3db power division bridge and coupled feed dual circularly polarized antenna unit

Abstract

The application provides a 3dB power division bridge and a coupled feeding dual circularly polarized antenna unit, the 3dB power division bridge comprises a first microstrip line and a second microstrip line, the first microstrip line and the second microstrip line both comprise an input feeding port, a λ / 4 overlapping coupling line, an equal phase line and a radiation port, the equal phase lines of the first microstrip line and the second microstrip line have the same wavelength; the first microstrip line and the second microstrip line are arranged in upper and lower two layers of PCB laminates, and after the arrangement is completed, the λ / 4 overlapping coupling lines of the first microstrip line and the second microstrip line overlap in the up-down direction. The 3dB power division bridge provided by the application is applied to the coupled feeding dual circularly polarized antenna unit, and can solve the problem that the design freedom of a traditional satellite terminal circularly polarized antenna is limited.

Description

Technical Field

[0001] This invention relates to the field of wireless communication antenna technology, and in particular to a 3dB power divider bridge and a coupled-fed dual circularly polarized antenna unit. Background Technology

[0002] In low-Earth orbit (LEO) satellite communications, the needs of vehicle-mounted, shipborne, and field emergency communication scenarios require satellite terminals to be miniaturized, lightweight, and portable. Furthermore, ground terminals must possess the ability to rapidly track high-speed moving satellites. Traditional mechanical parabolic antennas, due to their slow turning speed, cannot meet the real-time communication requirements of LEO satellites. In contrast, phased array antennas achieve millisecond-level electronic beam scanning and alignment through real-time amplitude and phase control of antenna elements, ensuring continuous high-performance communication.

[0003] Traditional Ku and Ka band satellite terminal circularly polarized phased array antennas are primarily fed using direct feeding (the feed conductor is directly electrically connected to the antenna radiating patch), and the 3dB power divider bridge in the feed network is typically figure-eight or figure-o'-shaped. Figure 1 As shown, this type of bridge occupies a large area in the PCB stack-up, which is detrimental to the layout and routing of SPI, CTRL, PWR, etc. in high-density PCBs. Furthermore, the direct feeding method requires the antenna radiating patch to be integrated into the PCB stack-up (the PCB stack-up between the antenna radiating patch and the power divider bridge is relatively thick, making it impossible to meet the requirements of symmetrical design), constraining the antenna design freedom, increasing the total thickness of the PCB stack-up and the risk of warpage, and requiring multiple lamination processes, thus increasing costs. Summary of the Invention

[0004] To address the problems existing in the prior art, a 3dB power divider bridge and coupled-fed dual circularly polarized antenna unit are provided to solve the problem of limited design freedom of traditional satellite terminal circularly polarized antennas.

[0005] The first aspect of this invention proposes a 3dB power divider bridge, comprising a first microstrip line and a second microstrip line. Both the first and second microstrip lines include an input feed port, a λ / 4 overlapping coupling line, an equiphase line, and a radiation port. The equiphase lines of the first and second microstrip lines have the same wavelength number. The first and second microstrip lines are respectively disposed in upper and lower PCB stack-up layers. After the arrangement is completed, the λ / 4 overlapping coupling lines of the first and second microstrip lines overlap in the vertical direction.

[0006] As a preferred embodiment, the coupling degree of the 3dB power divider bridge is controlled by adjusting its height between the upper and lower stacks and the overlap area of ​​the λ / 4 overlapping coupling lines.

[0007] As a preferred embodiment, the λ / 4 overlapping coupling line meets the design requirement of a 90° phase delay between the two signals in the synthesized circular polarization, and the first microstrip line and the second microstrip line have the same number of equiphase line wavelengths.

[0008] A second aspect of the present invention provides a coupled-fed dual circularly polarized antenna element, comprising, from top to bottom: an antenna parasitic patch, a first dielectric layer, an antenna radiating patch, a second dielectric layer, a coupling isolation layer, a third dielectric layer, a first microstrip line mounting layer, a fourth dielectric layer, a second microstrip line mounting layer, a fifth dielectric layer, an antenna feed microstrip line reference ground layer, a sixth dielectric layer, and a PCB stack-up reference ground layer; the coupling isolation layer is provided with a port isolation gap, a first feed coupling gap, and a second feed coupling gap; the first microstrip line mounting layer includes a first microstrip line and a first surrounding ground layer surrounding the first microstrip line; the second microstrip line mounting layer includes a second microstrip line and a second surrounding ground layer surrounding the second microstrip line. The system includes a ground plane; the first microstrip line and the second microstrip line form a 3dB power divider bridge; the radiation ports of the first microstrip line and the second microstrip line correspond vertically to the first feed coupling slot and the second feed coupling slot, respectively; multiple coaxial feed ground vias are arranged around the feed input ports of the first microstrip line and the second microstrip line, and the multiple coaxial feed ground vias are connected to the reference ground plane of the antenna feed microstrip line; a PCB stack-up ground via is also provided, and the PCB stack-up ground via connects the first ground plane, the second ground plane, the coupling isolation layer, the third dielectric layer, the fourth dielectric layer, the fifth dielectric layer, the reference ground plane of the antenna feed microstrip line, and the sixth dielectric layer and the PCB stack-up reference ground plane.

[0009] As a preferred embodiment, the port isolation gap is diagonally disposed in the coupling isolation layer to isolate the first power supply coupling gap and the second power supply coupling gap.

[0010] As a preferred embodiment, the port isolation gap is "I" or "T" shaped.

[0011] As a preferred embodiment, the first and second feed coupling gaps are U-shaped, and the feed coupling signals are 90° out of phase.

[0012] As a preferred embodiment, both the first microstrip line and the second microstrip line include an input feed port, a λ / 4 overlapping coupling line, an equiphase line, and a radiation port; the equiphase lines of the first microstrip line and the second microstrip line have the same wavelength number; and the λ / 4 overlapping coupling lines of the first microstrip line and the second microstrip line overlap in the vertical direction.

[0013] As a preferred embodiment, the coupling degree of the 3dB power divider bridge formed by the first microstrip line and the second microstrip line is controlled by adjusting the height between the upper and lower stacks and the overlap area of ​​the λ / 4 overlapping coupling lines.

[0014] As a preferred embodiment, the antenna parasitic patch, the first dielectric layer, the antenna radiating patch, and the second dielectric layer are stripped from the PCB and implemented in a separate design.

[0015] Compared with the prior art, the beneficial effects of adopting the above technical solution are as follows: The compact 3dB power divider bridge scheme proposed in this invention, combined with the coupled-fed dual circularly polarized antenna scheme, and further improved by the "I" or "T" type isolation slot, can meet the requirements of high-density PCB trace layout, improve the design freedom of satellite terminal circularly polarized antenna, and reduce the PCB design and manufacturing cost. Attached Figure Description

[0016] Figure 1 This is a 3dB bridge design scheme in the existing technology.

[0017] Figure 2 This is a schematic diagram of a compact 3dB power divider bridge proposed in an embodiment of the present invention.

[0018] Figure 3 This is an exploded view of a coupled-fed circularly polarized antenna element proposed in an embodiment of the present invention.

[0019] Figure 4 This is a perspective view of a coupled-fed circularly polarized antenna element proposed in an embodiment of the present invention. Detailed Implementation

[0020] The embodiments of this application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar modules or modules having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Rather, the embodiments of this application include all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0021] Example 1

[0022] To address the limited design freedom of traditional satellite terminal circularly polarized antennas, the current 3dB power divider bridge in the feed network is relatively large, which is not conducive to high-density PCB trace layout, and direct feeding requires an asymmetrical PCB stack-up design, increasing the risk of warpage. Therefore, this application proposes a compact 3dB power divider bridge.

[0023] Please refer to Figure 2This 3dB power divider bridge includes a first microstrip line and a second microstrip line. Both the first and second microstrip lines include an input feed port, a λ / 4 overlapping coupling line, an equiphase line, and a radiation port. The equiphase lines of the first and second microstrip lines have the same wavelength. In practical applications, the first and second microstrip lines are respectively placed in upper and lower PCB stack-up layers, with different orientations. After the first and second microstrip lines are set up, their λ / 4 overlapping coupling lines overlap vertically, while the remaining portions do not overlap.

[0024] In one embodiment, the coupling degree of the 3dB power divider bridge can be controlled by adjusting the height between the upper and lower stacks and the overlap area of ​​the λ / 4 overlapping coupling lines.

[0025] It should be noted that in this embodiment, the λ / 4 overlapping coupling line meets the design requirement of a 90° phase delay between the two signals in the synthesized circular polarization, and the first microstrip line and the second microstrip line have the same number of equiphase line wavelengths.

[0026] Example 2

[0027] Based on the compact 3dB power divider bridge proposed in Example 1, this example proposes a coupled-fed dual circularly polarized antenna unit. The compact 3dB power divider bridge is formed by the arrangement of microstrip lines inside, which can meet the requirements of high-density PCB trace layout and improve the design freedom of circularly polarized antennas for satellite terminals.

[0028] For details, please refer to Figure 3 , Figure 4 This coupled-fed dual-circularly polarized antenna unit includes, from top to bottom: an antenna parasitic patch 1, a first dielectric layer 2, an antenna radiating patch 3, a second dielectric layer 4, a coupling isolation layer 5, a third dielectric layer 6, a first microstrip line mounting layer 7, a fourth dielectric layer 8, a second microstrip line mounting layer 11, a fifth dielectric layer 12, an antenna feed microstrip line reference ground layer 13, a sixth dielectric layer 14, and a PCB stack-up reference ground layer 15. Each layer will be described in detail below.

[0029] (1) Antenna parasitic patch 1: Located on the top layer, it is excited by the radiation patch through near-field coupling and becomes a secondary radiation source.

[0030] (2) First dielectric layer 2: mainly serves to support the antenna parasitic patch 1.

[0031] (3) Antenna radiating patch 3: Directly connected to the feed network (microstrip line / coaxial probe) to convert radio frequency signals into electromagnetic radiation.

[0032] (4) Second dielectric layer 4: mainly serves to support the antenna radiating patch 3.

[0033] (5) Coupling isolation layer 5: This layer includes a port isolation gap 501, a first feed coupling gap 502, and a second feed coupling gap 503. The port isolation gaps are diagonally positioned within the coupling isolation layer to isolate the first feed coupling gap 502 and the second feed coupling gap 503, thereby improving the isolation between the left and right circularly polarized ports. In one embodiment, the port isolation gap is shaped like an "I" or a "T". In another embodiment, the first feed coupling gap 502 and the second feed coupling gap 503 are "U" shaped with openings facing different directions, allowing the coupled signals to have a 90-degree phase difference.

[0034] (6) Third dielectric layer 6: mainly serves to support the coupling isolation layer 5.

[0035] (7) First microstrip line layer 7: A first microstrip line 701 and a first surrounding ground 702 surrounding the first microstrip line are provided. The first microstrip line 701 includes an input feed port, a λ / 4 overlapping coupling line, an equal phase line and a radiation port, and the first surrounding ground 702 is provided around the first microstrip line 701.

[0036] (8) Fourth dielectric layer 8: mainly serves to support the first microstrip line setting layer 7.

[0037] (9) Second microstrip line layer 11: This layer contains a second microstrip line 1101 and a second ground plane 1102 surrounding the second microstrip line. The second microstrip line 1101 is identical to the first microstrip line 701, including an input feed port, λ / 4 overlapping coupling lines, equiphase lines, and a radiation port. The second ground plane 1102 surrounds the second microstrip line 1101. The arrangement of the first microstrip line 701 and the second microstrip line 1101 forms a compact 3dB power divider bridge structure. After the arrangement is completed, the λ / 4 overlapping coupling lines in the first microstrip line 701 and the second microstrip line 1101 have a certain overlap area in the vertical direction. The coupling degree of the 3dB power divider bridge is controlled by adjusting the height between the upper and lower layers and the area of ​​the overlapping region of the λ / 4 overlapping coupling lines. Meanwhile, the radiation ports of the first microstrip line 701 and the second microstrip line 1101 correspond to the first feed coupling slot 502 and the second feed coupling slot 503 in the vertical direction, respectively, to complete the feed coupling.

[0038] It should be further noted that in this stacked structure, a plurality of coaxial feed ground vias 9 are also provided, which respectively surround the input feed ports of the first microstrip line 701 and the second microstrip line 1101; the plurality of coaxial feed ground vias are connected to the reference ground layer 13 of the antenna feed microstrip line.

[0039] (10) Fifth dielectric layer 12: mainly serves to support the second microstrip line setting layer 11.

[0040] (11) Antenna feed microstrip line reference ground layer 13: mainly used to provide a reference ground for the microstrip line and to isolate the input feed port.

[0041] (12) Sixth dielectric layer 14: mainly serves to support the reference ground layer 13 of the antenna feed microstrip line.

[0042] (13) PCB stack-up reference ground layer 15: mainly used to provide a reference ground for the overall PCB stack-up structure. The first surrounding ground 702, the second surrounding ground 1102, the coupling isolation layer 5, the third dielectric layer 6, the fourth dielectric layer 8, the fifth dielectric layer 12, the antenna feed microstrip line reference ground layer 13, and the sixth dielectric layer 14 are connected to the PCB stack-up reference ground layer 15 by setting PCB stack-up ground via 10 in the stack-up structure.

[0043] In the coupled-fed circularly polarized antenna element proposed in this application, two feed signals can be coupled to the antenna radiating patch through "U"-shaped feed coupling slots with different orientations, and then radiated outwards. In one embodiment, the feed coupling slot can be set to other shapes to ensure that the width is consistent and the length is λ / 4.

[0044] To further reduce the thickness of the PCB stack-up structure, reduce processing difficulty, and improve reliability, in one embodiment, the four-layer structure consisting of the antenna parasitic patch 1, the first dielectric layer 2, the antenna radiating patch 3, and the second dielectric layer 4 is implemented by adopting an independent design method that peels off the PCB stack-up structure.

[0045] The coupled-fed dual circularly polarized antenna unit proposed in this invention can effectively improve port isolation to meet the requirements of high-density PCB trace layout, increase the design freedom of satellite terminal circularly polarized antennas, and reduce PCB design and manufacturing costs.

[0046] In other embodiments, based on the coupled-fed circularly polarized antenna elements proposed in the foregoing embodiments, multiple coupled-fed circularly polarized antenna elements can be combined to design a triangular, rectangular, or heterogeneous two-dimensional phased array antenna array layout.

[0047] For those skilled in the art, the specific meanings of the above terms in this invention can be understood according to the specific circumstances; the accompanying drawings in the embodiments are used to clearly and completely describe the technical solutions in the embodiments of this invention. Obviously, the described embodiments are some embodiments of this invention, but not all embodiments. Generally, the components of the embodiments of this invention described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0048] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A coupled-fed dual-circularly polarized antenna element, characterized in that, It includes, from top to bottom, an antenna parasitic patch, a first dielectric layer, an antenna radiating patch, a second dielectric layer, a coupling isolation layer, a third dielectric layer, a first microstrip line setting layer, a fourth dielectric layer, a second microstrip line setting layer, a fifth dielectric layer, an antenna feed microstrip line reference ground layer, a sixth dielectric layer, and a PCB stack-up reference ground layer; The coupling isolation layer is provided with a port isolation gap, a first power supply coupling gap, and a second power supply coupling gap; the first microstrip line layer includes a first microstrip line and a first ground plane surrounding the first microstrip line; The second microstrip line layer includes a second microstrip line and a second ground surrounding the second microstrip line; the first microstrip line and the second microstrip line form a 3dB power divider bridge; The radiation ports of the first microstrip line and the second microstrip line correspond to the positions of the first feed coupling slot and the second feed coupling slot in the vertical direction, respectively. The first and second microstrip lines are surrounded by a plurality of coaxial feed ground vias, which are connected to the reference ground layer of the antenna feed microstrip line; a PCB stack-up ground via is also provided, which connects the first surrounding ground, the second surrounding ground, the coupling isolation layer, the third dielectric layer, the fourth dielectric layer, the fifth dielectric layer, the reference ground layer of the antenna feed microstrip line, and the sixth dielectric layer to the PCB stack-up reference ground layer; Both the first and second microstrip lines include an input feed port, a λ / 4 overlapping coupling line, an equiphase line, and a radiation port; the equiphase lines of the first and second microstrip lines have the same wavelength number; and the λ / 4 overlapping coupling lines of the first and second microstrip lines overlap in the vertical direction.

2. The coupled-fed dual-circularly polarized antenna element according to claim 1, characterized in that, The port isolation gap is diagonally located in the coupling isolation layer to isolate the first power supply coupling gap and the second power supply coupling gap.

3. The coupled-fed dual-circularly polarized antenna element according to claim 1 or 2, characterized in that, The port isolation gap is "I" or "T" shaped.

4. The coupled-fed dual-circularly polarized antenna element according to claim 1, characterized in that, The first and second feed coupling gaps are U-shaped, and the feed coupling signals are 90° out of phase.

5. The coupled-fed dual-circularly polarized antenna element according to claim 1, characterized in that, The coupling degree of the 3dB power divider bridge formed by the first microstrip line and the second microstrip line is controlled by adjusting the height between the upper and lower stacks and the overlap area of ​​the λ / 4 overlapping coupling lines.

6. The coupled-fed dual-circularly polarized antenna element according to claim 1, characterized in that, The antenna parasitic patch, the first dielectric layer, the antenna radiating patch, and the second dielectric layer are stripped from the PCB and implemented in a separate design.

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