CN110988786A - Array direction finding calibration method - Google Patents
Array direction finding calibration method Download PDFInfo
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- CN110988786A CN110988786A CN201911141795.7A CN201911141795A CN110988786A CN 110988786 A CN110988786 A CN 110988786A CN 201911141795 A CN201911141795 A CN 201911141795A CN 110988786 A CN110988786 A CN 110988786A
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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
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
- G01S3/023—Monitoring or calibrating
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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
- G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
- G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
- G01S3/14—Systems for determining direction or deviation from predetermined direction
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- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
The invention provides an array direction finding calibration method, which is characterized in that a calibration signal source is added on an array direction finding calibration system, and the method is characterized in that a method combining pre-calibration and real-time calibration is adopted, the relative error between channels and the amplitude-phase error before the channels are calculated and utilized, the amplitude-phase error calibration and the direction consistency calibration of array signals are carried out, and then super-resolution DOA estimation is carried out. According to the invention, the auxiliary signal source is added, and a mode of combining pre-calibration and real-time calibration is adopted, so that signal source data is collected for real-time calibration every time of direction finding, the error of the array signal is efficiently calibrated, and the calculation is simple.
Description
Technical Field
The invention relates to the technical field of radio direction finding, in particular to an array direction finding calibration method.
Background
In order to enhance a desired signal, a direction-finding station is often placed at a plurality of different positions to form an array signal for direction finding. The super-resolution array direction finding technology is an important research direction and is widely applied to the military fields of radars, sonars and the like. With the development of national defense science and technology, the future war is the information war of high technology, the super-resolution array direction-finding technology occupies an important position in the electronic war, but array errors are inevitable due to factors such as antenna technology, the environment of the array and the like; the direction finding of the super-resolution array has very strict requirements on the consistency of the array, and the direction finding error can be increased and even failed due to array errors. Therefore, the calibration of the array error is particularly important, the existing calibration methods include an adaptive calibration method and an auxiliary information source calibration method, but the global convergence of the adaptive calibration method is difficult to guarantee, and the auxiliary information source needs to have a precisely known direction, so that the method is not suitable for engineering.
The above problems are worth solving.
Disclosure of Invention
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a method for calibrating direction of array features that a calibration signal source is added to the calibration system of direction finding array, and features that the method combining pre-calibration with real-time calibration is used to calibrate the amplitude and phase errors and direction consistency of array signals, and then super-resolution DOA estimation is performed.
The present invention according to the above aspect is characterized by comprising the steps of:
(1) the number of array element channels of the antenna array is set as M;
(2) pre-calibrating an auxiliary signal source in front of an array element channel;
(3) and calibrating the real-time direction-finding signal source in real time.
Further, the step (2) comprises:
(21) obtaining an amplitude-phase error calibration matrix A by adopting a 0-degree auxiliary signal source methodci：Aci＝(Ac1，Ac2,……，AcM)；
(22) Collecting calibration signal source data: controlling each channel to collect calibration signal source data, wherein the fast beat number is M and is respectively recorded as XJi；
(23) Obtaining the relative error A between channelsJi: normalization, denoted A, was performed with channel 1 as referenceJi＝XJi/XJ1；
(24) Calculating the amplitude-phase error A in front of the channelTi＝Aci/AJi；
(25) A is to beTiIs stored in the system.
Further, the step (3) comprises:
(31) acquiring data of a signal source to be detected: each time of direction finding, each channel is controlled to collect signal data to be direction-found, the fast beat number is M, and the fast beat number is recorded as Xi＝(X1，X2，……，XM)；
(32) Acquiring calibration signal data, i.e. repeating said steps (22) and (23), importing AJiValues as a real-time direction-finding calibration matrix;
(33) and (3) amplitude and phase error calibration: calibrating amplitude-phase error of acquired channel data, i.e. XAi＝Xi/(AJi×ATi)；
(34) Calibrating direction consistency: with reference to channel 1, a direction consistency calibration is performed, i.e. XAS＝XAi/E(XA1)；
(35) Calculating the identity matrix R ═ XASXAS′。
Further, A in the step (21)c1＝1。
Further, A in the step (23)J1＝1。
Further, i is a natural number, and 1 ≦ i ≦ M.
The invention has the following beneficial effects:
by adding the auxiliary signal source, a mode of combining pre-calibration and real-time calibration is adopted, signal source data are collected for real-time calibration during direction finding each time, errors of array signals are efficiently calibrated, array consistency is improved, and therefore accuracy of array direction finding is improved.
Drawings
FIG. 1 is a flow chart of the overall implementation of the present invention.
FIG. 2 is a flow chart of pre-channel calibration in the present invention.
Fig. 3 is a flow chart of the real-time calibration in the present invention.
Detailed Description
The invention provides an array direction finding calibration method, which solves the problems of complex algorithm and inapplicable engineering of the existing array direction finding algorithm, adds a 0-degree auxiliary signal source on the basis of the original direction finding system, and calibrates the channel error and the directional diagram error of an array by adopting a mode of combining pre-calibration and real-time calibration.
As shown in fig. 1 to 3, a method for calibrating an array direction finding adds a calibration signal source to an array direction finding calibration system, and specifically includes the following steps:
(1) the number of array element channels of the antenna array is set as M.
(2) The method for pre-calibrating the auxiliary signal source in front of the array element channel comprises the following steps:
(21) obtaining an amplitude-phase error calibration matrix A by adopting a 0-degree auxiliary signal source methodci：Aci＝(Ac1，Ac2,……，AcM)，
i is a natural number, and 1 ≦ i ≦ M, where A isc1＝1；
(22) Collecting calibration signal source data: controlling each channel to collect calibration signal source data, wherein the fast beat number is M and is respectively recorded as XJiI is a natural number, and 1 ≦ i ≦ M;
(23) obtaining the relative error A between channelsJi: normalization, denoted A, was performed with channel 1 as referenceJi＝XJi/XJ1，
i is a natural number, and 1 ≦ i ≦ M, where A isJ1＝1；
(24) Calculating the amplitude-phase error A in front of the channelTi＝Aci/AJiI is a natural number, and 1 ≦ i ≦ M;
(25) a is to beTiIs stored in the system.
(3) The method for calibrating the real-time direction-finding signal source in real time comprises the following steps:
(31) acquiring data of a signal source to be detected: each time of direction finding, each channel is controlled to collect signal data to be direction-found, the fast beat number is M, and the fast beat number is recorded as Xi＝(X1，X2，……，XM) I is a natural number, and 1 ≦ i ≦ M;
(32) acquiring calibration signal data, i.e. repeating said steps (22) and (23), importing AJiValues as a real-time direction-finding calibration matrix;
(33) and (3) amplitude and phase error calibration: calibrating amplitude-phase error of acquired channel data, i.e. XAi＝Xi/(AJi×ATi)，
i is a natural number, and 1 ≦ i ≦ M;
(34) calibrating direction consistency: with reference to channel 1, a direction consistency calibration is performed, i.e. XAS＝XAi/E(XA1)，
i is a natural number, and 1 ≦ i ≦ M;
(35) calculating the identity matrix R ═ XASXAS′。
(4) A super-resolution DOA estimation is performed.
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention are clearly and completely described through implementation modes by referring to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Claims (7)
1. A method for calibrating direction of array features that a calibration signal source is added to the calibration system of direction finding array, and features that the method combining pre-calibration with real-time calibration is used to calibrate the amplitude-phase error and direction uniformity of array signals, and then super-resolution DOA estimation is performed.
2. An array direction-finding calibration method according to claim 1, characterized by comprising the following steps:
(1) the number of array element channels of the antenna array is set as M;
(2) pre-calibrating an auxiliary signal source in front of an array element channel;
(3) and calibrating the real-time direction-finding signal source in real time.
3. An array direction-finding calibration method according to claim 2, wherein the step (2) comprises:
(21) obtaining an amplitude-phase error calibration matrix A by adopting a 0-degree auxiliary signal source methodci：Aci=(Ac1，Ac2,……，AcM)；
(22) Collecting calibration signal source data: controlling each channel to collect calibration signal source data, wherein the fast beat number is M and is respectively recorded as XJi；
(23) Obtaining the relative error A between channelsJi: normalization, denoted A, was performed with channel 1 as referenceJi=XJi/ XJ1；
(24) Calculating the amplitude-phase error A in front of the channelTi=Aci/ AJi；
(25) A is to beTiIs stored in the system.
4. An array direction-finding calibration method according to claim 2, wherein the step (3) comprises:
(31) acquiring data of a signal source to be detected: each time of direction finding, each channel is controlled to collect signal data to be direction-found, the fast beat number is M, and the fast beat number is recorded as Xi=（X1，X2，……，XM）；
(32) Acquiring calibration signal data, i.e. repeating said steps (22) and (23), importing AJiValues as a real-time direction-finding calibration matrix;
(33) and (3) amplitude and phase error calibration: calibrating amplitude-phase error of acquired channel data, i.e. XAi=Xi/(AJi×ATi)；
(34) Calibrating direction consistency: with reference to channel 1, a direction consistency calibration is performed, i.e. XAS=XAi/E(XA1)；
(35) Calculating identity matrix R = XASXAS´。
5. An array direction-finding calibration method according to claim 3, characterized in that in step (21), Ac1=1。
6. An array direction-finding calibration method according to claim 3, characterized in that in the step (23), AJ1=1。
7. The method of claim 3 or 4, wherein i is a natural number and 1 ≦ i ≦ M.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113746571A (en) * | 2021-08-25 | 2021-12-03 | 成都飞机工业（集团）有限责任公司 | Calibration and direction finding inspection method for aerial carrier antenna array |
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Cited By (2)
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| CN113746571A (en) * | 2021-08-25 | 2021-12-03 | 成都飞机工业（集团）有限责任公司 | Calibration and direction finding inspection method for aerial carrier antenna array |
| CN113746571B (en) * | 2021-08-25 | 2022-05-10 | 成都飞机工业（集团）有限责任公司 | Calibration and direction finding inspection method for aerial carrier antenna array |
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