CN114636861A - Metamaterial low-frequency insertion loss testing method and device - Google Patents
Metamaterial low-frequency insertion loss testing method and device Download PDFInfo
- Publication number
- CN114636861A CN114636861A CN202210175216.6A CN202210175216A CN114636861A CN 114636861 A CN114636861 A CN 114636861A CN 202210175216 A CN202210175216 A CN 202210175216A CN 114636861 A CN114636861 A CN 114636861A
- Authority
- CN
- China
- Prior art keywords
- metamaterial
- insertion loss
- frequency
- low
- antenna
- 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
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2688—Measuring quality factor or dielectric loss, e.g. loss angle, or power factor
- G01R27/2694—Measuring dielectric loss, e.g. loss angle, loss factor or power factor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/16—Spectrum analysis; Fourier analysis
-
- 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
- G01R29/10—Radiation diagrams of antennas
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Mathematical Physics (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Abstract
The invention discloses a method and a device for testing low-frequency insertion loss of a metamaterial, wherein the method comprises the following steps of: utilizing an antenna to send out a low-frequency electromagnetic signal, and measuring the far-field intensity distribution sent out by the antenna at a target point; placing the metamaterial between the antenna and the target point, and measuring the far field intensity distribution emitted by the antenna at the target point again; and (3) subtracting the field intensity data of the same antenna frequency and the same target point under the two conditions of the presence or absence of the metamaterial to obtain relative field intensity change, namely the insertion loss. The invention measures the far field distribution of the electromagnetic waves after a certain distance under the condition of no metamaterial block, so as to measure the insertion loss of the metamaterial, thereby realizing the accurate measurement of the low-frequency insertion loss of the metamaterial with low cost.
Description
Technical Field
The invention belongs to the field of metamaterial performance index testing, and particularly relates to a metamaterial low-frequency insertion loss testing method and device.
Background
The stealth radome applied to communication antennas such as radars must have the following characteristics: in the working frequency band, the electromagnetic wave is allowed to well penetrate, and in the working frequency band, the broadband wave absorption with high absorptivity is carried out on the incident enemy radar wave. Fig. 2 is a schematic diagram of reflection and transmission coefficients of an ideal wave-absorbing/wave-transmitting integrated material.
As a class of artificial materials with special properties, the metamaterial can change the common properties of electromagnetic waves, so that the metamaterial has wide application prospects in the aspects of high-receiving-rate antennas, radar reflectors and the like.
However, the metamaterial has a limited processing area and is expensive, and the low-frequency electromagnetic wave has a long wavelength, which results in a strong diffraction capability. Therefore, if the method of antenna transmission and reception is directly used, the influence of diffraction on the technical index of the precise measurement of the insertion loss cannot be effectively avoided in a laboratory environment.
The general test method for the insertion loss of the metamaterial is to focus electromagnetic waves emitted by an antenna by using a lens and then carry out normalization under the condition of direct connection; and then measuring the loss of the transmitting and receiving electromagnetic waves under the condition of adding the metamaterial, thereby measuring the insertion loss. This approach can be applied to most scenarios, such as: the electromagnetic wave with higher frequency is focused by the lens, and the diffraction loss and the like are relatively ignored. For electromagnetic waves with lower frequency, such as L-band and S-band electromagnetic waves, the wavelength is increased, the laboratory test distance is limited, and the electromagnetic wave loss caused by diffraction and other conditions cannot be ignored.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a metamaterial low-frequency insertion loss testing method and device, and solves the problem that the metamaterial cannot accurately measure the low-frequency electromagnetic wave insertion loss due to the influence of diffraction.
In order to achieve the aim, the invention provides a metamaterial low-frequency insertion loss testing method, which comprises the following steps of:
utilizing an antenna to send out a low-frequency electromagnetic signal, and measuring the far-field intensity distribution sent out by the antenna at a target point;
placing the metamaterial between the antenna and the target point, and measuring the far field intensity distribution emitted by the antenna at the target point again;
and (3) subtracting the field intensity data of the same antenna frequency and the same target point under the two conditions of the presence or absence of the metamaterial to obtain relative field intensity change, namely the insertion loss.
Further, the relative field intensity change of each scanning position is obtained by using the scanning frame, and the average value of the field intensity change under a certain frequency is obtained by using an integral average method for a group of obtained relative field intensity change values to serve as the final insertion loss.
Further, relative field intensity changes under different frequencies are obtained, a curve is drawn, and a corresponding insertion loss curve is obtained.
Further, the low frequency range is 900MHz-3 GHz.
Furthermore, a signal generator is connected with the transmitting antenna, and the frequency of the signal transmitted by the transmitting antenna is set by the signal generator.
Further, the spectrum analyzer is connected with the scanning frame to obtain far field intensity distribution.
The invention also provides a metamaterial low-frequency insertion loss testing device for realizing the metamaterial low-frequency insertion loss testing method, which comprises a transmitting antenna, a signal generator, a scanning frame and a spectrum analyzer; the signal generator is connected with the transmitting antenna and used for setting the frequency of the signal transmitted by the transmitting antenna; the scanning frame is connected with the spectrum analyzer and is used for measuring the far field intensity distribution emitted by the antenna at the target point.
Further, the device also comprises a movable support used for fixing and moving the transmitting antenna.
Furthermore, the device also comprises a non-magnetic frame used for fixing the metamaterial to be tested.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the invention measures the far field distribution of the electromagnetic waves after a certain distance under the condition of no metamaterial block, so as to measure the insertion loss of the metamaterial, thereby realizing the accurate measurement of the low-frequency insertion loss of the metamaterial with low cost.
Drawings
FIG. 1 is a schematic diagram of a metamaterial low-frequency insertion loss testing device according to the present invention;
fig. 2 is a schematic diagram of reflection and transmission coefficients of an ideal wave-absorbing/wave-transmitting integrated material.
In the figure: 1-transmitting antenna, 2-scanning frame, 3-antenna housing, 4-signal generator, 5-spectrum analyzer and 6-mobile support.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The invention aims to solve the problem that the insertion loss of electromagnetic waves in L and S wave bands cannot be accurately measured due to the influence of diffraction on a metamaterial with a limited area. The insertion loss of the metamaterial is accurately calculated by measuring the difference value of the field distribution, so that the core point of the metamaterial low-frequency insertion loss test method is based on the field distribution.
The general test method for the insertion loss of the metamaterial is to focus electromagnetic waves emitted by an antenna by using a lens and then carry out normalization under the condition of direct connection; and then measuring the loss of the transmitting and receiving electromagnetic waves under the condition of adding the metamaterial, thereby measuring the insertion loss. The method can be suitable for most scenes, such as electromagnetic waves with high frequency, and after the electromagnetic waves are focused by the lens, the loss of diffraction and the like is relatively ignored. For electromagnetic waves with lower frequency, such as L-band and S-band electromagnetic waves, the electromagnetic wave loss caused by diffraction and other conditions cannot be ignored due to the fact that the wavelength is increased and the laboratory test distance is limited. Therefore, the insertion loss of the metamaterial is measured by measuring the far field distribution of the electromagnetic waves after a certain distance under the condition of whether the metamaterial blocks the electromagnetic waves or not. Based on the design idea, the problem of accurate measurement of the short-distance insertion loss of the low-frequency electromagnetic wave at present is solved.
As shown in fig. 1, the present embodiment is described by taking an S-band transparent integrated radome performance test as an example:
s1: preparing one transmitting antenna 1 of 900MHz-3GHz, one pair of focusing lenses on the transmitting antenna 1, one electromagnetic field scanning frame 2, one signal generator 4, one frequency spectrum analyzer 5 and one nonmagnetic antenna housing frame, and fixing the metamaterial to be tested, namely the S-waveband absorbing and transmitting integrated antenna housing.
S2: the instruments are put completely in sequence and connected by using a coaxial cable. Transmitting antenna 1 is connected with signal generator 4, and electromagnetic field scan rack 2 is connected with spectral analysis appearance 5, and transmitting antenna 1 and scan rack 2 collinear and 3 meters apart from, do not have magnetism radome frame and put in collinear and 2 meters apart from the antenna.
S3: the signal generator 4 is set to emit a 900MHz signal from the antenna, the scanning frame 2 and the spectrum analyzer 5 are set, and the far field intensity distribution emitted from the antenna at a distance of 3 m is measured and recorded without placing the radome 3.
S4: under the condition of step S3, the metamaterial antenna housing 3 is placed in a nonmagnetic frame, and the far field intensity distribution emitted by the antenna at a distance of 3 meters is measured again and recorded.
S5: the signal generator 4 is set to step to 100MHz, and the steps S3 and S4 are repeated ten times to cover the frequency range of 900MHz-2 GHz.
S6: and (3) carrying out subtraction on the data of the field intensity of the same position under the conditions of the same antenna frequency and the presence or absence of the metamaterial to obtain the relative field intensity change of each position. And obtaining the average value of the field intensity change under a certain frequency by using an integral calculation method for the obtained group of field intensity change values.
S7: from the data recorded in step S5, the average value of the field strength variation at different frequencies is obtained. And drawing a curve to obtain a corresponding insertion loss curve.
The invention reasonably designs the steps and instruments of the experimental method for the first time aiming at the diffraction condition of low-frequency electromagnetic waves and the electromagnetic theory, and realizes the accurate measurement of the low-frequency insertion loss of the metamaterial with short distance and low cost. The test method uses an integral average method, provides a new measurement idea for the short-distance insertion loss accurate measurement of the low-frequency electromagnetic wave, and is also suitable for the measurement of the high-frequency insertion loss.
In conclusion, the antenna with the focusing lens is used for focusing the electromagnetic waves of the L waveband and the S waveband, then the scanning frame is used for measuring the far field distribution of the emitted electromagnetic waves, and the insertion loss of the metamaterial is accurately calculated according to the difference value of the field distribution under the condition that the metamaterial antenna housing exists or not, so that the accurate measurement of the low-frequency insertion loss of the metamaterial in a short distance and at low cost is realized in a laboratory environment.
It will be understood by those skilled in the art that the foregoing is merely a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included within the scope of the present invention.
Claims (9)
1. A metamaterial low-frequency insertion loss testing method is characterized by comprising the following steps:
utilizing an antenna to send out a low-frequency electromagnetic signal, and measuring the far-field intensity distribution sent out by the antenna at a target point;
placing the metamaterial between the antenna and the target point, and measuring the far field intensity distribution emitted by the antenna at the target point again;
and (3) subtracting the field intensity data of the same antenna frequency and the same target point under the two conditions of the presence or absence of the metamaterial to obtain the relative field intensity change, namely the insertion loss.
2. The metamaterial low-frequency insertion loss testing method as claimed in claim 1, wherein a relative field strength change of each scanning position is obtained by using a scanning frame, and an average value of field strength changes at a certain frequency is obtained by using an integral average method for a group of obtained relative field strength change values to serve as a final insertion loss.
3. The metamaterial low-frequency insertion loss test method as claimed in claim 1, wherein relative field strength changes at different frequencies are obtained, and a curve is drawn to obtain a corresponding insertion loss curve.
4. The metamaterial low-frequency insertion loss test method as claimed in claim 1, wherein the low frequency range is 900MHz-3 GHz.
5. The method for testing the low-frequency insertion loss of the metamaterial according to claim 1, wherein a signal generator is connected with the transmitting antenna, and the frequency of the signal transmitted by the transmitting antenna is set by the signal generator.
6. The metamaterial low-frequency insertion loss test method as claimed in claim 1, wherein a spectrum analyzer is connected with the scanning frame to obtain far-field intensity distribution.
7. A metamaterial low-frequency insertion loss test device for realizing the metamaterial low-frequency insertion loss test method as claimed in any one of claims 1 to 6, which is characterized by comprising a transmitting antenna, a signal generator, a scanning frame and a spectrum analyzer; the signal generator is connected with the transmitting antenna and used for setting the frequency of the signal transmitted by the transmitting antenna; the scanning frame is connected with the spectrum analyzer and is used for measuring the far field intensity distribution emitted by the antenna at the target point.
8. The metamaterial low frequency insertion loss test device as in claim 7, further comprising a moving bracket for fixing and moving the transmitting antenna.
9. The metamaterial low-frequency insertion loss testing device as claimed in claim 7, wherein the device further comprises a nonmagnetic frame for fixing the metamaterial to be tested.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210175216.6A CN114636861A (en) | 2022-02-25 | 2022-02-25 | Metamaterial low-frequency insertion loss testing method and device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210175216.6A CN114636861A (en) | 2022-02-25 | 2022-02-25 | Metamaterial low-frequency insertion loss testing method and device |
Publications (1)
Publication Number | Publication Date |
---|---|
CN114636861A true CN114636861A (en) | 2022-06-17 |
Family
ID=81948648
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210175216.6A Pending CN114636861A (en) | 2022-02-25 | 2022-02-25 | Metamaterial low-frequency insertion loss testing method and device |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114636861A (en) |
-
2022
- 2022-02-25 CN CN202210175216.6A patent/CN114636861A/en active Pending
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2019214570A1 (en) | Method, apparatus and system for measuring total radiated power of array antenna | |
CN110401500B (en) | Measuring device and measuring method | |
US11791564B2 (en) | Near-field antenna for remote radio control of an antenna array | |
CN102857310A (en) | Test method and device for wireless indexes of active antenna system | |
JP7329085B2 (en) | High-speed OTA production line test platform | |
US11372037B2 (en) | Freespace antenna measurement system | |
CN112558001B (en) | Pulse high-power field calibration device and method | |
CN113242098B (en) | Radio frequency performance test system and method | |
CN112834830A (en) | Antenna near-field coupling measurement device and method | |
CN109884606A (en) | Based on single antenna radar cross section rcs measurement device and method for analyzing performance | |
JP2022078723A (en) | Dielectric constant measuring device, dielectric constant measuring method, program, and storage medium | |
CN117590092A (en) | Antenna radiation efficiency measuring method and system and electronic equipment | |
CN114636861A (en) | Metamaterial low-frequency insertion loss testing method and device | |
CN113435023B (en) | Method for measuring characteristics of high-frequency band dielectric material | |
CN214375029U (en) | Compact range antenna test system | |
CN108896965A (en) | 200GHz frequency band signals receive and dispatch measuring system | |
Zhang et al. | In situ measurement of absorbing properties of materials based on near-field reflection method | |
Räisänen et al. | Measurements of high-gain antennas at THz frequencies | |
US10996252B2 (en) | Measurement arrangement and measurement method | |
JPH06160449A (en) | Instrument for measuring influence of object on electromagnetic field | |
Mandaris | High strength electromagnetic field generation for radiated EMI measurements | |
Tatsuta et al. | Development of 2D near field scanner for electromagnetic noise visualization | |
CN221174807U (en) | Radome dielectric property test system | |
Hozen et al. | An Experimental Study on DOA/DOD Measurement Method at 300 GHz Band by Double-Directional Rotating Reflector Antenna | |
Al Neyadi et al. | Improvement of Radiated Emission Measurement Chain by Utilizing a Metallic Planar Lens |
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 |