit 302;

step 3, the ADC module or the slope judgment module 303 converts the input analog voltage signal into a digital control signal;

step 4, the algorithm control module 304 outputs a proper signal to a Pulse Width Modulation (PWM) output module 305 according to the wavelength locking algorithm and the input digital control signal;

step 5, the PWM output module 305 generates a PWM signal with a corresponding duty ratio according to the input signal;

step 6, the thermal modulator 306 generates the appropriate amount of heat based on the input PWM signal to change the MRR temperature.

The above steps 1 to 6 are repeated until the temperature of the MRR is stabilized.

Example two

Step 1, a photodiode 402 detects the intensity of light at the output of a beam splitter 401, so as to generate photocurrent;

step 2, amplifying the photocurrent into an analog voltage signal through a transimpedance amplifier/integration circuit 403;

step 3, the ADC module or the slope determination module 404 converts the input analog voltage signal into a digital control signal;

step 4, the algorithm control module 405 outputs a proper signal to the PWM output module 406 according to the wavelength locking algorithm and the input digital control signal;

step 5, the PWM output module 406 generates a PWM signal with a corresponding duty ratio according to the input signal;

step 6, the thermal modulator 407 generates an appropriate amount of heat according to the input PWM signal to change the temperature of the MZM.

Repeating steps 1 to 6 until the MZM reaches the optimum bias state.

EXAMPLE III

Step 1, switching an N-path multiplexer 501 and an N-path demultiplexer 502 to a first MRR in an N-path MRR array 503;

step 2, the photodiode detects the intensity of light at the MRR through port or the download port, so as to generate photocurrent;

step 3, amplifying the photocurrent into an analog voltage signal through a transimpedance amplifier/integration circuit 504;

step 4, the ADC module or the slope determination module 505 converts the input analog voltage signal into a digital control signal;

step 5, the algorithm control module 506 outputs a proper signal to the N-path register 507 according to the wavelength locking algorithm and the input digital control signal, and then sends the signal to the PWM output module 508;

step 6, the PWM output module 508 generates a PWM signal with a corresponding duty ratio according to the input signal;

step 7, the heat regulator 509 generates appropriate heat according to the input PWM signal to change the temperature of MRR;

and 8, repeating the steps 2 to 7 until the temperature of the MRR is stable.

And 9, switching the N-path multiplexer and the N-path demultiplexer to the next MRR.

Repeating the steps 2-8 until the temperature of the Nth MRR is stable.

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