CN110829033B - High-efficiency electromagnetic wave frequency conversion time domain super surface - Google Patents
High-efficiency electromagnetic wave frequency conversion time domain super surface Download PDFInfo
- Publication number
- CN110829033B CN110829033B CN201911030353.5A CN201911030353A CN110829033B CN 110829033 B CN110829033 B CN 110829033B CN 201911030353 A CN201911030353 A CN 201911030353A CN 110829033 B CN110829033 B CN 110829033B
- Authority
- CN
- China
- Prior art keywords
- electromagnetic wave
- time domain
- frequency conversion
- frequency
- super surface
- 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
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
- H01Q15/0086—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
Abstract
The invention discloses a high-efficiency electromagnetic wave frequency conversion time domain super surface, which comprises: the n basic units are arranged periodically and controlled by the signal generated by the same control circuit. The invention has the beneficial effects that: (1) the invention has simple principle, and can realize the frequency conversion of the electromagnetic waves only by changing the frequency and the waveform of the control signal; (2) the invention uses a plurality of basic units to form an array, and is controlled by the same signal, thereby reducing the interference to the unit reflection coefficient caused by different boundaries, and simultaneously reducing the design complexity of a feed network; (3) compared with the traditional design, the basic unit of the invention has the characteristics of large phase shift range, low transmission loss and the like, thereby having ultrahigh conversion efficiency and excellent interference harmonic suppression capability.
Description
Technical Field
The invention relates to the technical field of artificial electromagnetic materials, in particular to a high-efficiency electromagnetic wave frequency conversion time domain super surface.
Background
The novel artificial electromagnetic surface, also known as a super surface, can control the parameters of amplitude, phase, polarization, wave beam, orbital angular momentum and the like of electromagnetic waves by designing the unit characteristics and spatial arrangement of the surface, realizes the functions of deflection, focusing, wave absorption and the like of electromagnetic energy, and can be used in the fields of antennas, imaging and the like. By introducing an adjustable technology, an adjustable super surface capable of controlling various parameters of electromagnetic waves in real time can be designed. The control signal of the traditional adjustable super surface is static or is changed at a very low frequency, so that the adjustable super surface is a linear device and can only adjust and control some linear characteristics of electromagnetic waves, such as amplitude, phase, polarization and the like.
Disclosure of Invention
The invention aims to provide a high-efficiency electromagnetic wave frequency conversion time domain super surface which can efficiently convert the frequency of an electromagnetic wave in a free space.
To solve the above technical problem, the present invention provides a high efficiency electromagnetic wave frequency conversion time domain super surface, comprising: the n basic units are arranged periodically and controlled by the signal generated by the same control circuit.
Preferably, the basic unit comprises a top layer structure, a dielectric substrate and a bottom layer structure; the top layer structure comprises metal patterns, a variable capacitance diode, a patch capacitor and a feed grid, wherein the variable capacitance diode and the patch capacitor are respectively bridged between different metal patterns, and the feed grid is connected to one side of the metal patterns and used for loading control signals to two ends of the variable capacitance diode; the bottom layer structure comprises a metal back plate; the three-layer structure is connected through a plurality of rows of metal through holes.
Preferably, the analog voltage generated by the control circuit is loaded to two ends of a varactor on the basic unit through a feed network, so as to change the equivalent capacitance of the varactor, and further change the electromagnetic characteristics of the unit, specifically, at a specified frequency point, the backward reflection phase of the electromagnetic wave changes by more than 2.5 pi, and the reflection amplitude fluctuation is less than 3.5 dB.
Preferably, when the time domain super surface is irradiated by the electromagnetic wave, the reflection characteristic of the time domain super surface is dynamically changed at a high speed, so that the electromagnetic wave generates a new frequency component, and a control waveform which enables the reflection phase of the super surface to be continuously and linearly changed is designed by measuring the mapping relation between the control voltage and the reflection phase and amplitude of the super surface, so that the energy ratio of the electromagnetic wave at a certain new frequency is greatly improved, and the high-efficiency frequency conversion is realized.
The invention has the beneficial effects that: (1) the invention has simple principle, and can realize the frequency conversion of the electromagnetic waves only by changing the frequency and the waveform of the control signal; (2) the invention uses a plurality of basic units to form an array, and is controlled by the same signal, thereby reducing the interference to the unit reflection coefficient caused by different boundaries, and simultaneously reducing the design complexity of a feed network; (3) compared with the traditional design, the basic unit of the invention has the characteristics of large phase shift range, low transmission loss and the like, thereby having ultrahigh conversion efficiency and excellent interference harmonic suppression capability.
Drawings
FIG. 1 is a schematic diagram of a time domain super surface of the present invention.
FIG. 2 is a schematic diagram of the calculation results of the harmonic waves of each order of the reflected wave under the condition of different slopes p of the time domain super-surface reflection coefficient phase waveform of the present invention.
FIG. 3(a) is a schematic diagram of the basic unit of the time domain super surface of the present invention.
FIG. 3(b) is a schematic diagram of the basic unit of the time domain super surface of the present invention.
FIG. 3(c) is a diagram showing simulation results of the variation of the reflection coefficient amplitude of the time domain super-surface elementary unit with the control voltage.
FIG. 3(d) is a diagram illustrating simulation results of phase variation of reflection coefficients of the time domain super-surface basic unit with control voltage according to the present invention.
FIG. 4(a) is a time domain super-surface object diagram of the present invention.
FIG. 4(b) is a schematic diagram of the results of the amplitude and phase test of the reflection coefficient of the time domain super-surface under different control voltages.
Fig. 4(c) is a schematic diagram of the amplitude normalization result of the measured reflected wave +1 order harmonic when the time domain super surface of the present invention is loaded with control signals corresponding to different slopes p and fixed periods.
FIG. 5 is a diagram illustrating the spectrum distribution of reflected waves in different control signal periods T when the phase change slope p of the reflection coefficient is fixed for the time domain super surface of the present invention.
Detailed Description
As shown in figure 1, the high-efficiency electromagnetic wave frequency conversion time domain super surface is formed by periodically arranging the same basic units, and a plurality of basic units form an array through a feed network, which is similar to a plane reflection array. The reflection coefficient can be regulated and controlled in real time through an external control signal. Therefore, when the super surface is irradiated by the electromagnetic wave, real-time control of each characteristic parameter of the reflected wave can be realized.
The principle of the invention lies in that the phase of the reflection coefficient of the basic unit is changed in a linear cycle with a certain slope by using an external control signal, and the cycle is T. At this time, when the incident electromagnetic wave has a single tone frequency fcDuring the process, the electromagnetic wave reflected by the super surface is changed into a mixing signal with the frequency of the incident wave as the center and the reciprocal of the period of the control signal as the interval of the harmonic frequency. Under the condition of different slopes p, the calculation result of the amplitude-phase distribution of each order of harmonic wave of the reflected wave is shown in fig. 2, and it can be seen from the result that when p is 2k pi/T, only the k-th order harmonic wave will exist in the reflected wave, and the frequency is fc+ k/T, conversion efficiency 100%. According to the principle, the invention can realize the frequency fcIs converted into a frequency fcAnd the electromagnetic wave of + k/T, and the energy utilization efficiency is as high as 100%.
In order to realize high-efficiency electromagnetic wave frequency conversion, the time domain super-surface basic unit is required to have the characteristics of low loss and full phase coverage of reflection coefficient. The basic unit structure designed by the invention is shown in fig. 3(a) and 3(b), and is mainly divided into three layers: upper surface structure, medium base plate and lower surface structure. The upper surface structure consists of a plurality of metal rectangular strips with different thicknesses and a variable capacitance diode/patch capacitor connected in bridge; the intermediate medium substrate is made of F4B and has a thickness of 5 mm; the lower surface structure is a whole metal back plate. In addition, each basic unit also comprises two rows of metal through holes penetrating through the upper surface and the lower surface. By optimizing the period of the basic unit, the size of the metal rectangular strip and the thickness of the medium, the basic unit finally satisfies the low loss characteristic in amplitude and has a large phase variation range in a specified frequency band, and the result is shown in fig. 3(c) and 3 (d): FIG. 3(c) is a graph of simulation results of unit reflection amplitude varying with control voltage; FIG. 3(d) is a graph showing the simulation result of the cell reflection phase varying with the control voltage. From whichIt can be seen that at 4.25GHz, the fundamental cell reflection amplitude fluctuates within 3dB, and the reflection phase varies by more than 2.78 pi. The final optimized basic unit size is: px=24mm,Py=12mm,H=5mm,N=6.9mm,L=5.6mm,g=0.7mm,d=1.2mm,t=1.5mm,Φ=0.4mm。
Fig. 4(a) is a diagram showing a high-efficiency electromagnetic wave frequency conversion time domain super surface object proposed by the present invention, and the diagram further includes a feed horn antenna and a bracket. The invention contains 8 × 16 basic units and can be controlled by the same control signal. In the present invention, the basic cell reflection coefficient needs to be changed by controlling the voltage, and thus the reflection phaseCorresponding to the control voltage V. When incident wave fcThe results of the amplitude and phase test of the reflection coefficient under different control voltages V are shown in fig. 4(b) when the time domain super-surface is normally incident at 4.25GHz, and it can be seen from the results that, in the process of the control voltages from 0V to 21V, the reflection amplitude of the super-surface basic unit fluctuates less than 3.5dB, and the phase varies over 2.5 pi.
From the result of fig. 4(b), the control signal waveform required for linearly changing the phase of the reflection coefficient of the basic unit can be reversely deduced. When the period T of the control signal is 10 μ s, the control signals corresponding to different slopes p are applied to the super-surface, and the amplitude of the +1 th harmonic of the reflected wave is measured, the normalization result is shown in fig. 4(c), and the dotted line in the graph is the simulation calculation result. It can be seen that when the slope p is 2 pi/T, the amplitude of the +1 th harmonic of the reflected wave will reach a maximum of 0.9424, i.e., 88.81% energy conversion efficiency.
FIG. 5 is a diagram showing the spectrum distribution of the reflected wave in different periods T of the control signal when the phase change slope p of the super-surface reflection coefficient is fixed. When the conversion frequency is +1 order harmonic, p is 2 pi/T; when the conversion frequency is-1 order harmonic, p is-2 pi/T. The results of the frequency conversion efficiency and the maximum interference harmonic rejection ratio for different control signal periods T are summarized in table 1. The result shows that the invention not only has high conversion efficiency for the frequency conversion of the electromagnetic wave, but also has excellent interference harmonic suppression capability.
TABLE 1 frequency conversion efficiency and maximum interference harmonic rejection ratio of time domain super surface under different control signal periods T
General results table
The electromagnetic wave frequency conversion by the invention can be divided into four steps:
(1) determining the required switching frequency f1With operating frequency fcDifference δ f ═ f1-fc;
(2) Taking the reciprocal of the frequency difference mode as a control signal period T which is 1/mod (delta f);
(3) when f is1<fcIf so, taking the slope p as-2 pi/T, and otherwise, taking the slope p as 2 pi/T;
(4) and loading a control signal generated by the control circuit to the time domain super surface to complete the frequency conversion of the electromagnetic wave.
According to the invention, the control signal of the super-surface is dynamically changed at a high speed, and an additional degree of freedom is provided in the time dimension, so that the time domain super-surface becomes a nonlinear device on the premise of not using a nonlinear material, and electromagnetic waves can generate new frequency components, thereby realizing high-efficiency electromagnetic wave frequency conversion.
The high-efficiency electromagnetic wave frequency conversion time domain super surface provided by the invention enables the super surface to have a reflection coefficient with linear phase change by utilizing a control signal, and realizes high-efficiency frequency conversion and excellent interference harmonic suppression. The invention has simple principle, low cost and easy realization, which has great application value in the fields of communication, stealth and imaging.
Claims (4)
1. High efficiency electromagnetic wave frequency conversion time domain metasurface, comprising: n basic units are arranged periodically and controlled by signals generated by the same control circuit; phasing the reflection coefficients of the elementary cells by means of an external control signalThe bit is linearly and periodically changed in a form with a certain slope, and the period is T; the process of electromagnetic wave frequency conversion specifically comprises the following steps: first, the required switching frequency f is determined1With operating frequency fcDifference δ f ═ f1-fc(ii) a Secondly, taking the reciprocal of the frequency difference mode as a control signal period T which is 1/mod (delta f); thirdly, when f1<fcIf so, taking the slope p as-2 pi/T, and otherwise, taking the slope p as 2 pi/T; and finally, loading the control signal generated by the control circuit to the time domain super surface to complete the frequency conversion of the electromagnetic wave.
2. A high efficiency electromagnetic wave frequency converted time domain meta-surface as claimed in claim 1 wherein the base unit includes a top layer structure, a dielectric substrate and a bottom layer structure; the top layer structure comprises metal patterns, a variable capacitance diode, a patch capacitor and a feed grid, wherein the variable capacitance diode and the patch capacitor are respectively bridged between different metal patterns, and the feed grid is connected to one side of the metal patterns and used for loading control signals to two ends of the variable capacitance diode; the bottom layer structure comprises a metal back plate; the three-layer structure is connected through a plurality of rows of metal through holes.
3. The high-efficiency electromagnetic wave frequency conversion time domain super surface according to claim 2, wherein the analog voltage generated by the control circuit is loaded to two ends of a varactor diode on the basic unit through a feed network to change the equivalent capacitance thereof, thereby changing the electromagnetic characteristics of the unit, the backward reflection phase of the electromagnetic wave changes by more than 2.5 pi at a designated frequency point, and the reflection amplitude fluctuation is less than 3.5 dB.
4. The high efficiency electromagnetic wave frequency conversion time domain super surface according to claim 3, wherein when the time domain super surface is irradiated by the electromagnetic wave, the reflection characteristic thereof is dynamically changed at a high speed to generate a new frequency component for the electromagnetic wave, and a control waveform for continuously and linearly changing the super surface reflection phase is designed by measuring the mapping relation between the control voltage and the super surface reflection phase and amplitude, thereby greatly increasing the energy ratio at a certain new frequency of the electromagnetic wave and realizing the high efficiency frequency conversion.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911030353.5A CN110829033B (en) | 2019-10-28 | 2019-10-28 | High-efficiency electromagnetic wave frequency conversion time domain super surface |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911030353.5A CN110829033B (en) | 2019-10-28 | 2019-10-28 | High-efficiency electromagnetic wave frequency conversion time domain super surface |
Publications (2)
Publication Number | Publication Date |
---|---|
CN110829033A CN110829033A (en) | 2020-02-21 |
CN110829033B true CN110829033B (en) | 2021-04-27 |
Family
ID=69550894
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201911030353.5A Active CN110829033B (en) | 2019-10-28 | 2019-10-28 | High-efficiency electromagnetic wave frequency conversion time domain super surface |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110829033B (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IL273995A (en) | 2020-04-16 | 2021-10-31 | Univ Ramot | Radar invisibility and cloaking with time-modulated metasurfaces |
EP4173083A1 (en) * | 2020-06-23 | 2023-05-03 | Ariel Scientific Innovations Ltd. | System and method for reconfigurable metasurface sub reflector |
CN113206385B (en) * | 2021-04-09 | 2022-04-19 | 华中科技大学 | Control method and control device for intelligent super-surface structure unit |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105305091A (en) * | 2015-10-13 | 2016-02-03 | 复旦大学 | Tunable gradient meta-surface-based reflection electromagnetic wave modulator and design method thereof |
CN205863402U (en) * | 2016-05-19 | 2017-01-04 | 深圳超级数据链技术有限公司 | Meta Materials |
CN108511916A (en) * | 2018-02-12 | 2018-09-07 | 东南大学 | A kind of Digital Programmable space-time code Meta Materials |
CN108923814A (en) * | 2018-05-29 | 2018-11-30 | 东南大学 | It may be programmed the wireless communications method and system of Meta Materials based on time domain |
CN109067445A (en) * | 2018-09-27 | 2018-12-21 | 东南大学 | A kind of super surface of time domain coding for wireless communication |
CN109935964A (en) * | 2017-12-15 | 2019-06-25 | 华为技术有限公司 | A kind of antenna element and aerial array |
CN109994838A (en) * | 2017-12-29 | 2019-07-09 | 深圳光启尖端技术有限责任公司 | A kind of controllable absorbing meta-material |
CN110365616A (en) * | 2019-06-27 | 2019-10-22 | 东南大学 | Surpass the multi-user wireless communication system and method on surface based on space-time code |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101501927B (en) * | 2006-04-27 | 2013-09-04 | 泰科电子服务有限责任公司 | Antennas, devices and systems based on metamaterial structures |
TWI525902B (en) * | 2012-03-22 | 2016-03-11 | 美國博通公司 | Artificial magnetic mirror cell and applications thereof |
CN104201443B (en) * | 2014-08-14 | 2017-07-11 | 上海师范大学 | A kind of bifrequency Terahertz bandpass filter and preparation method thereof |
US20170235162A1 (en) * | 2015-07-13 | 2017-08-17 | Purdue Research Foundation | Time-varying metasurface structure |
CN104977272B (en) * | 2015-07-17 | 2017-11-07 | 浙江大学 | Terahertz Meta Materials and biological sample method for amplifying signal associated with nanogold particle |
US10498042B2 (en) * | 2015-11-13 | 2019-12-03 | Kyungpook National University Industry-Academic Cooperation Foundation | Reflection frequency conversion device using active metamaterial surface and ECM system |
CN105785601B (en) * | 2016-04-07 | 2019-02-26 | 复旦大学 | Efficient microwave vortex light excitation apparatus based on super surface transmission geometry Bell's phase |
CN108683408B (en) * | 2018-04-13 | 2021-05-11 | 东南大学 | Time domain coding super surface with independently adjustable harmonic amplitude and phase |
-
2019
- 2019-10-28 CN CN201911030353.5A patent/CN110829033B/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105305091A (en) * | 2015-10-13 | 2016-02-03 | 复旦大学 | Tunable gradient meta-surface-based reflection electromagnetic wave modulator and design method thereof |
CN205863402U (en) * | 2016-05-19 | 2017-01-04 | 深圳超级数据链技术有限公司 | Meta Materials |
CN109935964A (en) * | 2017-12-15 | 2019-06-25 | 华为技术有限公司 | A kind of antenna element and aerial array |
CN109994838A (en) * | 2017-12-29 | 2019-07-09 | 深圳光启尖端技术有限责任公司 | A kind of controllable absorbing meta-material |
CN108511916A (en) * | 2018-02-12 | 2018-09-07 | 东南大学 | A kind of Digital Programmable space-time code Meta Materials |
CN108923814A (en) * | 2018-05-29 | 2018-11-30 | 东南大学 | It may be programmed the wireless communications method and system of Meta Materials based on time domain |
CN109067445A (en) * | 2018-09-27 | 2018-12-21 | 东南大学 | A kind of super surface of time domain coding for wireless communication |
CN110365616A (en) * | 2019-06-27 | 2019-10-22 | 东南大学 | Surpass the multi-user wireless communication system and method on surface based on space-time code |
Also Published As
Publication number | Publication date |
---|---|
CN110829033A (en) | 2020-02-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN110829033B (en) | High-efficiency electromagnetic wave frequency conversion time domain super surface | |
CN108683408B (en) | Time domain coding super surface with independently adjustable harmonic amplitude and phase | |
CN110137688B (en) | Restructural wideband phase modulation screen based on artificial magnetic conductor | |
CN109193173B (en) | Microwave band wave absorbing device and method based on phase-adjustable super surface | |
CN110034410B (en) | Multifunctional nonlinear super surface | |
CN108682964B (en) | Time domain metamaterial | |
CN110829034A (en) | Reconfigurable metamaterial basic unit and metamaterial surface | |
EP3982479A1 (en) | Metamaterial adjustable capacitor structure | |
CN112310650A (en) | Basic unit, super surface and arbitrary double-harmonic regulation and control method based on information super surface | |
CN207719402U (en) | High power flush type polarization conversion antenna house | |
CN211265719U (en) | Multifunctional super surface based on solid-state plasma regulation and control | |
CN113805150B (en) | Harmonic generation method based on time modulation active frequency selective surface | |
CN112787698A (en) | Efficient time modulation array harmonic wave beam forming system and implementation method thereof | |
CN108598710A (en) | A kind of spatial domain phase-shifting unit and the vortex wave phase plate being made from it | |
Abdo-Sanchez et al. | Reconfigurability mechanisms with scanning rate control for omega-bianisotropic Huygens’ metasurface leaky-wave antennas | |
Li et al. | Wideband reconfigurable reflectarray based on reflector-backed second-order bandpass frequency selective surface | |
CN113540811A (en) | Electromagnetic protection active frequency selection surface and control method thereof | |
JPH09181475A (en) | Composite type wide band electromagnetic wave absorber | |
CN207474683U (en) | A kind of Meta Materials and antenna | |
CN113517563A (en) | Active super surface wave beam scanning structure | |
CN109687163A (en) | Restructural phase-modulation screen based on three frequency Artificial magnetic conductor structures | |
CN107706526B (en) | High-power embedded polarization conversion radome | |
CN115149270A (en) | Broadband programmable amplitude-phase combined coding super surface | |
CN111755780B (en) | Basic unit and space phase shifter for analog signal processing constructed based on basic unit | |
CN110768016A (en) | Two-bit metamaterial periodic time sequence modulation method, metamaterial and phased array antenna |
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 |