Folding SIW fast two-dimensional frequency scanning antenna based on cyclic progressive phase shift network

Abstract

The invention relates to a folding SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, and relates to the technical field of communication antennas. The antenna structure comprises a first-layer metal sheet, a first-layer dielectric substrate, a second-layer metal sheet, a second-layer dielectric substrate, a third-layer metal sheet, a third-layer dielectric substrate, a fourth-layer metal sheet, a fourth-layer dielectric substrate and a fifth-layer metal sheet. The first-layer metal sheet serves as a radiation structure, and a rectangular radiation groove is etched on the radiation structure; rectangular slot arrays are etched on the second-layer metal sheet, the third-layer metal sheet and the fourth-layer metal sheet, are used for cross-layer transmission between two adjacent layers and form an I-shaped folded SIW waveguide slow-wave structure and a cyclic progressive phase-shift network cavity together with the metalized via holes; the working frequency band of the antenna is 9.4 GHz-10.2 GHz, the beam scanning range with the gain loss smaller than 3 dB can cover a 135-degree * 150-degree two-dimensional area, the scanning rate in the phi direction is 18.3 degrees / %, the scanning rate in the theta direction is 16.5 degrees / %, and when the working frequency is 9.59 GHz, the peak gain is 7.73 dBi.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of wireless communication and relates to a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network. BACKGROUND

[0002] With the rapid development of wireless communication, radar detection and imaging, satellite internet and other technologies, modern wireless systems have made unprecedented high-performance requirements for flexible beam angle scanning antennas, and more and more application scenarios require antennas to have the ability to perform beam scanning in one or two dimensions. Methods for realizing beam scanning include mechanical control, phased array antennas, multi-beam design, frequency scanning and the like. Among them, leaky-wave antennas, as a kind of traveling-wave antenna, have attracted much attention due to their unique beam scanning mechanism without the need for complex feed networks and phase shifters.

[0003] In recent years, frequency scanning antennas have attracted widespread attention from scholars at home and abroad, and various design methods for frequency scanning have been proposed. However, the current designs are mainly for one-dimensional frequency scanning, which is limited in beam scanning range and lacks beam control capability in the other dimension. Therefore, frequency scanning antennas with two-dimensional scanning capability have important research value in radar detection and imaging. SUMMARY

[0004] The application needs to solve the technical problem of how to propose a low-profile, high-scanning-rate, two-dimensional frequency scanning folded substrate integrated waveguide (SIW) fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network.

[0005] To solve the above technical problems, the application adopts the following technical solutions: A folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, which is composed of a folded electromagnetic wave transmission path, a radiation structure and a cyclic progressive phase shift network. The antenna structure is sequentially composed of a first layer of metal sheet (1), a first layer of dielectric substrate (2), a second layer of metal sheet (3), a second layer of dielectric substrate (4), a third layer of metal sheet (5), a third layer of dielectric substrate (6), a fourth layer of metal sheet (7), a fourth layer of dielectric substrate (8) and a fifth layer of metal sheet (9). Furthermore, the proposed folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network is placed along the x-axis; sixteen identical rectangular radiating slots (101) are etched on the surface of the first metal sheet (1) along the y-axis; a second-layer rectangular slot array (301) composed of thirty-two rectangular slots is etched on the surface of the second metal sheet (3) for cross-layer energy transfer between the first and second layers; the proposed third metal sheet (5) has microstrip line extension portions (501) and microstrip line extension portions (502) at both ends, serving as feed junctions. The structure consists of a third layer of rectangular slot array (503) consisting of thirty-two rectangular slots etched on the surface of the third layer metal sheet (5), which is used for cross-layer energy transfer between the second and third layers; the fourth layer metal sheet (7) has metal extensions (701) and metal extensions (702) at both ends, which serve as the ground plane of the power supply structure, and rectangular slots (703) and rectangular slots (704) are etched on its surface, which are used for cross-layer energy transfer between the third and fourth layers; the fifth layer metal sheet (9) is a rectangular metal sheet without any slots etched on it, which serves as the ground plane of the SIW cavity; Furthermore, when energy is fed into the folded electromagnetic wave transmission path from the microstrip line extension (501), the electromagnetic wave propagates in a linearly polarized traveling wave mode in the SIW waveguide cavity. It crosses the first dielectric substrate (2), the second dielectric substrate (4), and the third dielectric substrate (6) multiple times through the second rectangular slot array (301) and the third rectangular slot array (503), forming an "I"-shaped folded SIW waveguide slow wave structure. This structure can extend the electromagnetic field path between units under the condition of fixed unit spacing. l ; Furthermore, the cyclic progressive phase shift network has an L-shaped path. The rectangular slots (703) and (704) are used to couple the power between the third dielectric substrate (6) and the fourth dielectric substrate (8). When the electromagnetic wave reaches the end of the first column through the folded electromagnetic wave transmission path, the energy is coupled to the cyclic progressive phase shift network through the rectangular slots (703) etched on the fourth metal sheet (7) and transmitted to the rectangular slots (704) etched on the fourth metal sheet (7). The energy is then fed into the second column structure through coupling. Further, a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, first layer metallized via holes (102) connect the first layer metal sheet (1) and the second layer metal sheet (3) to form the SIW side wall, the diameter rh of the first layer metallized via hole (102) and the center distance dh of the adjacent metallized via hole (102) satisfy the conditions of dh < λg and rh less than λg / 5, where λg is the medium wavelength, used to form a closed transmission structure similar to a traditional rectangular waveguide, constituting sixteen unit radiation cavities; the second layer metallized via hole (302) connects the second layer metal sheet (3) and the third layer metal sheet (5), and at the same time the third layer metallized via hole (502) connects the third layer metal sheet (5) and the fourth layer metal sheet (7), constituting a folded electromagnetic wave transmission path to expand the phase difference between units; the fourth layer metallized via hole (704) connects the fourth layer metal sheet (7) and the fifth layer metal sheet (9) to form a cyclic progressive phase shift network cavity. Further, in order to obtain good impedance matching, metallized via holes (505) and metallized via holes (705) are placed at the curved corners of the folded electromagnetic wave transmission path and the cyclic progressive phase shift network as curved corner transition structures; Further, a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, the periodic arrangement of the rectangular radiation slot (101) will cause the excitation of surface waves at a certain frequency point, forming an open stop band effect, resulting in that the energy cannot be effectively radiated and is forced to be reflected back to the feed port; in order to suppress the open stop band effect, a matching metallized via hole (103) is arranged at the side of the rectangular radiation slot (101) to adjust the matching of the rectangular radiation slot (101) and improve the frequency scanning beam radiation blind spot; Further, a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, the first layer dielectric substrate (2), the second layer dielectric substrate (4), the third layer dielectric substrate (6), and the fourth layer dielectric substrate (8) of the antenna all adopt TFA615, with a relative dielectric constant of 6.15 and a positive loss tangent of 0.0016; the thicknesses of the first layer dielectric substrate (2), the second layer dielectric substrate (4), the third layer dielectric substrate (6), and the fourth layer dielectric substrate (8) are all 0.813 mm; Further, a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, when the input electromagnetic wave frequency changes, the beam will scan in a two-dimensional plane, according to the formula:

[0006] wherein θ is the main beam direction of the antenna array, φ is the phase difference between adjacent radiation units, kFor wave number, d This represents the spatial distance between adjacent radiating elements in the antenna array. l The physical length of the transmission line connecting two adjacent radiating units is λg, where λg is the wavelength of the medium. m It is an integer representing the order of the phase period. φ 0 represents a fixed initial phase, and c represents the speed of light in vacuum. When the feed phase difference between array elements and the path difference reaching the target point cancel each other out, the waves emitted by each array element will superimpose to form the main beam. If l If it remains constant, changing the frequency will cause a change in the wavelength relative to the medium wavelength, where... l The longer the beam length, the more sensitive the beam is to frequency changes; the folded electromagnetic wave transmission path provides a phase difference in the x-direction for the antenna, and under the condition of equal element spacing, the beam length is extended by folding. l The length of the antenna allows for a higher scan rate in the x-direction, thus increasing the antenna's beam pointing angle. θ The beam pointing changes in the xoy plane; the cyclic asymptotic phase-shifting network introduces beam pointing changes in the yoz plane for the antenna, which, together with the folded electromagnetic wave transmission path, achieves two-dimensional frequency scanning. Furthermore, a foldable SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network has the ability to perform two-dimensional beam scanning as the frequency changes. The operating frequency band is 9.4 GHz–10.2 GHz, with a relative bandwidth of 8.2%. When the frequency changes within the operating frequency band, the beam pointing will deflect, and when the beam scans to… φ At the end of the direction, the beam will then re-enter φ Refocusing begins at the direction start point. During beam refocusing, a gain decrease occurs. A beam scanning range with a gain loss of less than 3 dB can cover a 135° × 150° two-dimensional area. φ The directional scan rate is 18.3° / %. θ The directional scan rate is 16.5° / %, and the peak gain is 7.73 dBi when the operating frequency is 9.59 GHz. At this time, the maximum beam pointing is (-1°, -18°).

[0007] Compared with the prior art, the present invention has the following advantages: 1. The folded SIW fast two-dimensional frequency scanning antenna based on the cyclic progressive phase shift network of the present invention extends the electromagnetic field path between radiating units through the "I"-shaped folded SIW waveguide slow wave structure and the multi-layer coupling, which has the advantages of small size, compact structure, excellent electrical performance and high scanning rate, and is suitable for small base stations and microwave imaging scenarios. 2. The folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application realizes two-dimensional expansion of the frequency scanning antenna through the cyclically progressive phase shift network design, has the advantages of high flexibility and two-dimensional high-speed scanning, and can meet the demand for wide-angle scanning coverage in base stations and imaging applications. 3. The folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application selects TFA615 material with a thickness of 0.813 mm as the dielectric substrate, which is low in cost in high-frequency plates, and is easy to mass produce and apply on a large scale. BRIEF DESCRIPTION OF DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows: Figure 1 The overall structure of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0009] Figure 2 The first layer structure top view of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0010] Figure 3 The second layer structure top view of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0011] Figure 4 The third layer structure top view of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0012] Figure 5 The fourth layer structure top view of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0013] Figure 6 The simulation reflection coefficient amplitude of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0014] Figure 7 The simulation gain amplitude varying with frequency of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application.

[0015] Figure 8 The beam pointing diagram at different frequencies of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase shift network according to the present application. DETAILED DESCRIPTION

[0016] The application will be described in further detail below with reference to the embodiments and drawings.

[0017] Referring to Figure 1 As shown in the figure, a folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network, the structure is sequentially from top to bottom: the first layer of metal sheet (1), the first layer of dielectric substrate (2), the second layer of metal sheet (3), the second layer of dielectric substrate (4), the third layer of metal sheet (5), the third layer of dielectric substrate (6), the fourth layer of metal sheet (7), the fourth layer of dielectric substrate (8), the fifth layer of metal sheet (9); the folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network is placed along the x-axis.

[0018] Further, as Figure 2 shown, there are sixteen rectangular radiation slots (101) with the same shape placed along the y-axis etched on the surface of the first layer of metal sheet (1), each rectangular slot has a width of 0.8 mm and a length of 6.8 mm; as Figure 3 shown, the second layer of rectangular slot array (301) composed of thirty-two rectangular slots is etched on the surface of the second layer of metal sheet (3), each rectangular slot has a width of 1.3 mm and a length of 6.6 mm, used for cross-layer transmission of energy between the first layer and the second layer; as Figure 4 shown, the proposed third layer of metal sheet (5) is provided with a microstrip line extension part (501) and a microstrip line extension part (502) at both ends, which are used as a feeding structure, in order to facilitate the matching of the SMA connector and the antenna structure, the characteristic impedance of the extension part microstrip line is set to 50 Ω, and the second layer of rectangular slot array (301) composed of thirty-two rectangular slots is etched on the surface of the third layer of metal sheet (5), used for cross-layer transmission of energy between the second layer and the third layer, which has the same size as the rectangular slot array (301); as Figure 5 shown, the fourth layer of metal sheet (7) has metal extensions (701) and (702) at both ends, which are used as the ground plane of the feeding structure, and at the same time, rectangular slots (703) and (704) are etched on the surface, which have the same size as the rectangular slot array (301) and the rectangular slot array (503), used for cross-layer transmission of energy between the third layer and the fourth layer; the fifth layer of metal sheet (9) is a rectangular metal sheet, which has no etching of any slot on it, and is used as the ground plane of the SIW cavity.

[0019] Furthermore, the first dielectric substrate (2), second dielectric substrate (4), third dielectric substrate (6), and fourth dielectric substrate (8) of the folded SIW fast two-dimensional frequency scanning antenna based on the cyclic progressive phase shift network are all made of TFA615, with a relative permittivity of 6.15 and a positive loss tangent of 0.0016; the thickness of the first dielectric substrate (2), second dielectric substrate (4), third dielectric substrate (6), and fourth dielectric substrate (8) is 0.813 mm.

[0020] like Figure 2 As shown, the first layer of metallized vias (102) of the folded SIW fast two-dimensional frequency scanning antenna based on a cyclic progressive phase shift network connects the first layer metal sheet (1) and the second layer metal sheet (3) to form the SIW sidewall. The diameter of the metallized via (102) is rh=0.3 mm and the center spacing of adjacent metallized vias (102) is dh=0.9 mm. It is used to form a closed transmission structure similar to a traditional rectangular waveguide, constituting sixteen unit radiation cavities. The matching metallized via (103) is located on the side of the rectangular radiation slot (101) and is used to adjust the impedance matching of the rectangular radiation slot (101). Figure 3 , Figure 4 As shown, the second layer metallized via (302) connects the second layer metal sheet (3) and the third layer metal sheet (5), while the third layer metallized via (502) connects the third layer metal sheet (5) and the fourth layer metal sheet (7), forming a folded electromagnetic wave transmission path to widen the phase difference between units; as shown Figure 5 As shown, the fourth metallized via (704) connects the fourth metal sheet (7) and the fifth metal sheet (9) to form a cyclic progressive phase shift network cavity; and a metal via (705) is placed at the bend corner as a corner transition structure.

[0021] Furthermore, the folded electromagnetic wave transmission path is formed when energy is fed in from the microstrip line extension (501), and crosses the first dielectric substrate (2), the second dielectric substrate (4), and the third dielectric substrate (6) multiple times through the second layer rectangular slot array (301) and the third layer rectangular slot array (503), forming an "I"-shaped folded SIW waveguide slow wave structure, which can extend the electromagnetic field path between units under the condition of fixed unit spacing; the cyclic progressive phase shift network is an L-shaped path. When the electromagnetic wave reaches the end of the first column through the folded electromagnetic wave transmission path, it introduces the energy into the cyclic progressive phase shift network through the rectangular slot (703) etched on the fourth layer metal sheet (7) and transmits it to the rectangular slot (704) etched on the fourth layer metal sheet (7), and feeds the energy into the second column structure through coupling.

[0022] Preferred, such as Figure 6As shown, the folding SIW fast two-dimensional frequency scanning antenna based on the cyclic progressive phase shift network has the ability of two-dimensional beam scanning with frequency variation, and has good matching effect in the working frequency band of 9.4 GHz-10.2 GHz (relative bandwidth of 8.16%); as Figure 7 shown, when the frequency varies in the working frequency band, the beam pointing will be deflected, and when the beam is scanned to the end position of φ , the beam will be refocused at the start end of φ , as shown Figure 8 , in the process of beam refocusing, there will be a phenomenon of gain decline, and the beam scanning range with gain loss less than 3 dB can cover a two-dimensional area of 135°x150°, φ , the scanning rate in the direction of θ is 16.54° / %, and when the working frequency is 9.59 GHz, the peak gain is 7.73 dBi, and at this time the maximum beam pointing is (-1°, -18°).

[0023] From the above, it can be seen that the present application has the characteristics of small size, compact structure, excellent electrical performance and two-dimensional high-speed scanning, and can be well applied in the field of wireless communication and microwave imaging scene.

[0024] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be limited by the protection scope of the claims.

Claims

1. A folded SIW fast two-dimensional frequency scanning antenna based on a cyclically progressive phase-shift network, characterized in that: The antenna is composed of a folded electromagnetic wave transmission path, a radiation structure and a cyclic progressive phase shift network, and the antenna is sequentially composed of a first layer metal sheet (1), a first layer dielectric substrate (2), a second layer metal sheet (3), a second layer dielectric substrate (4), a third layer metal sheet (5), a third layer dielectric substrate (6), a fourth layer metal sheet (7), a fourth layer dielectric substrate (8) and a fifth layer metal sheet (9) from top to bottom. The proposed folded SIW fast two-dimensional frequency scanning antenna based on the cyclic progressive phase shift network is placed along the x axis; sixteen rectangular radiation slots (101) with the same shape are etched on the surface of the first layer metal sheet (1) and placed along the y axis; a second layer rectangular slot array (301) composed of thirty-two rectangular slots is etched on the surface of the second layer metal sheet (3) and used for cross-layer transmission of energy between the first layer and the second layer; the proposed third layer metal sheet (5) is provided with a microstrip line extension part (501) and a microstrip line extension part (502) at both ends as a feeding structure, and a third layer rectangular slot array (503) composed of thirty-two rectangular slots is etched on the surface of the third layer metal sheet (5) and used for cross-layer transmission of energy between the second layer and the third layer; the fourth layer metal sheet (7) has a metal extension (701) and a metal extension (702) at both ends as a ground plane of the feeding structure, and a rectangular slot (703) and a rectangular slot (704) are etched on the surface at the same time and used for cross-layer transmission of energy between the third layer and the fourth layer; the fifth layer metal sheet (9) is a rectangular metal sheet without any etched slot thereon and serves as a ground plane of the SIW cavity. For the folded electromagnetic wave transmission path, when energy is fed from the microstrip line extension part (501), electromagnetic waves are transmitted in a linearly polarized traveling wave mode in the SIW waveguide cavity, cross the first layer dielectric substrate (2), the second layer dielectric substrate (4) and the third layer dielectric substrate (6) multiple times through the second layer rectangular slot array (301) and the third layer rectangular slot array (503), forming a "H" shaped folded SIW waveguide slow wave structure, which can extend the inter-element electromagnetic field path under the condition of fixed unit spacing l ; The cyclic progressive phase shift network is in the form of an L-shaped path, and the rectangular slot (703) and the rectangular slot (704) are used for coupling power between the third layer dielectric substrate (6) and the fourth layer dielectric substrate (8); when the electromagnetic wave reaches the end of the first column through the folded electromagnetic wave transmission path, the energy is coupled to the cyclic progressive phase shift network through the rectangular slot (703) etched on the fourth layer metal sheet (7) and transmitted to the rectangular slot (704) etched on the fourth layer metal sheet (7), and the energy is fed into the second column structure through coupling.

2. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: The first layer metalized via hole (102) connects the first layer metal sheet (1) and the second layer metal sheet (3) to form a SIW sidewall, the diameter rh of the first layer metalized via hole (102) and the center distance dh of adjacent metalized via holes (102) satisfy the conditions of dh < λg and rh < λg / 5, where λg is the dielectric wavelength, which is used to form a closed transmission structure similar to a traditional rectangular waveguide and constitutes sixteen unit radiation cavities; the second layer metalized via hole (302) connects the second layer metal sheet (3) and the third layer metal sheet (5), and the third layer metalized via hole (502) connects the third layer metal sheet (5) and the fourth layer metal sheet (7), which constitutes a folded electromagnetic wave transmission path for expanding the phase difference between units; the fourth layer metalized via hole (704) connects the fourth layer metal sheet (7) and the fifth layer metal sheet (9) to form a cyclic progressive phase shift network cavity.

3. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: The metalized via (505) and the metalized via (705) are arranged at the bending corner of the folded electromagnetic wave transmission path and the cyclic progressive phase shift network as a bending corner transition structure.

4. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: The periodic arrangement of the rectangular radiation slots (101) can cause surface waves to be excited at a specific frequency, forming an open stopband effect, resulting in energy being unable to be effectively radiated and being forced to be reflected back to the feed port; the matching metalized via (103) is arranged at the side of the rectangular radiation slot (101) and is used for adjusting the matching of the rectangular radiation slot (101) and improving the frequency scanning beam radiation blind spot.

5. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: The first layer dielectric substrate (2), the second layer dielectric substrate (4), the third layer dielectric substrate (6) and the fourth layer dielectric substrate (8) of the antenna all adopt TFA615, the relative dielectric constant is 6.15, and the positive loss tangent value is 0.0016; the thicknesses of the first layer dielectric substrate (2), the second layer dielectric substrate (4), the third layer dielectric substrate (6) and the fourth layer dielectric substrate (8) are all 0.813 mm.

6. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: When the frequency of the input electromagnetic wave changes, the beam will scan in a two-dimensional plane, according to the formula: wherein, theta is the antenna array main beam pointing, phi is the phase difference between adjacent radiating elements, k is the wave number, d is the spatial distance between adjacent radiating elements in the antenna array, l is the physical length of the transmission line connecting two adjacent radiating elements, and λgis the medium wavelength, m is an integer representing the order of the phase period, phi 0 is a fixed initial phase, and c is the speed of light in a vacuum. When the feed phase difference between the array elements and the wave path difference to the target point offset, the wave emitted by each array element will superimpose to form a main beam, if l remains unchanged, when the frequency changes, it will cause the change of the wavelength and the medium wavelength, wherein l the longer the length, the more sensitive the beam to frequency changes; wherein the folded electromagnetic wave transmission path provides the antenna with a phase difference in the x direction and expands the l length under the condition of equal element spacing, so that the antenna has a higher scanning rate in the x direction, so that the beam pointing angle θ of the antenna changes in the xoy plane; the cyclic progressive phase shift network introduces the beam pointing change in the yoz plane for the antenna, which works together with the folded electromagnetic wave transmission path to realize two-dimensional frequency scanning.

7. The folded SIW fast two-dimensional frequency scanning antenna based on cyclically progressive phase-shift network of claim 1, wherein: The antenna has the capability to perform two-dimensional beam scanning as the frequency changes, operating in the 9.4 GHz-10.2 GHz frequency band. When the frequency changes within the operating band, the beam direction will deflect, and when the beam scans to... phi At the end of the direction, the beam will then re-enter phi Refocusing begins at the direction start point. During beam refocusing, a gain decrease occurs. A beam scanning range with a gain loss of less than 3 dB can cover a 135° × 150° two-dimensional area. phi The directional scan rate is 18.3° / %. theta The directional scan rate is 16.5° / %, and the peak gain is 7.73 dBi when the operating frequency is 9.59 GHz. At this time, the maximum beam pointing is (-1°, -18°).

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