CN109067469A - A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation - Google Patents
A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation Download PDFInfo
- Publication number
- CN109067469A CN109067469A CN201811133993.4A CN201811133993A CN109067469A CN 109067469 A CN109067469 A CN 109067469A CN 201811133993 A CN201811133993 A CN 201811133993A CN 109067469 A CN109067469 A CN 109067469A
- Authority
- CN
- China
- Prior art keywords
- signal
- multifrequency
- modulation
- frequency
- optical fiber
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/572—Wavelength control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/501—Structural aspects
- H04B10/503—Laser transmitters
- H04B10/505—Laser transmitters using external modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
- H04B10/548—Phase or frequency modulation
- H04B10/556—Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK]
- H04B10/5561—Digital phase modulation
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
- Optical Communication System (AREA)
Abstract
The present invention provides a kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation, belongs to optical technical field.Laser frequency shifter of the present invention includes laser source, electrooptic modulator, bandpass filter, spectral measurement system, arbitrary waveform generator and the radio frequency signal amplifiers of narrow linewidth；The method of the present invention includes: that the simple signal that the laser source of narrow linewidth exports is imported into electrooptic modulator first；It is then based on spectrum analysis retrospectively calculate and obtains multifrequency modulation signal waveform, setting arbitrary waveform generator generates corresponding multifrequency modulation signal；Modulation signal first passes through radio frequency signal amplifiers and amplifies, and is transmitted to electrooptic modulator；The optical signal formed after modulation is output to bandpass filter and carries out shift frequency；Last spectral measurement system carries out spectral composition analysis.The present invention solves the problems, such as that the power utilization of prior art signal is not high, device structure is more complex.The present invention can operate with wireless communication and Fibre Optical Sensor.
Description
Technical field
The present invention relates to a kind of laser frequency shifter and frequency shift methods, belong to optical technical field.
Background technique
Distributed fiberoptic sensor on entire continuous optical fiber, can measure the temperature of optical fiber axial direction each position, strain, micro-
Vibration etc. parameters, it is for point type fibre optical sensor, either from the difficulty of measuring technique, or from measurement occasion and
Range has all been increased to a new stage.Distributed Brillouin light fiber sensor is one such, wherein single-frequency pump light
It is incident in optical fiber with signal light from sensor fibre both ends, the difference on the frequency between signal light and pump light meets the Brillouin in optical fiber
When frequency displacement, stimulated Brillouin scattering (Stimulated Brillouin scattering, SBS) effect will occur and be amplified.
Temperature, the strain etc. of the Brillouin shift of every bit and the position have direct relationship in optical fiber.Therefore, every in optical fiber axial direction
Some the Brillouin shift of the position can be obtained by the frequency of scanning signal light, obtain position temperature, the strain etc. indirectly
Difference between parameter and under natural conditions representative value.To realize the distribution to the physical quantitys such as temperature on whole optical fiber and strain
Measurement.
An important link in this distributed fiberoptic sensor design process is how to obtain the adjustable letter of frequency
Number light realizes the scanning of every bit brillouin gain spectrum in optical fiber.Therefore, an adjustable laser frequency displacement being simple and efficient is designed
Device (Frequency shifter, FS) is the premise for realizing distributing optical fiber sensing.
Currently, the method for realizing the frequency shifts of laser can be attributed to three classes according to its realization principle: (1) using phase
Position modulator obtains the adjustable light double-sideband of frequency interval (Optical double sideband, ODSB) modulated signal, then
A sideband in ODSB signal is filtered out using optical filter, obtains FS signal；(2) amplify a sideband in ODSB, obtain
Obtain the output of FS signal；(3) FS letter is directly obtained using optical SSB (Optical single sideband, OSSB) modulator
Number.
2005, Spain Capmany et al. was generated using concatenated two groups of fiber bragg grating arrays (FBGA)
The OSSB signal of multi-wavelength.The optical-fiber laser that multi-wavelength is generated by tunable fiber laser array, is injected into Electro-optical Modulation
In device, it is modulated into double-side band laser signal in length and breadth by each, then filters out one of sideband using FBGA, obtains multi-wavelength
OSSB signal.This method insertion loss, carrier wave resist effect, in terms of have preferable performance.As long as using high
The frequency range of the FBG filter of quality, high reflectance, application can extend to entire Microwave bandwidth range from millimeter wave.
2012, Tang et al. generated ODSB signal using phase-modulator, then utilizes a tunable, filters out it
In a sideband, obtain OSSB signal.And be used in light vector Network Analyzer, realize higher resolution ratio.
2016, Australian Song et al. proposed a kind of the unilateral of the coupled resonator optical waveguide filter based on silicon-on-insulator
Band modulator, OSSB signal after dispersion element transmits, radio frequency that photodetector measures (Radio frequency,
RF) fluctuating of signal is less than 2dB.The shortcoming of the above this method that single sideband modulated signal is realized using optical filter
Be filter use can fix lose a part of sideband energy, the energy conversion efficiency (power utilization) of signal is no
It is high.
2005, Y.Shen et al. proposed the ROF system for generating 11GHz optics single sideband modulation.Using in optical fiber
Stimulated Brillouin scattering effect is amplified the modulated signal of lower sideband, and the modulated signal of upper side band is weakened, to improve
The performance of system, obtains the snr gain of 2dB.Since Brillouin shift is 11GHz or so in optical fiber, so that modulation
Radio frequency signal frequency is 11GHz.The production method of this OSSB signal is substantially that the energy on a sideband is passed through optical fiber
Stimulated Brillouin scattering effect is transferred on another sideband, has higher effect compared with using the scheme of optical filter
Rate.
2008, Canadian B.Masella et al. proposed a kind of linear single-side belt Mach-Zehnder Electro-optical Modulation
Device, this OSSB has used the double drive Mach-Zehnder modulator for being biased in orthogonal transmission point, respectively by two phases
The RF signal for being π is moved to drive.By appropriate design, preferable modulation result is obtained.It needs to use phase-shifter in system
The phase shift of two RF driving signals is controlled, it is structurally and operationally not simple enough.
It can control the intensity ratio of each rank modulated signal in sideband using multifrequency phase modulation technique, it is special to have been used at present
The generation of line structure.Harbin Institute of Technology Lv Zhiwei teaches seminar using multifrequency phase modulation technology constant amplitude light
The generation of spectrum structure has obtained tens of constant amplitude spectrum lines by reasonably designing the ratio of each frequency content in modulated signal
Export (the patent No.: 200710144442.3).
Summary of the invention
The present invention is to solve the problems, such as that the power utilization of prior art signal is not high, device structure is more complex, is provided
A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation.
A kind of laser frequency shifter based on multifrequency phase modulation of the present invention, comprising:
The laser source of narrow linewidth, electrooptic modulator, bandpass filter, spectral measurement system, arbitrary waveform generator and
Radio frequency signal amplifiers；
The bandpass filter includes optical fiber circulator and fiber bragg grating；
The output optical fibre of the laser source of the narrow linewidth is connected with the input terminal of electrooptic modulator, the laser of the narrow linewidth
The simple signal of source output is imported into electrooptic modulator；
The input terminals of the radio frequency signal amplifiers connects arbitrary waveform generator, the output end of radio frequency signal amplifiers with
The electrooptic modulator is connected, the optical fiber circulator of the output end access bandpass filter of the electrooptic modulator, the optical fiber
Bragg grating is connect with optical fiber circulator, and the input terminal of spectral measurement system and the optical fiber circulator of bandpass filter connect；
Arbitrary waveform generator generates multifrequency modulation signal, amplifies by radio frequency signal amplifiers, is then delivered to electric light tune
Device processed；Electrooptic modulator carries out phase-modulation to the simple signal entered in electrooptic modulator according to multifrequency modulation signal, defeated
For modulated optical signal into the optical fiber circulator of bandpass filter, optical fiber circulator is passed to optical fiber Bragg light out
Grid；Fiber bragg grating filters out the highest spectrum component of intensity, exports to optical fiber circulator, optical fiber circulator is again by shift frequency
Signal afterwards is transmitted in spectral measurement system.
A kind of laser frequency shift method based on multifrequency phase modulation of the present invention, is achieved through the following technical solutions:
Step 1: the simple signal that the laser source of narrow linewidth exports is imported into electrooptic modulator；
Step 2: obtaining multifrequency modulation signal waveform based on spectrum analysis retrospectively calculate, appointed according to calculated result setting
Waveform generator of anticipating generates corresponding multifrequency modulation signal；
Step 3: the multifrequency modulation signal first passes through radio frequency signal amplifiers and amplifies, it is then delivered to electric light
Modulator；Electrooptic modulator is under the driving of the multifrequency modulation signal of process radio frequency signal amplifiers amplification to entrance electric light tune
Simple signal in device processed carries out phase-modulation, and simple signal is modulated；
Step 4: electrooptic modulator exports modulated optical signal into the optical fiber circulator of bandpass filter, fiber optic loop
Shape device is passed to fiber bragg grating；Fiber bragg grating carries out different frequency ingredient in modulated optical signal
Selective reflecting, when the center of fiber bragg grating frequency matches with the strongest spectrum component of light intensity in modulated optical signal
When, it is reflected, is filtered out the highest spectrum component of intensity to realize；Signal after the shift frequency of fiber bragg grating reflection
It is again introduced into optical fiber circulator；
Step 5: the signal after shift frequency is output to progress spectral composition analysis in spectral measurement system by optical fiber circulator.
Present invention feature the most prominent and significant beneficial effect are:
A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation of the present invention, is modulated based on multifrequency phase
Technology utilizes common mach zhender electrooptic modulator and fiber bragg grating (Fiber Bragg grating, FBG)
Realize that efficient FS signal generates, basic thought is the RF driving signal being applied on electrooptic modulator by rational design,
It shifts the power of a sideband components in optical signal to another sideband, is then selected this sideband using FBG bandpass filter
Out, finally realize that efficient FS signal generates.Laser frequency shifter structure of the present invention is simple, used an electrooptic modulator and
The output of laser frequency shift signal can be realized in one FBG filter, therefore is also convenient for operating；Also, signal power of the present invention utilizes
Rate is high, and the signal power of mono- sideband of ODSB is transferred on another sideband by multifrequency phase modulation, then uses FBG bandpass filtering
Device is selected, and up to 90% power utilization may be implemented.
Detailed description of the invention
Fig. 1 is the laser frequency shifter structural schematic diagram of the present invention based on multifrequency phase modulation；
Fig. 2 is the structural schematic diagram of bandpass filter；
Fig. 3 is the modulation signal waveform diagram in embodiment for realizing single sideband modulation；
Fig. 4 is the reflectance spectrum curve graph of optical fiber bragg grating FBG；
Fig. 5 is the power spectrum chart of signal light before and after the laser frequency displacement based on multifrequency phase modulation；
1. the laser source of narrow linewidth, 2. electrooptic modulators, 3. bandpass filters, 4. spectral measurement systems, 5. random waveforms
Generator, 6. radio frequency signal amplifiers, 3-1. optical fiber circulator, 3-2. fiber bragg grating.
Specific embodiment
Specific embodiment 1: as shown in Figure 1 and Figure 2, a kind of swashing based on multifrequency phase modulation that present embodiment provides
Optical frequency shift device, laser source 1, electrooptic modulator 2, bandpass filter 3, spectral measurement system 4, random waveform hair including narrow linewidth
Raw device 5 and radio frequency signal amplifiers 6；
The output optical fibre of the laser source 1 of the narrow linewidth is connected with the tail optical fiber of the input terminal of electrooptic modulator 2, the narrow line
The simple signal that wide laser source 1 exports is imported into electrooptic modulator 2；
The input terminal of the radio frequency signal amplifiers 6 connects arbitrary waveform generator 5, the output of radio frequency signal amplifiers 6
End is connected with the electrooptic modulator 2, the optical fiber circulator 3- of the output end access bandpass filter 3 of the electrooptic modulator 2
1, the fiber bragg grating 3-2 is connect with optical fiber circulator 3-1, the input terminal and bandpass filter 3 of spectral measurement system 4
Optical fiber circulator 3-1 connection；Arbitrary waveform generator 5 generates multifrequency modulation signal, carries out by radio frequency signal amplifiers 6
Amplification, is then delivered to electrooptic modulator 2；Electrooptic modulator 2 is according to multifrequency modulation signal in entrance electrooptic modulator 2
Simple signal carries out phase-modulation, exports modulated optical signal into the optical fiber circulator 3-1 of bandpass filter 3, fiber optic loop
Shape device 3-1 is passed to fiber bragg grating 3-2；Fiber bragg grating 3-2 filters out the highest spectrum component of intensity,
It exports to optical fiber circulator 3-1, optical fiber circulator 3-1 and the signal after shift frequency is transmitted in spectral measurement system 4 again.
In the present embodiment, arbitrary waveform generator 5 generates the modulation for the arbitrary shape being applied on electrooptic modulator 2
Electric signal, in order to guarantee the amplitude requirement for the electric signal being actually applied on electrooptic modulator 2, after arbitrary waveform generator 5
A radio frequency signal amplifiers 6 are connected to amplify electric signal.When without phase-modulation or being applied on electrooptic modulator 2
Modulation signal amplitude when being 0, only contain carrier component in the spectrum measured in spectral measurement system 4；When there is modulation telecommunications
When number being applied on electrooptic modulator 2, the simple signal that the laser source 1 of the narrow linewidth exports is modulated, originally simple signal
Single splitting of spectral lines Cheng Duogen spectrum line, with the adjustment of modulation signal, modulated spectrum in can reveal it is unilateral
Band structure carries out after spectrum component filters out through bandpass filter 3 as frequency shift signal.
Specific embodiment 2: the present embodiment is different from the first embodiment in that, the spectral measurement system 4 is
Spectroanalysis instrument, spectrum analyzer or scanning Fabry Parot interferometer.
Other steps and parameter are same as the specific embodiment one.
Specific embodiment 3: the present embodiment is different from the first and the second embodiment in that, the narrow linewidth swashs
Light source 1 is provided by narrow linewidth semiconductor laser.The wavelength of common communication band is 1550nm and 1310nm, and laser medicine is normal
It is 1064nm with the wavelength of wave band.
Other steps and parameter are the same as one or two specific embodiments.
Specific embodiment 4: being illustrated according to Fig. 1 to present embodiment, one kind that present embodiment provides is based on more
The laser frequency shift method of frequency phase-modulation, specifically includes the following steps:
Step 1: the simple signal that the laser source of narrow linewidth exports is imported into electrooptic modulator；
Step 2: obtaining multifrequency modulation signal waveform based on spectrum analysis retrospectively calculate, appointed according to calculated result setting
Waveform generator of anticipating generates corresponding multifrequency modulation signal；
Step 3: the multifrequency modulation signal first passes through radio frequency signal amplifiers and amplifies, it is then delivered to electric light
Modulator；Electrooptic modulator is under the driving of the multifrequency modulation signal of process radio frequency signal amplifiers amplification to entrance electric light tune
Simple signal in device processed carries out phase-modulation, and simple signal is modulated；
Step 4: electrooptic modulator exports modulated optical signal into the optical fiber circulator of bandpass filter, fiber optic loop
Shape device is passed to fiber bragg grating；Fiber bragg grating carries out different frequency ingredient in modulated optical signal
Selective reflecting, when the center of fiber bragg grating frequency matches with the strongest spectrum component of light intensity in modulated optical signal
When, it is reflected, is filtered out the highest spectrum component of intensity to realize；Signal after the shift frequency of fiber bragg grating reflection
It is again introduced into optical fiber circulator；As shown in Fig. 2, inputted from the optical signals end optical fiber circulator A that electrooptic modulator tail optical fiber exports,
It is output and then enter in FBG from the end B, FBG can carry out selective reflecting, reflectance spectrum such as Fig. 4 to incident light different frequency ingredient
Shown, reflectivity is maximum at centre frequency, and reflectivity gradually weakens when deviateing centre frequency.When the center FBG frequency and modulated signal
When the middle strongest spectrum component of light intensity matches, enter optical fiber circulator from the end B again after being reflected, finally from fiber annular
The output of device C-terminal.
Step 5: the signal after shift frequency is output to progress spectral composition analysis in spectral measurement system by optical fiber circulator；
By the single splitting of spectral lines Cheng Duogen spectrum line of the original simple signal of electrooptic modulator, wherein the intensity of a spectrum line is remote
Greater than the intensity of other spectral lines, spectrum shows unilateral band structure, is frequency shift signal after bandpass filtering.
Specific embodiment 5: present embodiment be calculated unlike specific embodiment four, in step 2 it is more
The process of frequency modulation electric signal waveform includes:
Step 2 one, multifrequency modulation signal m (t) fundamental frequency be fm, making Fourier expansion then to m (t) has:
γ in formula (1)kAnd φkThe modulation index and initial phase of k subharmonic respectively in multifrequency modulation signal, when t is indicated
Between；
Step 2 two sets multifrequency modulation signal waveform γk=0, φk=0, multifrequency modulation signal waveform, that is, k subharmonic
Modulation index γkWith initial phase φkValued combinations；
Step 2 three, under the effect of this modulation signal, ignore the DC component in multifrequency modulation signal, i.e. direct current point
Measure γ0=0, simple signal is by modulated time-domain expression are as follows:
Wherein, fcFor the frequency for the simple signal that the laser source of narrow linewidth exports, j is imaginary unit；E (t) refers to adjusting
The amplitude of optical signal after system；
It is obtained on the right of formula (2) as Fourier expansion:
Wherein, n1、n2、nkFor the integer of (- ∞, ∞),For Bessel function；It is modulated through multifrequency phase
Optical signal is that a series of frequency intervals are fmDiscrete spectrum line；Signal after this single sideband modulation is imported into bandpass filtering
In device, when filter working frequency and single sideband modulated signal basic frequency match, which can be selected.Pass through adjusting
The fundamental frequency f of multifrequency modulation signal m (t)mThe size of i.e. adjustable frequency shift amount.
The spectrum structure of optical signal after the modulation for meeting formula (2) and formula (3) can be calculated by mathematical simulation software；
Step 2 four enables γk=0.01；It is calculated by formula (3) and works as φkWhen traversing all values at interval 0.01 in [- π, π]
Modulated signal spectrum, find out single order lower side frequency (using this frequency content in present embodiment, can also using other frequencies at
Point) maximum intensity a and corresponding φkValue；
Step 2 five enables γk=γk+ 0.01, the maximum of single order lower side frequency is found out according to method identical with step 2 four
Intensity b and corresponding φkValue；
Step 2 six, the size for comparing a and b, if a >=b, with the modulation index γ in step 2 fivekWith initial phase φk
Corresponding multifrequency modulation signal waveform as a result, a is strongest single order lower side frequency at this time, other frequency contents it is inevitable compared with
It is weak, the structure of single sideband modulation is presented；If a <b, b value is assigned to a, and return step two or five, until obtaining meeting condition
Multifrequency modulation signal waveform (until obtain strongest single order lower side frequency).
Above-mentioned steps increase γ by unique stepkValue, choose obtain a multifrequency modulation signal waveform, modulation after produce
Raw optical signal can satisfy required precision range.
Other steps and parameter are identical as specific embodiment four.
Specific embodiment 6: present embodiment is unlike specific embodiment four, multifrequency modulation signal fundamental frequency
Value be 1kHz~40GHz.
Other steps and parameter are identical as specific embodiment four or five.
Specific embodiment 7: present embodiment is unlike specific embodiment six, multifrequency modulation signal fundamental frequency
Value be 10.8GHz.
Other steps and parameter are identical as specific embodiment four, five or six.
Specific embodiment 8: present embodiment is applied to electric light unlike specific embodiment four in step 3
Multifrequency modulation signal on modulator includes fm、2fm、...、kfm, k frequency, k ∈ [2,10], the phase of each frequency component
φkIt is 0.
Other steps and parameter and specific embodiment four, five, six or seven are identical.
Embodiment
Beneficial effects of the present invention are verified using following embodiment:
Laser frequency shift method based on multifrequency phase modulation described in the present embodiment follows the steps below:
As shown in Figure 1, first by the tail optical fiber phase of the output optical fibre of the laser source of narrow linewidth 1 and the input terminal of electrooptic modulator 2
Even, the simple signal that the laser source 1 of the narrow linewidth exports is imported into electrooptic modulator 2；Radio frequency signal amplifiers 6 it is defeated
Enter end connection arbitrary waveform generator 5, the output end of radio frequency signal amplifiers 6 is connected with the electrooptic modulator 2, the electric light
The output end of modulator 2 accesses bandpass filter 3, and the input terminal of spectral measurement system 4 is connect with bandpass filter 3；This implementation
Spectral measurement system 3 in example uses spectroanalysis instrument；
The laser light source of narrow linewidth is provided by wavelength for the narrow linewidth semiconductor laser of 1550nm, as shown in figure 3, setting
Arbitrary waveform generator generates multifrequency modulation signal are as follows: includes fm、2fm、3fm、4fm、5fm、6fm、7fm、8fm、9fm、10fmDeng
Multifrequency modulation signal including 10 frequencies, the fundamental frequency f of multifrequency modulation signalmValue be 10.8GHz, be calculated full
The multifrequency modulation signal waveform γ required enough1=1.9900, γ2=0.9800, γ3=0.6400, γ4=0.4700, γ5=
0.3600、γ6=0.2900, γ7=0.2300, γ8=0.2700, γ9=0.2800, γ10=0.2400, each frequency component
PhasekIt is 0.
When multifrequency modulation signal amplitude be 0 do not apply modulated signal when, the line structure that measures in spectroanalysis instrument
As shown in phantom in Figure 5, only carrier component exists.If the multifrequency modulation signal waveform being calculated is added to Electro-optical Modulation
On device 2, modulated spectrum shown in solid in Fig. 5 can be obtained, it can be seen that laser frequency is from the frequency location of incoming signal to low
Frequency direction moves 20Hz, and frequency-shift signaling is declined from intensity with respect to incoming signal, and capacity usage ratio has reached 90%, in fact
The output of efficient laser frequency shift signal is showed, frequency shift amount can be by changing modulated signal fundamental frequency fmTo adjust.
The present invention can also have other various embodiments, without deviating from the spirit and substance of the present invention, this field
Technical staff makes various corresponding changes and modifications in accordance with the present invention, but these corresponding changes and modifications all should belong to
The protection scope of the appended claims of the present invention.
Claims (8)
1. a kind of laser frequency shifter based on multifrequency phase modulation, which is characterized in that the laser based on multifrequency phase modulation
Frequency shifter include the laser source of narrow linewidth, electrooptic modulator, bandpass filter, spectral measurement system, arbitrary waveform generator with
And radio frequency signal amplifiers；
The bandpass filter includes optical fiber circulator and fiber bragg grating；
The output optical fibre of the laser source of the narrow linewidth is connected with the input terminal of electrooptic modulator, and the laser source of the narrow linewidth is defeated
Simple signal out is imported into electrooptic modulator；
The input terminals of the radio frequency signal amplifiers connects arbitrary waveform generator, the output end of radio frequency signal amplifiers with it is described
Electrooptic modulator is connected, the optical fiber circulator of the output end access bandpass filter of the electrooptic modulator, the optical fiber Bradley
Lattice grating is connect with optical fiber circulator, and the input terminal of spectral measurement system and the optical fiber circulator of bandpass filter connect；Arbitrarily
Waveform generator generates multifrequency modulation signal, amplifies by radio frequency signal amplifiers, is then delivered to electrooptic modulator；
Electrooptic modulator carries out phase-modulation, output modulation to the simple signal entered in electrooptic modulator according to multifrequency modulation signal
For optical signal afterwards into the optical fiber circulator of bandpass filter, optical fiber circulator is passed to fiber bragg grating；Optical fiber
Bragg grating filters out the highest spectrum component of intensity, exports to optical fiber circulator, optical fiber circulator is again by the letter after shift frequency
It number is transmitted in spectral measurement system.
2. a kind of laser frequency shifter based on multifrequency phase modulation according to claim 1, it is characterised in that: the spectrum is surveyed
Amount system is spectroanalysis instrument, spectrum analyzer or scanning Fabry Parot interferometer.
3. a kind of laser frequency shifter based on multifrequency phase modulation according to claim 1 or claim 2, it is characterised in that: described narrow
The laser source of line width is provided by narrow linewidth semiconductor laser.
4. a kind of frequency shift method using the laser frequency shifter based on multifrequency phase modulation described in claims 1 to 33, feature exist
In, the method specifically includes the following steps:
Step 1: the simple signal that the laser source of narrow linewidth exports is imported into electrooptic modulator；
Step 2: obtaining multifrequency modulation signal waveform based on spectrum analysis retrospectively calculate, any wave is set according to calculated result
Shape generator generates corresponding multifrequency modulation signal；
Step 3: the multifrequency modulation signal first passes through radio frequency signal amplifiers and amplifies, it is then delivered to Electro-optical Modulation
Device；Electrooptic modulator by radio frequency signal amplifiers amplification multifrequency modulation signal driving under to enter electrooptic modulator
In simple signal carry out phase-modulation, simple signal modulated；
Step 4: electrooptic modulator exports modulated optical signal into the optical fiber circulator of bandpass filter, optical fiber circulator
It is passed to fiber bragg grating；Fiber bragg grating selects different frequency ingredient in modulated optical signal
Sexual reflex, when fiber bragg grating center frequency with the strongest spectrum component of light intensity matches in modulated optical signal when,
It is reflected, is filtered out the highest spectrum component of intensity to realize；Signal after the shift frequency of fiber bragg grating reflection is again
It is secondary to enter optical fiber circulator；
Step 5: the signal after shift frequency is output to progress spectral composition analysis in spectral measurement system by optical fiber circulator.
5. a kind of laser frequency shift method based on multifrequency phase modulation according to claim 4, which is characterized in that in step 2
The process that multifrequency modulation signal waveform is calculated includes:
Step 2 one, multifrequency modulation signal m (t) fundamental frequency be fm, making Fourier expansion then to m (t) has:
γ in formula (1)kAnd φkThe modulation index and initial phase of k subharmonic respectively in multifrequency modulation signal, t indicate the time；
Step 2 two sets multifrequency modulation signal waveform γk=0, φk=0, multifrequency modulation signal waveform, that is, k subharmonic tune
Exponent gamma processedkWith initial phase φkValued combinations；
Step 2 three ignores DC component in multifrequency modulation signal, i.e. DC component γ0=0, after simple signal is modulated
Time-domain expression are as follows:
Wherein, fcFor the frequency for the simple signal that the laser source of narrow linewidth exports, j is imaginary unit；E (t) refers to light after modulation
The amplitude of signal；
It is obtained on the right of formula (2) as Fourier expansion:
Wherein, n1、n2、nkFor the integer of (- ∞, ∞),For Bessel function；Through the modulated light letter of multifrequency phase
Number for a series of frequency intervals be fmDiscrete spectrum line；
The spectrum structure of optical signal after meeting the modulation of formula (2) and formula (3) is calculated by mathematical simulation software；
Step 2 four enables γk=0.01；It is calculated by formula (3) and works as φkTraverse the tune when all values at interval 0.01 in [- π, π]
Signal spectrum processed finds out the maximum intensity a and corresponding φ of single order lower side frequencykValue；
Step 2 five enables γk=γk+ 0.01, the maximum intensity b of single order lower side frequency is found out according to method identical with step 2 four
And corresponding φkValue；
Step 2 six, the size for comparing a and b, if a >=b, with the modulation index γ in step 2 fivekWith initial phase φkInstitute is right
The multifrequency modulation signal waveform answered is as a result；If a <b, b value is assigned to a, and return step two or five.
6. a kind of laser frequency shift method based on multifrequency phase modulation according to claim 4, it is characterised in that: multifrequency modulation
The value of electric signal fundamental frequency is 1kHz~40GHz.
7. a kind of laser frequency shift method based on multifrequency phase modulation according to claim 6, it is characterised in that: multifrequency modulation
The value of electric signal fundamental frequency is 10.8GHz.
8. a kind of laser frequency shift method based on multifrequency phase modulation according to claim 4, it is characterised in that: in step 3
The multifrequency modulation signal being applied on electrooptic modulator includes fm、2fm、...、kfm, k frequency, k ∈ [2,10], each frequency
The phase of componentkIt is 0.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811133993.4A CN109067469A (en) | 2018-09-27 | 2018-09-27 | A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811133993.4A CN109067469A (en) | 2018-09-27 | 2018-09-27 | A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109067469A true CN109067469A (en) | 2018-12-21 |
Family
ID=64766260
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811133993.4A Pending CN109067469A (en) | 2018-09-27 | 2018-09-27 | A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109067469A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110429978A (en) * | 2019-07-15 | 2019-11-08 | 上海交通大学 | Optical fiber microwave frequency transmission system for optical fibre ring link |
| CN111447661A (en) * | 2020-01-21 | 2020-07-24 | 中国人民解放军陆军工程大学 | Optical terminal equipment and working method thereof |
| CN112415789A (en) * | 2020-08-13 | 2021-02-26 | 中国人民解放军国防科技大学 | All-fiber coupling single-frequency light output GHz-level frequency shift method and system |
| US20210075191A1 (en) * | 2019-09-10 | 2021-03-11 | Toptica Projects Gmbh | Laser system for Generating Single-Sideband Modulated Laser Radiation |
| CN113507274A (en) * | 2021-07-05 | 2021-10-15 | 山东大学 | Method and device for realizing continuous adjustment of micro-resonator sideband by injection locking |
| CN116742465A (en) * | 2023-08-14 | 2023-09-12 | 中国科学院长春光学精密机械与物理研究所 | Method and chip for generating linear frequency modulation laser |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101141200A (en) * | 2007-10-15 | 2008-03-12 | 哈尔滨工业大学 | Multi-frequency phase modulation based multi-wavelength source generating method and apparatus |
| CN105651492A (en) * | 2016-02-29 | 2016-06-08 | 武汉理工大学 | Laser line width measuring system and method based on electro-optic modulator and adjustable radio source |
| CN105763266A (en) * | 2016-05-04 | 2016-07-13 | 北京邮电大学 | Method for simultaneously achieving down conversion and phase shifting of microwave photons |
| CN107947867A (en) * | 2017-12-05 | 2018-04-20 | 安徽工程大学 | A kind of single-side belt frequency spectrum generation device and method based on multifrequency phase modulation |
-
2018
- 2018-09-27 CN CN201811133993.4A patent/CN109067469A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101141200A (en) * | 2007-10-15 | 2008-03-12 | 哈尔滨工业大学 | Multi-frequency phase modulation based multi-wavelength source generating method and apparatus |
| CN105651492A (en) * | 2016-02-29 | 2016-06-08 | 武汉理工大学 | Laser line width measuring system and method based on electro-optic modulator and adjustable radio source |
| CN105763266A (en) * | 2016-05-04 | 2016-07-13 | 北京邮电大学 | Method for simultaneously achieving down conversion and phase shifting of microwave photons |
| CN107947867A (en) * | 2017-12-05 | 2018-04-20 | 安徽工程大学 | A kind of single-side belt frequency spectrum generation device and method based on multifrequency phase modulation |
Non-Patent Citations (1)
| Title |
|---|
| J. CAPMANY等: ""Multiwavelength single sideband modulation for WDM radio-over-fiber systems using a fiber grating array tandem device"", 《IEEE PHOTONICS TECHNOLOGY LETTERS》 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110429978A (en) * | 2019-07-15 | 2019-11-08 | 上海交通大学 | Optical fiber microwave frequency transmission system for optical fibre ring link |
| CN110429978B (en) * | 2019-07-15 | 2022-05-17 | 上海交通大学 | Optical fiber microwave frequency transmission system for ring optical fiber link |
| US20210075191A1 (en) * | 2019-09-10 | 2021-03-11 | Toptica Projects Gmbh | Laser system for Generating Single-Sideband Modulated Laser Radiation |
| CN111447661A (en) * | 2020-01-21 | 2020-07-24 | 中国人民解放军陆军工程大学 | Optical terminal equipment and working method thereof |
| CN111447661B (en) * | 2020-01-21 | 2023-06-20 | 中国人民解放军陆军工程大学 | Optical terminal equipment and working method thereof |
| CN112415789A (en) * | 2020-08-13 | 2021-02-26 | 中国人民解放军国防科技大学 | All-fiber coupling single-frequency light output GHz-level frequency shift method and system |
| CN113507274A (en) * | 2021-07-05 | 2021-10-15 | 山东大学 | Method and device for realizing continuous adjustment of micro-resonator sideband by injection locking |
| CN113507274B (en) * | 2021-07-05 | 2023-10-31 | 山东大学 | Method and device for realizing continuous adjustment of sidebands of micro resonator by using injection locking |
| CN116742465A (en) * | 2023-08-14 | 2023-09-12 | 中国科学院长春光学精密机械与物理研究所 | Method and chip for generating linear frequency modulation laser |
| CN116742465B (en) * | 2023-08-14 | 2023-11-14 | 中国科学院长春光学精密机械与物理研究所 | Method and chip for generating linear frequency modulation laser |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109067469A (en) | A kind of laser frequency shifter and frequency shift method based on multifrequency phase modulation | |
| CN103166706B (en) | Based on the photoelectric oscillation device of the frequency-tunable of wide spectrum light source | |
| CN103091932B (en) | Single-band-pass microwave photon filter with super-wide tuning range | |
| CN103278941B (en) | Based on microwave photon filter and the filtering method thereof of stimulated Brillouin scattering dynamic raster | |
| CN103018928B (en) | Tunable microwave photonic filter based on photoinjection semiconductor laser system | |
| CN103346469B (en) | A kind of optical-electronic oscillator | |
| CN101436905A (en) | Tunable microwave photon filter based on Brillouin optical fiber laser | |
| CN104330939A (en) | SBS broadband tunable optical fiber delay system | |
| CN101951294B (en) | Microwave/millimeter wave signal generating device with continuously tunable broadband | |
| CN105141258A (en) | Microwave frequency conversion method and apparatus | |
| CN107947867B (en) | Single-sideband spectrum generation device and method based on multi-frequency phase modulation | |
| CN103513491B (en) | A kind of method and apparatus producing optical frequency com based on Parabolic Phase modulation | |
| CN109301686A (en) | A kind of the femto-second laser pulse generation system and method for high repetition frequency | |
| CN113224622A (en) | Communication band high-flatness large-comb-tooth-spacing linear polarization electro-optic modulation optical frequency comb light source | |
| CN204190774U (en) | A kind of optical triangulation shape pulse generator based on four times of rf modulations | |
| CN105187131A (en) | Wavelength-tunable coherent light detection system and method based on supercontinuum | |
| CN101834670A (en) | High linear response microwave photon signal modulation and demodulation device | |
| CN102594544A (en) | Spectral broadening device for chaotic laser signals and method thereof | |
| Li et al. | Photonic generation of microwave binary digital modulation signal with format agility and parameter tunability | |
| CN201234258Y (en) | Dual path microwave/millimeter wave generator for Sagnac optical fiber loop | |
| CN114336227B (en) | Microwave signal generating device based on low-distortion dissipative Kerr soliton | |
| CN217060716U (en) | Optical frequency comb generation device for phase modulation and stimulated Brillouin scattering | |
| Wang et al. | Full-duplex radio-over-fiber system with tunable millimeter-wave signal generation and wavelength reuse for upstream signal | |
| Gu et al. | Polarization dependence of stimulated Brillouin scattering-based switchable microwave photonic filter | |
| Guan et al. | Optical frequency comb with tunable free spectral range based on two Mach-Zehnder modulators cascaded with linearly chirped fiber Bragg grating and phase modulator |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20181221 |