CN105242274B - ionosphere incoherent scattering radar differential phase detection method - Google Patents
ionosphere incoherent scattering radar differential phase detection method Download PDFInfo
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- CN105242274B CN105242274B CN201510700313.2A CN201510700313A CN105242274B CN 105242274 B CN105242274 B CN 105242274B CN 201510700313 A CN201510700313 A CN 201510700313A CN 105242274 B CN105242274 B CN 105242274B
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Abstract
The invention provides a kind of ionosphere incoherent scattering radar differential phase detection method, step is as follows：1. Computer Simulation and Modeling Research；2. incoherent scattering Software Radar validation test:3. incoherent scattering radar validation test；4. according to Computer Simulation and actual detection result, Optimal improvements radar return numerical model, parameter extraction algorithm and experimental method.It is of the invention can simultaneously the high-precision electronic density of the whole layer height of quick obtaining, electron temperature, ion temperature, perpendicular to parameters such as magnetic line of force direction Plasma drift velocities.
Description
Technical field
The present invention relates to a kind of incoherent scattering radar differential phase detection method, it is adaptable to ionosphere incoherent scattering thunder
Up to the incoherent scattering sounding under relatively low state of signal-to-noise to space plasma target.
Background technology
Incoherent scattering sounding refers to electromagnetic wave in ionosphere due to by the random thermal fluctuation shadow of quasi-equilibrium electron density
Ring and cause scattering, receive this energy to obtain the ionospheric probing method of Ionospheric physics parameter.Traditional ISR detections
Method is the power spectrum or auto-correlation function of the tested heating region incoherent scattering echo of analysis, by return drill draw it is tested
The Ionospheric Parameters of heating region.Although ISR is the maximally effective equipment for measuring Ionospheric Parameters, high construction
Its extensive use is limited with operating cost.And traditional ISR Detection Techniques require higher to echo signal to noise ratio, are needed during detection
Huge transmission power and longer integration time, but under low signal-to-noise ratio environment（Such as night）Still extract less than actual parameter；And
Existing ISR Detection Techniques can only detect limited Ionospheric Parameters and region under single detective pattern, need to typically switch difference
Detection mode detect different Ionospheric Parameters and region, detection efficient is high.Therefore existing ISR Detection Techniques in the time or
Obtain Ionospheric Parameters with being spatially usually unable to continuous effective, many phenomenons in ionosphere can not all be observed, and space physics
Research need the continuous measurement of Ionospheric Parameters.Monitoring to space environment and forecast in the urgent need to new detection method, with
Strengthen high-precision quick detection ability of the incoherent scattering radar under Low SNR to Ionospheric Parameters, mitigate it to visiting
The dependence of survey condition, detection time and transmission power, the need for meeting PROGRESS OF IONOSPHERIC RESEARCH IN.
The general principle of incoherent scattering radar differential phase detection technology is：Incoherent scattering radar is perpendicular to the magnetic line of force
During orientation detection, the backscattering enhanced of electromagnetic wave has the composition that out of phase postpones comprising ordinary and two kinds of extraordinary.If
With a pair of orthogonal linear polarized antenna battle array detection back scattering wave field, the average work(of the echo of two kinds of different polarized antenna arrays outputs
Rate, phase difference and cross-correlation（Cross-Correlation Function, CCF）Tested region ionosphere will be included in data
The information such as electron density, electronic and ionic temperature ratio.Based on electromagnetic wave, propagation effect, incoherent scattering are managed in magneto-ionic medium
By, antenna theory, soft object radar equation etc. set up corresponding incoherent scattering radar echo values model.With corresponding fitting
Algorithm is fitted to measured data and model data, can therefrom extract electron density and electronic and ionic temperature compares parameter.Now
Echo Doppler Spectra is very narrow, and Plasma drift velocity can be extracted from Doppler frequency shift.Being aided with multiple-pulse detection can be from echo
The information such as electron temperature are extracted in power spectrum.The technology has that detection accuracy is high, speed of detection is fast, signal to noise ratio requirement is low many
Advantage, can simultaneously the high-precision ionospheric electron density of quick obtaining, electron temperature, ion temperature, perpendicular to magnetic line of force direction
The parameters such as Plasma drift velocity.
The content of the invention
Horn of plenty and the technology and method of development ionosphere incoherent scattering radar detection, meet PROGRESS OF IONOSPHERIC RESEARCH IN and space
The monitoring of environment and forecast in the urgent need to the invention provides a kind of ionosphere incoherent scattering radar differential phase detection side
Method.The present invention can be applied to the incoherent scattering sounding of space plasma target under Low SNR, both meet and work as
The demand of preceding subject study, at the same meet PROGRESS OF IONOSPHERIC RESEARCH IN and space environment monitoring and forecast in the urgent need to.
The present invention based on emulating the motion state of different charged particles in magnetization plasma, and consider its interaction and
Constellation effect, builds scattering spectrum model；Scattering spectra modeling when being detected perpendicular to the magnetic line of force takes into full account Coulomb collision effect, adopts
With suitable model or method, emulation ion scattering spectrum and electron scattering spectrum；The scattering spectra of the different ions such as oxygen, hydrogen, helium is emulated,
Model is considered as the comprehensive effect of different ions composition.Incoherent scattering radar is sent out with Appleton-Hartree is theoretical
Propagation effect of the electromagnetic wave penetrated and received in ionosphere is analyzed, and take into full account anisotropic ionosphere magnetic etc. from
Daughter characteristic；Study the electromagnetic wave influence of propagation effect for radar antenna battle array antenna pattern in magneto-ionic medium.Utilize
Ambiguity function theory carries out waveform analysis research.Set up contacting and corresponding between ambiguity function and target optimal detection waveform
Index.For different space plasma detection demands invented the most suitable, optimal difference phase scheme detection waveform and
Its parameter, so that the problem of solving under relatively low state of signal-to-noise to space plasma target.
The present invention is comprised the following steps that：
1. Computer Simulation and Modeling Research：
（1）Radar waveform analysis is carried out using ambiguity function theory, demand is detected for different space plasmas, obtains
To detection waveform the most suitable；
（2）Using Fokker-Planck model emulation ion scattering spectrums, suitable electron scattering spectrum emulation side has been obtained
The simulated scatter spectrum of method and different ions；
（3）With the theoretical electromagnetic waves launched incoherent scattering radar and received of Appleton-Hartree in ionization
Propagation effect in layer is analyzed, and exploitation obtains corresponding computer program and emulated；
2. incoherent scattering Software Radar validation test:
（1）With soft object radar equation to incoherent scattering radar echo values model modeling, obtain it is different detection away from
From the echo power section model of the echo signal power of lower polarization reception passage in the same direction output, and obtained different detections away from
From the echo differential phase section model of the cross-correlation function of lower cross polarization receiving channel output signal；
（2）With iterative algorithms such as least square methods, the physical parameter of tested heating region is obtained, by calculating back
The doppler spectral of ripple signal is drawn accurately perpendicular to magnetic line of force direction Plasma drift velocity, is extracted from echo power spectrum
The information such as electron temperature；
3. incoherent scattering radar validation test：Data are obtained using radar equipment, Ionospheric Parameters are extracted；And will be a variety of
The result of detection of equipment is contrasted, to verify its correctness；
4. according to Computer Simulation and actual detection result, Optimal improvements radar return numerical model, parameter extraction are calculated
Method and experimental method.
Verify that whether normal waveform and whole radar system each several part work by closed-loop experiment, adjustment waveform parameter is improved
Waveform Design, calibrates radar system partial parameters, so as to provide echo-signal relevant peaks.
The detecting function and technical indicator of Detection Techniques and echo processing techniques are verified by open loop experiment, so as to detection
As a result analyzed, propose improvement project, further improve and improve Detection Techniques and echo processing techniques.
Compared to existing incoherent scattering radar detection method, ionosphere incoherent scattering radar differential phase of the invention
Detection method can simultaneously the high-precision electronic density of the whole layer height of quick obtaining, electron temperature, ion temperature, perpendicular to
The parameters such as magnetic line of force direction Plasma drift velocity.The inventive technique has that detection accuracy is high, speed of detection is fast, signal to noise ratio will
Seek low plurality of advantages, it is adaptable to the incoherent scattering sounding of space plasma target.The inventive technique enhances incoherent
High-precision quick detection ability of the scatter radar under Low SNR for Ionospheric Parameters, and reduce to a certain extent
Its operating cost, technology and method that is abundant and having developed ionosphere incoherent scattering radar detection, meet PROGRESS OF IONOSPHERIC RESEARCH IN and
The monitoring of space environment and forecast in the urgent need to possessing important scientific value and Practical significance.
Brief description of the drawings
Fig. 1 is flow chart of the invention.
Fig. 2 is detection system closed-loop experiment schematic diagram of the present invention.
Embodiment
Embodiment 1
As shown in figure 1, ionosphere incoherent scattering radar differential phase detection method, is comprised the following steps that：
1. Computer Simulation and Modeling Research：
（1）Radar waveform analysis is carried out using ambiguity function theory, and is counted accordingly using software developments such as matlab
Its fuzzy graph of calculation machine procedure simulation.Demand is detected for different space plasmas, detection waveform the most suitable is found.
（2）Motion state based on different charged particles in magnetization plasma, and consider its interaction and cluster effect
Should, incoherent scattering spectrum is emulated；Scattering spectra when being detected perpendicular to the magnetic line of force should take into full account Coulomb collision effect, can
Using Fokker-Planck model emulation ion scattering spectrums, with suitable method artificial electronic scattering spectra；Emulate oxygen, hydrogen, helium
Etc. the scattering spectra of different ions, model is considered as the comprehensive effect of different ions composition.
（3）With the theoretical electromagnetic waves launched incoherent scattering radar and received of Appleton-Hartree in ionization
Propagation effect in layer is analyzed, and takes into full account anisotropic ionosphere magnetopasma characteristic；Research electromagnetic wave exists
Influence of the propagation effect for radar antenna battle array antenna pattern in magneto-ionic medium；And develop corresponding computer program progress
Emulation.
2. incoherent scattering Software Radar validation test:
(1) with soft object radar equation to incoherent scattering radar echo values model modeling, emulate different detections away from
From the echo signal power of lower polarization reception passage output in the same direction, echo power section model is obtained；Emulate different detection ranges
The cross-correlation function of lower cross polarization receiving channel output signal, therefrom extracts the poor information of phase of echo, obtains echo difference phase
Position section model.Modeling should accurately calculate radio wave propagation, antenna polarization, scattering spectra, RCS, detection waveform, system attenuation, reception
The influence of the factors such as machine filter coefficient.
(2) is by iterative algorithms such as least square methods, by from radar in the same direction and actually measured time of cross-polarized antennas battle array
The data such as ripple mean power, phase difference and cross-correlation and model data are fitted, and obtain the accurate of tested heating region
The physical parameter such as electron density, electronic and ionic temperature ratio.Accurately hung down by calculating the doppler spectral of echo-signal and can draw
Directly in magnetic line of force direction Plasma drift velocity.The information such as electron temperature are extracted from echo power spectrum.
3. incoherent scattering radar validation test：It is the incoherent scattering Software Radar developed using our unit, great
Instrument special project Sanya incoherent scattering radar under preparation under supporting and Jicamarca incoherent scattering radars etc. are set
It is standby, data are obtained, Ionospheric Parameters are extracted.And contrasted the result of detection of plurality of devices, to verify its correctness
4. according to Computer Simulation and actual detection result, Optimal improvements radar return numerical model, parameter extraction are calculated
Method and experimental method.
(1) carries out closed-loop experiment according to Fig. 2 detection system closed test schematic diagram：
Method：Inscribed signal source, the operation of internal system signal flow.Transmitter output signal is passed through into cable, attenuator
Closed loop is input to receiver.
Purpose：Verify whether waveform and the work of whole radar system each several part are normal, adjustment waveform parameter is improved waveform and set
Meter, calibrates radar system partial parameters.
Target：Provide echo-signal relevant peaks.
(2) open loop experiments：
Method：By incoherent scattering radar perpendicular to magnetic line of force orientation detection, received with a pair of orthogonal linear polarized antenna battle array
Backscatter signal.Never same polarization aerial array output echo mean power, phase difference and cross-correlation extracting data
Tested region Ionospheric Parameters.
Purpose：Verify the detecting function and technical indicator of Detection Techniques and echo processing techniques.
Target：Result of detection is analyzed, improvement project is proposed, further improves and improve at Detection Techniques and echo
Reason method.
Claims (5)
1. ionosphere incoherent scattering radar differential phase detection method, it is characterised in that comprise the following steps that：
1st, Computer Simulation and Modeling Research：
（1）Radar waveform analysis is carried out using ambiguity function theory, demand is detected for different space plasmas, obtains most
For suitable detection waveform；
（2）Using Fokker-Planck model emulation ion scattering spectrums, obtained suitable electron scattering spectrum emulation mode and
The simulated scatter spectrum of different ions；
（3）With the theoretical electromagnetic waves launched incoherent scattering radar and received of Appleton-Hartree in ionosphere
Propagation effect analyzed, and develop and obtain corresponding computer program and emulated；
2nd, incoherent scattering Software Radar validation test:
（1）With soft object radar equation to incoherent scattering radar echo values model modeling, obtain under different detection ranges
The echo power section model of the echo signal power of polarization reception passage output in the same direction, and obtained under different detection ranges
The echo differential phase section model of the cross-correlation function of cross polarization receiving channel output signal；
（2）With least square method iterative algorithm, the physical parameter of tested heating region is obtained, by calculating echo-signal
Doppler spectral draw accurately perpendicular to magnetic line of force direction Plasma drift velocity, extract electronics temperature from echo power spectrum
Degree, ion temperature information；
3rd, incoherent scattering radar validation test：Data are obtained using radar equipment, Ionospheric Parameters are extracted；And by plurality of devices
Result of detection contrasted, to verify its correctness；
4th, according to Computer Simulation and actual detection result, Optimal improvements radar return numerical model, parameter extraction algorithm and reality
Proved recipe method.
2. incoherent scattering radar differential phase detection method in ionosphere according to claim 1, it is characterised in that：Step
In 4, verify that whether normal waveform and whole radar system each several part work by closed-loop experiment, adjustment waveform parameter improves waveform
Design, calibrates radar system partial parameters, so as to provide echo-signal relevant peaks.
3. incoherent scattering radar differential phase detection method in ionosphere according to claim 1, it is characterised in that：Step
In 4, the detecting function and technical indicator of Detection Techniques and echo processing techniques are verified by open loop experiment, so as to result of detection
Analyzed, propose improvement project, further improve and improve Detection Techniques and echo processing techniques.
4. incoherent scattering radar differential phase detection method in ionosphere according to claim 2, it is characterised in that：Closed loop
Experimental method is：Inscribed signal source, internal system signal flow operation, transmitter output signal is closed by cable, attenuator
Ring is input to receiver.
5. incoherent scattering radar differential phase detection method in ionosphere according to claim 3, it is characterised in that：Open loop
Experimental method is：By incoherent scattering radar perpendicular to magnetic line of force orientation detection, after being received with a pair of orthogonal linear polarized antenna battle array
To mean power, phase difference and the cross-correlation extracting data quilt of scattered signal, the never echo of same polarization aerial array output
Survey region Ionospheric Parameters.
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| CN108181624B (en) * | 2017-12-12 | 2020-03-17 | 西安交通大学 | Difference calculation imaging device and method |
| CN108254730B (en) * | 2018-04-11 | 2021-07-20 | 西安电子科技大学 | Radar zero-time-delay autocorrelation function processing method based on damping fitting |
| WO2020003513A1 (en) * | 2018-06-29 | 2020-01-02 | 三菱電機株式会社 | Radar device |
| CN110927687B (en) * | 2019-11-09 | 2022-05-03 | 中国电波传播研究所（中国电子科技集团公司第二十二研究所） | Meteor detection method based on incoherent scattering radar |
| CN111580061B (en) * | 2020-05-20 | 2020-10-27 | 中国科学院地质与地球物理研究所 | Ionized layer electron density inversion method based on CLEAN algorithm |
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