CN110146859B - Method and device for radar scattering cross section RCS calibration - Google Patents

Method and device for radar scattering cross section RCS calibration Download PDF

Info

Publication number
CN110146859B
CN110146859B CN201910455642.3A CN201910455642A CN110146859B CN 110146859 B CN110146859 B CN 110146859B CN 201910455642 A CN201910455642 A CN 201910455642A CN 110146859 B CN110146859 B CN 110146859B
Authority
CN
China
Prior art keywords
radar
rcs
satellite
calibration
measurement
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.)
Active
Application number
CN201910455642.3A
Other languages
Chinese (zh)
Other versions
CN110146859A (en
Inventor
杨萍
慈颖
陈浩
党宏杰
邓洛凤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
63921 Troops of PLA
Original Assignee
63921 Troops of PLA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 63921 Troops of PLA filed Critical 63921 Troops of PLA
Priority to CN201910455642.3A priority Critical patent/CN110146859B/en
Publication of CN110146859A publication Critical patent/CN110146859A/en
Application granted granted Critical
Publication of CN110146859B publication Critical patent/CN110146859B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • G01S7/40—Means for monitoring or calibrating
    • 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
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

The invention provides a method and a device for radar scattering cross section RCS calibration, wherein the method comprises the following steps: performing RCS measurements on a satellite having an incompletely regular profile formed by loading radar reflector loads having a regular geometric profile on a satellite platform to form an RCS two-dimensional data table, and calibrating RCS measurement K values using radar equations in conjunction with the RCS two-dimensional data table. By utilizing the technical scheme of the invention, a space-based RCS calibration standard can be provided for the ground multi-band pulse radar, and compared with the traditional ball-playing calibration mode, the method has obvious economic effect.

Description

Method and device for radar scattering cross section RCS calibration
Technical Field
The present invention relates generally to the field of radar measurement technology. More particularly, the present invention relates to Radar scattering Cross Section ("RCS") calibration and systematic error calibration techniques.
Background
The RCS of the target reflects the scattering ability of the target on the radar irradiation electromagnetic wave and is an important parameter of the target characteristic. The target RCS is measured by a ground reflection radar, and the precision of a measuring result is closely related to the calibration precision of radar equipment. The target RCS measurement is a process of converting the echo power of a radar receiver by using a radar equation, and is generally divided into an absolute calibration method and a relative calibration method, and the relative calibration method is generally adopted at present. The method comprises the basic process that the relation between the echo power of a target to be detected and the echo power of a reference target is established through calibrating an accurate RCS reference target, and the RCS of the target to be detected is calculated.
To reduce the RCS error value of the reference target, the reference target currently generally employs a metal reflector with a regular geometric shape, most typically a spherical shape, to ensure that the target RCS is independent of the observation attitude. The prior method for calibrating RCS (Rich research institute of air force and Equipment), published in 12.2011, volume 5, phase 6, pages 11 to 13, discloses a method for calibrating RCS (Rich concrete System) by using regular geometric bodies in the world at present, wherein the most typical method is an LCS (Long service Scale) series calibration satellite which is a hollow aluminum ball with the thickness of about 3.2mm and the diameter of 1.12m, and the optical reflection section of the satellite is constant to pi R no matter what attitude angle is observed2＝1m2. The calibration satellite has the characteristics that the satellite does not have a conventional satellite platform, the calibration body is the satellite, and the attitude and the orbit of the calibration body are not controllable. However, if a conventional satellite platform is added for operation and control, the calibration body is damagedThe original target characteristic, the traditional RCS calibration method is not applicable any more.
Disclosure of Invention
The invention mainly overcomes the defect that a calibration body is added with a satellite platform, and provides a radar RCS calibration method by using an incomplete regular shape satellite.
In one aspect, the present invention provides a method for radar scattering cross-section RCS calibration, comprising: performing RCS measurements on a satellite to form an RCS two-dimensional data table, wherein the satellite has an incompletely regular profile formed by loading a radar reflector load having a regular geometric profile onto a satellite platform; and calibrating the RCS measurement K value by using a radar equation and combining an RCS two-dimensional data table.
In one embodiment, wherein RCS measurements are performed on a satellite based on measurement signals comprising a combination of at least frequency and polarization and measurement attitude, the measurement attitude is sampled over a range of calibration angles available from the radar reflector load, the attitude angles including azimuth and elevation dimensions.
In one embodiment, the K value is scaled using the following equation (1):
Figure BSA0000183424850000021
Ps: radar echo power;
Pr: radar transmission power:
r: the distance between the radar and the calibration body;
g: gain of the radar antenna;
σ: the reflection section of the whole satellite of the satellite;
θ, φ: the azimuth angle and the pitch angle of the satellite under the radar observation coordinate system are respectively.
The values of sigma (theta, phi) are obtained from a look-up table, G, PrIs a constant value, PsR is acquired by radar.
In another embodiment, the K value is averaged using the following equation (2):
Figure BSA0000183424850000031
wherein i represents the ith sample, and when i is more than 100, the arithmetic mean value is taken as the final result.
In one embodiment, the satellite platform has a symmetrical, regular shape.
In yet another aspect, the present invention provides an apparatus for radar scattering cross-section RCS calibration, comprising: radar reflector loads having a regular geometric shape; a satellite platform for carrying the radar reflector load and forming an incomplete regular shape when the radar reflector load is carried on the satellite platform, wherein the radar reflector load is configured to receive illuminating electromagnetic waves from a ground radar to assist in calibrating the RCS measurement K-values, wherein calibrating comprises calibrating the RCS measurement K-values using radar equations and in conjunction with a RCS two-dimensional data table obtained by performing RCS measurements on a satellite.
After the work is finished, the K value or the average value of K after multiple measurements can be bound into the radar and used as the parameter after calibration.
The traditional calibration mode is ball placement or airplane calibration, the ball placement is influenced by weather, the airplane calibration organization is difficult to implement, the economic cost is high, and the timeliness is not strong. Through the satellite calibration mode, have full weather, the real-time characteristics of being available, compare traditional mode, economy, high efficiency.
Drawings
The invention and its advantages will be better understood by reading the following description, provided by way of example only, and made with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a satellite of a less than perfect regular shape according to an embodiment of the present invention;
FIG. 2 is a schematic illustration of attitude angles according to an embodiment of the invention; and
fig. 3 is a flow chart of a method for radar cross section RCS calibration according to an embodiment of the present invention.
Detailed Description
The invention mainly overcomes the defect that a calibration body is loaded on a satellite platform, and provides a scheme for carrying out radar RCS calibration by using an incomplete regular shape satellite. Specifically, the technical scheme adopted by the invention relates to the establishment of the accurate corresponding relation between the signal form, the target attitude and the calibration body RCS through the precision calibration of the ground in advance, and the influence caused by the fact that the reflection characteristic of the calibration body is damaged by a satellite platform is overcome. When the radar reaches the standard, the RCS of the calibration body is not a constant value any more, but a variable which changes along with the attitude, and the accurate RCS of the target is determined by utilizing the corresponding relation between the attitude of the target and the RCS, so that the calibration is completed. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a satellite of a less than perfect regular shape according to an embodiment of the present invention. As shown in fig. 1, the incomplete regular-profile satellite 100 includes a satellite platform 101 and a calibration body (i.e., radar reflector load) 102. In one embodiment, the satellite platform may be a cylinder, a cube (as shown in fig. 1), or the like with a symmetrical and regular shape to have a symmetrical shape as much as possible, so as to reduce the workload of ground calibration. Meanwhile, the overall dimension of the satellite platform should be as small as possible so as to reduce the damage to the calibration body RCS. In one embodiment, the calibration body 102 may be a calibration sphere with the largest diameter as possible on the premise that the launch vehicle can be carried, thereby reducing the influence of the satellite platform on the whole-satellite RCS.
FIG. 2 is a schematic illustration of attitude angles according to an embodiment of the invention. As shown in fig. 2, (the origin of coordinates is at the center of mass of the satellite, the x-axis is consistent with the direction of the satellite velocity, the y-axis is directed to the ground, the z-axis is consistent with the right-hand coordinate system, the theta angle is the angle between the incident direction of the radar and the projection on the xy plane and the x-axis,
Figure BSA0000183424850000041
the angle is the angle between the radar incident direction and the xy plane).
Fig. 3 is a flow chart of a method 300 for radar scattering cross-section RCS calibration according to an embodiment of the present invention. As shown in fig. 3, at step 301, RCS measurements are performed on satellites having a non-fully regular profile formed by loading radar reflector loads having a regular geometric profile onto a satellite platform to form a RCS two-dimensional data table. At step 302, the RCS measurement K value is calibrated using radar equations in conjunction with the RCS two-dimensional data table.
In one embodiment, accurate RCS measurement is performed on the whole satellite in a ground microwave darkroom, and accurate RCS values of different signal forms and postures are obtained. During measurement, the signal form of a test signal transmitted by the simulated radar of the microwave darkroom test system is selected according to needs, the signal form comprises the working frequency and the polarization mode (horizontal polarization, vertical polarization, left-hand circular polarization and right-hand circular polarization) of the transmitted signal, and the attitude can comprise two dimensions of azimuth and pitching. In the test process, when the selection of the azimuth angle or the pitch angle cannot be continuous, an interval sampling mode can be adopted. The specific sampling interval and azimuth direction can mainly consider the symmetry of the reflection characteristic of the platform, and the pitch direction can mainly consider the angle precision of ground test equipment (a two-dimensional turntable for placing a satellite, and different postures of the satellite in flight can be simulated through the rotation of the two-dimensional turntable).
In the calibration process, the invention may use a calculation formula as an example
Figure BSA0000183424850000051
Wherein:
Ps: radar echo power;
Pr: radar transmission power:
r: the distance between the radar and the calibration body;
g: gain of the radar antenna;
σ: the reflection section of the whole satellite of the satellite;
θ, φ: the azimuth angle and the pitch angle of the satellite under the radar observation coordinate system are respectively.
The values of sigma (theta, phi) are obtained from a look-up table, G, PrIs a constant value, PsR is acquired by radar.
Further, the air conditioner is provided with a fan,
Figure BSA0000183424850000052
i represents the ith sample, and when i is sufficiently large (i > 100), the arithmetic mean is taken as the final result.
Figure BSA0000183424850000053
After the calibration operation is completed, the obtained final K can be corrected0The values are bound into a radar and used as the calibrated parameters.
In another embodiment, the accurate RCS measurement is carried out on the whole satellite within the calibration angle range provided by the satellite, the measurement signal needs to be subjected to the combination of frequency point and polarization, the measurement attitude is sampled and covered within the calibration angle range provided by the load, and the attitude angle comprises two dimensions of azimuth and elevation. After accurate measurement, for each polarization and point-frequency combination, a two-dimensional data table of accurate RCS is formed at different observation angles.
Calculating the attitude and distance of the satellite relative to the radar by using the satellite orbit and the satellite flight attitude provided by the measurement and control system;
in the calibration process, the calibration calculation formula can be used
Figure BSA0000183424850000061
And obtaining a plurality of K value samples after a plurality of observations are carried out. The RCS values of the satellite under different attitudes are obtained by using accurate RCS measurement values in a ground microwave darkroom and by adopting a table look-up mode.
For example using modified calculation formulas
Figure BSA0000183424850000062
To obtain i sample values. In the technical scheme of the invention, the continuous sampling number i is required to be not less than 100, so that the method and the device can be utilized
Figure BSA0000183424850000063
To obtain the arithmetic mean value K0。
Although the present invention is described in the above embodiments, the description is only for the convenience of understanding the present invention, and is not intended to limit the scope and application of the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (7)

1. A method for radar cross section RCS calibration, comprising:
performing RCS measurements on a satellite to form an RCS two-dimensional data table, wherein the satellite has an incompletely regular profile formed by loading a radar reflector load having a regular geometric profile onto a satellite platform; and
calibrating the RCS measurement K value by using a radar equation and combining an RCS two-dimensional data table;
wherein the K value is calibrated by the following formula (1):
Figure FSB0000192543770000011
Ps: radar echo power;
Pr: radar transmission power:
r: the distance between the radar and the calibration body;
g: gain of the radar antenna;
σ: the reflection section of the whole satellite of the satellite;
Figure FSB0000192543770000012
respectively is the azimuth angle and the pitch angle of the satellite under a radar observation coordinate system;
Figure FSB0000192543770000013
the values are obtained from a look-up table, G, PrIs a constant value, PsR is acquired by radar.
2. The method of claim 1, wherein the RCS measurements are performed on the satellite based on measurement signals comprising a combination of at least frequency and polarization and measurement attitude, the measurement attitude being sampled over a range of calibration angles available from the radar reflector load, the attitude angles including azimuth and elevation dimensions.
3. The method of claim 1, wherein the K value is averaged using the following equation (2):
Figure FSB0000192543770000014
wherein i represents the ith sample, and when i is more than 100, the arithmetic mean value is taken as the final result.
4. The method of claim 1, wherein the satellite platform has a symmetrical, regular shape.
5. An apparatus for radar cross section RCS calibration, comprising:
radar reflector loads having a regular geometric shape;
a satellite platform for carrying the radar reflector load and forming a non-perfect regular shape when the radar reflector load is carried on the satellite platform,
wherein the radar reflector load is configured to receive impinging electromagnetic waves from a ground radar to assist in calibrating the RCS measurement K value,
the calibration comprises the steps of calibrating an RCS measurement K value by utilizing a radar equation and combining an RCS two-dimensional data table obtained by performing RCS measurement on a satellite;
wherein the K value is calibrated by the following formula (1):
Figure FSB0000192543770000021
Ps: radar echo power;
Pr: radar transmission power:
r: the distance between the radar and the calibration body;
g: gain of the radar antenna;
σ: the reflection section of the whole satellite of the satellite;
Figure FSB0000192543770000022
respectively an azimuth angle and a pitch angle of the satellite under a radar observation coordinate system,
Figure FSB0000192543770000023
the values are obtained from a look-up table, G, PrIs a constant value, PsR is acquired by radar.
6. The apparatus of claim 5, wherein the RCS measurements are performed on the satellite based on measurement signals comprising a combination of at least frequency and polarization and measurement attitude, the measurement attitude being sampled over a range of calibration angles available from the radar reflector payload, the attitude angles including both azimuth and elevation dimensions.
7. The apparatus of claim 5, wherein the K value is averaged using the following equation (2):
Figure FSB0000192543770000024
wherein i represents the ith sample, and when i is more than 100, the arithmetic mean value is taken as the final result.
CN201910455642.3A 2019-05-30 2019-05-30 Method and device for radar scattering cross section RCS calibration Active CN110146859B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910455642.3A CN110146859B (en) 2019-05-30 2019-05-30 Method and device for radar scattering cross section RCS calibration

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910455642.3A CN110146859B (en) 2019-05-30 2019-05-30 Method and device for radar scattering cross section RCS calibration

Publications (2)

Publication Number Publication Date
CN110146859A CN110146859A (en) 2019-08-20
CN110146859B true CN110146859B (en) 2021-07-06

Family

ID=67593714

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910455642.3A Active CN110146859B (en) 2019-05-30 2019-05-30 Method and device for radar scattering cross section RCS calibration

Country Status (1)

Country Link
CN (1) CN110146859B (en)

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013036969A (en) * 2011-08-09 2013-02-21 Keycom Corp Radar cross section (rcs) measurement system
DE102014110079B3 (en) * 2014-07-17 2015-07-09 Deutsches Zentrum für Luft- und Raumfahrt e.V. Method for absolute radiometric calibration of the radar backscatter cross section of radar targets
CN106093892B (en) * 2016-05-23 2018-12-18 中国人民解放军63921部队 Carry out Radar RCS calibration and exterior measuring calibration system simultaneously based on calibration satellite
EP3364212A1 (en) * 2017-02-15 2018-08-22 Deutsches Zentrum für Luft- und Raumfahrt e.V. A method and an apparatus for computer-assisted processing of sar raw data
CN109752696B (en) * 2017-11-06 2020-03-10 中国人民解放军61646部队 RCS correction method for corner reflector in high-resolution synthetic aperture radar satellite image
RU2674432C1 (en) * 2018-02-08 2018-12-10 Акционерное общество "Корпорация космических систем специального назначения "Комета" Radar station with the active phased antenna array calibration method
CN108717181B (en) * 2018-06-27 2022-05-06 成都飞机工业（集团）有限责任公司 Novel outdoor field static RCS preposed linkage calibration test method

Also Published As

Publication number Publication date
CN110146859A (en) 2019-08-20

Similar Documents

Publication Publication Date Title
CN110058204B (en) Satellite-borne antenna beam center calibration method based on directional diagram matching
CN108562882B (en) Geometric cross calibration method and system for satellite-borne SAR (synthetic aperture radar) image
CN108717181B (en) Novel outdoor field static RCS preposed linkage calibration test method
CN108879106B (en) Double-reflector antenna profile real-time adjustment method based on optimal fitting
CN109765437B (en) System and method for calibrating simulated curved surface of full-space phased array antenna
CN112325840B (en) Directional antenna angle rapid calibration method based on celestial body tracking and scanning
CN108181618B (en) Radar calibration method
CN107153179A (en) A kind of radar target RCS and scattering center synchronous detecting method
CN114167365A (en) Method and system for acquiring characteristics of guide rail type outfield target and environment radar
CN110146859B (en) Method and device for radar scattering cross section RCS calibration
KR102258202B1 (en) Apparatus for generating pseudo-sea surface model for image decoding apparatus based on airborn
CN113093127A (en) Vehicle radar angle error test system
CN115865142B (en) Radar antenna beam pointing calibration method, system, device and storage medium
CN108981922B (en) Microwave black body emissivity measuring device and measuring method
CN116593981A (en) Small-angle RCS accurate measurement method for single-shot multi-reception cylindrical wave circumferential sparse array local scanning
CN116819460A (en) Baseline calibration method for radar and communication equipment device
CN115166779A (en) Beidou navigation satellite signal foundation monitoring method and system
CN112068087B (en) Shore-based multi-channel radar aircraft-simulated sea clutter measurement method
CN114910944A (en) Phased array antenna tracking precision measuring method
CN114265025A (en) Automatic lobe test and angle zero value calibration device of broadband phased array system
CN110018460B (en) Far field measurement method for phase difference between whole satellite phases of satellite-borne synthetic aperture radar
CN113341238B (en) Method for measuring antenna directional diagram by utilizing solar radiation
CN116879857B (en) Far-field target and radar central beam alignment method
CN112881990B (en) Doppler radar speed resolving method based on antenna near field test
CN116718988B (en) System and method for measuring radar scattering cross section

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
GR01 Patent grant
GR01 Patent grant