CN116087630A - Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device - Google Patents

Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device Download PDF

Info

Publication number
CN116087630A
CN116087630A CN202211706827.5A CN202211706827A CN116087630A CN 116087630 A CN116087630 A CN 116087630A CN 202211706827 A CN202211706827 A CN 202211706827A CN 116087630 A CN116087630 A CN 116087630A
Authority
CN
China
Prior art keywords
electromagnetic
parameter
point
cross
parameters
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.)
Pending
Application number
CN202211706827.5A
Other languages
Chinese (zh)
Inventor
刘昕
王海文
吴春雷
孙胜
高会泉
李艳茹
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.)
China University of Petroleum East China
Original Assignee
China University of Petroleum East China
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 China University of Petroleum East China filed Critical China University of Petroleum East China
Priority to CN202211706827.5A priority Critical patent/CN116087630A/en
Publication of CN116087630A publication Critical patent/CN116087630A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
    • G01R29/08—Measuring electromagnetic field characteristics
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/10—Geometric CAD
    • G06F30/18—Network design, e.g. design based on topological or interconnect aspects of utility systems, piping, heating ventilation air conditioning [HVAC] or cabling
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/20—Design optimisation, verification or simulation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00—Arrangements for image or video recognition or understanding
    • G06V10/20—Image preprocessing
    • G06V10/26—Segmentation of patterns in the image field; Cutting or merging of image elements to establish the pattern region, e.g. clustering-based techniques; Detection of occlusion
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00—Arrangements for image or video recognition or understanding
    • G06V10/40—Extraction of image or video features
    • G06V10/44—Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V20/00—Scenes; Scene-specific elements
    • G06V20/10—Terrestrial scenes
    • G06V20/176—Urban or other man-made structures
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
    • Y02A90/30—Assessment of water resources

Abstract

The embodiment of the invention provides a multi-point electromagnetic parameter measurement method for cross-modal data. According to the multi-point electromagnetic parameter measurement method for cross-modal data, point cloud data reconstructed by multi-view oblique photographic images are utilized, point positions are marked based on three-dimensional coordinates of the point cloud, optimal arrangement of transmitting points and receiving points for large-range electromagnetic parameter measurement of urban environments is achieved, initial electromagnetic parameters are measured based on a free space method, abnormal initial electromagnetic parameters are detected by utilizing an isolated forest algorithm, abnormal reasons are judged based on image segmentation results, the initial electromagnetic parameters are calibrated, and accurate correction of multi-medium electromagnetic parameters for cross-modal data fusion is achieved. The embodiment of the invention also provides a multi-point electromagnetic parameter measuring device facing the cross-mode data.

Description

Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device
Technical Field
The invention relates to a multi-point electromagnetic parameter measurement method and device, in particular to a multi-point electromagnetic parameter measurement method and device for cross-modal data.
Background
The electromagnetic medium is densely distributed in various facilities in urban environment, the problems of shadow shielding or mixed distribution among ground objects can exist, large errors can exist in electromagnetic parameter measurement based on the open environment of the instrument, and the modeling requirement of the fine electromagnetic medium is difficult to support. Dielectric constant is used as a core parameter for measuring electromagnetic properties of materials, and related researches are always important in the field of electromagnetic parameter measurement.
At present, in the aspect of electromagnetic parameter measurement research, there are two main modes:
1) Transmission/reflection method
The method is based on a scattering network theory, a medium is placed in a coaxial line or a rectangular waveguide, the position of a medium sample is irrelevant to the position of the medium sample in the coaxial line or the rectangular waveguide, a vector network analyzer is used for extracting scattering parameters of a sample area, and then the dielectric constant of the medium is inverted through a scattering equation.
2) Resonant cavity method
The method is characterized in that a measured material is placed at the position of the maximum electric field of a magnetic field in a resonant cavity, when a film-shaped or rod-shaped measured material is placed in a closed or open cavity, the intrinsic quality factor, the intrinsic resonance rate and the field distribution of the material in the cavity are changed, and the electromagnetic parameters are calculated through the change of the quality factor and the resonance frequency parameters before and after the material is placed in the cavity.
The problem with method 1) is that the position, thickness and sampler length of the sample can lead to measurement errors, if the thickness of the sample to be measured is greater than the corresponding waveguide wavelength, there are solutions of multiple propagation constants, and measuring an extremely thin sample to be measured can increase measurement uncertainty. This method can only make measurements indoors.
The method 2) has the problems that the method belongs to the lossy measurement, is mainly suitable for measuring equivalent electrical parameters of dielectric materials which need to be precisely processed, such as films and sheet media, has higher requirements on the preparation of the materials, and has higher requirements on the resolution of measuring instruments such as a frequency meter, a vector network analyzer and the like.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a multi-point electromagnetic parameter measurement method for cross-modal data, which utilizes point cloud data reconstructed by multi-view oblique photographic images to realize the optimal arrangement of transmitting points and receiving points for large-range electromagnetic parameter measurement of urban environments, measures initial electromagnetic parameters based on a free space method and assigns values on the point cloud, utilizes an isolated forest algorithm to detect abnormal initial electromagnetic parameters, judges abnormal reasons based on image segmentation results, calibrates the initial electromagnetic parameters, and realizes the accurate correction of multi-medium electromagnetic parameters for cross-modal data fusion.
The technical scheme adopted by the invention is as follows:
a multi-point electromagnetic parameter measurement method facing to cross-mode data comprises the following components:
A. and designing an electromagnetic signal measuring instrument deployment scheme based on the point cloud data. The method comprises the steps of marking measurement points in advance on point cloud data, utilizing coordinate data of the points, placing electromagnetic signal transmitting antennas on one side of a building along a road at intervals according to a fixed distance, placing a plurality of transmitting antennas on a single building if the building is dense, and placing the same number of receiving antennas on the other side of the building. All the marked points of the transmitting antenna and the receiving antenna are required to be covered, and each point is required to measure data for many times.
B. Initial electromagnetic parameters are measured based on a free space method and assigned on a point cloud. Obtaining a reflection parameter by using the ratio of the coupling signal to the reference signal, obtaining a transmission parameter by using the ratio of the coupling signal to the reference signal, setting a measured network as a dual-port network, calculating an initial electromagnetic parameter of the medium by measuring the reflection parameter and the transmission parameter of the electromagnetic medium, and assigning the initial electromagnetic parameter to a point position corresponding to the point cloud according to the point position marked by the measurement deployment scheme.
C. Detecting an abnormal initial electromagnetic parameter. Based on an isolated forest algorithm, the anomaly scores of the multi-point initial electromagnetic parameters of different measurement mediums are calculated respectively, and the electromagnetic parameters with the anomaly scores close to 1 are used as anomaly points.
D. And judging the abnormal reason by using the image segmentation result and calibrating. And according to the point position coordinates of the abnormal electromagnetic parameters, acquiring the mapping position of the point in the oblique photographic image, judging that the abnormal electromagnetic parameters cause interference due to measurement errors or shielding of different electromagnetic mediums according to the electromagnetic medium type segmentation result of the oblique photographic image, correcting the abnormal electromagnetic parameters by using the median value of the measured values of other points of the measurement medium, and adjusting the positions of the receiving and transmitting antennas and re-measuring the electromagnetic parameters of the point positions.
In step a, the point cloud data refers to: based on three-dimensional point cloud data of the urban ground object reconstructed by the multi-view oblique photography image, point positions in the point cloud comprise three-dimensional coordinate information of a medium to be measured.
In step B, the free space method refers to: electromagnetic waves are radiated into free space by utilizing a focusing lens antenna, a stable quasi-TEM beam is formed near the focal plane of the antenna, the beam is vertically incident on the surface of a sample, and the electromagnetic waves are reflected and transmitted for multiple times at the interface between the medium and the air based on the discontinuity at the surface of the medium. The reflected signal is received by the transmitting antenna, sent to the 1 port of the vector network analyzer, and the transmitted signal is received by the receiving antenna, sent to the 2 port of the vector network analyzer, and the reflected parameter and the transmitted parameter are obtained.
In step D, the electromagnetic medium type segmentation result refers to: the contours of different urban ground features are characterized based on an image segmentation technology to distinguish different electromagnetic mediums.
On the other hand, the invention provides a multi-point electromagnetic parameter measuring device facing to cross-mode data, which comprises the following modules:
an initial electromagnetic parameter calculation module: and calculating a reflection parameter based on the ratio of the coupling signal to the reference signal, obtaining a transmission parameter by using the ratio of the transmission signal to the reference signal, and calculating the initial electromagnetic parameter of the medium based on the reflection parameter and the transmission parameter.
A cross-modal electromagnetic parameter calibration module: detecting initial electromagnetic parameter abnormal points of different measured objects based on an isolated forest algorithm, acquiring the mapping position of the points in the oblique photographic image according to the abnormal electromagnetic parameter point position coordinates, and distinguishing parameter abnormality reasons according to the electromagnetic medium type segmentation result of the oblique photographic image.
The technical scheme and the measuring device provided by the invention have the beneficial effects that:
in the above components, based on three-dimensional point cloud data of urban ground features, transmitting and receiving antennas of a large-scale electromagnetic parameter measurement scheme are optimally arranged, initial electromagnetic parameters are measured by a free space method and assigned on the point cloud, abnormal initial electromagnetic parameters are detected based on an isolated forest algorithm, and the initial electromagnetic parameters are calibrated on the basis of judging electromagnetic parameter abnormality reasons by an image segmentation result, so that accurate correction of multi-medium electromagnetic parameters of cross-modal data fusion is realized.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic flow chart of a multi-point electromagnetic parameter measurement method for cross-modal data.
Fig. 2 is a schematic diagram of an initial electromagnetic parameter measurement deployment scenario disclosed herein.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the embodiments of the present invention will be described in further detail with reference to the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.
Embodiment one:
and defining the range of the area to be measured, and reconstructing three-dimensional point cloud data of the urban ground object by utilizing the multi-view oblique photographic image of the unmanned aerial vehicle. The method comprises the steps of marking measurement points in advance on three-dimensional point cloud data, utilizing coordinate data of the points, placing electromagnetic signal transmitting antennas on one side of a building along a road at intervals according to fixed distances, placing a plurality of transmitting antennas on a single building if the building is dense, and placing the same number of receiving antennas on the other side of the building. The transmitting antenna and the receiving antenna are placed to cover all the marking points.
According to the marked point positions in the measurement deployment scheme, a vector network analyzer, a transmitting antenna and a receiving antenna are arranged, quasi-TEM wave beams are transmitted to a medium to be measured, reflection and transmission signals are received, reflection parameters are obtained through the ratio of coupling signals to reference signals, transmission parameters are obtained through the ratio of coupling signals to the reference signals, the measured network is set to be a dual-port network, initial electromagnetic parameters of the medium are calculated through measuring the reflection parameters and the transmission parameters of the electromagnetic medium, and the initial electromagnetic parameters are assigned to the point positions corresponding to the point cloud.
And calculating the abnormal scores of the initial electromagnetic parameters of the multiple points of each measuring medium by using an isolated forest algorithm, and taking the electromagnetic parameters with the abnormal scores close to 1 as abnormal points. According to the point position coordinates of the abnormal electromagnetic parameters, the mapping position of the point in the oblique photographic image is obtained, according to the electromagnetic medium type segmentation result of the oblique photographic image, whether the abnormal electromagnetic parameters are measurement errors or interference caused by shielding of different electromagnetic mediums is judged, as for the abnormal electromagnetic parameters, the median value of the measured values of other points of the measurement medium can be utilized for correction, as for the abnormal electromagnetic parameters, the positions of the receiving and transmitting antennas are adjusted, the electromagnetic parameters of the point are measured again, and based on cross-modal fusion of image data and instrument measurement data, the accurate correction of the electromagnetic parameters is realized.
In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Claims (5)

1. A multi-point electromagnetic parameter measurement method facing to cross-mode data comprises the following components:
A. and designing an electromagnetic signal measuring instrument deployment scheme based on the point cloud data. The method comprises the steps of marking measurement points in advance on point cloud data, utilizing coordinate data of the points, placing electromagnetic signal transmitting antennas on one side of a building along a road at intervals according to a fixed distance, placing a plurality of transmitting antennas on a single building if the building is dense, and placing the same number of receiving antennas on the other side of the building. All the marked points of the transmitting antenna and the receiving antenna are required to be covered, and each point is required to measure data for many times.
B. Initial electromagnetic parameters are measured based on a free space method and assigned on a point cloud. Obtaining a reflection parameter by using the ratio of the coupling signal to the reference signal, obtaining a transmission parameter by using the ratio of the coupling signal to the reference signal, setting a measured network as a dual-port network, calculating an initial electromagnetic parameter of the medium by measuring the reflection parameter and the transmission parameter of the electromagnetic medium, and assigning the initial electromagnetic parameter to a point position corresponding to the point cloud according to the point position marked by the measurement deployment scheme.
C. Detecting an abnormal initial electromagnetic parameter. Based on an isolated forest algorithm, the anomaly scores of the multi-point initial electromagnetic parameters of different measurement mediums are calculated respectively, and the electromagnetic parameters with the anomaly scores close to 1 are used as anomaly points.
D. And judging the abnormal reason by using the image segmentation result and calibrating. And according to the point position coordinates of the abnormal electromagnetic parameters, acquiring the mapping position of the point in the oblique photographic image, judging that the abnormal electromagnetic parameters cause interference due to measurement errors or shielding of different electromagnetic mediums according to the electromagnetic medium type segmentation result of the oblique photographic image, correcting the abnormal electromagnetic parameters by using the median value of the measured values of other points of the measurement medium, and adjusting the positions of the receiving and transmitting antennas and re-measuring the electromagnetic parameters of the point positions.
2. The method for measuring multi-point electromagnetic parameters for cross-modal data according to claim 1, wherein in the step a, the point cloud data means: based on three-dimensional point cloud data of the urban ground object reconstructed by the multi-view oblique photography image, point positions in the point cloud comprise three-dimensional coordinate information of a medium to be measured.
3. The method for measuring multi-point electromagnetic parameters for cross-modal data according to claim 1, wherein in the step B, the free space method means: electromagnetic waves are radiated into free space by utilizing a focusing lens antenna, a stable quasi-TEM beam is formed near the focal plane of the antenna, the beam is vertically incident on the surface of a sample, and the electromagnetic waves are reflected and transmitted for multiple times at the interface between the medium and the air based on the discontinuity at the surface of the medium. The reflected signal is received by the transmitting antenna, sent to the 1 port of the vector network analyzer, and the transmitted signal is received by the receiving antenna, sent to the 2 port of the vector network analyzer, and the reflected parameter and the transmitted parameter are obtained.
4. The multi-point electromagnetic parameter measurement method for cross-modal data according to claim 1, wherein in the step D, the electromagnetic medium type segmentation result is: the contours of different urban ground features are characterized based on an image segmentation technology to distinguish different electromagnetic mediums.
5. Cross-modal data-oriented multi-point electromagnetic parameter measurement device comprises the following modules:
an initial electromagnetic parameter calculation module: and calculating a reflection parameter based on the ratio of the coupling signal to the reference signal, obtaining a transmission parameter by using the ratio of the transmission signal to the reference signal, and calculating the initial electromagnetic parameter of the medium based on the reflection parameter and the transmission parameter.
A cross-modal electromagnetic parameter calibration module: detecting initial electromagnetic parameter abnormal points of different measured objects based on an isolated forest algorithm, acquiring the mapping position of the points in the oblique photographic image according to the abnormal electromagnetic parameter point position coordinates, and distinguishing parameter abnormality reasons according to the electromagnetic medium type segmentation result of the oblique photographic image.
CN202211706827.5A 2022-12-27 2022-12-27 Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device Pending CN116087630A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211706827.5A CN116087630A (en) 2022-12-27 2022-12-27 Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211706827.5A CN116087630A (en) 2022-12-27 2022-12-27 Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device

Publications (1)

Publication Number Publication Date
CN116087630A true CN116087630A (en) 2023-05-09

Family

ID=86186248

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211706827.5A Pending CN116087630A (en) 2022-12-27 2022-12-27 Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device

Country Status (1)

Country Link
CN (1) CN116087630A (en)

Similar Documents

Publication Publication Date Title
CN107505603B (en) Method and apparatus for testing the emission and reflection properties of a radome for a vehicle
CN108037374B (en) Array antenna near field calibration method
CN109669075B (en) Dielectric complex dielectric constant nondestructive reflection measurement method based on open rectangular waveguide
CN109557043B (en) System and method for detecting electromagnetic characteristics of object by using terahertz electromagnetic wave
CN110780124B (en) High-temperature environment terahertz material dielectric property measuring device and method
Eser et al. Open-area test site (OATS) calibration
US6657596B2 (en) Method of measuring a pattern of electromagnetic radiation
RU2308050C1 (en) Method for measurement of effective dispersion area of ground objects by radar with synthesized antenna aperture
Brancaccio et al. A free-space method for microwave characterization of materials in aerospace application
CN116087630A (en) Cross-modal data-oriented multi-point electromagnetic parameter measurement method and device
Fordham An introduction to antenna test ranges, measurements and instrumentation
Chen et al. Examination of Antenna Calibration Methodologies in an Extrapolation Range
EP4214801B1 (en) Radome measurement
CN112034406B (en) Phase calibration method for portable electrical thickness tester
Shi et al. A new permittivity measurement method for walls in indoor scenes
CN109580661B (en) Method for testing complex reflection coefficient of free space material
CN114487618A (en) Composite material low-frequency electromagnetic parameter equivalent extraction device and method
CN114527439A (en) Method for calculating target radar scattering cross section based on complex impedance
CN113777411B (en) Terahertz wave band material complex dielectric constant measuring method and device
Jansen et al. Scaled radar cross section measurements with terahertz-spectroscopy up to 800 GHz
CN113109771A (en) Calibration device for calibrator and weather radar echo intensity true value calibration method
Iwasaki et al. Systematic uncertainties of the complex antenna factor of a dipole antenna as determined by two methods
Fuerholz et al. Phase-corrected near-field measurements of the TELIS telescope at 637 GHz
CN113670433B (en) Method capable of improving on-line sensitivity measurement accuracy of array elements of hydrophone array
KR100443551B1 (en) System of emi measurement using data obtained at free space

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