Radiation and scattering cooperative modulation antenna

Abstract

The invention relates to a radiation-scattering cooperative modulation antenna, and belongs to the technical field of antennas. Comprising a radiation feed source, an upper-layer dielectric plate, a feed network, a middle-layer dielectric plate, a lower-layer dielectric plate, a direct-current bias, a metal floor and a control circuit, the radiation feed source is printed on the upper surface of the upper-layer dielectric plate, a switching diode is loaded in the middle of the radiation feed source, the switching diode is used for adjusting the reflection phase of the radiation feed source, and switching of two modes of radiation and scattering of the antenna is achieved by changing the state of the switching diode; the feed network and the metal floor are respectively printed on the upper surface and the lower surface of the middle-layer dielectric plate; the direct current bias is arranged on the lower surface of the lower dielectric plate; and the control circuit is used for providing an optimal coding signal for determining the state distribution of the switching diode for the direct current bias, so that the direct current bias outputs a direct current signal of the switching diode according to the optimal coding signal.

Description

Technical Field

[0001] The present invention belongs to the field of antenna technology, and in particular relates to a radiation scattering cooperative modulation antenna. Background Art

[0002] The antenna in the radar system is not only an electromagnetic field radiator, but also a strong scattering source. In order to ensure the survival and information exchange of mobile carriers on the battlefield, the antenna needs to reduce the radar cross section (RCS) while ensuring its own radiation capability. In order to achieve the integrated design of radiation and scattering characteristics, it is necessary not only to build a resonant structure that undertakes the radiation function, but also to integrate the specific shape design, special dielectric materials or electronic control components required for scattering control into the same antenna. Therefore, the integrated design of radiation and scattering characteristics needs to overcome technical difficulties such as increased caliber, improved profile, deteriorated coupling and reduced efficiency. Therefore, compared with single-function radiation improvement antennas or scattering modulation antennas, antennas with integrated radiation and scattering characteristics have richer application potential and face more diverse technical challenges.

[0003] Antenna radiation and scattering are contradictory quantities. Traditional methods such as loading absorbing materials will destroy the antenna radiation environment, resulting in a decrease in antenna performance. Electromagnetic metamaterials can be used as part of the antenna and designed as an integrated part of the antenna. They can meet the low scattering performance of the antenna without reducing the antenna radiation characteristics too much, and achieve the comprehensive requirements of antenna radiation and scattering. In recent years, low RCS antenna design is often achieved by placing frequency selective surfaces, absorption units and polarization conversion units around the antenna, forming phase gradients, hybrid metasurfaces, etc., but there is often a problem that the proportion of the overall area occupied by the antenna is very small, making it difficult to obtain higher gain.

[0004] In order to modulate electromagnetic waves more flexibly, a coded metasurface (CM) is proposed to control the scattered field. CM can dynamically adjust the characteristics of electromagnetic waves to prevent being used as part of an array. It can cleverly adjust the state control components such as switching diodes, MEMS and varactor diodes that switch the radiation and scattering characteristics. This opens up a new way for antenna arrays to achieve low RCS values ​​without affecting their original radiation performance. The cells on the CM can obtain different phase responses by changing the state of the control components. By applying different coding sequences on the metasurface, the array beam can switch between different modes. However, the structure loaded with the metasurface is prone to increase the profile or increase the size, thereby reducing the antenna aperture utilization, and the RCS reduction within the antenna radiation working band is difficult to achieve.

[0005] The prior art discloses that a partial reflection surface (PRS) composed of an absorption surface (AS) and a reflection surface (RS) is used to form an FP resonant cavity with an antenna to improve the antenna gain, and a metamaterial is used to reduce the antenna RCS. The electrical size of the antenna is 3.7λ*3.7λ*0.73λ, which can achieve a gain of 18.4dBi, a -10dB impedance bandwidth of 3.9%, and a RCS reduction bandwidth of 72%. Each unit on the 9×9 absorption surface uses 4 resistors to achieve in-band absorption, so the antenna needs to use a higher profile and a complex feeding structure to achieve radiation scattering cooperative modulation, and because the bandwidth of the absorption metasurface is narrow, the antenna impedance bandwidth is narrow and the antenna efficiency is low. The prior art also discloses a low-profile antenna array with a reconfigurable parasitic ring structure, which provides a phase difference through four switching diodes on each radiating patch unit. The 8×8 antenna array can achieve 50% and 35% in-band RCS reduction under TE- and TM polarizations, respectively, and the radiation mode can achieve a -10dB impedance bandwidth of 4.8% and a maximum gain of 16.2dBi, and its aperture efficiency is 20.7%. Although the antenna has a reduced profile height, the complex DC feed network greatly increases the antenna loss and reduces the aperture utilization, and it is difficult to achieve broadband in-band RCS reduction due to the unstable in-band phase difference.

[0006] The two existing states with a phase difference of 180° are distributed in a checkerboard pattern, and the RCS reduction is limited. It is necessary to optimize the distribution of the phases to increase the RCS reduction. Summary of the invention

[0007] The technical problems to be solved by the present invention are:

[0008] In order to avoid the shortcomings of the prior art, the present invention provides a radiation scattering cooperative modulation antenna, which provides a stable and broadband phase difference within the radiation band by loading a single switching diode on a low-profile radiating element, adopts a lower antenna profile and a simple structure to achieve broadband RCS reduction, and uses a GSO group search algorithm combined with a single-chip microcomputer control circuit to optimize the array phase distribution to further reduce the RCS within the antenna band, ensure a wider impedance bandwidth, and improve the antenna aperture utilization.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A radiation scattering cooperative modulation antenna, characterized in that it includes: a radiation feed source, an upper dielectric plate, a feeding network, an intermediate dielectric plate, a lower dielectric plate, a DC bias, a metal floor, and a control circuit;

[0011] The radiation feed is printed on the upper surface of the upper dielectric plate, and a switching diode is loaded in the middle of the radiation feed. The switching diode is used to adjust the reflection phase of the radiation feed, and the switching between the two modes of antenna radiation and scattering is achieved by changing the state of the switching diode;

[0012] The feed network and the metal floor are printed on the upper surface and the lower surface of the middle layer dielectric board respectively;

[0013] The DC bias is arranged on the lower surface of the lower dielectric plate;

[0014] The control circuit is used to provide the DC bias with an optimal coding signal for determining the state distribution of the switching diode, so that the DC bias outputs a DC signal of the switching diode according to the optimal coding signal.

[0015] A further technical solution of the present invention is as follows: the control circuit includes a single-chip microcomputer, a first latch and a second latch, the serial data of the single-chip microcomputer is output to the first latch, the first latch overflows the serial data to the second latch, the first latch and the second latch output 16 voltages in parallel, and the 16 voltages are connected to a DC bias as optimal coding signals.

[0016] A further technical solution of the present invention is that the control circuit uses a group search optimization algorithm GSO to optimize the state distribution of the switch diodes in the radiation feed to obtain the optimal coding signal, specifically:

[0017] A checkerboard distribution is used as the initial state distribution of the switching diode;

[0018] Design the objective function of the group search optimization algorithm GSO:

[0019] fitness=max[E S (B)]

[0020] Among them, E S (B) is the total scattered field;

[0021] The state distribution of the switch diode is updated so that the state distribution of the corresponding switch diode is the optimal coding signal when the objective function is optimal.

[0022] A further technical solution of the present invention: the model of the single chip microcomputer is Arduino UNO R3.

[0023] A further technical solution of the present invention: the first latch and the second latch are both of model 74HC595.

[0024] A further technical solution of the present invention is as follows: the radiation feed source comprises a plurality of metal patch units distributed in an array, the metal patch unit being composed of a trapezoidal structure of upper and lower parts, and a switching diode being loaded in the gap between the upper and lower trapezoidal structures; when the diode is turned on, the two parts of the metal patch unit are equivalent to being connected; when the diode is turned off, the metal patch unit is equivalent to a gap patch.

[0025] A further technical solution of the present invention is as follows: the radiation feed source cuts the patch and connects it with a capacitor before the AC signal reaches the switching diode, so as to prevent the switching diode from being burned by the AC signal.

[0026] A further technical solution of the present invention is as follows: two square metal gaskets are loaded at the left and right ends of the metal patch unit respectively to facilitate welding of an inductor device that passes DC and blocks AC, and a metal through hole connected to the bottom layer DC bias is provided on the square metal gasket, and the metal through hole is used to provide a DC signal to the switching diode.

[0027] A further technical solution of the present invention is that the upper dielectric plate, the middle dielectric plate and the lower dielectric plate are all Rogers F4B265 with a relative dielectric constant of 2.65.

[0028] A further technical solution of the present invention: the model of the switching diode is SMP1340-040LF.

[0029] The beneficial effects of the present invention are:

[0030] The present invention provides a radiation scattering cooperative modulation antenna, which realizes the reconfigurable switching between the two states of radiation scattering of the antenna by loading a single electronic device, and the antenna performance can be quickly and dynamically adjusted according to the needs. The antenna of the present invention can achieve a wide impedance bandwidth and broadband RCS reduction, and has the advantages of low profile, small size and simple control. Compared with other radiation scattering cooperative modulation antennas, the present invention has the following advantages in performance indicators:

[0031] 1. The central operating frequency of the present invention is 10 GHz, and the electrical size is 2.2λ*2.2λ*0.13λ. Compared with the traditional method of loading the metasurface, the antenna profile is reduced by 82.2%, the total size is reduced by 50.9%, the antenna gain peak is 14.9 dB, the aperture utilization is 50.8%, and the operating frequency range is increased by 16.3%.

[0032] 2. The operating frequency band is 9.4 GHz-11.6 GHz (20.9%), which is about 17% higher than the bandwidth of the prior art. In the scattering mode, the present invention achieves significant broadband RCS reduction within the frequency range of 6 GHz-20 GHz (107.6%).

[0033] 3. The present invention provides a DC signal to the switching diode array on the array surface through the Arduino UNO R3 single-chip microcomputer. The array surface distribution can be adjusted by modifying the signal array according to the needs to achieve the reconfiguration of the scattering pattern. It is not limited to a fixed array surface distribution and does not require complicated switching means.

[0034] 4. The present invention combines the GSO group search algorithm to calculate the relationship between the antenna array phase distribution and the in-band RCS, optimizes the antenna phase distribution, and achieves further reduction of RCS in the frequency range of 9.4GHz-12GHz. Compared with the checkerboard phase distribution, the RCS value is reduced by more than 6dB on average, with a maximum reduction of 11.8dB.

[0035] 5. The unit of the present invention can achieve a broadband in-band phase difference by using only a single switching diode, which simplifies the control scheme, reduces the energy loss caused by electronic devices, is easy to process and install, and can obtain more excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0037] Figure 1 It is a structural diagram of a 4×4 array antenna according to an embodiment of the present invention.

[0038] Figure 2 It is a top view of the radiation feed unit according to an embodiment of the present invention.

[0039] Figure 3 It is a side view of the radiation feed unit according to an embodiment of the present invention.

[0040] Figure 4 Schematic diagram of a feeding network according to an embodiment of the present invention.

[0041] Figure 5 Schematic diagram of DC bias according to an embodiment of the present invention.

[0042] Figure 6 It is a schematic diagram of the principle of the microcontroller control circuit.

[0043] Figure 7 4 is a diagram showing the state distribution of the switch diode in the radiation mode according to an embodiment of the present invention.

[0044] Figure 8 3 is a state distribution diagram of the switch diode in scattering mode 1 according to an embodiment of the present invention.

[0045] Fig. 9 This is a distribution diagram of the switch diode state in scattering mode 2 according to an embodiment of the present invention.

[0046] Fig.10 It is a “reflection amplitude-frequency” response curve of the radiation feed unit of an embodiment of the present invention at a periodic boundary.

[0047] Fig.11 It is a “reflection phase-frequency” response curve of the radiation feed unit of an embodiment of the present invention at a periodic boundary.

[0048] Fig.12 This is a “reflection coefficient-frequency” response curve of the 4×4 array antenna according to an embodiment of the present invention.

[0049] Fig.13 This is the radiation pattern of the 4×4 array antenna according to an embodiment of the present invention.

[0050] Fig.14 This is a “radar cross section-frequency” response curve of the 4×4 array antenna according to an embodiment of the present invention.

[0051] In the figure:

[0052] 1-radiation feed source, 2-upper dielectric board, 3-feeding network, 4-middle dielectric board, 5-lower dielectric board, 6-DC bias, 7-metal floor. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0054] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0055] The present invention provides a radiation scattering cooperative modulation antenna, comprising a radiation feed 1, an upper dielectric plate 2, a feeding network 3, an intermediate dielectric plate 4, a metal floor 7, a lower dielectric plate 5 and a DC bias 6; the radiation feed 1 is printed on the upper surface of the upper dielectric plate 2, and a switching diode is loaded in the middle of the radiation feed 1. The switching diode can adjust the reflection phase of the radiation feed, and the switching between the two modes of antenna radiation scattering is achieved by changing the state of the switching diode. The feeding network 3 and the metal floor 7 are printed on the upper surface and the lower surface of the intermediate dielectric plate 4, respectively. In order to independently provide DC signals to different switching diodes, a DC bias layer 6 is provided on the lower surface of the lower dielectric plate 5.

[0056] Compared with the method of loading metasurface, the radiation scattering cooperative modulation antenna provided by the present invention can effectively reduce the antenna profile, improve the antenna aperture utilization, and can achieve wide-band in-band RCS reduction while having stable radiation gain and directivity pattern.

[0057] When a plane wave is incident vertically on two adjacent surfaces, the scattered waves will produce a destructive interference effect in space due to the 180° phase difference between the reflected waves, thereby reducing the antenna radar cross section (RCS). The total scattered field of an array composed of two unit surfaces in different states is expressed as:

[0058] E s =E1F1+E2F2

[0059] Among them, E1 and E2 are the unit radiation fields of the unit in the two states, F1 and F2 are the array factors of the unit in the two states, and the unit reflection phase of the switch diode in the on state is recorded as The unit reflection phase in the disconnected state is recorded as The radiation fields of these two units can be expressed as:

[0060]

[0061] Among them, A is the amplitude, E element is the basic unit radiation field.

[0062] The total scattered field

[0063]

[0064] when When the total scattered field is the smallest, the RCS reduction can be maximized under ideal conditions. In practice, to achieve a 10dB RCS reduction,

[0065] The present invention uses a group search optimization algorithm (Group Search Optimizer, GSO) to optimize the state distribution of diodes in the array to achieve better scattering performance. The group search optimization algorithm is an optimization algorithm based on group behavior and biological inspiration, which draws on the characteristics of animal group foraging behavior and social interaction. The GSO algorithm simulates the process of a group of individuals including discoverers, followers and wanderers (called "searchers") searching for the best solution in the search space. Each searcher individual moves in the search space and continuously adjusts its position through local and global information exchange to tend to the global optimal solution. By updating the position of the searcher and evaluating the fitness of the new position, the global optimal position is updated at the same time until the termination condition is met (such as reaching the maximum number of iterations or finding a good enough solution).

[0066] The array factors of the two state units in the present invention are the same, so the scattered field calculation formula of the 4×4 antenna array can be simplified to:

[0067]

[0068] Using a 4×4 matrix To represent the state of the switching diode of each unit in the array, the working state of the diode is defined as unit "1", and the cut-off state is defined as unit "0".

[0069] In the present invention, the objective function optimized by the GSO group search algorithm is:

[0070] fitness=max[E S (B)]

[0071] The initial value of each searcher is The searcher determines the next moving direction and step length based on its own and the group's fitness values. Specifically, it can be divided into three behaviors: the discoverer conducts a local search near its own position to find a new solution, the follower adjusts its position according to the position and information of other individuals, and the wanderer conducts a large-scale search to avoid falling into the local optimum. The state distribution of the diodes in the array is updated by updating the searcher's matrix B and evaluating the new fitness. The above steps are repeated until the termination condition is met (such as reaching the maximum number of iterations or the scattering field is small enough).

[0072] The present invention adopts Arduino UNO R3 single-chip microcomputer and 74HC595 latch to design external control circuit, and realizes one-key switching of antenna working state by pressing a button. In order to realize programmable array, the present invention encodes two working states of antenna unit, defines the working state of diode as unit "1", and defines the diode cut-off state as unit "0". In this way, the antenna working state can be represented by 01 matrix. First, the 01 matrix of the antenna state to be realized is programmed through Arduino IDE and burned into the control chip, and the output of multiple 01 matrices is switched by buttons. Since the output signal of Arduino is serial output, the present invention realizes parallel output of signals by cascading two 74HC595 chips, and prevents the Arduino UNO R3 single-chip microcomputer from being burned.

[0073] Embodiment 1:

[0074] like Figure 1 As shown, a radiation scattering cooperatively modulated reconfigurable antenna provided by an embodiment of the present invention is a 4×4 array antenna, comprising a radiation feed source 1, an upper dielectric plate 2, a feeding network 3, an intermediate dielectric plate 4, a lower dielectric plate 5, a DC bias 6, and a metal floor 7; the upper dielectric plate 2, the intermediate dielectric plate 4, and the lower dielectric plate 5 are sequentially arranged from top to bottom, and the three dielectric plates are laminated together. The radiation feed source 1 is located on the upper surface of the upper dielectric plate 2, the feeding network 3 is located on the upper surface of the intermediate dielectric plate 4, the metal floor 7 is located on the lower surface of the intermediate dielectric plate 4, and the DC bias 6 is located on the lower surface of the lower dielectric plate 5.

[0075] like Figure 2 As shown, the radiation feed source 1 is a plurality of metal patch units distributed in an array and printed on the upper surface of the upper dielectric plate 2. The metal patch unit is composed of a trapezoidal structure of upper and lower parts, and a switching diode is loaded in the gap between the upper and lower trapezoidal structures. When the diode is turned on, the two parts of the metal patch unit are equivalent to being connected; when the diode is turned off, the metal patch unit is equivalent to a gap patch. The reflection phase of the two metal patch units has a stable reflection phase difference of 180°±37° in the frequency band range of 8.3-12GHz.

[0076] Preferably, the upper dielectric plate 2 is Rogers F4B265 with a relative dielectric constant of 2.65 and a thickness of 3 mm.

[0077] Preferably, the model of the switching diode is SMP1340-040LF.

[0078] Specifically, each metal patch is a stepped patch that is symmetrical up and down, and the width of each step is L1=12mm, L2=10mm, L3=6mm, L4=4mm. The gap width in the middle of the patch unit is g1=0.6mm. The two symmetrical trapezoidal patches are separated by a gap of width g2 at the position of width W2 to control the phase difference caused by the change of the state of the switching diode. In order to ensure that there is a reflection phase difference of about 180° in the radiation band, W1=3.1mm, W2=2.1mm, g2=0.2mm; by loading a gap along the Y-axis direction on the patch, the impedance bandwidth of the antenna can be increased, L5=0.2mm, L6=0.4mm, W3=2.5mm; in order to isolate the AC circuit from the DC circuit, the patch is cut and connected using two capacitors before the AC signal reaches the switching diode to prevent the switching diode from being burned by the AC signal, wherein g3=0.4mm, W4=1.5mm.

[0079] According to the center frequency of the antenna being 10 GHz, other structural parameters of the 4×4 array antenna are: length and width P=15 mm, upper dielectric height h1=3 mm, middle dielectric and lower dielectric height h2=0.5 mm; the center frequency of the antenna design is 10 GHz.

[0080] The antenna array of 4×4 scale composed of diode-conducting units can achieve the radiation state in the X-band. The on and off states of the switching diode make the reflection phase of the metal patch unit differ by 180°±37° in the frequency range of 8.3-12GHz. Therefore, the phase cancellation principle can be used to arrange the antenna units with the switching diode turned on and the antenna units with the diode turned off in the array in a checkerboard distribution, so as to reduce the radar cross section RCS of the array in a wideband range. Two square metal gaskets are loaded on the left and right of the metal patch unit to facilitate the welding of the inductor device that passes DC and isolates AC. A metal through hole is set under each of the left and right gaskets to connect to the bottom layer DC bias 6, which is used to provide a DC signal to the switching diode loaded on the patch; in order to isolate the AC signal, the patch needs to be cut open and replaced with a capacitor device that passes AC and isolates DC to prevent the AC signal from flowing into the DC path and the DC signal from flowing into the AC path.

[0081] like Figure 4 As shown, the one-to-sixteen feed network 3 corresponding to the 4×4 array of the antenna in this embodiment is composed of 8 one-to-two power dividers, which provide equally divided and in-phase feed signals for the 4×4 array. A metal through hole is set on the trapezoidal patch on the upper side of the radiation feed source 1 to connect to the feed line of the feed network 3 to achieve better impedance matching. The metal floor 7 is printed on the lower surface of the intermediate layer medium 4 to ensure that the antenna is unidirectional radiation.

[0082] Preferably, the middle layer dielectric plate 4 is Rogers F4B265 with a relative dielectric constant of 2.65 and a thickness of 0.5 mm.

[0083] In order to independently provide DC signals to different switching diodes, a DC bias 6 is provided on the lower surface of the lower dielectric plate 6 and isolated by the lower dielectric plate 5. Figure 5 As shown, the DC bias 6 is composed of 17 groups of independent metal DC paths, among which 16 groups of paths are connected to the DC signal VCC at one end, and the other end is connected to the inductor devices connected to the forward direction of the 16 groups of switching diodes. Since the DC signal output by the single-chip microcomputer is generally 5V, the 16 groups of paths are loaded with 300 ohm resistors to prevent the switching diodes from being burned out and ensure that they can work normally when turned on; the remaining 1 group of paths short-circuits the negative direction of the switching diodes on the 16 units and is connected to the DC ground together.

[0084] Preferably, the lower dielectric plate 5 is Rogers F4B265 with a relative dielectric constant of 2.65 and a thickness of 0.5 mm.

[0085] Figure 6 The schematic diagram of the circuit control principle of the single-chip microcomputer of the present invention is given. The digital I / O pin of the Arduino UNO R3 single-chip microcomputer, namely PD2 / INT0, outputs a serial signal. The voltage value of each DC signal is 5V, which is input to the data input port DS of 74HC595. One 74HC595 outputs 8-bit digital signals in parallel. Therefore, two 74HC595s are required for the 16-bit signal required by the array. The data is cascaded to the second 74HC595 through the serial data output pin Q7S of the first 74HC595 and output in parallel. In order to visually observe the working state of each diode in the array, an LED indicator is connected before the signal is connected to the bias circuit of the diode. Through the indicator, it can be intuitively judged whether the working state of the diode in the antenna array is correctly controlled.

[0086] The embodiment of the present invention forms a 4×4 array with an antenna size of 66mm×66mm×4mm. 16 units need to be loaded with 16 different switching diodes, and each switching diode is independently controlled. By adjusting the state distribution of 16 groups of diodes, the array can exhibit a radiation mode or different scattering modes to achieve an antenna array with coordinated modulation of radiation and scattering. Specifically, the switch diode is set to "1" when it is turned on and "0" when it is turned off. Figure 7 The state distribution of 16 switch diodes of the antenna array of the present invention in the radiation mode is given, that is, all 16 switch diodes are turned on; Figure 8 and Fig. 9The state distributions of the 16 switch diodes in scattering mode 1 and scattering mode 2 are given respectively. That is, in scattering mode 1, the on-state and off-state of the 16 switch diodes are distributed in a checkerboard pattern. In scattering mode 2, the optimal state distribution of the switch diodes is obtained by optimizing the GSO group search algorithm.

[0087] Fig.10 and Fig.11 The reflection amplitude and reflection phase of the radiation feed unit of the antenna of the present invention when the switching diode is turned on and off, and the reflection amplitude in both states is less than -1.1dB, so that the antenna of the present invention has a smaller loss; at the same time, the reflection phases in the two states differ by 180°±37° in the frequency range of 8.3GHz-12GHz, which meets the phase conditions for achieving in-band broadband RCS reduction.

[0088] Fig.12 The "S11-frequency" response curve measured when the 4×4 array antenna of this embodiment is in the radiation mode, that is, when all 16 groups of switching diodes are in the on state, is given. Its -10dB impedance bandwidth is 9.38-11.58GHz, and the relative bandwidth is 20.99%.

[0089] Fig.13 The measured radiation pattern of the 4×4 array antenna in the radiation mode of this embodiment is given. The maximum gain of the antenna in the radiation mode is 14.94 dBi, and the antenna aperture utilization is 50.8%.

[0090] Fig.14 The "RCS reduction-frequency" response curves of the antenna 4×4 array of this embodiment in scattering mode 1 and scattering mode 2 are given. Compared with the copper plate of the same size, the frequency range of RCS reduction of the antenna in scattering mode 1 with checkerboard distribution is 6.8GHz-20GHz (98.5%); the frequency range of RCS reduction of the antenna in scattering mode 2 with optimized distribution is 6GHz-20GHz (107.6%), and its RCS is further reduced in the frequency range of 9.2GHz-12.8GHz, with a maximum reduction of 22dB.

[0091] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A radiation scattering cooperative modulation antenna, characterized in that: include: Radiation feed source (1), upper dielectric plate (2), feeding network (3), middle dielectric plate (4), lower dielectric plate (5), DC bias (6), metal floor (7), control circuit; The radiation feed source (1) is printed on the upper surface of the upper dielectric plate (2), and a switching diode is loaded in the middle of the radiation feed source (1). The switching diode is used to adjust the reflection phase of the radiation feed source (1), and the switching between the two modes of antenna radiation and scattering is achieved by changing the state of the switching diode; The feed network (3) and the metal floor (7) are printed on the upper surface and the lower surface of the middle layer dielectric plate (4) respectively; The DC bias (6) is arranged on the lower surface of the lower dielectric plate (5); The control circuit is used to provide the DC bias (6) with an optimal coding signal for determining the state distribution of the switching diode, so that the DC bias (6) outputs a DC signal of the switching diode according to the optimal coding signal.

2. The radiation scattering cooperative modulation antenna according to claim 1, characterized in that: The control circuit comprises a single chip microcomputer, a first latch and a second latch, the serial data of the single chip microcomputer is output to the first latch, the first latch overflows the serial data to the second latch, the first latch and the second latch output 16 voltages in parallel, and the 16 voltages are connected to a DC bias (6) as an optimal coding signal.

3. The radiation scattering cooperative modulation antenna according to claim 2, characterized in that: The control circuit uses a group search optimization algorithm GSO to optimize the state distribution of the switch diodes in the radiation feed (1) to obtain the optimal coding signal, specifically: A checkerboard distribution is used as the initial state distribution of the switching diode; Design the objective function of the group search optimization algorithm GSO: fitness=max[E S (B)] Among them, E S (B) is the total scattered field; The state distribution of the switch diode is updated so that the state distribution of the corresponding switch diode is the optimal coding signal when the objective function is optimal.

4. The radiation scattering cooperative modulation antenna according to claim 2, characterized in that: The model of the single chip microcomputer is Arduino UNO R3.

5. The radiation scattering cooperative modulation antenna according to claim 2, characterized in that: The first latch and the second latch are both of type 74HC595.

6. The radiation scattering cooperative modulation antenna according to claim 1, characterized in that: The radiation feed source (1) comprises a plurality of metal patch units distributed in an array, wherein the metal patch unit is composed of a trapezoidal structure of upper and lower parts, and a switching diode is loaded in the gap between the upper and lower trapezoidal structures; when the diode is turned on, the two parts of the metal patch unit are equivalent to being connected; when the diode is turned off, the metal patch unit is equivalent to a gap patch.

7. The radiation scattering cooperative modulation antenna according to claim 6, characterized in that: The radiation feed source (1) cuts the patch and connects it with a capacitor before the AC signal reaches the switching diode, thereby preventing the switching diode from being burned by the AC signal.

8. The radiation scattering cooperative modulation antenna according to claim 6, characterized in that: Two square metal gaskets are loaded on the left and right ends of the metal patch unit to facilitate welding of an inductor device that transmits DC and isolates AC. A metal through hole connected to the bottom layer DC bias (6) is set on the square metal gasket, and the metal through hole is used to provide a DC signal to the switching diode.

9. The radiation scattering cooperative modulation antenna according to claim 1, characterized in that: The upper dielectric plate (2), the middle dielectric plate (4) and the lower dielectric plate (5) are all Rogers F4B265 with a relative dielectric constant of 2.

65.

10. The radiation scattering cooperative modulation antenna according to claim 1, characterized in that: The model of the switching diode is SMP1340-040LF.

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