CN106656322A - Device and method for realizing instantaneous frequency measurement using phase modulator - Google Patents
Device and method for realizing instantaneous frequency measurement using phase modulator Download PDFInfo
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- CN106656322A CN106656322A CN201610846182.3A CN201610846182A CN106656322A CN 106656322 A CN106656322 A CN 106656322A CN 201610846182 A CN201610846182 A CN 201610846182A CN 106656322 A CN106656322 A CN 106656322A
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- 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
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0795—Performance monitoring; Measurement of transmission parameters
- H04B10/07955—Monitoring or measuring power
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Abstract
The invention discloses a device and a method for realizing instantaneous frequency measurement using a lithium niobate phase modulator. The device and the method relate to the technical field of microwave and the technical field of optical communication, and are mainly applied to the field of electronic reconnaissance. The device comprises a laser, a polarization controller, a phase modulator, a standard single-mode optical fiber, an optical divider, a polarizer and an optical receiver, as shown in the appended drawings. By using the polarization sensitive property of the lithium niobate phase modulator and reasonably adjusting the polarization controller, phase modulation and intensity modulation can be realized at the same time. Based on the dispersion characteristic of the optical fiber, two frequency response functions opposite in change trend can be constructed. Thus, an amplitude comparison function obtained changes more quickly in a large band. By calculating the power ratio of upper and lower branches, the frequency of a to-be-measured microwave signal can be estimated. The measurement error of the device within the range from 1.6GHz to 24.6GHz is less than +/-0.3GHz.
Description
Technical field
The present invention relates to technical field of photo communication and microwave technical field, more particularly to it is a kind of based on the micro- of phase-modulator
Ripple signal transient frequency measuring equipment.
Background technology
It is to realize intercepting and capturing and recognizing coming from the radar of enemy or the radiation information of communication system in electronic warfare field,
Firstly the need of the operating frequency for estimating its electronic system.Can rapidly realize estimating to radiating source frequency by instantaneous frequency measurement technology
Meter, in order to realize electronic reconnaissance, attack and defense.
Traditional electrical domain instantaneous frequency measurement system is typically realized to Frequency Estimation by microwave interference.Using microwave interference technology
Instantaneous Frequency Measurement system need to use RF Power Splitter and radio-frequency transmission line, and which has limited the expansion of system operating frequency
Exhibition.As modern radar system gradually extends to higher frequency section, electrical domain Frequency Measurement System will no longer be suitable for.
Microwave photon technology can solve conventional electronics method and be difficult even insurmountable problem.Using microwave photon
The Instantaneous Frequency Measurement system of technology auxiliary, can be operated in higher frequency section, dry with more low-loss, smaller szie and anti-electromagnetism
The advantages of disturbing.Therefore, it is expected to play important in future electronic war field based on the Technology of Measuring Instant Frequency of microwave photon technology
Effect.
The present invention proposes a kind of microwave photon auxiliary Instantaneous Frequency Measurement system of simple structure.Using lithium niobate phase
The modulator characteristic inconsistent to TE and TM optical mode modulation efficiencies, is divided into upper and lower two branch roads, using list by modulated optical signal
The dispersion characteristics of mode fiber, can construct two contrary power fading functions of variation tendency in upper and lower two branch road respectively.It is logical
The power ratio for comparing two paths of signals is crossed, the frequency values of incident microwave signals can be quickly estimated.The apparatus structure is simple,
Only need a light source and a phase-modulator, it is easy to accomplish.
The content of the invention
The present invention technical solution be：The device of Instantaneous Frequency Measurement is realized using phase-modulator, its feature exists
In：Described device include distributed feedback laser, Polarization Controller, phase-modulator, standard single-mode fiber, optical branching device, rise
Inclined device and photodetector, vector network analyzer.The output end of laser instrument is through the first Polarization Controller and phase-modulation
Device is connected, and the output end of phase-modulation is connected with standard single-mode fiber, and optical fiber output port is connected with optical branching device, optical branching device
The first output port be connected with photoreceiver 1, the second output port of optical branching device be sequentially connected respectively Polarization Controller and
The polarizer, finally injects photoreceiver 2.
Above-mentioned phase-modulator is Z axis cutting phase modulator, to the modulation efficiency of TM optical modes apparently higher than TE optical modes
Formula.
Above-mentioned photoreceiver is made up of an integrated PIN diode of waveguide and a trans-impedance amplifier.
Realize that the method that transient microwave frequency is measured is comprised the following steps using phase-modulator：
(1) wavelength exported by laser instrument is injected in phase-modulator for the linearly polarized light of λ through Polarization Controller, adjusts inclined
Controller shake so that incident ray polarized light is in 45 ° with the main shaft of phase-modulator；
(2) prevention at radio-frequency port of the phase modulated device of microwave signal to be measured of unknown frequency is loaded on phase-modulator, is modulated defeated
Go out the polarisation-multiplexed signal of TM and TE；
(3) polarisation-multiplexed signal is transmitted through 5km standard single-mode fibers；
(4) the palarization multiplexing optical signal of Jing Optical Fiber Transmissions is divided into into upper and lower two branch roads using optical branching device；
(5) optical signal of branch road is directly injected into photoreceiver on；
(6) optical signal of branch road first passes through Polarization Controller under, and the interference of TE and TM polarization signals is then realized at the polarizer,
Light wave after interference is linearly polarized light, into photoreceiver.
(7) by the Polarization Controller of the lower branch road of regulation, the main shaft of the polarizer and the angle of TE and TM polarization states can simultaneously be changed,
And the relative phase shift between two polarization states of TE and TM, the frequency response function for realizing upper and lower two branch road has contrary change
Trend.
(8) by the electric signal power ratio of upper and lower two branch road of calculating, the frequency values of microwave signal to be measured can uniquely be determined.
The present invention proposes a kind of microwave photon auxiliary Instantaneous Frequency Measurement device of simple structure.The device utilizes niobic acid
The lithium phase-modulator characteristic different to the modulation efficiency of TE with TM optical modes, by modulated optical signal upper and lower two branch roads are divided into,
Using the dispersion characteristics of single-mode fiber, respectively two contrary frequency response letters of variation tendency can be constructed in upper and lower two branch road
Number, by the power of relatively more upper and lower branch road, can construct an amplitude comparison function with larger slope, and then realize bigger
High accuracy Instantaneous Frequency Measurement in bandwidth range.
The method only needs a phase-modulator, therefore does not need bias control circuit.The configuration of single lasing light emitter is caused
System does not need OWDM device, and frequency-measurement accuracy not to be floated by light source power and affected.
The method does not need the device of the frequency limited such as RF Power Splitter or electric frequency mixer, the frequency measurement scope only light of system
The bandwidth of emitter and photoreceiver is limited.
Description of the drawings
Fig. 1 is Instantaneous Frequency Measurement schematic diagram of the present invention based on phase-modulator；
Fig. 2 is the frequency response function figure of upper and lower two branch road in experiment test；
Fig. 3 is the two branch power ratio curve figure up and down for obtaining in experiment test；
Fig. 4 is frequency measurement in experiment test；
Fig. 5 is frequency error measurement result figure in experiment test.
Specific embodiment
Embodiments of the invention are elaborated below in conjunction with the accompanying drawings：The present embodiment is with technical solution of the present invention as front
Put and implemented, give detailed embodiment and specific operating process, but protection scope of the present invention is not limited to down
The embodiment stated：
As shown in figure 1, in the present embodiment, device includes：Distributed feedback laser, Polarization Controller 1, vector network analyzer,
Phase-modulator, optical branching device, the Polarization Controller 2, polarizer, photoreceiver 1 and photoreceiver 2.The output port of laser instrument
It is connected with the input port of Polarization Controller 1, the output of Polarization Controller is connected with the input port of phase-modulator, radio frequency letter
Number output in source is connected with the prevention at radio-frequency port of phase-modulator.The input port phase of the output port of phase-modulator and optical fiber
Even, the output port of optical fiber is connected with the input port of optical branching device, the upper branch road of optical branching device export directly with photoreceiver 1
It is connected, the lower branch road output of optical branching device is sequentially connected respectively Polarization Controller 2 and the polarizer, the output port and light of the polarizer
The input port of receiver is connected.By adjusting two Polarization Controllers, the frequency response function of upper and lower two branch road possesses on the contrary
Variation tendency, by calculate power ratio can estimate radiofrequency signal input power.
In this example, the specific implementation step of method is：
Step one, laser instrument generation operation wavelength λ are input to half-wave voltage and are for the light carrier of 1552nm Jing after Polarization Controller 1
The Z axis cutting phase modulator of 7V.Adjustment Polarization Controller 1 is so that the linearly polarized light of input is in the main shaft of phase-modulator
45°.Vector network analyzer radio frequency output be connected with the prevention at radio-frequency port of phase-modulator, export radio-frequency power be set to-
3dBm。
Polarisation-multiplexed signal after step 2, modulation is input in 5km standard single-mode fibers, and the abbe number of optical fiber is 17ps/
nm/km。
Step 3, the optical signal of optical fiber output are divided into upper and lower two branch roads.Upper branch road is directly connected with photoreceiver 1, lower branch road
Output is connected successively with the Polarization Controller 2, polarizer and photoreceiver 2.Adjust Polarization Controller 2 cause two polarization states it
Between the relative phase shift that introduces be 0.8 π, polarization direction and polarizer angle are 0.14 π.
Step 4, the output end of photoreceiver are connected with the rf inputs of vector network analyzer.Using vector network analysis
Instrument can obtain the frequency response curve of upper and lower two branch road, as shown in Figure 2.
Step 5, according to the frequency response curve of gained, using the power ratio of upper and lower two branch road can construct Amplitude Ratio compared with
Function, as shown in Figure 3.Using measured data frequency is set up with radio-frequency power than corresponding look-up table.
Step 6, for the feasibility of validated measurement systems, the RF signal power of input is changed to into -20dBm, change input letter
Number frequency, and record the power of upper and lower two branch road.Using the look-up table set up, estimating for frequency is realized in the search by tabling look-up
Meter.Measurement result is as shown in figure 4, corresponding measure error is as shown in figure 5, error is less than ± 0.3GHz.
To sum up, the present invention realizes the Instantaneous Frequency Measurement to microwave signal using lithium niobate phase modulator, the device
Simple structure is easily achieved, cheap, is not affected by electronic bottleneck.Further, since use only single lasing light emitter, system is not
WDM device, and certainty of measurement is needed not to be affected by light source power fluctuation.The program only needs a phase-modulator,
Not there are problems that the bias drift produced by ambient influnence, therefore do not need complicated bias control circuit.By constructing two
The contrary frequency response function of variation tendency, the program is capable of achieving the microwave frequency measurement of large scale and high accuracy.
In a word, embodiments described above is only embodiments of the invention, is not only used for limiting the protection model of the present invention
Enclose, it is noted that for those skilled in the art, in present disclosure, can also make
Some equivalent variations and replacement, phase-modulator is not limited to Z axis cutting, optical carrier wavelength, the length of optical fiber, dispersion values, polarization
The adjustment of state etc. also should be regarded as the scope of protection of the invention.
Claims (4)
1. a kind of utilization phase-modulator realizes the device and method of Instantaneous Frequency Measurement, it is characterised in that：Described device includes
Distributed feedback laser, Polarization Controller, phase-modulator, standard single-mode fiber, optical branching device, the polarizer and light-receiving
Machine.The output of laser instrument is connected through the first Polarization Controller with phase-modulator, the microwave signal to be measured input of unknown frequency
The prevention at radio-frequency port of phase-modulator, the output of phase-modulator is connected with optical fiber, and optical fiber output port is connected with optical branching device, light
First output port of shunt is connected with photoreceiver, and the second output port of optical branching device is sequentially connected respectively Polarization Control
Device and the polarizer, finally inject photoreceiver.Can estimate the frequency of measured signal by measuring and comparing the radio-frequency power of output
Rate information.
The phase-modulator is different for the modulation efficiency of TE with TM optical modes, by adjust the first Polarization Controller cause into
Ray polarised light is with phase-modulator main shaft at an angle.After Optical Fiber Transmission, the upper branch road of optical branching device is output as phase
Position modulated signal, adjusts the second Polarization Controller of lower branch road, can realize that electro-optic intensity is modulated after the polarizer.Consider
The frequency response function of effect of dispersion, upper branch road and lower branch road has contrary variation tendency.
The frequency response function of upper and lower two branch road can be measured using vector network analyzer, using the data obtained, is propped up in calculating
Road can set up the look-up table of frequency-radio-frequency power ratio with the power ratio of lower branch road.
For the microwave signal to be measured of unknown frequency, the power ratio of upper and lower branch road is calculated, can be with by searching for the method for look-up table
The quick frequency information for estimating measured signal.
2. utilization phase-modulator according to claim 1 realizes the device of Instantaneous Frequency Measurement, it is characterised in that：Phase place
Modulator is different for the modulation efficiency of TE with TM optical modes, can simultaneously realize that phase place is adjusted with reference to Polarization Controller and the polarizer
System and intensity modulated.
3. utilization phase-modulator according to claim 1 realizes the device of Instantaneous Frequency Measurement, and device is characterised by：Monochromatic light
Source use so that Frequency Measurement System not by light source power fluctuation affected.Due to adopting phase-modulator, the device need not be answered
Miscellaneous bias control circuit.The system does not need the frequency limited device such as RF Power Splitter and frequency mixer, frequency measurement scope only to receive phase
The bandwidth of position modulator and light-receiving is limited.
4. utilization phase-modulator according to claim 1 realizes the device of Instantaneous Frequency Measurement, it is characterised in that：Up and down
The frequency response function of branch road has contrary variation tendency, by the power ratio for calculating upper and lower two branch road, the Amplitude Ratio of gained
There is larger slope in bigger frequency range compared with function.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107835053A (en) * | 2017-11-08 | 2018-03-23 | 西安电子科技大学 | A kind of high-precision transient microwave frequency measurement apparatus |
| CN108226297A (en) * | 2018-01-15 | 2018-06-29 | 国网江苏省电力公司检修分公司特高压交直流运检中心 | A kind of vacuum tube bellows surface crack detecting method based on fiber grating |
| CN108449131A (en) * | 2018-04-16 | 2018-08-24 | 苏州六幺四信息科技有限责任公司 | A kind of coherent optical heterodyne communicatio measurement method of parameters, device based on mixing |
| CN108833006A (en) * | 2018-06-29 | 2018-11-16 | 中国科学院半导体研究所 | Instantaneous Frequency Measurement device and method based on microwave photon filter |
| CN109951227A (en) * | 2019-02-12 | 2019-06-28 | 中国科学院半导体研究所 | Microwave instantaneous frequency measurement device, circuit and method |
| CN110059326A (en) * | 2018-04-20 | 2019-07-26 | 南方科技大学 | It is a kind of for debugging the emulation mode and analogue system of microwave device |
| CN110632388A (en) * | 2019-09-27 | 2019-12-31 | 南京航空航天大学 | Frequency mixing-based photoelectric detector frequency response measuring method and device |
| CN110988474A (en) * | 2019-12-26 | 2020-04-10 | 中国科学院国家天文台 | Spectrum measuring system |
| CN111277325A (en) * | 2020-01-20 | 2020-06-12 | 北京邮电大学 | Instantaneous frequency measurement method and system with adjustable measurement range based on polarization modulator |
| CN112751610A (en) * | 2020-12-29 | 2021-05-04 | 武汉光迅科技股份有限公司 | Method and system for measuring SMZM modulation arm phase shift function |
| CN115225159A (en) * | 2022-07-15 | 2022-10-21 | 中国电子科技集团公司第三十四研究所 | Device and method for enhancing demodulation optical signal-to-noise ratio of optical phase modulation signal |
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| CN107835053A (en) * | 2017-11-08 | 2018-03-23 | 西安电子科技大学 | A kind of high-precision transient microwave frequency measurement apparatus |
| CN107835053B (en) * | 2017-11-08 | 2020-10-20 | 西安电子科技大学 | High-precision instantaneous microwave frequency measuring device |
| CN108226297A (en) * | 2018-01-15 | 2018-06-29 | 国网江苏省电力公司检修分公司特高压交直流运检中心 | A kind of vacuum tube bellows surface crack detecting method based on fiber grating |
| CN108449131A (en) * | 2018-04-16 | 2018-08-24 | 苏州六幺四信息科技有限责任公司 | A kind of coherent optical heterodyne communicatio measurement method of parameters, device based on mixing |
| CN110059326A (en) * | 2018-04-20 | 2019-07-26 | 南方科技大学 | It is a kind of for debugging the emulation mode and analogue system of microwave device |
| CN110059326B (en) * | 2018-04-20 | 2023-05-05 | 南方科技大学 | Simulation method and simulation system for debugging microwave device |
| CN108833006A (en) * | 2018-06-29 | 2018-11-16 | 中国科学院半导体研究所 | Instantaneous Frequency Measurement device and method based on microwave photon filter |
| CN109951227A (en) * | 2019-02-12 | 2019-06-28 | 中国科学院半导体研究所 | Microwave instantaneous frequency measurement device, circuit and method |
| CN110632388A (en) * | 2019-09-27 | 2019-12-31 | 南京航空航天大学 | Frequency mixing-based photoelectric detector frequency response measuring method and device |
| CN110632388B (en) * | 2019-09-27 | 2020-10-02 | 南京航空航天大学 | Frequency mixing-based photoelectric detector frequency response measuring method and device |
| CN110988474B (en) * | 2019-12-26 | 2021-09-28 | 中国科学院国家天文台 | Spectrum measuring system |
| CN110988474A (en) * | 2019-12-26 | 2020-04-10 | 中国科学院国家天文台 | Spectrum measuring system |
| CN111277325A (en) * | 2020-01-20 | 2020-06-12 | 北京邮电大学 | Instantaneous frequency measurement method and system with adjustable measurement range based on polarization modulator |
| CN111277325B (en) * | 2020-01-20 | 2021-05-04 | 北京邮电大学 | Instantaneous frequency measurement method and system with adjustable measurement range based on polarization modulator |
| CN112751610A (en) * | 2020-12-29 | 2021-05-04 | 武汉光迅科技股份有限公司 | Method and system for measuring SMZM modulation arm phase shift function |
| CN115225159A (en) * | 2022-07-15 | 2022-10-21 | 中国电子科技集团公司第三十四研究所 | Device and method for enhancing demodulation optical signal-to-noise ratio of optical phase modulation signal |
| CN115225159B (en) * | 2022-07-15 | 2023-10-13 | 中国电子科技集团公司第三十四研究所 | Device and method for enhancing demodulation signal-to-noise ratio of high-light phase modulation signal |
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