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CN-122026207-A - Double-ring photoelectric oscillator and stabilizing method thereof

CN122026207ACN 122026207 ACN122026207 ACN 122026207ACN-122026207-A

Abstract

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator and a stabilizing method thereof; the oscillator is provided with a long loop and a short loop and comprises a stabilizing device, the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher and a motor space optical delay line, the second piezoelectric ceramic optical fiber stretcher generates two optical probe signals, the first optical probe signals are converted into first electric probe signals through the long loop, the second optical probe signals are converted into second electric probe signals through the short loop, the electric probe signals are output after detection, coupling and power division, the two mixers respectively carry out homodyne frequency mixing on the electric probe signals and the radio frequency signals which are phase-shifted and not phase-shifted to generate zero frequency error signals, the two phase-locked loops generate compensation control signals according to the error signals, the control signals adjust the optical fiber delay line, the stability of the two loops is guaranteed, the frequency drift of a combined signal caused by neglecting the delay change of the short loop is solved, the coherent requirements of the optical signals are eliminated through the electric domain combining, and the smooth tuning of the frequency of the output radio frequency signals is realized.

Inventors

  • WEI WEI
  • ZHU XINYU
  • DONG YI

Assignees

  • 北京理工大学

Dates

Publication Date
20260512
Application Date
20251223

Claims (10)

  1. 1. The double-ring photoelectric oscillator is provided with a long ring and a short ring, and is characterized by further comprising a stabilizing device, wherein the stabilizing device comprises: The first piezoelectric ceramic optical fiber stretcher and the motor space light delay line form a cascade structure connected to the long ring; The second piezoelectric ceramic optical fiber stretcher is connected to the short ring; The system comprises a long loop, a radio frequency signal source, a short loop, a first photoelectric detector, a second photoelectric detector, a first optical probe signal source, a second optical probe signal source and a second optical probe signal source, wherein the long loop is connected with the first optical probe signal source; The first mixer is used for carrying out homodyne mixing on the first electric probe signal and the radio frequency signal subjected to phase shifting of the adjustable electric phase shifter to generate a first zero frequency error signal; the second mixer is used for carrying out homodyne mixing on the second electric probe signal and the radio frequency signal to generate a second zero frequency error signal; The first phase-locked loop is used for processing the first zero frequency error signal and generating a first compensation control signal for controlling a cascade structure formed by the first piezoelectric ceramic optical fiber stretcher and the motor space optical delay line; and the second phase-locked loop is used for processing the second zero frequency error signal and generating a second compensation control signal for controlling the second piezoelectric ceramic optical fiber stretcher.
  2. 2. The dual-ring optoelectronic oscillator of claim 1, wherein the frequency range of the radio frequency signal source is 22 ghz-28 ghz.
  3. 3. The dual ring optoelectronic oscillator of claim 2 wherein the frequency of the radio frequency signal source is 26 GHz.
  4. 4. The dual ring optoelectronic oscillator of claim 1, wherein the length of the long ring optical fiber is 2km to 100km.
  5. 5. The dual ring optoelectronic oscillator of claim 4 wherein the length of the long ring optical fiber is 10km.
  6. 6. The dual-ring optoelectronic oscillator of claim 1, further comprising a laser, a bias point control unit, and an optocoupler, wherein the laser is input to the forcing modulator via an optical connection, the bias point control unit is input to the intensity modulator via an electrical connection, the intensity modulator is input to the optocoupler via an optical connection, and the optocoupler is optically connected to the long ring and the short ring.
  7. 7. The dual-ring optoelectronic oscillator of claim 6, wherein the first and second photodetectors are input to a first electrical coupler via an electrical connection, the first electrical coupler is input to a first power amplifier via an electrical connection, the first power amplifier is input to a bandpass filter via an electrical connection, the bandpass filter is input to a first power divider via an electrical connection, the first power divider is input to the second electrical coupler via an electrical connection, the second electrical coupler is input to the intensity modulator via an electrical connection, the radio frequency signal source is input to the second electrical coupler via an electrical connection, and the second electrical coupler is input to the intensity modulator via an electrical connection.
  8. 8. The dual-ring photoelectric oscillator according to claim 7, wherein a second power amplifier is arranged between the first photoelectric detector and the first mixer, and a third power amplifier is arranged between the second photoelectric detector and the second mixer.
  9. 9. The dual-ring optoelectronic oscillator of claim 8, wherein the radio frequency signal source is input to a second power divider via an electrical connection, the second power divider being input to the first and second mixers, respectively, via an electrical connection.
  10. 10. A method of stabilizing a dual ring optoelectronic oscillator as claimed in any one of claims 1 to 9 comprising the steps of: The method comprises the steps of enabling a radio frequency signal source to generate a radio frequency signal, enabling the radio frequency signal to generate a first optical probe signal injected into a long loop and a second optical probe signal injected into a short loop through controlling an intensity modulator, enabling the first optical probe signal to be converted into a first electrical probe signal carrying long loop delay jitter information through a first photoelectric detector after passing through the long loop, and enabling the second optical probe signal to be converted into a second electrical probe signal carrying short loop delay jitter information through a second photoelectric detector after passing through the short loop; Carrying out homodyne frequency mixing on the first electric probe signal and the radio frequency signal subjected to phase shifting of the adjustable electric phase shifter through a first frequency mixer to generate a first zero frequency error signal with an adjustable phase locking state; Performing homodyne frequency mixing on the second electric probe signal and the radio frequency signal through a second frequency mixer to generate a second zero frequency error signal; Processing the first zero frequency error signal through a first phase-locked loop and generating a first compensation control signal for controlling a cascade structure formed by the first piezoelectric ceramic optical fiber stretcher and the motor space optical delay line; processing the second zero frequency error signal through a second phase-locked loop and generating a second compensation control signal for controlling the compensation of the second piezoelectric ceramic optical fiber stretcher; By compensating for the fiber delays of the long loop and the short loop, a frequency stable and tunable radio frequency output signal is generated.

Description

Double-ring photoelectric oscillator and stabilizing method thereof Technical Field The invention belongs to the technical field of microwave photons, and particularly relates to a double-ring photoelectric oscillator and a stabilizing method thereof. Background The microwave photon technology is a cross technology for realizing the functions of generating, distributing, controlling, processing and the like of microwave signals by utilizing the photon technology, and is widely used for solving the problem of limitation faced by the current microwave field. The photo-generated microwave technology is an important aspect of microwave photonics and is used for generating high-quality microwave signals so as to overcome the defects of traditional microwave signal sources, such as an electric oscillator and the like in terms of bandwidth, stability and noise performance and meet the increasingly improved index requirements of a microwave system. The current common photo-generated microwave method is mainly generated by optical heterodyne, electro-optic modulation, photoelectric oscillator and the like. The photoelectric oscillator generates a microwave signal based on a photoelectric positive feedback loop, oscillates a mode exceeding a gain threshold and meeting phase conditions in the loop into a high-power signal based on the high energy storage property of an optical fiber, and the phase noise can be superior to other photo-generated microwave technologies and is not influenced by frequency change, so that the strict requirements on the performance of the high-frequency signal in the fields such as sensing, radar and the like can be met. In short, a method of generating microwaves by using a photoelectric oscillator generates high-quality microwave signals with low phase noise and high spectral purity by using the characteristics of a high-Q value energy storage device and a positive feedback loop, and the method is a technology which is widely focused in the field of photo-generated microwaves. For the photoelectric oscillator, the most remarkable advantage is low phase noise based on the long optical fiber, but the long optical fiber is very easy to be influenced by environmental factors such as external temperature, stress and the like, so that jitter occurs in transmission delay, and the long-term stability of output frequency is further influenced. And because the long optical fiber can lead to smaller free spectral range, the electric band-pass filter generated by the prior art can not select a single mode, thereby leading to disordered output frequency and further deteriorating long-term stability due to mode-jump. To overcome the problem of multimode output, the current common solutions include improving the structure and optimizing the device, wherein the improving structure direction mainly includes multi-loop design, injection locking, and the like. The dual-ring photoelectric oscillator structure proposed by Steve Yao in 1998 and the improved optical domain dual-ring structure proposed by Yang Jiang in 2007 realize mode selection based on vernier caliper effect, thereby obtaining a single-mode output signal. The injection locking structure proposed in 2008 Weimin Zhou additionally improves the energy of the required frequency by feeding an external signal source, thereby realizing single-mode output through mode traction. Meanwhile, in order to solve the stability problem, it is proposed to use temperature control and phase-locked loop technology, etc. In 2003D Eliyahu, etc., a temperature control device is used for improving the stability of the photoelectric oscillator, but the precision is lower and the response speed is slower. The phase-locked loop technology is used as an excellent phase negative feedback technology, and can realize the phase stabilization of signals with higher precision. 2021 year Huanfa Peng proposes a system for improving stability of a photoelectric oscillator with a dual-loop structure matched with a phase-locked loop, but only realizes phase locking for a long loop, ignores frequency jitter caused by changes of a short loop due to factors such as ambient temperature, and the like, so that long-term stability of a combined output signal is deteriorated. The patent issued by 2024 Bao Chengcheng et al proposes a structure using double-loop phase locking, but uses an electric phase shifter as a compensation device, which has low accuracy and limited output tuning capability. Disclosure of Invention The invention provides a double-ring photoelectric oscillator and a stabilizing method thereof, so as to at least partially solve the technical problems. As a first aspect of the present invention, there is provided a dual-ring optoelectronic oscillator having a long ring and a short ring, the dual-ring optoelectronic oscillator further comprising a stabilizing device, the stabilizing device comprising: The first piezoelectric ceramic optical fiber stretcher and the motor spac