A broadband electromagnetic stealth and illusion integrated system based on time delay

Abstract

The present invention discloses a broadband electromagnetic stealth and illusion integrated system based on delay, which relates to the field of electromagnetic control technology. The main body of the system is a control board; the control board includes a microstrip patch antenna array and a control circuit; the microstrip patch antenna array includes a metal patch antenna array, a first dielectric substrate, an air layer and a metal floor arranged in sequence, and the air layer reduces its own equivalent dielectric constant to broaden the working frequency band of the metal patch antenna array; the control circuit includes a second dielectric substrate and an adjustable gain amplifier circuit, a microstrip delay line and a power divider circuit connected in sequence on the bottom surface thereof. The stealth illusion integrated system proposed by the present invention has a simple manufacturing process and strong practicality.

Description

Technical Field

[0001] The present invention relates to the field of electromagnetic control technology, and more specifically to a broadband electromagnetic stealth and illusion integrated system based on time delay. Background Art

[0002] Electromagnetic stealth is an anti-reconnaissance technology for electromagnetic detection equipment such as radar. At present, one of the main technical approaches to electromagnetic stealth technology is electromagnetic stealth materials. There are two principles for electromagnetic stealth materials to achieve stealth for detected targets. One is to regulate the amplitude of the reflected electromagnetic wave, and reduce the amplitude of the reflected electromagnetic wave by designing absorbing materials, thereby reducing the radar cross section (RCS) and reducing the possibility of the target being detected. The other is to regulate the phase of the reflected electromagnetic wave, reshape the wavefront of the reflected wave, and simulate the reflection effect of only the background environment without the target.

[0003] Electromagnetic metasurfaces can be designed to arbitrarily control the amplitude and phase of electromagnetic waves, and because of their light weight and small size, they have become a good electromagnetic stealth material. However, since it is difficult for metasurfaces to achieve broadband control of the phase of electromagnetic waves, and the design of complex unit structures is often time-consuming and labor-intensive, a simpler method of broadband control of electromagnetic waves to achieve stealth is needed.

[0004] Therefore, how to provide a system that achieves broadband electromagnetic stealth by changing the spatial phase distribution of reflected electromagnetic waves through precise control of broadband electromagnetic waves is an urgent problem that needs to be solved by technical personnel in this field. Summary of the invention

[0005] In view of this, the present invention provides a broadband electromagnetic stealth and illusion integrated system based on time delay, which changes the spatial phase distribution of the reflected electromagnetic wave by regulating the delay of the electromagnetic wave, thereby realizing the electromagnetic stealth method. In theory, infinite broadband electromagnetic stealth can be realized (actually limited by the bandwidth of the device used). The adjustable gain amplifier integrated in the control board of the present invention can adjust the amplitude of the reflected electromagnetic wave as needed, thereby changing the far-field radiation pattern of the reflected wave, and realizing the effect of electromagnetic stealth and illusion.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A broadband electromagnetic stealth and illusion integrated system based on delay,

[0008] The main body of the system is the control panel;

[0009] The control board includes a microstrip patch antenna array and a control circuit;

[0010] The microstrip patch antenna array comprises a metal patch antenna array, a first dielectric substrate, an air layer and a metal floor arranged in sequence, wherein the air layer broadens the working frequency band of the metal patch antenna array by reducing its own equivalent dielectric constant; the control circuit comprises a second dielectric substrate and an adjustable gain amplifier circuit, a microstrip delay line and a power divider circuit which are connected in sequence and carried on the bottom surface thereof.

[0011] Preferably, the metal patch antenna array comprises n groups of antenna units with the same structure, wherein any one group of antenna units is used to receive electromagnetic waves incident in space, and the remaining antenna units are used to transmit electromagnetic waves processed by the system.

[0012] Preferably, the antenna unit is a monopole antenna structure and is fed by bottom feeding; the metal patch of the antenna unit includes two rectangles, one of which has an I-shaped groove, and the other rectangle is in vertical contact with the feeding column; the other end of the feeding column passes through the metal floor and is connected to the corresponding position of the microstrip line on the bottom surface of the second dielectric substrate, and an isolation ring is correspondingly dug out on the metal floor; the design process of the antenna unit specifically includes:

[0013] determining material properties of the first dielectric substrate;

[0014] Designing the size parameters of the metal patch according to the material properties of the first dielectric substrate to determine the working frequency band of the antenna;

[0015] Designing the thickness of the dielectric layer and the thickness of the air layer of the antenna unit;

[0016] The position of the feeding post of the antenna unit, the diameter of the feeding post, and the diameter of the isolation ring on the metal floor are designed to achieve impedance matching with the metal patch so that the reflection coefficient S11 of the antenna unit is less than -10dB within the working frequency band.

[0017] Preferably, the electromagnetic wave delay of the microstrip delay line is achieved by accurately designing its length, and the specific process includes:

[0018] Determine the width of the microstrip delay line according to the thickness and material properties of the second dielectric substrate, so as to achieve impedance matching with the adjustable gain amplifier circuit and the power divider circuit;

[0019] The length of each microstrip delay line is determined according to the required electromagnetic wave delay time.

[0020] Preferably, the adjustable gain amplifier circuit is printed on the bottom surface of the second dielectric substrate; the gain of the adjustable gain amplifier circuit is regulated by a DC voltage.

[0021] Preferably, the power divider circuit is composed of two-stage one-to-two power dividers to form a one-to-four power divider, which is used to evenly divide the processed electromagnetic waves and transmit them using the transmitting antenna unit.

[0022] Preferably, the design process of the power divider circuit includes:

[0023] Determining the width of the microstrip line in the power divider circuit according to the thickness and material properties of the second dielectric substrate;

[0024] The circuit structure of the designed one-to-four power distributor is symmetrical to ensure that its four outputs are of equal amplitude and phase.

[0025] According to the system operating frequency band, the model of the power divider chip is determined by comprehensively considering the amplitude balance, phase balance, return loss and insertion loss indicators of the control circuit.

[0026] Preferably, the regulating plate is placed at an angle to the ground, and an object is hidden in the space below the regulating plate.

[0027] Preferably, the design and simulation of the microstrip patch antenna array, microstrip delay line, and power divider circuit are performed in electromagnetic simulation software.

[0028] Preferably, a method of a broadband electromagnetic stealth and illusion integrated system based on delay is also included, wherein electromagnetic waves incident in space are received from any group of antenna units set in the microstrip patch antenna array, and are delayed by the microstrip delay line and amplitude modulated by the adjustable gain amplifier circuit in the control circuit of the control board, and the electromagnetic waves are radiated into space through the remaining antenna units of the microstrip patch antenna array; by adjusting the delay length of the delay line and the gain size of the adjustable gain amplifier, the shape and direction of the wavefront of the radiated electromagnetic wave and its far-field radiation pattern can be arbitrarily designed.

[0029] Through the above technical solutions, it can be known that in order to solve the problems of complex design and narrow working frequency band of electromagnetic metasurface stealth cloak, the present invention discloses a delay-based broadband electromagnetic stealth and illusion integrated system, in which the microstrip delay line integrated in the system can adjust the phase of broadband electromagnetic waves by delay, and the adjustable gain amplifier can change the far-field radiation pattern of the system by amplitude modulation, thereby achieving the effect of electromagnetic stealth and illusion; the system provided by the present invention can achieve good electromagnetic stealth and illusion effects in the microwave band, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 A hierarchical structure diagram of the control panel provided by the present invention;

[0032] Figure 2 A schematic diagram of a control circuit provided by the present invention;

[0033] Figure 3 A schematic diagram of a transceiver antenna array provided by the present invention;

[0034] Figure 4 A schematic diagram of near-field simulation results of the control panel provided by the present invention operating at a frequency of 2.9 GHz;

[0035] Figure 5 A schematic diagram of near-field simulation results of the control panel provided by the present invention operating at a frequency of 3.5 GHz;

[0036] Figure 6 A schematic diagram of near-field simulation results of the control panel provided by the present invention operating at a frequency of 4.0 GHz;

[0037] Figure 7 A comparison diagram of changes in the far-field pattern of radiation power of eight rows of transmitting antennas provided by the present invention;

[0038] Figure 8 Schematic diagram of the electromagnetic stealth function of the control panel provided by the present invention. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The embodiment of the present invention discloses a broadband electromagnetic stealth and illusion integrated system based on time delay, comprising: the system body is a control panel, which is a symmetrically placed control panel in the embodiment of the present invention;

[0041] Specifically, Figure 1-2 As shown, the control board includes a microstrip patch antenna array and a control circuit arranged in sequence;

[0042] The microstrip patch antenna array comprises a metal patch antenna array, a first dielectric substrate, an air layer and a metal floor arranged in sequence, wherein the air layer broadens the working frequency band of the metal patch antenna array by reducing its own equivalent dielectric constant; the control circuit comprises a second dielectric substrate and an adjustable gain amplifier circuit, a microstrip delay line and a power divider circuit which are connected in sequence and carried on the bottom surface thereof.

[0043] Specifically, the material of the first dielectric substrate selected in the embodiment of the present invention is FR-4, with a thickness of 0.5 mm; the material of the second dielectric substrate is Rogers4003C, with a thickness of 0.508 mm; and there is an air layer with a thickness of 1.5 mm between the two dielectric substrates.

[0044] Specifically, Figure 3 As shown, the metal patch antenna array includes n groups of antenna units with the same structure, wherein any one group of antenna units is used to receive electromagnetic waves incident in space, and the remaining antenna units are used to transmit electromagnetic waves processed by the system.

[0045] Specifically, the antenna unit is a monopole antenna structure and is fed by bottom feeding; the metal patch of the antenna unit includes two rectangles, one of which has an I-shaped groove, and the other rectangle is in vertical contact with the feeding column; the other end of the feeding column passes through the metal floor and is connected to the corresponding position of the microstrip line on the bottom surface of the second dielectric substrate, and an isolation ring is correspondingly dug out on the metal floor; the design process of the antenna unit specifically includes:

[0046] determining material properties of the first dielectric substrate;

[0047] Designing the size parameters of the metal patch according to the material properties of the first dielectric substrate to determine the working frequency band of the antenna;

[0048] Designing the thickness of the first dielectric substrate and the thickness of the air layer of the antenna unit;

[0049] The position of the feeding post of the antenna unit, the diameter of the feeding post, and the diameter of the isolation ring on the metal floor are designed to achieve impedance matching with the metal patch so that the reflection coefficient S11 of the antenna unit is less than -10dB within the operating frequency band, that is, the standing wave ratio of the antenna unit is minimized.

[0050] Furthermore, the positional relationship between the feed post and the antenna unit in the embodiment of the present invention is confirmed by simulation parameter scanning.

[0051] Specifically, the microstrip delay line realizes electromagnetic wave delay by accurately designing its length, and the specific process includes:

[0052] The width of the microstrip delay line is determined according to the thickness and material properties of the second dielectric substrate to achieve impedance matching with the adjustable gain amplifier circuit and the power divider circuit; the length of each microstrip delay line is determined according to the required electromagnetic wave delay time.

[0053] Furthermore, the delay in the embodiment of the present invention is achieved by a microstrip line with a precisely designed length; there are a total of 8 delay lines of different lengths in the embodiment of the present invention, and their delay amounts are determined according to the stealth requirements; specifically, according to the height difference between the ground and the control board, that is, the difference in the distance the electromagnetic wave propagates in the air , calculate the time difference of electromagnetic waves propagating in the air ,in is the speed of light in free space, This is the delay of the delay line.

[0054] Specifically, the adjustable gain amplifier circuit is printed on the bottom surface of the second dielectric substrate; the gain of the adjustable gain amplifier circuit is regulated by a direct current voltage.

[0055] Specifically, the power divider circuit is composed of two-stage one-to-two power dividers to form a one-to-four power divider, which is used to evenly divide the processed electromagnetic waves and transmit them using the transmitting antenna unit.

[0056] Specifically, the design process of the power divider circuit includes:

[0057] Determining the width of the microstrip line in the power divider circuit according to the thickness and material properties of the second dielectric substrate;

[0058] The designed one-to-four power divider circuit structure is symmetrical, ensuring that its four outputs are of equal amplitude and phase;

[0059] According to the system operating frequency band, the model of the power divider chip is determined by comprehensively considering the amplitude balance, phase balance, return loss and insertion loss indicators of the control circuit.

[0060] Specifically, the control panels are placed symmetrically and are placed at an angle of 20° to the ground.

[0061] Specifically, the design and simulation of the microstrip patch antenna array, microstrip delay line, and power divider circuit are performed in electromagnetic simulation software.

[0062] Further, according to the near-field simulation results of the electromagnetic simulation software in the embodiment of the present invention, Figure 4-6 As shown, it can be seen that based on the regulation of the designed microstrip delay line, the regulation board of the present invention can achieve the expected angular deflection of the direction of the radiated electromagnetic wave front; it can be seen that the system has a good electromagnetic regulation effect in the broadband range of 2.9~4GHz.

[0063] Specifically, Figure 7 As shown, by changing the radiation power of the eight rows of transmitting antennas on the control board, the simulation results of the change of the far-field pattern of the system are obtained. It can be seen that by adjusting the gain of the adjustable gain amplifier, thereby changing the radiation power of the transmitting antenna, the system can generate different far-field patterns and achieve an electromagnetic illusion effect.

[0064] Specifically, Figure 8 As shown, an embodiment of the present invention provides a broadband stealth system based on microstrip line delay control, the system consists of two identical control boards, which are symmetrically placed and respectively form a certain angle with the ground (designed to be 20°), and the triangular space below the control board can hide objects; when a detection electromagnetic wave is incident perpendicular to the ground, the receiving antenna arrays on the two control boards receive it, and after broadband phase modulation and low-noise amplifier amplitude modulation of the delay line integrated in the control board, the electromagnetic wave is finally radiated into space through the transmitting antenna array; the radiated plane electromagnetic wave, whose wavefront is parallel to the ground, simulates the effect of ground plane reflection, thereby achieving stealth; by adjusting the gain of each low-noise amplifier in the system, the amplitude of the electromagnetic wave emitted by each row of antennas can be adjusted, thereby adjusting the far-field radiation pattern of the radiated electromagnetic wave, and achieving the effect of electromagnetic illusion.

[0065] In summary, the system designed by the present invention realizes the electromagnetic stealth function in the 2.9~4GHz frequency band, and has the characteristics of integration and miniaturization. Compared with the traditional metasurface stealth cloak that performs phase control on electromagnetic waves, this design has the advantage of broadband (theoretically, it can reach infinite bandwidth), and the far-field pattern of the system can be changed by gain control of the adjustable gain low-noise amplifier, so that this stealth system also has the function of illusion. The integrated stealth illusion system proposed by the present invention has a simple manufacturing process and strong practicality, and is suitable for the future needs of integrated and integrated microwave stealth illusion.

[0066] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0067] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A broadband electromagnetic stealth and illusion integrated system based on time delay, characterized in that: The main body of the system is the control panel; The control board includes a microstrip patch antenna array and a control circuit; The microstrip patch antenna array comprises a metal patch antenna array, a first dielectric substrate, an air layer and a metal floor arranged in sequence, wherein the air layer widens the working frequency band of the metal patch antenna array by reducing its own equivalent dielectric constant; the control circuit comprises a second dielectric substrate and an adjustable gain amplifier circuit, a microstrip delay line and a power divider circuit which are connected in sequence and carried on the bottom surface thereof; The metal patch antenna array includes n groups of antenna units with the same structure, wherein any one group of antenna units is used to receive electromagnetic waves incident in space, and the remaining antenna units are used to transmit electromagnetic waves processed by the system; The antenna unit is a monopole antenna structure and is fed by bottom feeding; the metal patch of the antenna unit includes two rectangles, one of which has an "I"-shaped groove, and the other rectangle is in vertical contact with the feeding column; the other end of the feeding column passes through the metal floor and is connected to the corresponding position of the microstrip line on the bottom surface of the second dielectric substrate, and an isolation ring is correspondingly dug out on the metal floor; The design process of the antenna unit specifically includes: determining material properties of the first dielectric substrate; Designing the size parameters of the metal patch according to the material properties of the first dielectric substrate to determine the working frequency band of the antenna; Designing the thickness of the dielectric layer and the thickness of the air layer of the antenna unit; The position of the feeding post of the antenna unit, the diameter of the feeding post, and the diameter of the isolation ring on the metal floor are designed to achieve impedance matching with the metal patch so that the reflection coefficient S11 of the antenna unit is less than -10dB within the working frequency band.

2. According to claim 1, a broadband electromagnetic stealth and illusion integrated system based on delay is characterized in that: The microstrip delay line realizes electromagnetic wave delay by accurately designing its length. The specific process includes: Determine the width of the microstrip delay line according to the thickness and material properties of the second dielectric substrate, so as to achieve impedance matching with the adjustable gain amplifier circuit and the power divider circuit; The length of each microstrip delay line is determined according to the required electromagnetic wave delay time.

3. The broadband electromagnetic stealth and illusion integrated system based on time delay according to claim 1 is characterized in that: The adjustable gain amplifier circuit is printed on the bottom surface of the second dielectric substrate; the gain of the adjustable gain amplifier circuit is regulated by a direct current voltage.

4. The broadband electromagnetic stealth and illusion integrated system based on time delay according to claim 1 is characterized in that: The power divider circuit is composed of two-stage one-to-two power dividers to form a one-to-four power divider, which is used to evenly divide the processed electromagnetic waves and transmit them using the transmitting antenna unit.

5. A broadband electromagnetic stealth and illusion integrated system based on time delay according to claim 4, characterized in that: The design process of the power divider circuit includes: Determining the width of the microstrip line in the power divider circuit according to the thickness and material properties of the second dielectric substrate; The circuit structure of the designed one-to-four power divider is symmetrical to ensure that its four outputs are of equal amplitude and phase. According to the system operating frequency band, the model of the power divider chip is determined by comprehensively considering the amplitude balance, phase balance, return loss and insertion loss indicators of the control circuit.

6. The broadband electromagnetic stealth and illusion integrated system based on time delay according to claim 1 is characterized in that: The regulating plate is placed at an angle to the ground, and an object is hidden in the space below the regulating plate.

7. The broadband electromagnetic stealth and illusion integrated system based on time delay according to claim 1 is characterized in that: The design and simulation of the microstrip patch antenna array, microstrip delay line, and power divider circuit are performed in electromagnetic simulation software.

8. A method for applying the delay-based broadband electromagnetic stealth and illusion integrated system according to any one of claims 1 to 7, characterized in that: Any group of antenna units set up in the metal patch antenna array receives electromagnetic waves incident in the space, which are delayed by the microstrip delay line and amplitude modulated by the adjustable gain amplifier circuit in the control circuit of the control board, and radiated into the space through the remaining antenna units of the metal patch antenna array; by adjusting the delay time of the delay line and the gain of the adjustable gain amplifier, the shape and direction of the wavefront of the radiated electromagnetic wave and its far-field radiation pattern can be arbitrarily designed.

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