Log-periodic antenna and device based on double-helix transmission loading rectangular patch

Abstract

The invention provides a log-periodic antenna and equipment based on a double-helix transmission loading rectangular patch. The log-periodic antenna comprises a dielectric substrate; a pair of metalized through holes are formed in the dielectric substrate in a penetrating manner, and a differential feed port is formed in the bottom of each metalized through hole; a metal grounding layer is arranged on the bottom surface of the dielectric substrate; the top surface of the dielectric substrate is provided with a pair of spiral transmission lines, one end of each spiral transmission line is connected with the top of the corresponding metalized through hole, and log-periodic rectangular patches are distributed on the spiral transmission lines. According to the invention, the 90-degree phase difference is naturally generated in the broadband by adopting the form of the double-spiral transmission line and utilizing the spiral phase delay characteristic, and the axial ratio bandwidth can be improved by combining the radiation optimization of the log-periodic rectangular patch.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a logarithmic periodic antenna based on double-helix transmission loaded with a rectangular patch. Background Art

[0002] Compared to linearly polarized antennas, circularly polarized antennas offer several advantages. For example, they can reduce the impact of multipath interference on signals, improving signal quality and reliability. Their rotating electromagnetic waves can adapt to changes in propagation paths, providing more stable signal transmission. Furthermore, circularly polarized antennas can simultaneously receive and transmit linearly and circularly polarized signals, offering greater compatibility and expanding their application.

[0003] With the rapid development of fifth-generation mobile communications and future wireless communication systems, antenna performance requirements are increasing, including wideband, high gain, low profile, multi-band compatibility, and good radiation efficiency. By combining the advantages of spiral transmission structures and log-periodic antennas, differential feeding makes it easier to achieve circular polarization. The broadband characteristics of log-periodic antennas can easily expand antenna bandwidth to meet the broadband circular polarization requirements of satellite communications, radar systems, and other applications. Summary of the Invention

[0004] In view of the defects in the prior art, the purpose of the present invention is to provide a log-periodic antenna and device based on double-helix transmission loaded with rectangular patches.

[0005] According to the present invention, a logarithmic periodic antenna based on double-helix transmission loaded with a rectangular patch includes: a dielectric substrate;

[0006] A pair of metallized through holes are formed through the dielectric substrate, and a differential feeding port is provided at the bottom of each metallized through hole; a metal grounding layer is provided on the bottom surface of the dielectric substrate;

[0007] A pair of spiral transmission lines are arranged on the top surface of the dielectric substrate, one end of the spiral transmission line is connected to the top of the metallized through hole, and logarithmic periodic rectangular patches are distributed on the spiral transmission line.

[0008] Preferably, the differential feeding port is provided on the metal ground layer, the differential feeding port is a circular ring structure, the signal integration line points from the outer ring to the inner ring, and the initial phase difference between the two differential feeding ports is 180°, forming differential feeding.

[0009] Preferably, the metallized through hole is used to transmit the signal input from the lower differential feeding port to the upper spiral transmission line.

[0010] Preferably, it further comprises a metal disc;

[0011] The signal input end of the spiral transmission line is connected to a metal disk, and the metal disk covers the top opening of the metallized through hole.

[0012] Preferably, the area of ​​the metal disk is larger than the port area of ​​the signal input end of the spiral transmission line.

[0013] Preferably, the spiral transmission line is formed by cutting two quarter circles of different radii, and the forming steps include:

[0014] The center of the large circle is located at the origin of the coordinate system, and the center of the small circle is located at a certain distance from the origin along the +y axis;

[0015] The small circle is subtracted from the large circle, and the resulting structure is mirror-cropped about the y-axis. The initial position of the single spiral transmission line is translated to the coordinate origin.

[0016] Preferably, the logarithmic periodic rectangular patches are located on both sides of the spiral transmission line, and their length and width both conform to logarithmic periodic characteristics and vary according to a proportional factor.

[0017] Preferably, the dielectric substrate is located directly above the metal grounding layer, and the length and width of the dielectric substrate are consistent with those of the metal grounding layer, and the metal grounding layer is a rectangular grounding plate.

[0018] Preferably, the dielectric substrate is Rogers RT5880, with a relative dielectric constant of 2.2 and a dielectric loss tangent of 0.0009.

[0019] A mobile communication device provided by the present invention adopts the logarithmic periodic antenna based on double-helix transmission and loaded with rectangular patches.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention adopts the form of a double-helix transmission line and utilizes the spiral phase delay characteristics to naturally generate a 90° phase difference within a wide bandwidth. Combined with the radiation optimization of the logarithmic periodic rectangular patch, the axial ratio bandwidth can be improved.

[0022] 2. The present invention combines a log-periodic antenna with a double-helix transmission line and utilizes the characteristics of the log-periodic antenna to achieve electrical size scaling, thereby reducing the lateral size while maintaining performance, making it suitable for integrated and multi-band fusion design. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0024] Figure 1This is a structural diagram of a log-periodic antenna based on double-helix transmission loaded with rectangular patches proposed in one embodiment of the present invention.

[0025] Figure 2 A schematic top view of a log-periodic antenna based on double-helix transmission and loaded with rectangular patches proposed in one embodiment of the present invention.

[0026] Figure 3 A schematic side view of a log-periodic antenna based on double-helix transmission and loaded with rectangular patches, according to one embodiment of the present invention.

[0027] Figure 4 This is a bottom view of a log-periodic antenna based on double-helix transmission and loaded with rectangular patches, proposed in one embodiment of the present invention.

[0028] Figure 5 A schematic diagram of a formation process of a single spiral transmission line according to an embodiment of the present invention;

[0029] Figure 6 A schematic diagram of the size of a rectangular patch proposed in one embodiment of the present invention;

[0030] Figure 7 4 is a differential reflection coefficient curve of a log-periodic antenna in one embodiment of the present invention.

[0031] Figure 8 is an axial ratio curve of a log-periodic antenna in one embodiment of the present invention.

[0032] Figure 9 : is the radiation pattern of the antenna in one embodiment of the present invention at 23.2 GHz when Phi=0°.

[0033] Figure 10 : is the radiation pattern of the antenna in one embodiment of the present invention at 23.2 GHz when Phi=90°.

[0034] Description of reference numerals:

[0035] DETAILED DESCRIPTION

[0036] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0037] The present invention discloses a log-periodic antenna based on a double-helix transmission loaded with rectangular patches 2. Specifically, the log-periodic antenna comprises a dielectric substrate 5 having a pair of metallized through-holes 4 extending therethrough. Each of the metallized through-holes 4 has a differential feed port 6 at its bottom. A metal ground layer 7 is provided on the bottom surface of the dielectric substrate 5. A pair of spiral transmission lines 1 are provided on the top surface of the dielectric substrate 5, one end of each of the spiral transmission lines 1 being connected to the top of the metallized through-holes 4. Log-periodic rectangular patches 2 are distributed on the spiral transmission lines 1. The differential feed ports 6 on the bottom of the dielectric substrate 5 serve as the input for differential signals. The spiral transmission lines 1 and the log-periodic rectangular patches 2 on the top of the dielectric substrate 5 serve as radiating elements, radiating circularly polarized waves.

[0038] Reference Figures 1 to 4 , the structure and principle of each component are further described in detail below.

[0039] The logarithmic periodic rectangular patch 2 is a radiation unit, which is combined with the spiral transmission line 1 and is located directly above the dielectric substrate 5. It is differentially fed through the differential feeding port 6 at the bottom to radiate circularly polarized waves.

[0040] The forming process of a spiral transmission line is as follows: a single spiral line is formed by cutting two quarter circles of different radii. The steps for forming a single spiral transmission line are as follows:

[0041] (1) The center of the large circle is located at the coordinate origin, and the center of the small circle is formed by translating the origin along the +y axis by a certain distance. In a preferred embodiment, the translation distance is 1.5 mm.

[0042] (2) Subtract the small circle from the large circle, then mirror-cut the resulting structure about the y-axis, and translate the initial position of the single helix transmission line to the origin of the coordinate system. The specific formation process is shown in the attached figure. Figure 5 shown.

[0043] In a preferred embodiment, the spiral transmission line 1 is cut from two quarter circles with different radii, the radius of the smaller circle is 4 mm, and the radius of the larger circle is 6 mm.

[0044] Reference Figure 6 As shown, the logarithmic periodic rectangular patches 2 are located on both sides of the spiral transmission line 1. The length of the smallest logarithmic periodic rectangular patch 2 is 1.2 mm, the width is 0.4 mm, and the proportional factor k is 1.2, that is, the length of the second logarithmic periodic rectangular patch 2 is 1.2*1.2 mm, the width is 0.4*1.2 mm, the length of the third logarithmic periodic rectangular patch 2 is 1.2*1.2*1.2 mm, and the width is 0.4*1.2*1.2 mm. The lengths and widths of the remaining rectangular patches 2 increase proportionally in sequence.

[0045] Starting with the reference log-periodic rectangular patch 2, the remaining log-periodic rectangular patches 2 are distributed across the spiral transmission line, with the angular spacing between adjacent log-periodic rectangular patches 2 being 10°. The size of the log-periodic rectangular patches 2 varies according to the log-periodic antenna scale factor k. By differentially feeding the double-helix transmission line, circularly polarized waves are radiated outward through the log-periodic rectangular patches 2.

[0046] The signal input end of the spiral transmission line 1 is connected to a metal disk 3, which covers the top opening of the plated through-hole 4. The area of ​​the metal disk 3 is larger than the port area of ​​the signal input end of the spiral transmission line 1. The center of the metal disk 3 coincides with the plated through-hole 4 to fully receive the electromagnetic signal transmitted from below. The radius of the metal disk 3 is 0.4 mm.

[0047] The metallized through hole 4 is used to transmit the signal input from the differential feeding port 6 below to the spiral transmission line 1 above. The material used is copper, and the radius of the metallized through hole 4 is 0.2 mm.

[0048] The dielectric substrate 5 is located directly above the metal grounding layer 7, and its length and width are consistent with those of the metal grounding layer 7. The dielectric substrate 5 is made of Rogers 5880, with a relative dielectric constant of 2.2 and a loss tangent of 0.0009. Its specific dimensions are 20 mm × 20 mm × 2.5 mm. The metal grounding layer 7 is a rectangular grounding plate, measuring 20 mm × 20 mm.

[0049] The differential feed port 6 is provided on the metal ground layer 7 and is a circular ring structure with an inner diameter of 0.2 mm and an outer diameter of 0.3 mm. The signal integration line points from the outer ring to the inner ring, and the initial phase difference between the two differential feed ports 6 is 180°, forming differential feeding.

[0050] Conduct electromagnetic simulation test on the antenna with the above parameters. Figure 7 、 8 The electromagnetic simulation parameter curve of a log-periodic antenna based on a double-helix transmission loaded rectangular patch is shown. It can be seen that the differential reflection coefficient in the 22GHz-23.37GHz frequency band is less than -10dB, and the axial ratio in the 22.34GHz-23.52GHz band is less than 3dB.

[0051] Figure 9 Figure 3 is the radiation pattern of a circularly polarized common-aperture antenna based on a four-port annular patch and dumbbell medium at a frequency of 23.2 GHz and Phi = 0°. The black solid line represents right-hand polarization, and the black dotted line represents left-hand polarization. Figure 10Figure 3 is the radiation pattern of a circularly polarized common-aperture antenna based on a four-port annular patch and a dumbbell medium at a frequency of 31.2 GHz with Phi = 90°. The black solid line represents right-hand polarization, and the black dotted line represents left-hand polarization.

[0052] The spatial rectangular coordinate system O-XYZ is established, including the origin O, the X-axis, the Y-axis, and the Z-axis. The origin of the coordinate system is located at the center of the metal ground plane 7 in the figure. To prevent overlap between the coordinate system and components and interference with the drawing, the coordinate system is drawn outside the eight-arm Archimedean spiral circularly polarized dielectric resonator antenna. The dielectric radiator and the dielectric substrate 5 are both parallel to the XOY plane of the spatial rectangular coordinate system O-XYZ. The dielectric radiator is symmetrical about the origin.

[0053] The present invention also discloses a mobile communication device, which adopts the logarithmic periodic antenna based on double-helix transmission and loaded rectangular patch.

[0054] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply 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 this application.

[0055] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A log-periodic antenna based on a double-helix transmission loaded rectangular patch, characterized in that: include: a dielectric substrate (5); A pair of metallized through holes (4) are provided through the dielectric substrate (5), and a differential feed port (6) is provided at the bottom of each metallized through hole (4); a metal grounding layer (7) is provided on the bottom surface of the dielectric substrate (5); A pair of spiral transmission lines (1) are provided on the top surface of the dielectric substrate (5), one end of the spiral transmission line (1) is connected to the top of the metallized through hole (4), and logarithmic periodic rectangular patches (2) are distributed on the spiral transmission line (1).

2. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The differential feeding port (6) is arranged on a metal grounding layer (7), and the differential feeding port (6) is a circular ring structure, the signal integration line points from the outer ring to the inner ring, and the initial phase difference between the two differential feeding ports (6) is 180°, forming differential feeding.

3. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The metallized through hole (4) is used to transmit the signal input from the lower differential feeding port (6) to the upper spiral transmission line (1).

4. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: Also included is a metal disc (3); The signal input end of the spiral transmission line (1) is connected to a metal disk (3), and the metal disk (3) covers the top opening of the metallized through hole (4).

5. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 4, characterized in that: The area of ​​the metal disk (3) is larger than the port area of ​​the signal input end of the spiral transmission line (1).

6. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The spiral transmission line (1) is formed by cutting two quarter circles of different radii, and the forming steps include: The center of the large circle is located at the origin of the coordinate system, and the center of the small circle is located at a certain distance from the origin along the +y axis; The small circle is subtracted from the large circle, and the obtained structure is mirror-cut about the y-axis, and the initial position of the single spiral transmission line (1) is translated to the origin of the coordinate system.

7. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The logarithmic periodic rectangular patches (2) are located on both sides of the spiral transmission line (1), and their length and width both conform to the logarithmic periodic characteristics and change according to a proportional factor.

8. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The dielectric substrate (5) is located directly above the metal grounding layer (7), and the length and width of the dielectric substrate (5) are consistent with those of the metal grounding layer (7). The metal grounding layer (7) is a rectangular grounding plate.

9. The log-periodic antenna based on double-helix transmission loaded rectangular patch according to claim 1, characterized in that: The dielectric substrate (5) adopts Rogers RT5880, with a relative dielectric constant of 2.2 and a dielectric loss tangent of 0.0009.

10. A mobile communication device, characterized in that: A log-periodic antenna based on double-helix transmission loaded with rectangular patches according to any one of claims 1 to 9 is used.

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