阅读说明：本技术 一种动态波束扫描透射型编码超表面阵列 (Dynamic beam scanning transmission type coding super-surface array ) 是由 张福恒 顾昊 刘兵 张凯华 余欢 樊康 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种动态波束扫描透射型编码超表面阵列,其包含若干个周期性排列的超表面单元,超表面单元包含依次叠放的：第一金属贴片、第一介质基板、第二金属贴片、第二介质基板、第三金属贴片等,第一金属贴片的偏置线与第二金属贴片连接,第一金属贴片的第一矩形金属贴片与所述第三金属贴片的第二矩形金属贴片连接,通过在第三金属贴片的馈线加载不同的偏置电压,以使各超表面单元达到预设的透射幅度和相位分布,采用FPGA预编码动态控制加载的偏置电压,实现透射电磁波动态波束扫描。其优点是：其通过对底层的第三金属贴片加载偏置电压,不需要额外的偏置电路层,具有大角度快速扫描、宽带、超薄、低成本的特性,整体结构简单、轻质、易加工。(The invention discloses a dynamic beam scanning transmission type coding super-surface array, which comprises a plurality of periodically arranged super-surface units, wherein the super-surface units comprise the following components in sequential stacking: the device comprises a first metal patch, a first medium substrate, a second metal patch, a second medium substrate, a third metal patch and the like, wherein a bias line of the first metal patch is connected with the second metal patch, a first rectangular metal patch of the first metal patch is connected with a second rectangular metal patch of the third metal patch, different bias voltages are loaded on a feeder line of the third metal patch so that each super-surface unit can reach preset transmission amplitude and phase distribution, and the loaded bias voltages are dynamically controlled by adopting FPGA precoding, so that transmission electromagnetic wave dynamic beam scanning is realized. The advantages are that: the third metal patch on the bottom layer is loaded with bias voltage, an additional bias circuit layer is not needed, the broadband ultra-thin high-speed scanning broadband low-cost high-speed scanning broadband low-voltage high-speed printed circuit board has the advantages of being simple in overall structure, light in weight and easy to process.)

1. A dynamic beam scanning transmission type coded super-surface array is characterized by comprising a plurality of super-surface units which are periodically arranged, wherein the super-surface units comprise the following components which are sequentially stacked: a first metal patch for receiving electromagnetic waves, a first medium substrate, a second metal patch for generating a bias current closed loop, a second medium substrate, and a third metal patch for radiating electromagnetic waves, wherein the first metal patch is positioned at the top, the third metal patch is positioned at the bottom,

the first metal patch comprises a rectangular square ring, a first rectangular metal patch and a bias line, wherein the first rectangular metal patch is arranged in the rectangular square ring and is connected with the rectangular square ring through two switch diodes, and the bias line is connected with the rectangular square ring;

the third metal patch comprises a second rectangular metal patch and a feeder line, and the second rectangular metal patches of adjacent super-surface units are connected through the feeder line;

the bias line of the first metal patch is connected with the second metal patch, the first rectangular metal patch of the first metal patch is connected with the second rectangular metal patch of the third metal patch, different bias voltages are loaded on the feeder line of the third metal patch, so that each super-surface unit achieves preset transmission amplitude and phase distribution, the loaded bias voltages are dynamically controlled by adopting FPGA precoding, and transmission electromagnetic wave dynamic beam scanning is realized.

2. The dynamic beam scanning transmissive coded super surface array of claim 1,

when TE polarized electromagnetic waves in the air are incident to one side surface of the coding super-surface array, each super-surface unit of the coding super-surface array generates resonance and radiates out from the other side surface of the coding super-surface array; when TM polarized electromagnetic waves in the air are incident to one side surface of the coding super surface array, the TM polarized electromagnetic waves are subjected to total reflection.

3. The dynamic beam scanning transmissive coded super surface array of claim 1,

the first rectangular metal patch and the two switch diodes of the rectangular square ring are arranged in the same direction according to the cathode or the anode, and the switch diodes are equivalent to a resistor under the condition of conduction and equivalent to a capacitor under the condition of cutoff; the bias lines are arranged along the x axis, one end of each bias line is connected with the middle of the rectangular square ring, and the other end of each bias line is connected with the second metal patch through the first metal cylinder.

4. The dynamic beam scanning transmissive coded super surface array according to claim 1 or 3,

the first rectangular metal patch is different in length and width, the rectangular square ring is different in length and width, and the widths of the side edges of the rectangular square ring are equal; the length of the bias line is 1/4 of the wavelength corresponding to the working center frequency.

5. The dynamic beam scanning transmissive coded super surface array of claim 1,

a first through hole is formed in the second metal patch, a second metal cylinder penetrates through the first through hole to connect the first rectangular metal patch with the second rectangular metal patch, and the second metal cylinder is not in contact with the second metal patch;

the plane size of the second metal patch is the same as the period of the super-surface unit.

6. The dynamic beam scanning transmissive coded super surface array of claim 1,

a U-shaped groove is etched in a second rectangular metal patch of the third metal patch, and the U-shaped groove is symmetrical about the y axis; the length and the width of the second rectangular metal patch are not equal; and the second rectangular metal patches of the adjacent super-surface units are connected through feeders which are arranged along the x-axis direction, and the feeders are arranged at the zero potential positions of the alternating voltage of the second rectangular metal patches.

7. The dynamic beam scanning transmissive coded super surface array of claim 1,

the encoded super-surface array carries out compensation phase calculation of focusing pretreatment according to formula 1, and the unit phase with the compensation phase delta psi exceeding 360 degrees is subjected to modulus taking according to 360 degrees, wherein m and n are serial numbers of super-surface units respectively, p is a super-surface unit period, L is the geometric distance between the phase center of a feed source antenna and the super-surface center, and lambda is the free space wavelength corresponding to the working center frequency,

8. the dynamic beam scanning transmissive coded super surface array of claim 1,

the two switch diodes are respectively a first switch diode and a second switch diode, when the third metal patch is connected with positive voltage, the state is defined as 0, at the moment, the first switch diode is conducted, and the second switch diode is cut off; when the third metal patch is connected with a negative voltage, the state is defined as 1, at the moment, the first switch diode is cut off, and the second switch diode is conducted; the transmitted electromagnetic waves of state 0 and state 1 are equal in amplitude and 180 ° out of phase.

9. The dynamic beam scanning transmissive coded super surface array of claim 8,

carrying out phase quantization on the focusing compensation phase of each super-surface unit of the coded super-surface array according to a formula 2, wherein the compensation phase delta psi is processed according to the compensation phase 0 DEG between 0 DEG and 180 DEG, the corresponding super-surface unit is in a state 0, namely the first switch diode is turned on, and the second switch diode is turned off; the compensation phase delta psi is processed between 180 DEG and 360 DEG according to the compensation phase 180 DEG, the corresponding super surface unit is in a state 1, namely the first switch diode is cut off, the second switch diode is conducted,

10. the dynamic beam scanning transmissive coded super surface array of claim 1,

taking each n rows of super-surface units of the coded super-surface array as a sub-array, wherein n is 2,3 and 4 …, coding the super-surface units divided by the sub-array according to a certain rule, and finally performing phase superposition on a quantization compensation phase and a coding phase, wherein the superposition complies with the following rule: "0 °" + "0 °" -0 ° "," 0 ° "+" 180 ° "-180 °", "180 °" -0 ° ".

Technical Field

The invention relates to the technical field of microwave frequency band electromagnetic wave regulation, in particular to a novel dynamic beam scanning transmission type coding super-surface array.

Background

Beam scanning is an important function of an array antenna, and compared with a fixed beam array antenna with a beam direction always kept unchanged, the array antenna with the beam scanning function is usually used in military facilities such as missiles, warships, ground radars and the like for detecting and identifying rapid multiple targets in a complex environment, or in mobile communication equipment such as intelligent vehicles, mobile phones and the like for high-speed and multi-channel broadband communication.

Conventional antenna beam scanning approaches include mechanical scanning and electronic scanning. Wherein, the mechanical scanning is realized by controlling the steering of the antenna through a mechanical rotating device, such as a parabolic reflector antenna. The antenna has simple feeding mode and low maintenance cost, but the equipment is heavy and bulky, so that the system response speed is low, the scanning range is small, a plurality of targets cannot be tracked simultaneously, the integral reliability of the antenna system is reduced, and the modern communication and military requirements of quick scanning and tracking cannot be met. Electronic scanning refers to phased array antennas, each antenna element being followed by a T/R (Transmitter/Receiver) component (including phase shifters and attenuators). The beam direction synthesized by the array antenna is controlled by adjusting the phase of the phase shifter and the amplitude of the attenuator. Because the phase shifter and the attenuator are controlled by a computer, the feeding phase change of the antenna unit is quick in response, and the feeding amplitude of the unit is adjustable, so that the synthesized beam has the advantages of quick and adjustable pointing, high data resolution, strong anti-interference capability and the like. However, phased array antennas require a large number of T/R components, and the T/R components are highly lossy, making the phased array antennas expensive, inefficient, and complex feed networks. In addition, the T/R component has narrow bandwidth, which greatly limits the performance of the broadband antenna. Therefore, a new type of beam scanning structure that is convenient for practical use is required.

Disclosure of Invention

The invention aims to provide a dynamic beam scanning transmission type coding super-surface array, which combines a plurality of periodically arranged super-surface units, wherein each super-surface unit comprises a first metal patch, a first medium substrate, a second metal patch, a second medium substrate and a third metal patch, and the third metal patch on the bottom layer is loaded with bias voltage, so that the dynamic beam scanning transmission type coding super-surface array does not need an additional deflection circuit layer, has the characteristics of quick scanning, broadband, ultra-thinness and low cost, and has a simple integral structure, light weight and easy processing.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a dynamic beam scanning transmission type coded super-surface array comprises a plurality of super-surface units which are periodically arranged, wherein the super-surface units comprise the following components which are sequentially stacked: a first metal patch for receiving electromagnetic waves, a first medium substrate, a second metal patch for generating a bias current closed loop, a second medium substrate, and a third metal patch for radiating electromagnetic waves, wherein the first metal patch is positioned at the top, the third metal patch is positioned at the bottom,

the first metal patch comprises a rectangular square ring, a first rectangular metal patch and a bias line, wherein the first rectangular metal patch is arranged in the rectangular square ring and is connected with the rectangular square ring through two switch diodes, and the bias line is connected with the rectangular square ring;

the third metal patch comprises a second rectangular metal patch and a feeder line, and the second rectangular metal patches of adjacent super-surface units are connected through the feeder line;

the bias line of the first metal patch is connected with the second metal patch, the first rectangular metal patch of the first metal patch is connected with the second rectangular metal patch of the third metal patch, different bias voltages are loaded on the feeder line of the third metal patch, so that each super-surface unit achieves preset transmission amplitude and phase distribution, the loaded bias voltages are dynamically controlled by adopting FPGA precoding, and transmission electromagnetic wave dynamic beam scanning is realized.

Optionally, when TE polarized electromagnetic waves in the air are incident on one side surface of the encoded super-surface array, each super-surface unit of the encoded super-surface array generates resonance and radiates out from the other side surface of the encoded super-surface array; when TM polarized electromagnetic waves in the air are incident to one side surface of the coding super surface array, the TM polarized electromagnetic waves are subjected to total reflection.

Optionally, the first rectangular metal patch and the two switching diodes of the rectangular square ring are arranged in the same direction as the cathode or the anode, and the switching diodes are equivalent to a resistor when being turned on and are equivalent to a capacitor when being turned off; the bias lines are arranged along the x axis, one end of each bias line is connected with the middle of the rectangular square ring, and the other end of each bias line is connected with the second metal patch through the first metal cylinder.

Optionally, the length and the width of the first rectangular metal patch are different, the length and the width of the rectangular square ring are different, and the widths of the side edges of the rectangular square ring are equal; the length of the bias line is 1/4 of the wavelength corresponding to the working center frequency.

Optionally, a first through hole is formed in the second metal patch, a second metal cylinder penetrates through the first through hole to connect the first rectangular metal patch with the second rectangular metal patch, and the second metal cylinder is not in contact with the second metal patch;

the plane size of the second metal patch is the same as the period of the super-surface unit.

Optionally, a U-shaped groove is etched in the second rectangular metal patch of the third metal patch, and the U-shaped groove is symmetrical about the y-axis; the length and the width of the second rectangular metal patch are not equal; and the second rectangular metal patches of the adjacent super-surface units are connected through feeders which are arranged along the x-axis direction, and the feeders are arranged at the zero potential positions of the alternating voltage of the second rectangular metal patches.

Optionally, the encoded super-surface array performs compensation phase calculation of focusing preprocessing according to formula 1, and modulo the unit phase with the compensation phase Δ ψ exceeding 360 ° according to 360 °, where m and n are serial numbers of the super-surface unit, p is a super-surface unit period, L is a geometric distance between a phase center of the feed antenna and a super-surface center, λ is a free space wavelength corresponding to a working center frequency,

optionally, the two switching diodes are respectively a first switching diode and a second switching diode, when the third metal patch is connected to a positive voltage, a state 0 is defined, at this time, the first switching diode is turned on, and the second switching diode is turned off; when the third metal patch is connected with a negative voltage, the state is defined as 1, at the moment, the first switch diode is cut off, and the second switch diode is conducted; the transmitted electromagnetic waves of state 0 and state 1 are equal in amplitude and 180 ° out of phase.

Optionally, the focusing compensation phase of each super-surface unit of the coded super-surface array is subjected to phase quantization according to formula 2, wherein the compensation phase Δ ψ is processed according to the compensation phase 0 ° between 0 ° and 180 °, the corresponding super-surface unit is in a state of 0, that is, the first switching diode is turned on, and the second switching diode is turned off; the compensation phase delta psi is processed between 180 DEG and 360 DEG according to the compensation phase 180 DEG, the corresponding super surface unit is in a state 1, namely the first switch diode is cut off, the second switch diode is conducted,

optionally, each n rows of super-surface units of the coded super-surface array are used as a sub-array, where n is 2,3, and 4 …, the super-surface units divided by the sub-array are coded according to a certain rule, and finally, the quantization compensation phase and the coding phase are subjected to phase superposition, where the superposition complies with the following rule: "0 °" + "0 °" -0 ° "," 0 ° "+" 180 ° "-180 °", "180 °" -0 ° ".

Compared with the prior art, the invention has the following advantages:

according to the dynamic beam scanning transmission type coding super-surface array, a plurality of periodically arranged super-surface units are combined, each super-surface unit comprises a first metal patch, a first medium substrate, a second metal patch, a second medium substrate and a third metal patch, and by loading bias voltage on the third metal patch at the bottom layer, an additional bias circuit layer is not needed, so that the structure is simple, and the cost is low.

Furthermore, the super-surface unit only has two thin medium layers without introducing an air layer, and has the characteristic of low profile. And the metal patches of each layer of the super-surface unit are tightly coupled to form a third-order band and filter response, so that the working bandwidth is effectively expanded. In addition, the loaded bias voltage is dynamically controlled through FPGA precoding, the beam direction of the transmission electromagnetic wave can be flexibly controlled, large-angle beam scanning is realized, and the method has wide application prospects in the fields of antennas, imaging, communication systems, electromagnetic countermeasure, military stealth and the like.

Drawings

FIG. 1 is a schematic diagram of the overall three-dimensional structure of a super-surface unit according to the present invention;

FIG. 2 is a schematic view of a first metal patch of the present invention;

FIG. 3 is a schematic view of a second metal patch of the present invention;

FIG. 4 is a schematic view of a third metal patch of the present invention;

FIG. 5 is a schematic perspective view of a super-surface unit according to the present invention;

FIG. 6 is a simulation result of return loss of the dynamic beam scanning transmission type coded super-surface array according to the present invention;

FIG. 7 is a simulation result of transmission coefficient of the dynamic beam scanning transmission type coded super surface array according to the present invention;

FIG. 8 is a simulation result of the transmission phase of the dynamic beam scanning transmission type coded super-surface array according to the present invention;

FIG. 9 is a schematic diagram of the distribution of the phase compensation for the focus of the dynamic beam scanning transmission type coded super-surface array according to the present invention;

FIG. 10 is a diagram of the dynamic beam scanning transmission type coded super surface array 1-bit quantized focus compensation phase distribution of the present invention;

FIG. 11 is a compensated phase distribution corresponding to the transmission type coded super surface array "01010101" code of dynamic beam scanning of the present invention;

FIG. 12 is the phase distribution of the dynamic beam scanning transmission type coded super surface array after 1-bit quantization and the superposition of the focusing phase and the '01010101' coding phase;

FIG. 13 shows the simulation results of the return loss before and after the horn antenna is loaded with the dynamic beam scanning transmissive coded super-surface array;

FIG. 14 is a simulation result of the dynamic beam scanning transmission type coded super surface array "00000000" coded normalized radiation pattern of the present invention;

FIG. 15 is a simulation result of the dynamic beam scanning transmission type coded super-surface array "01010101" coded normalized radiation pattern of the present invention.

Detailed Description

The present invention will now be further described by way of the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings.

As shown in fig. 1 to 5, a dynamic beam scanning transmission type coded super-surface array according to the present invention includes a plurality of super-surface units arranged periodically, where the super-surface units include: first metal paster 1, first medium base plate 4, second metal paster 2, second medium base plate 5, third metal paster 3, first metal paster 1 is located the top and is the top layer metal paster, third metal paster 3 is located the bottom and is the bottom metal paster, and second metal paster 2 is located between the two, for intermediate level metal horizon, wherein top layer metal paster plays the effect of receiving the electromagnetic wave, and intermediate level metal horizon plays the effect that produces the closed loop of bias current, and bottom metal paster plays the effect of radiating the electromagnetic wave, and two medium base plates play the effect of support. In this embodiment, each super-surface unit of the dynamic beam scanning transmission type coded super-surface array (called coded super-surface array for short) has the same structure.

The first metal patch 1 comprises a rectangular square ring 1-2, a first rectangular metal patch 1-3 and a bias line 1-1, wherein the first rectangular metal patch 1-3 is arranged inside the rectangular square ring 1-2 and is connected with the rectangular square ring 1-2 through two switch diodes 1-4. One end of the bias line 1-1 is connected with the rectangular square ring 1-2, and the other end of the bias line is connected with the second metal patch 2 through the first metal cylinder 4-1. The third metal patch 3 comprises a second rectangular metal patch 3-2 and a feeder 3-1, and the second rectangular metal patches 3-2 of adjacent super-surface units are connected through the feeder 3-1. The first rectangular metal patch 1-3 of the first metal patch 1 is connected with the second rectangular metal patch 3-2 of the third metal patch 3 through a second metal cylinder 4-2.

The bias line 1-1 on the first metal patch 1 is used for introducing bias current to the second metal patch 2 to form a closed loop, the rectangular square ring 1-2 is used for receiving electromagnetic waves with required frequency, and the first rectangular metal patch 1-3 is used for connecting two switching diodes. The feeder 3-1 on the third metal patch 3 is used for introducing bias voltage, and the second rectangular metal patch 3-2 is used for radiating electromagnetic waves with required frequency. When a bias voltage (such as a positive voltage) is loaded on the feeder line 3-1 on the third metal patch 3, the generated bias current flows to the first rectangular metal patch 1-3 on the first metal patch 1 through the second metal cylinder 4-2, so that one of the two switching diodes 1-4 is in a conducting state, the other one is in a stopping state, and the bias current flows to the second metal patch 2 through the first metal cylinder 4-1 to generate a closed loop. The electromagnetic wave irradiated on the first metal patch 1 is radiated by the second rectangular metal patch 3-2 on the third metal patch 3. When an opposite bias voltage is applied to the feeding line 3-1 on the third metal patch 3 (i.e. a negative voltage), the two switching diodes 1-4 are in opposite working states (i.e. the switching diode turned on by applying a positive bias voltage is in a cut-off state by applying a negative bias voltage). At this time, the electromagnetic wave of the rectangular square ring 1-2 irradiated on the first metal patch 1 is radiated by the second rectangular metal patch 3-2 on the third metal patch 3, but the phase of the radiated electromagnetic wave is 180 ° different from the phase of the electromagnetic wave radiated by the positive voltage. Therefore, different control voltages are loaded to enable each super-surface unit of the coded super-surface array to achieve preset, namely expected transmission amplitude (close to 1) and phase distribution (0 degree or 180 degrees), and the loaded bias voltage is dynamically controlled by utilizing FPGA precoding, so that transmission electromagnetic wave dynamic beam scanning is realized.

The super-surface unit is only provided with two thin dielectric layers without introducing an air layer, and has the characteristic of low profile. And the metal patches of each layer of the super-surface unit are tightly coupled to form a third-order band and filter response, so that the working bandwidth is effectively expanded. In addition, the super-surface unit loads bias voltage by using the bottom metal patch without introducing an additional bias circuit layer, and has the advantages of simple structure, low cost and the like.

In the embodiment, when TE polarized electromagnetic waves in the air are incident to one side surface (a top layer or a bottom layer) of the coding super-surface array, each super-surface unit of the coding super-surface array generates resonance and radiates out from the other side surface of the coding super-surface array; when TM polarized electromagnetic waves in the air are incident to one side surface (a top layer or a bottom layer) of the coding super-surface array, the TM polarized electromagnetic waves are subjected to total reflection.

In this embodiment, the working frequency band of the super-surface unit is the X-band, and the whole size of the coded super-surface array is 216 × 216 × 3mm³(length × width × height).

Further, as shown in fig. 2, the centers of the first rectangular metal patch 1-3 and the rectangular square ring 1-2 coincide, the two switching diodes 1-4 of the first rectangular metal patch 1-3 and the rectangular square ring 1-2 are arranged in the same direction as the cathode or the anode (the switching diodes 1-4 may be made of MADP-000907 manufactured by MA/COM corporation), one end of the switching diode 1-4 is connected to the middle position of one side of the first rectangular metal patch 1-3, and the other end is connected to the middle position of one side of the rectangular square ring 1-2.

The length and the width of the first rectangular metal patch 1-3 are not equal, the length and the width of the rectangular square ring 1-2 are not equal, the width of each side ring of the rectangular square ring 1-2 is equal, the length of the rectangular square ring 1-2 determines the resonance frequency, the width of the rectangular square ring 1-2 adjusts the impedance, the length of the first rectangular metal patch 1-3 is determined by the size needed by the welding switch diode 1-4, and the width of the first rectangular metal patch 1-3 plays a role in adjusting the impedance. In this embodiment, the length of the first rectangular metal patch 1-3 is 2.1mm, and the width is 2 mm; the length of the rectangular square ring 1-2 is 5.5mm, the width is 5.1mm, and the width of the side ring is 0.75 mm. The switching diodes 1-4 are equivalent to resistors with the resistance value of 0.5 omega under the condition of conduction, and equivalent to capacitors with the capacitance value of 0.05pF under the condition of cutoff.

The bias lines 1-1 are arranged along the x axis, one end of each bias line 1-1 is connected with the middle of each rectangular square ring 1-2, and the other end of each bias line 1-1 is connected with the second metal patch 2 through a first metal cylinder 4-1. The length of the bias line 1-1 is about 1/4 corresponding to the wavelength of the working center frequency, and the width of the bias line 1-1 is not too large so as to avoid influencing the performance of the metamaterial unit. In this embodiment, the first metal cylinder 4-1 has a diameter of 0.2 mm. In this embodiment, the bias line 1-1 has a length of 1.75mm and a width of 0.2 mm.

The second rectangular metal patch 3-2 of the third metal patch 3 is etched with a U-shaped groove 3-3, the U-shaped groove 3-3 is symmetrical about the y axis and consists of a horizontal gap along the x axis direction and two vertical gaps along the y axis direction, and the U-shaped groove 3-3 is used for controlling the surface current distribution of the second rectangular metal patch 3-2 and realizing impedance matching. The length and width of the second rectangular metal patch 3-2 are not equal. The second rectangular metal patches 3-2 of the adjacent super-surface units are connected through the feeder lines 3-1 arranged along the x axial direction, and the feeder lines 3-1 are arranged in the middle of the second rectangular metal patches 3-2, namely the alternating-current voltage zero potential position of the second rectangular metal patches 3-2, so that the direct-current bias voltage is prevented from generating interference on radio-frequency signals. The feeder line 3-1 should be a high-resistance line with a thin line width. In this embodiment, the length of the second rectangular metal patch 3-2 is 5.5mm, the width thereof is 7.0mm, the length of the gap in the horizontal direction of the U-shaped groove 3-3 is 2.0mm, the width thereof is 0.5mm, the length of the gap in the vertical direction thereof is 4.5mm, and the width thereof is 0.75mm, and the center of the second rectangular metal patch 3-2 coincides with the center of the U-shaped groove 3-3. The width of the feeder line 3-1 is 0.2 mm.

As shown in fig. 3 and 5, the planar size of the second metal patch 2 is the same as the super surface unit period, and in this embodiment, the size is 9.0 mm. The second metal patch 2 is provided with a first through hole, the second metal cylinder 4-2 penetrates through the first through hole to connect the first rectangular metal patch 1-3 with the second rectangular metal patch 3-2 etched with the U-shaped groove 3-3, and the second metal cylinder 4-2 is not in contact with the second metal patch 2. The coded super-surface array is formed by arranging a large number of coded super-surface units, each super-surface unit needs a metal cylinder to connect a top-layer metal patch and a bottom-layer metal patch, and the top-layer metal patch and the bottom-layer metal patch of each super-surface unit cannot be connected physically by using a conductive wire. In this embodiment, the first through hole is a circular hole having a diameter of 0.4 mm. The diameter of the second metal cylinder 4-2 is 0.2 mm.

The two switching diodes 1-4 are respectively a first switching diode PIN1 and a second switching diode PIN2, when the third metal patch 3 is connected with a positive voltage, a state 0 is defined, at this time, the first switching diode PIN1 is turned on, and the second switching diode PIN2 is turned off; when the third metal patch 3 is connected with negative voltage, the state is defined as state 1, at this time, the first switch diode PIN1 is cut off, and the second switch diode PIN2 is conducted; the transmitted electromagnetic waves of state 0 and state 1 are equal in amplitude and 180 ° out of phase.

As shown in fig. 6, in this embodiment, the super-surface unit generates three transmission zeros in both state 0 and state 1, so as to form a third-order band-to-filter response, thereby effectively expanding the transmission bandwidth. As shown in fig. 7 and 8, in this embodiment, the transmission loss simulation results of the super-surface unit in the frequency range of 8.9-11.85GHz are less than 3.0dB in both states, and the transmission phase difference in both states is close to 180 °.

As shown in fig. 1 and fig. 9, in this embodiment, the encoded super-surface array performs compensation phase calculation of focusing preprocessing according to formula (1), and modulo the unit phase with the compensation phase Δ ψ exceeding 360 ° by 360 °, where m and n are serial numbers of super-surface units, p is a super-surface unit period, L is a geometric distance between a phase center of a feed antenna and a super-surface center, λ is a free space wavelength corresponding to a working center frequency,

in this example, the super surface unit period is taken to be 9.0mm, L is taken to be 61.0mm, and λ is taken to be 27.3 mm.

As shown in fig. 1 and 10, the focus compensation phase of each super-surface cell of the coded super-surface array is subjected to phase quantization according to formula (2), wherein the compensation phase Δ ψ is processed according to the compensation phase 0 ° between 0 ° and 180 ° corresponding to the super-surface cell being in state 0, i.e., the first switching diode PIN1 is turned on, and the second switching diode PIN2 is turned off; the compensation phase delta psi is processed between 180 deg. and 360 deg. according to the compensation phase 180 deg., the corresponding super surface unit is in state 1, i.e. the first switch diode PIN1 is turned off, the second switch diode PIN2 is turned on,

taking each n rows of super-surface units of the coded super-surface array as a sub-array, wherein n is 2,3,4 …, coding the super-surface units divided by the sub-array according to a certain rule (such as coding according to '01010101'), and finally performing phase superposition on a quantization compensation phase and a coding phase, wherein the superposition complies with the following rule: "0 °" + "0 °" -0 ° "," 0 ° "+" 180 ° "-180 °", "180 °" -0 ° ". As shown in fig. 11, in this embodiment, each 3 columns of super-surface units of the coded super-surface array are used as a sub-array, and the super-surface divided by the sub-arrays is coded according to the "01010101" rule. As shown in fig. 12, the phase of the encoded super-surface array quantized compensated phase and the "01010101" regularly encoded phase are superimposed, and the superposition follows the following rule: "0 °" + "0 °" -0 ° "," 0 ° "+" 180 ° "-180 °", "180 °" -0 ° ".

Optionally, the first metal patch 1, the second metal patch 2, and the third metal patch 3 are all copper foils, and in the dynamic beam scanning transmission type coded super-surface array, the number of units of each type of metal patch in the horizontal direction is the same as that in the vertical direction. In this embodiment, the thickness of the copper foil is about 0.035mm, 24 metal patches of each type are provided in each direction, and the dielectric substrate used is ArlonAD 450, the dielectric constant is 4.5, the loss tangent angle is 0.0035, and the dielectric thickness is 1.5 mm.

When TE polarized electromagnetic waves radiated by the horn antenna are incident to the '00000000' or '01010101' coded super-surface array, each super-surface unit of the coded super-surface array generates resonance, adjacent super-surface sub-arrays are coded in the same mode, transmitted electromagnetic waves are superposed in a far field in an in-phase mode, and the transmitted electromagnetic waves are cancelled in a far field in an opposite phase mode when codes are opposite. Different bias voltages (positive voltage or negative voltage) are reasonably loaded on the third metal patch 3 by the encoding super-surface array through an FPGA (field programmable gate array) or other integrated circuits, the expected transmission amplitude (close to 1) and phase distribution (0 degree or 180 degrees) of each super-surface unit on the super-material array are completed, and the function of transmitting electromagnetic wave dynamic beam scanning is realized. In the implementation process of the embodiment, full-wave simulation software CST is used for simulation, the characteristics of the dynamic beam scanning transmission type coded super-surface unit are obtained by using periodic boundary conditions and a Floquet port, so that the requirements that the amplitudes of the electromagnetic waves transmitted in two corresponding states are equal and the phase difference is 180 degrees under different bias voltages are met, and the horn antenna is used as a feed source to simulate the characteristics of the whole super-surface array.

As shown in fig. 13, before and after the feed horn antenna is loaded on the coded super-surface array described in this embodiment, the return loss is less than-10 dB in the frequency range of 8-12 GHz.

As shown in fig. 14 and 15, the coded super-surface array of the present embodiment has normalized radiation patterns of 10GHz at both codes "00000000" and "01010101", with beam pointing at 0 ° and 30 °, respectively. Different bias voltages are preloaded by using the FPGA, other codes of the super-surface array, such as '00100100100' and '00011011', can be realized, and other beam pointing can be realized, so that electromagnetic wave dynamic beam scanning is completed.

The dynamic beam scanning transmission type coding super-surface array is adopted for simulation test, and the simulation test result shows that: within the frequency range of 8.9-11.85GHz, the transmission loss of each super-surface unit is less than 3dB, the dynamic beam scanning transmission type coding super-surface array can flexibly control the beam direction of transmission electromagnetic waves, and has wide application prospects in the fields of antennas, imaging, communication systems, electromagnetic countermeasure, military stealth and the like.

In summary, in the dynamic beam scanning transmission type coded super-surface array of the present invention, a plurality of periodically arranged super-surface units are combined, each super-surface unit includes a first metal patch 1, a first dielectric substrate 4, a second metal patch 2, a second dielectric substrate 5, and a third metal patch 3, and by loading a bias voltage on the third metal patch 3 at the bottom layer, no additional bias circuit layer is required, so that the structure is simple and the cost is low.

Furthermore, air layers are not introduced among the metal patches, the metal patches have the characteristic of ultra-thinness (3mm), the thickness corresponds to one tenth of the wavelength of 10GHz of the central frequency, the whole structure size is small, and the size of the whole super-surface unit is only three tenths of the working wavelength.

Furthermore, the invention controls the phase of the electromagnetic wave beam transmitted by the super-surface unit by utilizing the on-off of the switching diodes 1-4, controls the gain of the wave beam by superposing and focusing the phase, and does not need a high-cost T/R component to adjust the gain and the phase.

Furthermore, the invention controls different codes of the transmission type coded super-surface array through the FPGA, thereby realizing electromagnetic beam scanning which is faster than mechanical scanning response.

Furthermore, the super-surface unit provided by the invention has three independent resonance points, so that a band-pass filter characteristic with a third-order resonance characteristic is formed, and the relative bandwidth reaches 28%.

While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.