CN114709708B - A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics - Google Patents

A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics Download PDF

Info

Publication number
CN114709708B
CN114709708B CN202210215550.XA CN202210215550A CN114709708B CN 114709708 B CN114709708 B CN 114709708B CN 202210215550 A CN202210215550 A CN 202210215550A CN 114709708 B CN114709708 B CN 114709708B
Authority
CN
China
Prior art keywords
frequency
temperature
signal
optical
voltage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210215550.XA
Other languages
Chinese (zh)
Other versions
CN114709708A (en
Inventor
郭弘
吴腾
陈子扬
于东睿
张宇飞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Peking University
Original Assignee
Peking University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Peking University filed Critical Peking University
Priority to CN202210215550.XA priority Critical patent/CN114709708B/en
Publication of CN114709708A publication Critical patent/CN114709708A/en
Application granted granted Critical
Publication of CN114709708B publication Critical patent/CN114709708B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
    • H01S3/1305—Feedback control systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/11—Mode locking; Q-switching; Other giant-pulse techniques, e.g. cavity dumping
    • H01S3/1106—Mode locking
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
    • H01S3/131—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation
    • H01S3/1317—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation by controlling the temperature

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optics & Photonics (AREA)
  • Automation & Control Theory (AREA)
  • Lasers (AREA)

Abstract

本发明公开了一种基于温控和压电陶瓷的光学频率梳重复频率锁定方法，其步骤包括：1)将参考频率信号与锁模激光器输出的光学频率梳接入频率误差信号产生模块，得到光学频率梳的重复频率与参考频率之差作为误差信号输入高速伺服控制模块；2)高速伺服控制模块根据输入的所述误差信号生成反馈控制信号并输入到电压控制模块；3)电压控制模块根据所述反馈控制信号生成目标电压信号并将其分别输入到锁模激光器中的压电陶瓷和低速伺服反馈控制模块，对重复频率进行动态调节；4)低速伺服反馈控制模块根据目标电压信号、压电陶瓷控制器当前的调控电压值计算谐振腔中光纤温度调节量；温度控制器根据所述光纤温度调节量调控谐振腔中光纤温度。

The invention discloses a method for locking the repetition frequency of an optical frequency comb based on temperature control and piezoelectric ceramics, and the steps include: 1) connecting a reference frequency signal and an optical frequency comb output by a mode-locked laser to a frequency error signal generation module, obtaining a difference between the repetition frequency of the optical frequency comb and the reference frequency as an error signal and inputting the difference into a high-speed servo control module; 2) the high-speed servo control module generates a feedback control signal according to the input error signal and inputs the feedback control signal into a voltage control module; 3) the voltage control module generates a target voltage signal according to the feedback control signal and inputs the target voltage signal into the piezoelectric ceramic and low-speed servo feedback control modules in the mode-locked laser respectively, and dynamically adjusts the repetition frequency; 4) the low-speed servo feedback control module calculates the temperature adjustment amount of an optical fiber in a resonant cavity according to the target voltage signal and the current control voltage value of a piezoelectric ceramic controller; and the temperature controller adjusts the temperature of the optical fiber in the resonant cavity according to the temperature adjustment amount of the optical fiber.

Description

Optical frequency comb repetition frequency locking method based on temperature control and piezoelectric ceramics
Technical Field
The invention relates to the field of time frequency transmission and measurement in information science, in particular to an optical frequency comb repetition frequency locking method based on temperature control and piezoelectric ceramics.
Background
The optical frequency comb is a mode-locked laser with stable frequency and phase, and is generated in the pursuit of more accurate time reference and high-precision measurement technology based on the time reference. The optical frequency comb is based on mode-locked lasers or microresonators and semiconductor technology and can produce a sequence of periodically stable laser pulses at a frequency that is repeated from tens of megahertz to hundreds of gigahertz. Besides being applied to the fields of high-precision measurement such as timing, astronomy, distance measurement and the like, the method also has mature commercial application.
As an example, in recent years, with the vigorous development of atomic clock technology, human definition of time is more and more accurate, and more powerful measurement means are provided for some basic physical researches. In order to effectively transmit these precise time-frequency signals while ensuring their accuracy, it is necessary to load a frequency reference onto the laser, and transmit it using transmission means such as a spatial optical path or an optical fiber path, one of which is to load onto an optical frequency comb. The use of an optical frequency comb as a medium has the advantage of a high signal-to-noise ratio, the possibility of delivering multiple radio frequencies and optical frequencies simultaneously, etc., compared to other methods (loading on optical frequencies, or radio frequency modulated continuous laser).
In order to load the frequency reference onto the optical frequency comb, the conventional method is to use a feedback control circuit to control a piezoelectric ceramic (PZT) to change the cavity length and lock the repetition frequency of the optical frequency comb to a reference source under a certain control temperature. While the locking range is limited due to the limited range of voltages applied by PZT (typically positive voltages, and less than hundred volts). If the ambient temperature changes drastically, even with temperature control of the mode-locked laser, the residual effects are sufficient to cause the heavy frequency to drift out of the PZT control range, resulting in a laser that cannot be locked for long periods of time. In addition, the voltage-telescopic response curve of PZT is not linear in the interval of 0 to hundred volts, and wide variations in this interval can cause instability of PID feedback, thereby affecting the quality of signal loading.
Disclosure of Invention
In order to solve the problems, the invention provides an optical frequency comb repetition frequency locking method based on temperature control and piezoelectric ceramics. And the temperature control set value is dynamically adjusted according to the voltage of the PZT by using a computing device, so that the temperature control set value and the PZT work cooperatively, and the long-time locking of the optical frequency comb is realized.
In order to achieve the above purpose, the invention adopts the following technical scheme:
An optical frequency comb locking method based on temperature control and piezoelectric ceramics comprises the following steps:
1) And connecting the reference frequency signal and the output signal of the optical frequency comb to be locked to a frequency error signal generating module to obtain the difference between the repetition frequency signal of the optical frequency comb output by the mode-locked laser and the reference frequency, namely, the error signal input of the servo module.
2) The error signal is used as the error input of the high-speed servo control module to perform feedback control. The output is amplified by a voltage control module, and piezoelectric ceramics (PZT) in the mode-locked laser is controlled to adjust the space optical path, so that the repetition frequency of the optical comb is dynamically adjusted.
3) Because the output of the voltage control module and the voltage applied by the PZT have certain limits, the feedback system can only adjust the repetition frequency of the optical comb in a small range. Because the length of the optical fiber is affected by temperature, the optical path of the optical fiber part in the resonant cavity of the mode-locked laser can be changed by controlling the temperature so as to slowly adjust the repetition frequency of the optical comb.
4) The output of the voltage control module is then taken as the input of the low speed servo feedback control module. In the low-speed servo feedback control module, a 'target voltage', namely a target voltage output by the voltage control module, needs to be set, and feedback is started
Previously, the temperature-controlled bias temperature was set to the current temperature. The temperature control setting temperature is started to be feedback controlled, and the temperature control setting temperature is regulated when the voltage applied by the PZT deviates from the set target voltage, so that the PZT voltage is maintained within a certain range on the basis of ensuring the frequency locking. The low-speed servo feedback control module calculates the temperature adjustment quantity of the optical fiber in the resonant cavity of the mode-locked laser according to the target voltage signal and the current regulation voltage value of the piezoelectric ceramic controller.
5) By using the structure, the output voltage of the voltage control module is stabilized near a certain set value through slow feedback adjustment temperature control, and the set range cannot be floated, so that the repeated frequency of the optical comb laser can be locked for a long time.
The invention has the beneficial effects that:
In order to ensure the locking bandwidth, PZT is generally used for feedback locking of the optical comb, but the application voltage range of the PZT is limited, and the PZT breaks down and loses functions due to the fact that the application voltage range of the PZT exceeds the application voltage range of the PZT, so that the locking range of a scheme for feedback locking by using the PZT is limited; in addition, the PZT stretches and contracts in a non-linear fashion with the applied voltage, which also affects the locking result. The laser temperature is generally fixed at a specific temperature in cooperation with independent temperature control, and is cooperatively locked. But the existing high-quality temperature control cannot ensure that the frequency drift is within the PZT locking range. According to the invention, the PZT and the temperature control are used for cooperative control, so that the range of the optical frequency comb repetition frequency locking is greatly enlarged, and the long-time locking is realized; meanwhile, by slowly changing the temperature control set value, the working voltage of the PZT is stabilized near a certain specific value, the locking result of the PID is not affected by the nonlinearity of the PZT response curve, and the quality of loading the reference frequency signal onto the optical frequency comb is improved.
Drawings
Fig. 1 is a schematic diagram of the system structure of the present invention.
Detailed Description
In order to make the above features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.
FIG. 1 is a flow chart of an optical frequency comb repetition frequency locking method based on temperature control and piezoelectric ceramics, which comprises the following steps:
1) Taking an optical frequency comb with a repetition frequency of 100MHz as an example, the frequency of the reference signal may be an integer multiple of 100 MHz. And connecting the outputs of the reference signal and the optical frequency comb to a frequency error signal generating module to obtain the difference between the reference signal and the optical frequency comb. If the phase demodulation is performed by using the frequency mixing device, the output of the laser needs to be subjected to photoelectric conversion, and the output is filtered by using a band-pass filter with the same frequency as the reference signal, and then the phase demodulation is performed by frequency mixing; if optical-microwave phase discrimination is used, the optical signal can be directly connected to the module. Whichever phase discrimination method is used, a low pass filter is connected to the output to filter out high frequency components in the signal.
2) And (3) connecting the error signal obtained in the steps into a high-speed servo control module to perform feedback control. The output is amplified by a voltage control module, and piezoelectric ceramics (PZT) in the mode-locked laser is controlled to adjust the length of the space light part, so that the optical comb repetition frequency is dynamically adjusted.
3) Meanwhile, the input of the voltage control module is also connected with the low-speed servo feedback control module for controlling the temperature control module. The low speed servo feedback control module sets the input bias as needed to set the PZT operating voltage at that point.
4) The low-speed servo feedback control module calculates the temperature adjustment quantity of the optical fiber in the resonant cavity of the mode-locked laser according to the input voltage signal and the current regulation voltage value of the piezoelectric ceramic controller; and the output of the low-speed servo feedback control module is connected to the temperature control module to control the temperature set value. When the PZT voltage deviates from a set value, the temperature control module regulates and controls the temperature of the optical fiber in the resonant cavity according to the optical fiber temperature regulating quantity, so that the PZT voltage is maintained near the set value.
5) By using the steps, the problem that the optical frequency comb repetition frequency cannot be locked for a long time and a series of problems brought by the nonlinearity of the PZT response curve are solved.
The above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and those skilled in the art may modify or substitute the technical solution of the present invention without departing from the spirit and scope of the present invention, and the protection scope of the present invention shall be subject to the claims.

Claims (5)

1.一种基于温控和压电陶瓷的光学频率梳重复频率锁定方法，其步骤包括：1. A method for locking the repetition frequency of an optical frequency comb based on temperature control and piezoelectric ceramics, the steps comprising: 1)将参考频率信号与锁模激光器输出的光学频率梳接入频率误差信号产生模块，得到光学频率梳的重复频率与参考频率之差作为误差信号输入高速伺服控制模块；1) Connecting the reference frequency signal and the optical frequency comb output by the mode-locked laser to the frequency error signal generation module, and obtaining the difference between the repetition frequency of the optical frequency comb and the reference frequency as the error signal to input into the high-speed servo control module; 2)高速伺服控制模块根据输入的所述误差信号生成反馈控制信号并输入到电压控制模块；2) The high-speed servo control module generates a feedback control signal according to the input error signal and inputs the feedback control signal to the voltage control module; 3)电压控制模块根据所述反馈控制信号生成目标电压信号并将其分别输入到所述锁模激光器中的压电陶瓷和低速伺服反馈控制模块，用于对所述光学频率梳的重复频率进行动态调节；3) A voltage control module generates a target voltage signal according to the feedback control signal and inputs the target voltage signal to the piezoelectric ceramic and low-speed servo feedback control modules in the mode-locked laser, respectively, for dynamically adjusting the repetition frequency of the optical frequency comb; 4)所述压电陶瓷根据所述目标电压信号调控所述锁模激光器的腔长；在低速伺服反馈控制模块设置目标电压，即电压控制模块输出的目标电压，并在开始反馈前，将温控的偏置温度设置为当前温度；开始反馈控制温控的设定温度，当所述压电陶瓷施加的电压偏离设定的目标电压时，调节温控的设定温度，使所述压电陶瓷的电压在保证频率锁定的基础上，维持在一定范围内不变；所述低速伺服反馈控制模块根据所述目标电压信号、压电陶瓷控制器当前的调控电压值计算所述锁模激光器的谐振腔中光纤温度调节量；所述锁模激光器的温度控制器根据所述光纤温度调节量调控谐振腔中光纤温度4) The piezoelectric ceramic controls the cavity length of the mode-locked laser according to the target voltage signal; sets the target voltage in the low-speed servo feedback control module, that is, the target voltage output by the voltage control module, and sets the bias temperature of the temperature control to the current temperature before starting feedback; starts feedback control of the set temperature of the temperature control, and when the voltage applied by the piezoelectric ceramic deviates from the set target voltage, adjusts the set temperature of the temperature control so that the voltage of the piezoelectric ceramic is maintained unchanged within a certain range while ensuring frequency locking; the low-speed servo feedback control module calculates the fiber temperature adjustment amount in the resonant cavity of the mode-locked laser according to the target voltage signal and the current control voltage value of the piezoelectric ceramic controller; the temperature controller of the mode-locked laser adjusts the fiber temperature in the resonant cavity according to the fiber temperature adjustment amount 5)通过反馈调整温控，实现光梳激光器重频的长时间锁定。5) By adjusting the temperature control through feedback, the long-term locking of the repetition rate of the optical comb laser can be achieved. 2.根据权利要求1所述的方法，其特征在于，所述低速伺服反馈控制模块监控压电陶瓷控制器当前的调控电压值，当调控电压值偏离目标电压时，根据电压偏离值计算所述锁模激光器的谐振腔中光纤温度调节量；然后所述锁模激光器的温度控制器根据所述光纤温度调节量调控谐振腔中光纤温度。2. The method according to claim 1 is characterized in that the low-speed servo feedback control module monitors the current control voltage value of the piezoelectric ceramic controller. When the control voltage value deviates from the target voltage, the fiber temperature adjustment amount in the resonant cavity of the mode-locked laser is calculated according to the voltage deviation value; then the temperature controller of the mode-locked laser controls the fiber temperature in the resonant cavity according to the fiber temperature adjustment amount. 3.根据权利要求1或2所述的方法，其特征在于，所述频率误差信号产生模块为混频设备鉴相器，则所述锁模激光器输出的光学频率梳进行光电转换，并使用与所述参考频率信号同频的带通滤波器滤波后输入到所述混频设备鉴相器。3. The method according to claim 1 or 2 is characterized in that the frequency error signal generating module is a phase detector of a frequency mixing device, and the optical frequency comb output by the mode-locked laser is subjected to photoelectric conversion, and is filtered using a bandpass filter with the same frequency as the reference frequency signal and then input into the phase detector of the frequency mixing device. 4.根据权利要求1或2所述的方法，其特征在于，所述频率误差信号产生模块为光-微波鉴相器，所述锁模激光器输出的光学频率梳直接输入到所述光-微波鉴相器。4. The method according to claim 1 or 2, characterized in that the frequency error signal generating module is an optical-microwave phase detector, and the optical frequency comb output by the mode-locked laser is directly input into the optical-microwave phase detector. 5.根据权利要求1所述的方法，其特征在于，所述参考频率信号的频率为所述光学频率梳的重复频率的整数倍。5 . The method according to claim 1 , wherein the frequency of the reference frequency signal is an integer multiple of the repetition frequency of the optical frequency comb.
CN202210215550.XA 2022-03-07 2022-03-07 A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics Active CN114709708B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210215550.XA CN114709708B (en) 2022-03-07 2022-03-07 A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210215550.XA CN114709708B (en) 2022-03-07 2022-03-07 A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics

Publications (2)

Publication Number Publication Date
CN114709708A CN114709708A (en) 2022-07-05
CN114709708B true CN114709708B (en) 2024-06-28

Family

ID=82166184

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210215550.XA Active CN114709708B (en) 2022-03-07 2022-03-07 A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics

Country Status (1)

Country Link
CN (1) CN114709708B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115912037A (en) * 2022-09-26 2023-04-04 北京航天计量测试技术研究所 Optical frequency comb repetition frequency locking method and device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105826804A (en) * 2016-05-27 2016-08-03 清华大学 Light frequency reference fiber femtosecond light frequency comb with tunable broadband repetition frequency
CN108593110A (en) * 2018-05-08 2018-09-28 天津大学 All -fiber Fourier transform spectrometer, based on PZT phase-modulation real-time compensations

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4844405B2 (en) * 2007-01-24 2011-12-28 沖電気工業株式会社 Optical clock signal regenerator
US20150003834A1 (en) * 2013-07-01 2015-01-01 Xuekang Shan Brillouin Strain and Temperature sensor incorporating a frequency offset locked DFB laser pair
US10326251B2 (en) * 2015-06-08 2019-06-18 University Of Central Florida Research Foundation, Inc. Ultra-low noise mode-locked laser, methods, and applications
CN105890780B (en) * 2016-04-08 2019-01-25 淄博齐瑞德光电技术有限公司 It is a kind of for locking the optical microwave frequency discriminator and method of laser difference frequency
CN113206434B (en) * 2021-05-07 2022-08-02 北京邮电大学 Pre-compensation feedback control system and method for frequency difference locking of fiber laser
CN113823991B (en) * 2021-06-01 2022-10-11 中国科学院国家授时中心 Locking method and locking circuit of optical frequency comb

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105826804A (en) * 2016-05-27 2016-08-03 清华大学 Light frequency reference fiber femtosecond light frequency comb with tunable broadband repetition frequency
CN108593110A (en) * 2018-05-08 2018-09-28 天津大学 All -fiber Fourier transform spectrometer, based on PZT phase-modulation real-time compensations

Also Published As

Publication number Publication date
CN114709708A (en) 2022-07-05

Similar Documents

Publication Publication Date Title
CN102629731B (en) Control method for simultaneously stabilizing laser wavelength and power and control device thereof
CN105826804B (en) A kind of repetition rate can wide-band tuning optical frequency reference optical fiber femtosecond optical frequency comb
CN104638501A (en) Small-size optical fiber femtosecond laser with wide repetition frequency tuning range
CN112925122B (en) Silicon-based Mach-Zehnder modulator bias control device and system based on pilot frequency method
CN114709708B (en) A method for locking the repetition rate of an optical frequency comb based on temperature control and piezoelectric ceramics
CN106099638A (en) A kind of Distributed Feedback Laser frequency-stabilizing method controlled based on electric current
CN108471045B (en) Laser constant power digital control method and system
CN112240765B (en) Precise closed-loop control device for transition time of fiber-optic gyroscope
CN116387956B (en) PDH technology-based laser digital frequency locking main control module and digital frequency locking system
CN114300927B (en) Self-adaptive beat frequency locking system of fiber laser
CN105762635B (en) A kind of wavelength control apparatus and method of adjustable light module
CN104953459B (en) A kind of transmission cavity frequency stabilization system that laser frequency is steady in a long-term and its frequency-stabilizing method
CN103872570A (en) Ytterbium-doped optical fiber mode-locked laser phase locking method
CN107317220B (en) A precision laser frequency stabilization power supply based on ultra-stable F-P cavity
US12424814B2 (en) Method and device for automatically locking repetition frequency and carrier-envelop offset frequency of optical frequency comb
CN116224788A (en) A model reference adaptive anti-disturbance optimal control method
CN111600189B (en) Pump Seed Synchronization System and Method Based on Ultrashort Pulse Optical Parametric Amplification
EP3095163B1 (en) Serial servo system and method for controlling an optical path length and a repetition frequency of a mode-locked laser
CN115220512B (en) Automatic phase-locking constant current source circuit and method for driving tunable laser
CN119401987A (en) A high-precision delay synchronization system with phase jitter compensation function
CN213659093U (en) Real-time Active Optical Phase Locking System
CN115290061B (en) Digital saturated absorption frequency stabilization control system of SERF gyroscope
CN113471806B (en) Multi-feedback laser stepping frequency sweep driving device and method
CN114205003B (en) A fast and slow loop combined feedback control system and method for locking the frequency difference signal between signal light and local oscillator light over an optical fiber link
CN118174718A (en) A crystal oscillator taming system and method based on satellite timing

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant