CN109633578A - A kind of binary channels high-precision phase position Calibration System and method - Google Patents
A kind of binary channels high-precision phase position Calibration System and method Download PDFInfo
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- CN109633578A CN109633578A CN201811466632.1A CN201811466632A CN109633578A CN 109633578 A CN109633578 A CN 109633578A CN 201811466632 A CN201811466632 A CN 201811466632A CN 109633578 A CN109633578 A CN 109633578A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
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Abstract
The present invention is a kind of binary channels high-precision phase position Calibration System, and feature includes: rate-aided signal source, internal calibration component, analog receiver, ADC signal acquisition and signal processing system；The rate-aided signal source output two-way rate-aided signal is injected in the internal calibration component, and internal calibration component exports two-way calibration signal and is transmitted to the analog receiver by cable；Received signal is transmitted to ADC signal acquisition and handled with signal processing system by the analog receiver, obtains total phase difference of two paths of signals；By part received signal along backtracking to internal calibration component, the signal of return is transmitted to ADC signal acquisition and signal processing system again, extracts the phase difference of cable itself analog receiver by internal calibration component simultaneously.The present invention proposes a kind of binary channels high-precision phase position Calibration Method, carries out calibration to the phase error between more receives links, and eliminate the phase error of connecting cable simultaneously, calibration precision is up to 0.07 °.
Description
Technical field
The present invention relates to interferometer radar technical field more particularly to a kind of twin-channel phase calibration technologies.
Background technique
The terrian elevation measurement precision of interferometer radar system is influenced by many interferometric parameter errors, and error source is mainly wrapped
Include instrument error, propagation in atmosphere error, orbit error, geophysics error, data processing error etc..These error source sources are more
Sample and influence it is different, by taking countermeasure to be evaded or being compensated, can effectively promote entire height-finding system
Performance.
In above-mentioned various influence factors, the influence of error caused by system itself is more serious.Since temperature is floated
The reasons such as shifting, aging, electromagnetic interference, the amplitude-frequency and phase-frequency characteristic of system can generate variation, thus can introduce altimetry error, because
This, needs to take some technological means to be monitored to the response characteristic of system itself and calibration work.
The mode for generalling use system internal calibration has an impact its interferometric phase in the interferometer radar course of work
It is the phase characteristic in receives link, by the phase of real-time monitoring receives link, to demarcate the phase difference value between receiving channel,
And think that this difference is stable within a certain period of time, thus the phase error of system is calibrated to come, and to each reception
Link compensates, and interferometric phase measurement accuracy is improved, to improve ground elevation inversion accuracy.
In phase Calibration Method and application aspect, satellite-borne synthetic aperture radar ERS-1/2 in orbit and
Radarsat, which is designed, default mark system.Wherein, the internal calibration circuit of ERS-1/2 is that feed-in will receive after emitting signal delay
Circuit measures the stability of entire circuit transmission power and the stability of receiver gain.Radarsat is then without postponing back
Road, but transmitting signal is sent by way of coupling and receives circuit.Domestic HJ-1-C satellite equally uses internal calibration
System, using altogether includes calibrating three kinds of internal calibration modes with reference to calibration, transmitting calibration, noise.But the said goods are single-passes
Road SAR system is not dual channel system, and the case where be directed to single channel receives link, is different from multi-pass described in this patent
The mode of the phase calibration in road.
In terms of the patent of phase Calibration Method, Qiao Ming, Liang Xingdong of CAS Electronics Research Institute, Ding Chibiao,
A kind of wideband synthetic aperture radar of the patent-of Zhang Peijie, Han Bing active externally coefficient potentiometer and its calibrating method (publication number:
CN101082670), which is a kind of externally coefficient potentiometer and its calibrating method, it is therefore an objective to improve active calibration receive-transmit system
Gain, obtains biggish radar cross section, is not related to the phase calibration of interferometer radar system.BJ University of Aeronautics & Astronautics it is old
Outstanding person, a kind of satellite carried SAR inner marking signal processing platform system of patent-of Yang Wei, Wang Pengbo, Zhou Yinqing, Li Chunsheng and realization side
Method (publication number: CN101135726), the patent of invention disclose a kind of satellite carried SAR inner marking signal processing platform system and reality
Existing method, its process object are satellite carried SAR inner marking signal, and valid data abstraction module is to effectively interior when passing through input signal
The output result of the extraction of rate-aided signal and certificate authenticity module to stability scaling module, phase error scaling module
Card is reflected in comparison, handles internal calibration signal using the working method of collaboration parallel processing.But the patent is only applicable to SAR system,
The phase difference value between binary channels cannot be obtained, therefore is not suitable for interferometer radar system.CAS Electronics Research Institute
The external calibration method (publication number: CN103364766A) of the spaceborne InSAR system of the patent-of Wang Yu, Ding Chibiao, Liang Xingdong, this hair
It is bright to disclose a kind of external calibration method of spaceborne InSAR system.The external calibration method includes: to measure sea height by satellite altimeter
Degree evidence obtains mean sea level altitude information after removing it time-varying influence factor；By spaceborne InSAR system obtain it is default when
Between and spatial distribution ocean imagery to uncertain target interferometric parameter, obtain the sea level height number of spaceborne InSAR systematic survey
According to；Time-varying influence factor bring sea level height of simulation calculation under the conditions of preset time and spatial distribution in addition to propagation effect
Variation；Time-varying influence factor bring sea level height variation by mean sea level height and in addition to propagation effect, obtains time-varying and closes
At sea level height data；It is high to the sea of spaceborne InSAR systematic survey using time-varying synthesis sea level height data as normal data
Degree realizes the calibration of spaceborne InSAR system according to being corrected.The patent is the external calibration side to the sea InSAR height-finding system
Method is to be corrected to the sea level height data of spaceborne InSAR systematic survey, is not related to the calibration of phase.
Traditional InSAR interference system, since the calibration precision to phase is not high, the phase calibration of interchannel is not accounted for
The phase difference for calibrating the connecting cable in component influences, so without relevant patent.
So far, without the patent of binary channels high-precision phase position Calibration Method described in this patent.
Summary of the invention
The present invention provides a kind of binary channels high-precision phase position Calibration Method, marks to the phase difference of interference receives link
It is fixed, guarantee the altimetry precision of entire radar altitude meter systems with this.
In order to achieve the above object, the present invention provides a kind of binary channels phase Calibration System, includes: rate-aided signal source, interior
Calibrate component, analog receiver, ADC signal acquisition and signal processing system；
The rate-aided signal source output two-way rate-aided signal is injected in the internal calibration component, and internal calibration component exports two-way
Calibration signal is transmitted to the analog receiver by cable；
Received signal is transmitted to ADC signal acquisition and handled with signal processing system by the analog receiver, is obtained
Total phase difference of two paths of signals；
By part received signal along backtracking to internal calibration component, internal calibration component will return analog receiver simultaneously
Signal be transmitted to again ADC signal acquisition and signal processing system, extract cable itself phase difference.
Preferably, analog receiver receiving port is influenced by standing wave, the part signal edge that internal calibration component is sent
Backtracking is to internal calibration component.
Preferably, internal calibration component is connect by radio frequency connecting cable with analog receiver.
Preferably, the internal calibration component also includes circulator and down coversion link；
The circulator setting exports two-way calibration signal to analog receiver at internal calibration component calibration mouth, and
The signal returned from analog receiver is sent into the down coversion link of internal calibration component, and signal is transmitted to ADC letter again by down coversion link
Number acquisition and signal processing system.
A kind of binary channels high-precision phase position Calibration Method, step includes:
Step 1, the total phase difference for obtaining two paths of signals；
Step 2, the phase difference for extracting cable itself；
Step 3, the phase difference that cable itself is rejected from total phase difference；
Step 4, above-mentioned steps measurement are multiple, averaged.
Preferably, also inconsistent to two paths of signals amplitude in the step 2 other than extracting the phase difference of cable itself
Property compensates.
Preferably, it is assumed that the inconsistency of two paths signal be over the whole width it is constant, then digital receiver is being just
Hand over the complex signal in two channels demodulated successively as follows:
Wherein, formula (1) is main channel, and formula (2) is subaisle；
To subaisle echo-signal s02Do following operation just；
Wherein,
s01×s02 *=(I01+jQ01)×(I02-jQ02)=[I01I02+Q01Q02]+j[I02Q01+I01Q02] (4)
So compensation factor is
Amplitude-phase consistency correction is completed by the above process.
Compared with prior art, the present invention having the advantage that
1, calibration precision is high: the calibration precision of phase error is up to 0.07 °.
2, construction is succinct, is easy to be engineered: the method for the invention passes through the transmitting-receiving of internal calibration component combination interferometer radar
System, the situation of change of the phase characteristic between real-time monitoring receives link, is easy to be engineered.
Detailed description of the invention
Fig. 1 is system structure diagram of the invention；
Fig. 2 is working-flow figure of the invention.
Specific embodiment
In order to be easy to understand the technical means, the creative features, the aims and the efficiencies achieved by the present invention, tie below
Closing the drawings and specific embodiments, the present invention will be further described in detail, the range of but do not limit the invention in any way.
As shown in attached drawing 1, attached drawing 2, present system includes: rate-aided signal source, internal calibration component, analog receiver,
ADC signal acquisition and signal processing system；
The rate-aided signal source output two-way rate-aided signal is injected in the internal calibration component；
The internal calibration component also includes circulator and down coversion link；
The circulator setting is exported at internal calibration component calibration mouth, by two-way calibration signal by radio frequency connecting cable
To analog receiver, received signal is transmitted to ADC signal acquisition and handled with signal processing system by the analog receiver,
The total phase difference measurement for obtaining two paths of signals is multiple, averaged, so that it may which the stationary phase for obtaining interference receiving channel is missed
Difference compensates calibration to subsequent reception signal, to reduce Interferometric phase error.
Analog receiver receiving port is influenced by standing wave simultaneously, by part received signal along backtracking to internal calibration
Component, and the signal returned from analog receiver is sent into the down coversion link of internal calibration component, down coversion link is transmitted to ADC letter again
Number acquisition and signal processing system, extract cable itself phase difference.
Since the shake of two radio frequency connecting cables, temperature change influence are different, radio frequency connecting cable itself is caused to draw
The phase difference risen is changing, this phase difference can be superimposed upon in twin-channel Interferometric phase error, to cause shadow to interferometric phase
It rings, it is therefore necessary to calibration be synchronized to the phase difference of radio frequency connecting cable and rejected.
For actual application: for two interference receives links, it is assumed that radio frequency link length, temperature change etc. cause
The equivalent path length of receives link be respectively R1、R2, the two-way input that internal calibration component is injected into two receives links, which is calibrated, to be believed
, will be different in the phase of output end number behind the two different paths, it is reference data with receives link 1, then connects
Receiving the phase difference between link 2 and receives link 1 is Δ φ1=2 π (R1-R2(one way, λ are generally taken as the center frequency of passband to)/λ
λ at rate), it is handled by echo acquirement and back end signal, carries out phase extraction and obtain Δ φ1.Since internal calibration component is infused
The two-way calibration signal entered to two receives links is transmitted by radio frequency connecting cable, and there is also phases for radio-frequency cable itself
Difference, it is necessary to be demarcated and be rejected.
Assuming that radio frequency connecting cable length is respectively L1、L2If cable length is taken into account, two receives links etc.
Imitating path length is respectively R1+L1、R2+L2, then the phase difference between two receives links is Δ φ1π (the R of '=21-R2)/λ+2π
(L1-L2)/λ, wherein 2 π (L1-L2)/λ is the phase error for needing to eliminate, and the above process can not directly demarcate L1、L2Caused phase
Potential difference needs the calibration signal for exporting internal calibration component to carry out independent calibration back to internal calibration component, therefore in internal calibration
Circulator is added in assembly circuit, after calibration signal passes through radio-frequency cable, due to the influence of standing wave at analog receiver, part is believed
The down coversion link for number returning to internal calibration component, carries out down coversion, acquisition and back end signal are handled, so that it may obtain radio frequency electrical
Cable L1、L2Caused 2 π (L of phase difference1-L2)/λ, then eliminating 2 π (L1-L2After the influence of)/λ, 2 π (R1-R2)/λ is just used as two
Phase calibration values between receives link.When processing, same broadband signal is inputted to two receives links, to all receiving channels
Output signal be acquired and handled, obtain phase difference, measurement repeatedly, averaged, so that it may obtain channel it
Between phase error calibration is compensated to subsequent reception signal as phase compensation value.
In addition to the compensation of phase error, it is also necessary to amplitude inconsistency is compensated, it is general to be calibrated simultaneously, with
For the amplitude-phase consistency correction in two channels, it is assumed that the inconsistency of two paths signal be over the whole width it is constant,
The complex signal in two channels that then digital receiver quadrature demodulation goes out is successively as follows:
Wherein, formula (1) is main channel, and formula (2) is subaisle；
To subaisle echo-signal s02Do following operation just；
Wherein,
s01×s02 *=(I01+jQ01)×(I02-jQ02)=[I01I02+Q01Q02]+j[I02Q01+I01Q02] (4)
So compensation factor is
Amplitude-phase consistency correction is completed by the above process.
It is discussed in detail although the contents of the present invention have passed through above-mentioned preferred embodiment, but it should be appreciated that above-mentioned retouches
It states and is not considered as limitation of the invention.After those skilled in the art have read above content, for of the invention a variety of
Modifications and substitutions all will be apparent.Therefore, protection scope of the present invention should be by the attached claims.
Claims (7)
1. a kind of binary channels high-precision phase position Calibration System is, characterized by comprising: rate-aided signal source, internal calibration component, simulation
Receiver, ADC signal acquisition and signal processing system；
The rate-aided signal source output two-way rate-aided signal is injected in the internal calibration component, and internal calibration component exports two-way calibration
Signal is transmitted to the analog receiver by cable；
Received signal is transmitted to ADC signal acquisition and handled with signal processing system by the analog receiver, obtains two-way
Total phase difference of signal；
Analog receiver is by part received signal along backtracking to internal calibration component simultaneously, and internal calibration component is by the letter of return
It number is transmitted to ADC signal acquisition and signal processing system again, extracts the phase difference of cable itself.
2. a kind of binary channels high-precision phase position Calibration System as described in claim 1, which is characterized in that analog receiver receives
Port is influenced by standing wave, and the part signal that internal calibration component is sent is along backtracking to internal calibration component.
3. a kind of binary channels high-precision phase position Calibration System as described in claim 1, which is characterized in that internal calibration component passes through
Radio frequency connecting cable is connect with analog receiver.
4. a kind of binary channels high-precision phase position Calibration System as described in claim 1, which is characterized in that the internal calibration component
It also include circulator and down coversion link；
Circulator setting exports two-way calibration signal to analog receiver at internal calibration component calibration mouth, and from mould
The signal that quasi- receiver returns is sent into the down coversion link of internal calibration component, and signal is transmitted to ADC signal again and adopted by down coversion link
Collection and signal processing system.
5. a kind of binary channels high-precision phase position Calibration Method, which is characterized in that utilize the described in any item one kind of claim 1-4
Binary channels high-precision phase position Calibration System, step includes:
Step 1, the total phase difference for obtaining two paths of signals；
Step 2, the phase difference for extracting cable itself；
Step 3, the phase difference that cable itself is rejected from total phase difference；
Step 4, above-mentioned steps measurement are multiple, averaged.
6. a kind of binary channels high-precision phase position Calibration Method as claimed in claim 5, which is characterized in that removed in the step 2
Except the phase difference for extracting cable itself, also two paths of signals amplitude inconsistency is compensated.
7. a kind of binary channels high-precision phase position Calibration Method as claimed in claim 6, which is characterized in that assuming that two paths are believed
Number inconsistency be over the whole width it is constant, then digital receiver quadrature demodulation go out two channels complex signal successively
It is as follows:
Wherein, formula (1) is main channel, and formula (2) is subaisle；
To subaisle echo-signal s02Do following operation just；
Wherein,
s01×s02 *=(I01+jQ01)×(I02-jQ02)=[I01I02+Q01Q02]+j[I02Q01+I01Q02] (4)
So compensation factor is
Amplitude-phase consistency correction is completed by the above process.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110554366A (en) * | 2019-09-02 | 2019-12-10 | 北京电子工程总体研究所 | Method and device for automatically calibrating amplitude-phase consistency of seeker |
| CN110907887A (en) * | 2019-10-21 | 2020-03-24 | 成都大公博创信息技术有限公司 | Super-resolution direction-finding device based on uniform circular array and processing system |
| CN112068086A (en) * | 2020-10-17 | 2020-12-11 | 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） | Shore-based multi-channel radar amplitude-phase correction method based on external calibration test data |
| CN112698282A (en) * | 2020-12-11 | 2021-04-23 | 中国科学院空天信息创新研究院 | Internal calibration device and internal calibration method for DBF satellite-borne SAR system |
| CN113644992A (en) * | 2021-08-11 | 2021-11-12 | 中国电子科技集团公司第十四研究所 | Method for measuring phase of internal calibration network |
| CN113687446A (en) * | 2021-07-19 | 2021-11-23 | 西安空间无线电技术研究所 | Near-field external calibration method based on satellite-borne synthetic aperture microwave radiometer |
| CN113702932A (en) * | 2021-08-27 | 2021-11-26 | 上海无线电设备研究所 | Height finding radar calibration system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101915909A (en) * | 2010-08-11 | 2010-12-15 | 四川九洲电器集团有限责任公司 | Implementing method for calibrating amplitude and phase of system receiving channel |
| CN103595404A (en) * | 2013-10-29 | 2014-02-19 | 中国电子科技集团公司第四十一研究所 | Frequency mixer group delay measuring circuit and method |
| US8841923B1 (en) * | 2007-08-30 | 2014-09-23 | Agilent Technologies, Inc. | Device and method for performing remote frequency response measurements |
| CN104391187A (en) * | 2014-09-18 | 2015-03-04 | 中国人民解放军63892部队 | Alignment calibration device and alignment calibration method of multi-frequency-point antenna array |
| CN106199188A (en) * | 2016-07-20 | 2016-12-07 | 中国科学院紫金山天文台 | A kind of device and method utilizing the change of removal cable phase place in circulator calibration vector field measurement |
-
2018
- 2018-12-03 CN CN201811466632.1A patent/CN109633578B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8841923B1 (en) * | 2007-08-30 | 2014-09-23 | Agilent Technologies, Inc. | Device and method for performing remote frequency response measurements |
| CN101915909A (en) * | 2010-08-11 | 2010-12-15 | 四川九洲电器集团有限责任公司 | Implementing method for calibrating amplitude and phase of system receiving channel |
| CN103595404A (en) * | 2013-10-29 | 2014-02-19 | 中国电子科技集团公司第四十一研究所 | Frequency mixer group delay measuring circuit and method |
| CN104391187A (en) * | 2014-09-18 | 2015-03-04 | 中国人民解放军63892部队 | Alignment calibration device and alignment calibration method of multi-frequency-point antenna array |
| CN106199188A (en) * | 2016-07-20 | 2016-12-07 | 中国科学院紫金山天文台 | A kind of device and method utilizing the change of removal cable phase place in circulator calibration vector field measurement |
Non-Patent Citations (2)
| Title |
|---|
| LINZHU YUE: "The Cable Phase Difference Detection of Very High Frequency (VHF) Antenna Array Based on Ad8302", 《2016 3RD INTERNATIONAL CONFERENCE ON INFORMATION SCIENCE AND CONTROL ENGINEERING (ICISCE)》 * |
| 吴捷: "多通道接收机幅相校准测试系统的设计", 《现代雷达》 * |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110554366A (en) * | 2019-09-02 | 2019-12-10 | 北京电子工程总体研究所 | Method and device for automatically calibrating amplitude-phase consistency of seeker |
| CN110907887A (en) * | 2019-10-21 | 2020-03-24 | 成都大公博创信息技术有限公司 | Super-resolution direction-finding device based on uniform circular array and processing system |
| CN110907887B (en) * | 2019-10-21 | 2021-02-23 | 成都大公博创信息技术有限公司 | Super-resolution direction-finding processing system based on uniform circular array |
| CN112068086A (en) * | 2020-10-17 | 2020-12-11 | 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） | Shore-based multi-channel radar amplitude-phase correction method based on external calibration test data |
| CN112068086B (en) * | 2020-10-17 | 2022-03-01 | 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） | Shore-based multi-channel radar amplitude-phase correction method based on external calibration test data |
| CN112698282A (en) * | 2020-12-11 | 2021-04-23 | 中国科学院空天信息创新研究院 | Internal calibration device and internal calibration method for DBF satellite-borne SAR system |
| CN112698282B (en) * | 2020-12-11 | 2023-06-13 | 中国科学院空天信息创新研究院 | Internal calibration device and internal calibration method for DBF (digital binary field) satellite-borne SAR (synthetic aperture radar) system |
| CN113687446A (en) * | 2021-07-19 | 2021-11-23 | 西安空间无线电技术研究所 | Near-field external calibration method based on satellite-borne synthetic aperture microwave radiometer |
| CN113687446B (en) * | 2021-07-19 | 2024-02-09 | 西安空间无线电技术研究所 | Near field external calibration method based on satellite-borne synthetic aperture microwave radiometer |
| CN113644992A (en) * | 2021-08-11 | 2021-11-12 | 中国电子科技集团公司第十四研究所 | Method for measuring phase of internal calibration network |
| CN113702932A (en) * | 2021-08-27 | 2021-11-26 | 上海无线电设备研究所 | Height finding radar calibration system |
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