CN-116886206-B - Parameter configuration method of optical frequency comb repetition frequency multiplication device and photon frequency integrated system

CN116886206BCN 116886206 BCN116886206 BCN 116886206BCN-116886206-B

Abstract

The invention relates to a parameter configuration method of an optical frequency comb repetition frequency multiplication device and a photon frequency integrated system, wherein the parameter configuration method comprises the following steps: setting a required optical frequency comb repetition frequency harmonic component and a required spurious suppression lower limit, and optimally configuring the number of stages of the asymmetric Mach-Zehnder interference optical paths and parameters of each stage of the asymmetric Mach-Zehnder interference optical paths according to spurious suppression. According to the invention, the optical frequency comb repetition frequency multiplication device adopts the structure of the MZ I interference type optical pulse repetition frequency multiplier, can enhance the radio frequency power of the required optical frequency comb repetition frequency harmonic component and inhibit other harmonic components, and optimally configures the parameters of the optical frequency comb repetition frequency multiplication device according to the spurious suppression requirement, so that the optical frequency comb repetition frequency multiplication device works in an optimal state, thereby expanding the application range of the MZ I interference type optical pulse repetition frequency multiplier.

Inventors

ZHANG HAO
GAO SHUAIHE
Yan Yingxing
ZHANG SHOUGANG
QU PENGFEI

Assignees

中国电子科技集团公司第四十四研究所
中国科学院国家授时中心

Dates

Publication Date: 20260512
Application Date: 20230808

Claims (10)

1. A parameter configuration method of an optical frequency comb repetition frequency multiplication device is characterized in that the optical frequency comb repetition frequency multiplication device comprises n stages of asymmetric Mach-Zehnder interference light paths connected in a cascading mode, wherein n is an integer greater than or equal to 1, and the parameter configuration method comprises the following steps: s1, setting an initial series n=1 of an asymmetric Mach-Zehnder interference optical path; S2, setting a required optical frequency comb repetition frequency harmonic component f s and a required spurious suppression lower limit L, and setting a plurality of optical frequency comb repetition frequency harmonic components f k which are taken into consideration in the spurious suppression of f s , wherein f s =s·f 0 ,f k =k·f 0 , S and k are integers, and S is not equal to k, The frequency is the repetition frequency of the optical frequency comb; S3, acquiring a frequency transfer function H (omega) of each level of unit of the system equipment at the rear end; S4, determining boundaries of parameters k, alpha i and delta tau j , wherein alpha i represents the splitting ratio of an ith-stage asymmetric Mach-Zehnder interference optical path, delta tau j represents the two-arm optical path delay difference of a jth-stage asymmetric Mach-Zehnder interference optical path, i is more than or equal to 1 and less than or equal to n, and j is more than or equal to 1 and less than or equal to n; S5, traversing the values of the parameters alpha i and delta tau i , and calculating the minimum value F of spurious suppression at each F k for each group of alpha i and delta tau i by adopting the following formula: s6, if the max (F) is not less than L, executing the step S7, otherwise, adding 1 to the value of the series n of the asymmetric Mach-Zehnder interference light path, and returning to execute the step S5; S7, acquiring the value of n and the values of alpha i and delta tau j corresponding to max (F) at the moment as parameters of the optical frequency comb repetition frequency multiplication device, and ending the configuration.
2. The method of claim 1, wherein when the number of the required repetition frequency harmonic components F s in the step S2 is more than one, in the step S5, for each of the groups of values α i and Δτ j , the F value corresponding to each of the F s is calculated, and the minimum value is taken as the F value corresponding to the groups of values α i and Δτ j .
3. The method according to claim 1, wherein in the step S4, the boundaries of the parameters k, α i and Δτ j are determined as follows: 1≤k≤+∞; 0≤α i ≤1; 0≤Δτ j ≤1/f 0 。
4. The method for configuring parameters of an optical frequency comb multiple frequency multiplication device according to any one of claims 1 to 3, wherein the n-stage asymmetric Mach-Zehnder interference optical path connected in a cascading manner comprises (n+1) stages of optical couplers connected in an optical fiber cascade manner, the first-stage optical coupler is a1×2 optical coupler or a2×2 optical coupler, the last-stage optical coupler is a2×1 optical coupler or a2×2 optical coupler, the rest optical couplers are all 2×2 optical couplers, the 1×2 optical coupler has one input end and two output ends, the 2×2 optical coupler has two input ends and two output ends, and the 2×1 optical coupler has two input ends and one output end.
5. The method for configuring parameters of an optical frequency comb repetition frequency multiplication device according to claim 4, wherein the input end of the first-stage optical coupler is used as the input end of the optical frequency comb repetition frequency multiplication device for connecting an optical frequency comb; The two input ends of the final-stage optical coupler are respectively connected with the two output ends of the front-stage optical coupler through optical fibers, and the output end of the final-stage optical coupler is used as the output end of the optical frequency comb repetition frequency multiplication device for connecting with system equipment at the rear end; When n is more than or equal to 2, the two input ends of each stage of 2X 2 optical coupler between the first stage and the last stage are respectively connected with the two output ends of the previous stage of optical coupler through optical fibers.
6. The method for configuring parameters of an optical frequency comb multiple frequency multiplication device according to claim 5, wherein the 1×2 optical coupler comprises a first "Y" branch waveguide for branching and two first output arms respectively connected to two output ends of the first "Y" branch waveguide, an input end of the first "Y" branch waveguide is an input end of the 1×2 optical coupler, and non-connection ends of the two first output arms are two output ends of the 1×2 optical coupler; The 2X 2 optical coupler comprises a second Y-branch waveguide used for combining and a third Y-branch waveguide used for branching, wherein two input ends of the second Y-branch waveguide are respectively connected with a second input arm, the output end of the second Y-branch waveguide is connected with the input end of the third Y-branch waveguide, two output ends of the third Y-branch waveguide are respectively connected with a second output arm, the non-connection ends of the two second input arms are two input ends of the 2X 2 optical coupler, and the non-connection ends of the two second output arms are two output ends of the 2X 2 optical coupler; the 2X 1 optical coupler comprises a fourth Y-branch waveguide for combining and two first input arms respectively connected with two input ends of the fourth Y-branch waveguide, wherein the non-connection ends of the two first input arms are two input ends of the 2X 1 optical coupler, and the output end of the fourth Y-branch waveguide is the output end of the 2X 1 optical coupler.
7. The method of configuring parameters of an optical frequency comb multiple frequency multiplication apparatus according to claim 6, wherein when n=1 and the first-stage optical coupler is a1×2 optical coupler and the second-stage optical coupler is a 2×1 optical coupler, the first-stage asymmetric Mach-Zehnder interference optical path includes the 1×2 optical coupler, the 2×1 optical coupler, and an optical fiber connecting two first output arms of the 1×2 optical coupler and two first input arms of the 2×1 optical coupler.
8. The method for configuring parameters of an optical frequency comb multiple frequency multiplication device according to claim 6, wherein when the first-stage optical coupler is a1×2 optical coupler and the second-stage optical coupler is a2×2 optical coupler, the first-stage asymmetric Mach-Zehnder interference optical path comprises the 1×2 optical coupler, a second "Y" branch waveguide and two second input arms in the 2×2 optical coupler cascaded therewith, and an optical fiber connecting the two second input arms of the 2×2 optical coupler and the two first output arms of the 1×2 optical coupler; When the first-stage optical coupler and the second-stage optical coupler are both 2×2 optical couplers, the first-stage asymmetric mach-zehnder interference optical path includes a third "Y" branch waveguide and two second output arms in the first-stage 2×2 optical coupler, a second "Y" branch waveguide and two second input arms in the second-stage 2×2 optical coupler, and an optical fiber between the two second input arms of the second-stage 2×2 optical coupler and the two second output arms of the first-stage 2×2 optical coupler; When the final-stage optical coupler is a 2×1 optical coupler and the previous-stage optical coupler is a 2×2 optical coupler, the final-stage asymmetric mach-zehnder interference optical path comprises the 2×1 optical coupler, a third 'Y' branch waveguide and two second output arms in the 2×2 optical coupler cascaded with the 2×1 optical coupler, and optical fibers connected between the two first input arms of the 2×1 optical coupler and the two second output arms of the 2×2 optical coupler; When the last-stage optical coupler and the preceding-stage optical coupler are both 2×2 optical couplers, the last-stage asymmetric mach-zehnder interference optical path includes a second "Y" branch waveguide and two second input arms in the last-stage 2×2 optical coupler, a third "Y" branch waveguide and two second output arms in the preceding-stage 2×2 optical coupler, and an optical fiber connecting between the two second input arms of the last-stage 2×2 optical coupler and the two second output arms of the preceding-stage 2×2 optical coupler.
9. The method of configuring parameters of an optical frequency comb multiple frequency multiplication apparatus according to claim 8, wherein when n is equal to or greater than 3, each of the asymmetric Mach-Zehnder interference optical paths between the first stage and the last stage includes a third "Y" branch waveguide and two second output arms in the previous stage 2×2 optical coupler, a second "Y" branch waveguide and two second input arms in the subsequent stage 2×2 optical coupler, and an optical fiber between the two second input arms of the subsequent stage 2×2 optical coupler and the two second output arms of the previous stage 2×2 optical coupler, respectively.
10. The femtosecond photon frequency integrated system based on the optical frequency comb is characterized by comprising the optical frequency comb, wherein the output end of the optical frequency comb is connected with the optical frequency comb repetition frequency multiplication device which is configured by adopting the parameter configuration method of the optical frequency comb repetition frequency multiplication device according to any one of claims 1-9, the output end of the optical frequency comb repetition frequency multiplication device is connected with system equipment, and the system equipment is used for carrying out photoelectric conversion on an output signal of the optical frequency comb repetition frequency multiplication device, and processing an optical signal before photoelectric conversion and/or a signal after photoelectric conversion to obtain a required frequency when the photoelectric conversion cannot meet the requirement.

Description

Parameter configuration method of optical frequency comb repetition frequency multiplication device and photon frequency integrated system Technical Field The invention belongs to the technical field of microwave photons, and relates to a parameter configuration method of an optical frequency comb repetition frequency multiplication device and a photon frequency comprehensive system. Background The optical frequency comb is formed by a series of equally spaced frequency comb teeth in frequency spectrum, and becomes one of the most popular research directions in the optical field in the last ten years. The concept of optical frequency comb has been proposed so far, and the generation methods can be roughly classified into a mode-locked laser method, a cyclic frequency shifter method, an optical fiber nonlinear effect method and an external modulator method according to the generation principle thereof. The optical frequency comb has the advantages of large bandwidth, high stability, rich frequency spectrum and the like, and has important application value in the fields of satellite navigation, aerospace, deep space exploration, reconnaissance and early warning and the like. The frequency synthesis technology based on the optical frequency comb can be used for generating various microwave frequency signals, and the signals generated by the technology can break through the key technical index bottlenecks such as phase noise, frequency stability and the like. Because the repetition frequency of the high-performance optical frequency comb optical pulse signal source is low, the high-frequency signal generation often needs the process of repetition frequency multiplication, and the MZI interference type optical pulse repetition frequency multiplier has high conversion efficiency and small optical power loss, and is one of common means. Because the pulse width of the optical pulse signal is extremely narrow, the instantaneous peak power is extremely high, and meanwhile, the optical pulse frequency spectrum component is abundant, and the optical detector works in a saturated state in the photoelectric conversion process, the photoelectric conversion output microwave frequency signal power and the harmonic clutter suppression capability are limited. Therefore, the MZI interference type optical pulse repetition frequency multiplier needs to work in an optimal state. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a parameter configuration method and a photon frequency integrated system of an optical frequency comb repetition frequency multiplication device. In order to achieve the above purpose, the present invention provides the following technical solutions: The parameter configuration method of the optical frequency comb repetition frequency multiplication device comprises n stages of asymmetric Mach-Zehnder interference light paths connected in a cascading mode, wherein n is an integer greater than or equal to 1, and the parameter configuration method comprises the following steps of: s1, setting an initial series n=1 of an asymmetric Mach-Zehnder interference optical path; S2, setting a required optical frequency comb repetition frequency harmonic component f s and a required spurious suppression lower limit L, and setting a plurality of optical frequency comb repetition frequency harmonic components f k which are near f s and take into consideration spurious suppression, wherein f s=s·f0,fk=k·f0, S and k are integers, and S is not equal to k, The frequency is the repetition frequency of the optical frequency comb; S3, acquiring a frequency transfer function H (omega) of each level of unit of the system equipment at the rear end; S4, determining boundaries of parameters k, alpha i and delta tau j, wherein alpha i represents the splitting ratio of an ith-stage asymmetric Mach-Zehnder interference optical path, delta tau j represents the two-arm optical path delay difference of a jth-stage asymmetric Mach-Zehnder interference optical path, i is more than or equal to 1 and less than or equal to n, and j is more than or equal to 1 and less than or equal to n; S5, traversing the values of the parameters alpha i and delta tau i, and calculating the minimum value F of spurious suppression at each F k for each group of alpha i and delta tau i by adopting the following formula: s6, if the max (F) is not less than L, executing the step S7, otherwise, adding 1 to the value of the series n of the asymmetric Mach-Zehnder interference light path, and returning to execute the step S5; S7, acquiring the value of n and the values of alpha i and delta tau j corresponding to max (F) at the moment as parameters of the optical frequency comb repetition frequency multiplication device, and ending the configuration. Further, when the number of the required heavy frequency harmonic components F s in the step S2 is more than one, in the step S5, for each group of values of α i and Δτ j, F va