A Ku-band small broadband high-isolation satellite communication tri-polarized unit and array antenna thereof

Abstract

A Ku-band small wideband high-isolation satellite communication tri-polarization unit, comprising a horizontal dual-polarization radiation substrate, a dielectric support plate and a ground plate arranged from top to bottom, a radio frequency joint-coupling patch combined feed structure and a vertical polarization antenna structure are arranged between the horizontal dual-polarization radiation substrate and the ground plate and vertically penetrate the dielectric support plate; a Ku-band small wideband high-isolation satellite communication tri-polarization array antenna based on the tri-polarization unit, comprising n*n array arranged Ku-band small wideband high-isolation satellite communication tri-polarization units, and the spacing between the centers of adjacent units is greater than the length dimension of the unit; the three orthogonal polarizations in the tri-polarization antenna are used to obtain higher degrees of freedom, thereby enhancing the channel capacity and anti-weakness ability of the communication system, and meanwhile, the wideband, high-isolation, small-size and other characteristics of the antenna are realized to improve the comprehensive performance of the satellite communication system.

Description

Technical Field

[0001] This invention belongs to the field of satellite communication technology, specifically relating to a small broadband high-isolation satellite communication tripolar unit and its array antenna in the Ku band. Background Technology

[0002] Satellite communication systems not only need to achieve communication between satellites, but also need to track various mobile carriers such as vehicles, ships, and aircraft in real time, transmitting data information in complex, dynamically moving electromagnetic environments. To meet these application requirements, satellite communication systems need large channel and communication capacities, strong resistance to fading and interference, and high detection and tracking accuracy, while miniaturizing and lightweighting communication components as much as possible. Therefore, as a key communication component, satellite communication antennas should possess characteristics such as wider operating bandwidth, good impedance matching, and higher isolation, while also being miniaturized, multi-polarized, and resistant to multipath fading. However, the main problem with current satellite communication antennas is that most are single-polarized or dual-polarized antennas, with very limited channel capacity and fading resistance, and various antenna performance characteristics cannot be simultaneously achieved.

[0003] To increase the channel capacity and multipath fading resistance of satellite communication systems, MIMO technology is commonly used. Traditional MIMO employs spatial diversity, requiring multiple single-polarized antennas that must be spaced sufficiently apart to operate independently. This approach not only wastes significant space resources on the satellite but also increases its weight. Polarization diversity, on the other hand, utilizes the orthogonal nature of multiple polarizations, enabling simultaneous operation of multiple polarizations on a single antenna. Compared to spatial diversity, polarization diversity achieves the same performance while reducing the number of antennas by a factor of two, thus saving considerable space.

[0004] Currently, most antennas constructed using polarization diversity technology are dual-polarized antennas. Compared to single-polarized antennas, their resistance to fading and channel capacity can be increased several times over, but the limitations remain. Tri-polarized antennas, compared to dual-polarized antennas, have higher degrees of freedom and a more significant effect in increasing channel capacity and resistance to fading. Furthermore, when satellites use phased arrays for positioning and tracking, combined with beamforming algorithms, tri-polarized phased arrays have higher scanning gain than dual-polarized phased arrays during scanning, enabling satellites to achieve higher positioning and tracking accuracy. However, there is currently no research on tri-polarized antennas for satellite communication. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, the present invention aims to propose a small, broadband, high-isolation satellite communication tripolar unit and its array antenna in the Ku band. By utilizing the three orthogonal polarizations in the tripolar antenna, higher degrees of freedom can be obtained, thereby enhancing the channel capacity and anti-fading capability of the communication system. At the same time, by realizing the wide bandwidth, high isolation, and miniaturization characteristics of the antenna, the overall performance of the satellite communication system can be improved.

[0006] To achieve the above objectives, the technical means employed in this invention are as follows:

[0007] A small broadband high-isolation satellite communication tripolar unit in the Ku band includes a horizontal dual-polarized radiating substrate 2, a dielectric support plate 5, and a ground plane 7 arranged from top to bottom. The horizontal dual-polarized radiating substrate 2 and the ground plane 7 are respectively connected by a radio frequency connector-coupled patch combined feed structure 4 and a vertically polarized antenna structure 6 that are vertically inserted into the dielectric support plate 5.

[0008] Arc-shaped V-shaped parasitic patch strips 1 are printed on the upper surface of the horizontal dual-polarized radiation substrate 2, along the four quadrant axes of the horizontal dual-polarized radiation substrate 2, and near the center of the four sides of the horizontal dual-polarized radiation substrate 2, respectively. 90° sector-shaped horizontal half-wave oscillators 3 are printed on the lower surface of the horizontal dual-polarized radiation substrate 2 and in the four quadrants of the horizontal dual-polarized radiation substrate 2, respectively. The tails of two adjacent 90° sector-shaped horizontal half-wave oscillators 3 are respectively provided with a first circular hole 301 and a second circular hole 302. The horizontal dual-polarized radiation substrate 2 is respectively provided with a first power supply through hole 303 corresponding to the first circular hole 301 and a second power supply through hole 304 corresponding to the second circular hole 302.

[0009] The RF connector-coupled patch combined feeding structure 4 includes a direct-connection Y-shaped coupling patch 402 and a connecting Y-shaped coupling patch 407 orthogonally printed on the upper surface of the horizontal dual-polarized radiating substrate 2 between intersecting quadrants. The direct-connection Y-shaped coupling patch 402 has a third circular hole 408 at its tail end, and the connecting Y-shaped coupling patch 407 has a fourth circular hole 409 at its tail end. One end of the inner core 401 of the first horizontally polarized RF connector is connected to the upper surface of the horizontal dual-polarized radiating substrate 2, and the other end passes through the third circular hole 409. 08. The first feed through hole 303, the first circular hole 301, the dielectric support plate 5 and the ground plane 7 are connected to the outer conductor 411 of the first horizontally polarized RF connector to form feed port one. One end of the inner core 410 of the second horizontally polarized RF connector is connected to the upper surface of the horizontal dual-polarized radiation substrate 2, and the other end passes through the fourth circular hole 409, the second feed through hole 304, the second circular hole 302, the dielectric support plate 5 and the ground plane 7 respectively, and is connected to the outer conductor 412 of the second horizontally polarized RF connector to form feed port two.

[0010] The RF connector-coupled patch combined power supply structure 4 also includes multiple metal short-circuit posts 403 equivalent to coaxial line outer conductors and multiple metal short-circuit posts 404 serving as short-circuit baluns, which are connected between the horizontal dual-polarized radiating substrate 2 and the ground plane 7 around the center of the dielectric support plate 5. The multiple metal short-circuit posts 403 equivalent to coaxial line outer conductors, the multiple short-circuit balun metal short-circuit posts 404, and the inner core 401 of the first horizontally polarized RF connector and the inner core 410 of the second horizontally polarized RF connector are distributed at equal angles and intervals within the dielectric support plate 5.

[0011] The connecting Y-shaped coupling patch 407 is disconnected at the intersection with the direct Y-shaped coupling patch 402, and the two disconnected parts are connected by metal through holes 405 correspondingly provided on the horizontal dual-polarized radiation substrate 2 and rectangular strips 406 printed on the lower surface of the horizontal dual-polarized radiation substrate 2.

[0012] The number of the multiple metal short-circuit posts 403, which are equivalent to the outer conductors of the coaxial line, and the number of the multiple short-circuit balun metal short-circuit posts 404 are both 4.

[0013] The vertically polarized antenna structure 6 includes a 1-to-4 equal power microstrip line 602 printed on the upper surface of the ground plane 7. The 1-to-4 equal power microstrip line 602 has a 50Ω central circular node 606 in the middle. At the ends of the 1-to-4 equal power microstrip line 602, there are end circular nodes 603. Vertical metal pillars 601 are respectively set on the end circular nodes 603. The top of the vertical metal pillars 601 penetrates the dielectric support plate 5. The 50Ω central circular node 606 is connected to the end circular nodes 603 by a quarter impedance transformation line 607. The 50Ω central circular node 606 is connected to one end of the inner core of the vertically polarized RF connector 604. The other end of the inner core of the vertically polarized RF connector 604 passes through the ground plane 7 and is connected to the outer conductor 605 of the vertically polarized RF connector to form the third feed port.

[0014] The lower surface of the ground plane 7 is printed with a ground plane 706. The top surfaces of the outer conductors 411 of the first horizontally polarized RF connector, the outer conductors 412 of the second horizontally polarized RF connector, and the outer conductors 605 of the vertically polarized RF connector are all in contact with the ground plane 706. The ground plane 7 has inner core through holes 701 and 702 of the first horizontally polarized RF connector that are adapted to the inner cores 401 and 410 of the first and second horizontally polarized RF connectors, respectively; a coaxial outer conductor metal post through hole 703 that is adapted to the metal shorting post 403 equivalent to the coaxial outer conductor; a shorting balun metal post through hole 704 that is adapted to the shorting balun metal shorting post 404; and a vertically polarized RF connector inner core through hole 705 that is adapted to the inner core of the vertically polarized RF connector 604.

[0015] The included angle of the arc-shaped V-shaped parasitic patch strip 1 is 121.3 ± 10 degrees.

[0016] A small, broadband, high-isolation satellite communication tri-polarized array antenna in the Ku band includes n×n arrayed small, broadband, high-isolation satellite communication tri-polarized units in the Ku band, with the spacing between the centers of adjacent units greater than the unit length. Each small, broadband, high-isolation satellite communication tri-polarized unit in the Ku band includes a horizontally dual-polarized radiating substrate 2, a dielectric support plate 5, and a ground plane 7 arranged from top to bottom. A radio frequency connector-coupled patch combined feed structure 4 and a vertically polarized antenna structure 6 are respectively arranged between the horizontally dual-polarized radiating substrate 2 and the ground plane 7, which are vertically inserted into the dielectric support plate 5. The entire array antenna shares a single horizontally dual-polarized radiating substrate 2, a single dielectric support plate 5, and a single ground plane 7.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] In this invention, the inner core 401 of the first horizontally polarized RF connector, the outer conductor 411 of the first horizontally polarized RF connector (or the inner core 410 and the outer conductor 412 of the second horizontally polarized RF connector), the direct-connection Y-shaped coupling patch 402 (or the connecting Y-shaped coupling patch 407), two metal short-circuit posts 403 equivalent to coaxial line outer conductors, and two short-circuit balun metal short-circuit posts 404 together form a 90° sector-shaped ring horizontal half-wave oscillator 3 feeding structure; the inner core of the horizontally dual-polarized RF connector (the inner core of the first horizontally polarized RF connector) The inner core 401 (or the inner core 410 of the second horizontally polarized RF connector) and the metal short-circuit post 403, which is equivalent to the outer conductor of the coaxial line, function as a traditional coaxial line, but the structure is simpler and easier to process and solder in small-sized antenna structures. In addition, by changing the spacing between the inner core 401 of the first horizontally polarized RF connector and the corresponding metal short-circuit post 403, or the spacing between the inner core 410 of the second horizontally polarized RF connector and the corresponding metal short-circuit post 403, the antenna impedance can be adjusted to achieve good impedance matching.

[0019] The Y-shaped coupling patch (direct-connected Y-shaped coupling patch 402 or connecting Y-shaped coupling patch 407) of the RF connector-coupled patch combined feeding structure can be used for coupling feeding, which can widen the operating frequency band of the horizontal dual-polarized antenna. Furthermore, by appropriately adjusting the size of the Y-shaped coupling patch, the isolation between the two 90° sector ring horizontal half-wave dipoles 3 can be improved. The short-circuit balun metal short-circuit post 404 is connected to one arm of the 90° sector ring horizontal half-wave dipole 3 without a circular hole, serving as the antenna balun and giving the antenna more stable characteristics.

[0020] In addition to the use of Y-shaped patch coupling patch, the loading of arc-shaped V-shaped parasitic patch strip 1 also strengthens the mutual influence between the two 90° sector-shaped horizontal half-wave dipoles 3, thereby introducing a new resonant point and further widening the antenna's operating frequency band. Furthermore, the horizontal dual-polarized antenna radiator is composed of 90° sector-shaped horizontal half-wave dipoles 3 obtained by hollowing out two pairs of quarter-circular patches. The hollowing out process can extend the current path and realize the miniaturization of the antenna.

[0021] The radiator of the vertically polarized antenna structure 6 consists of four vertical metal pillars 601, which are embedded in the support plate 5 and fed in phase and with equal amplitude by a one-to-four equal power distribution microstrip line 602. The quarter-impedance transformation line 607 in the one-to-four equal power distribution microstrip line 602 can achieve good impedance matching. When the four vertical metal pillars 601 are working, they are equivalent to a thick monopole with a radius equal to the length of the impedance transformation line 607, which has a larger characteristic impedance, thus making the input impedance of the vertically polarized antenna change more smoothly with frequency. At the same time, there is a certain coupling between the four vertical metal pillars 601. By appropriately adjusting their spacing, new resonances can be introduced, thereby realizing the wideband characteristics of vertical polarization. The four vertical metal pillars 601 are placed around the two 90° sector-shaped horizontal half-wave dipoles 3 along the four quadrant axes of the horizontal dual-polarized radiating substrate 2. This layout is conducive to achieving high isolation between the one-to-four equal power distribution microstrip line 602 and the 90° sector-shaped horizontal half-wave dipoles 3.

[0022] In summary, the use of the RF connector-coupled patch combination structure 4 and the one-to-four equal power microstrip line 602 simplifies the construction of the Ku-band satellite communication tri-polarized antenna. The constructed tri-polarized antenna can increase the channel capacity and anti-multipath fading capability of satellite communication. The loading of the Y-shaped patch coupling patch (direct-connected Y-shaped coupling patch 402 or connecting Y-shaped coupling patch 407) and the arc-shaped V-shaped parasitic patch strip 1 realizes the wideband characteristics of the horizontal dual-polarized antenna. The simultaneous operation of the four vertical metal pillars 601 realizes the equivalent monopole characteristics and the function of the quarter-impedance transformation line 607, realizing the wideband characteristics and good impedance matching of the vertical polarized antenna structure 6. The relative bandwidth shared by the three polarizations of the antenna can reach 24%, thereby expanding the communication capacity of the satellite communication system. The hollowing out of the horizontal dual-polarized radiator realizes the miniaturization of the antenna, reducing the lateral dimension of the antenna to 0.47λ (corresponding to the center frequency), which can save more satellite space resources. The structural layout of placing four vertical metal pillars 601 around two 90° sector-shaped horizontal half-wave oscillators 3, along with its highly symmetrical structural features, results in a port isolation greater than 29.2 dB between the three polarizations and a cross-polarization isolation of 32 dB (as shown in the results figure). Figures 12-22As can be seen, this enhances the anti-interference capability of the satellite communication system. Therefore, the small broadband high-isolation satellite communication tri-polarization unit and its array antenna in the Ku band involved in this invention have strong practical application value in increasing the channel capacity and resistance to fading of the satellite communication system, improving the overall system performance, and realizing high-performance satellite communication. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the antenna of the present invention;

[0024] Figure 2 This is a top view of the antenna of the present invention;

[0025] Figure 3 This is a side view of the antenna of the present invention;

[0026] Figure 4 This is a bottom view of the antenna of the present invention;

[0027] Figure 5 This is a top view of the arc-shaped V-shaped parasitic patch strip in the antenna of the present invention;

[0028] Figure 6 This is a top view of the 90° sector-shaped ring horizontal half-wave dipole in the antenna of this invention;

[0029] Figure 7 This is a side view of the horizontally dual-polarized radiating substrate in the antenna of the present invention;

[0030] Figure 8 This is a side view of the combined RF connector-coupled patch feeding structure in the antenna of the present invention;

[0031] Figure 9 This is a structural diagram of the vertically polarized antenna in the antenna of this invention;

[0032] Figure 10 This is a side view of the ground plane in the antenna of the present invention;

[0033] Figure 11 This is a structural diagram of the 4×4 satellite communication tripolar array antenna in the antenna of this invention;

[0034] Figure 12 This is a voltage standing wave ratio (VSWR) curve of the three ports of the antenna of this invention;

[0035] Figure 13 This is a curve showing the coupling coefficient between the three ports of the antenna of this invention;

[0036] Figure 14 This is the D-plane radiation pattern of the antenna feed port of the present invention at 11.75 GHz;

[0037] Figure 15 This is the D-plane radiation pattern of the antenna feed port of the present invention at 13GHz;

[0038] Figure 16 This is the D-plane radiation pattern of the antenna feed port of the present invention at 14.5 GHz;

[0039] Figure 17 This is the D-plane radiation pattern of the antenna feed port two of the present invention at 11.75 GHz;

[0040] Figure 18 This is the D-plane radiation pattern of the antenna feed port two of the present invention at 13GHz;

[0041] Figure 19 This is the D-plane radiation pattern of the antenna feed port two of the present invention at 14.5 GHz;

[0042] Figure 20 This is the D-plane radiation pattern of the antenna feed port three of the present invention at 11.75 GHz;

[0043] Figure 21 This is the D-plane radiation pattern of the antenna feed port three of the present invention at 13GHz;

[0044] Figure 22 This is the D-plane radiation pattern of the antenna feed port three of the present invention at 14.5 GHz.

[0045] In the figure: 1. Arc-shaped V-shaped parasitic patch strip; 2. Horizontal dual-polarized radiating substrate; 3. 90° sector-shaped ring horizontal half-wave dipole; 4. RF connector-coupled patch combined feed structure; 5. Dielectric support plate; 6. Vertically polarized antenna structure; 7. Ground plane; 301. First circular hole; 302. Second circular hole; 303. First feed through hole; 304. Second feed through hole; 401. Inner core of the first horizontally polarized RF connector; 402. Direct-connection Y-shaped coupling patch; 403. Metal short-circuit post equivalent to the outer conductor of the coaxial line; 404. Short-circuit balun metal short-circuit post; 405. Metal through hole; 406. Rectangular strip; 407. Connecting Y-shaped coupling patch; 408. Third circular hole; 409. Fourth circular hole; 41. 0. Inner core of the second horizontally polarized RF connector; 411. Outer conductor of the first horizontally polarized RF connector; 412. Outer conductor of the second horizontally polarized RF connector; 601. Vertical metal pillar; 602. One-to-four equal power distribution microstrip line; 603. End circular node; 604. Vertically polarized RF connector; 605. Outer conductor of the vertically polarized RF connector; 606. 50Ω center circular node; 607. Quarter impedance transformation line; 701. Inner core through-hole of the first horizontally polarized RF connector; 702. Inner core through-hole of the second horizontally polarized RF connector; 703. Equivalent coaxial line outer conductor metal pillar through-hole; 704. Short-circuit balun metal pillar through-hole; 705. Inner core through-hole of the vertically polarized RF connector; 706. Ground plane. Detailed Implementation

[0046] The present invention will now be described in detail with reference to the accompanying drawings.

[0047] See Figure 1 A small broadband high-isolation satellite communication tripolar unit in the Ku band includes a horizontal dual-polarized radiating substrate 2, a dielectric support plate 5, and a ground plane 7 arranged from top to bottom. The horizontal dual-polarized radiating substrate 2 and the ground plane 7 are respectively connected by a radio frequency connector-coupled patch combined feed structure 4 and a vertically polarized antenna structure 6 that are vertically inserted into the dielectric support plate 5.

[0048] See Figure 1 , Figure 6 , Figure 7 Arc-shaped V-shaped parasitic patch strips 1 are printed on the upper surface of the horizontal dual-polarized radiation substrate 2, along the four quadrant axes of the horizontal dual-polarized radiation substrate 2, and near the center of the four sides of the horizontal dual-polarized radiation substrate 2, respectively. 90° sector-shaped horizontal half-wave oscillators 3 are printed on the lower surface of the horizontal dual-polarized radiation substrate 2 and in the four quadrants of the horizontal dual-polarized radiation substrate 2, respectively. The tails of two adjacent 90° sector-shaped horizontal half-wave oscillators 3 are respectively provided with a first circular hole 301 and a second circular hole 302. The horizontal dual-polarized radiation substrate 2 is respectively provided with a first power supply through hole 303 corresponding to the first circular hole 301 and a second power supply through hole 304 corresponding to the second circular hole 302.

[0049] See Figures 1 to 3 , Figure 8 The RF connector-coupled patch combined feeding structure 4 includes a direct-connection Y-shaped coupling patch 402 and a connecting Y-shaped coupling patch 407 orthogonally printed on the upper surface of the horizontal dual-polarized radiating substrate 2 between intersecting quadrants. The direct-connection Y-shaped coupling patch 402 has a third circular hole 408 at its tail end, and the connecting Y-shaped coupling patch 407 has a fourth circular hole 409 at its tail end. One end of the inner core 401 of the first horizontally polarized RF connector is connected to the upper surface of the horizontal dual-polarized radiating substrate 2, and the other end passes through the third circular hole. 408. The first feed through hole 303, the first circular hole 301, the dielectric support plate 5 and the ground plane 7 are connected to the outer conductor 411 of the first horizontally polarized RF connector to form feed port one. One end of the inner core 410 of the second horizontally polarized RF connector is connected to the upper surface of the horizontal dual-polarized radiation substrate 2, and the other end passes through the fourth circular hole 409, the second feed through hole 304, the second circular hole 302, the dielectric support plate 5 and the ground plane 7 respectively, and is connected to the outer conductor 412 of the second horizontally polarized RF connector to form feed port two.

[0050] The RF connector-coupled patch combined power supply structure 4 also includes multiple metal short-circuit posts 403 equivalent to coaxial line outer conductors and multiple metal short-circuit posts 404 serving as short-circuit baluns, which are connected between the horizontal dual-polarized radiating substrate 2 and the ground plane 7 around the center of the dielectric support plate 5. The multiple metal short-circuit posts 403 equivalent to coaxial line outer conductors, the multiple short-circuit balun metal short-circuit posts 404, and the inner core 401 of the first horizontally polarized RF connector and the inner core 410 of the second horizontally polarized RF connector are distributed at equal angles and intervals within the dielectric support plate 5.

[0051] See Figure 8 The connecting Y-shaped coupling patch 407 is disconnected at the intersection with the direct-connecting Y-shaped coupling patch 402, and the two disconnected parts are connected by metal through holes 405 correspondingly provided on the horizontal dual-polarized radiation substrate 2 and rectangular strips 406 printed on the lower surface of the horizontal dual-polarized radiation substrate 2.

[0052] The number of the multiple metal short-circuit posts 403, which are equivalent to the outer conductors of the coaxial line, and the number of the multiple short-circuit balun metal short-circuit posts 404 are both 4.

[0053] See Figure 9 The vertically polarized antenna structure 6 includes a 1-to-4 equal power microstrip line 602 printed on the upper surface of the ground plane 7. The 1-to-4 equal power microstrip line 602 has a 50Ω central circular node 606 in the middle. At the ends of the 1-to-4 equal power microstrip line 602, there are end circular nodes 603. Vertical metal pillars 601 are respectively set on the end circular nodes 603. The top of the vertical metal pillars 601 penetrates the dielectric support plate 5. The 50Ω central circular node 606 is connected to the end circular nodes 603 by a quarter impedance transformation line 607. The 50Ω central circular node 606 is connected to one end of the inner core of the vertically polarized RF connector 604. The other end of the inner core of the vertically polarized RF connector 604 passes through the ground plane 7 and is connected to the outer conductor 605 of the vertically polarized RF connector to form the third feed port.

[0054] See Figure 3 , Figures 8 to 10The lower surface of the ground plane 7 is printed with a ground plane 706. The top surfaces of the outer conductors 411 of the first horizontally polarized RF connector, the outer conductors 412 of the second horizontally polarized RF connector, and the outer conductors 605 of the vertically polarized RF connector are all in contact with the ground plane 706. The ground plane 7 has inner core through holes 701 and 702 of the first horizontally polarized RF connector that are adapted to the inner cores 401 and 410 of the first and second horizontally polarized RF connectors, respectively; a coaxial outer conductor metal post through hole 703 that is adapted to the metal shorting post 403 equivalent to the coaxial outer conductor; a shorting balun metal post through hole 704 that is adapted to the shorting balun metal shorting post 404; and a vertically polarized RF connector inner core through hole 705 that is adapted to the inner core of the vertically polarized RF connector 604.

[0055] See Figure 5 The included angle of the arc-shaped V-shaped parasitic patch strip 1 is 121.3 ± 10 degrees.

[0056] See Figure 11 A small, broadband, high-isolation satellite communication tri-polarized array antenna in the Ku band includes n×n arrayed small, broadband, high-isolation satellite communication tri-polarized units in the Ku band, with the spacing between the centers of adjacent units greater than the unit length. Each small, broadband, high-isolation satellite communication tri-polarized unit in the Ku band includes a horizontally dual-polarized radiating substrate 2, a dielectric support plate 5, and a ground plane 7 arranged from top to bottom. A radio frequency connector-coupled patch combined feed structure 4 and a vertically polarized antenna structure 6 are respectively arranged between the horizontally dual-polarized radiating substrate 2 and the ground plane 7, which are vertically inserted into the dielectric support plate 5. The entire array antenna shares a single horizontally dual-polarized radiating substrate 2, a single dielectric support plate 5, and a single ground plane 7.

[0057] By employing multiple technologies, the Ku-band satellite communication tri-polarized antenna element and its array in this invention were constructed. Wideband impedance characteristics were achieved within a small size, and the antenna maintains high port isolation and cross-polarization isolation among its three polarizations within a compact structure, enabling the three polarizations to operate independently. This invention not only increases the channel capacity and anti-fading capability of satellite communication systems, but its excellent port and radiation characteristics also contribute to improving the overall performance of satellite communication systems, thereby achieving high-performance communication.

[0058] 1. Simulation Content

[0059] Simulation experiments were conducted on the antenna of the above embodiment using simulation software. The voltage standing wave ratio, port isolation, and radiation pattern of the antenna are shown below. Figures 12 to 22 .

[0060] 2. Simulation Results

[0061] Figure 12 The figure shows the voltage standing wave ratio (VSWR) as a function of operating frequency, obtained from the simulation of the antenna in the embodiment. When the VSWR is less than 2, all three ports of the antenna, namely feed port one, feed port two, and feed port three, can operate in the Ku band of 11.46 GHz to 14.86 GHz, with a relative bandwidth of up to 25.8%. This result demonstrates that the antenna of the present invention has achieved significant broadband characteristics.

[0062] Figure 13 The curve shows the three-port isolation as a function of operating frequency, obtained from the simulation of the antenna in the embodiment. The overall isolation between the three ports is greater than 26.59 dB across the entire operating frequency band. This result demonstrates that the three polarizations of the antenna of the present invention exhibit good independence.

[0063] Figures 14-22 The antenna simulation results for the three ports are shown in plane D (the vertical plane where the angle bisector of the angle between the direct-connected Y-coupled patch 402 and the connecting Y-coupled patch 407 is located). Throughout the entire frequency band, the horizontally polarized beam (the pattern beam generated when excited by feed port one or feed port two) points towards the 0° elevation angle, with a maximum gain range of 5.78dB to 8.26dB, and a cross-polarization isolation (XPD) of 30.4dB at the beam pointing direction (0° direction). The vertically polarized beam (the pattern beam generated when excited by feed port three) points towards the approximately 40° elevation angle throughout the entire frequency band, with a maximum gain range of 2.68dB to 4.88dB, and a cross-polarization isolation (XPD) of 46dB at the beam pointing direction (40° direction). These results demonstrate that the antenna of this invention possesses high cross-polarization isolation and stable gain characteristics.

[0064] The use of the RF connector-coupled patch combination structure 4 and the one-to-four equal power microstrip line 602 in this invention simplifies the construction of the Ku-band satellite communication tri-polarized antenna. The constructed tri-polarized antenna can increase the channel capacity of satellite communication and its resistance to multipath fading. The loading of the Y-shaped patch coupling patch (direct-connected Y-shaped coupling patch 402 or connecting Y-shaped coupling patch 407) and the arc-shaped V-shaped parasitic patch strip 1 realizes the wideband characteristics of the horizontal dual-polarized antenna. The equivalent monopole characteristics when the four vertical metal pillars 601 work simultaneously and the function of the quarter-impedance transformation line 607 realize the wideband characteristics and good impedance matching of the vertical polarized antenna structure 6, so that the relative bandwidth shared by the three polarizations of the antenna can reach 24%, thereby expanding the communication capacity of the satellite communication system. The hollowing out of the horizontal dual-polarized radiator realizes the miniaturization of the antenna, reducing the lateral dimension of the antenna to 0.47λ (corresponding to the center frequency), which can save more satellite space resources. The structural layout of placing four vertical metal pillars 601 around two 90° sector-shaped horizontal half-wave oscillators 3, along with its highly symmetrical structural features, results in a port isolation greater than 29.2 dB between the three polarizations and a cross-polarization isolation of 32 dB (as shown in the results figure). Figures 12-22 (As can be seen), this enhances the anti-interference capability of the satellite communication system.

[0065] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Obviously, under the concept of the present invention, the structure, parameters and frequency of the present invention can be modified to obtain the broadband characteristics and high isolation characteristics (including high port isolation and cross-polarization isolation) of the antenna of the present invention, as well as to realize the modularity and arraying of the antenna, but these are all within the scope of protection of the present invention.

Claims

1. A small, broadband, high-isolation satellite communication tripolar unit in the Ku band, comprising a horizontally dual-polarized radiating substrate (2), a dielectric support plate (5), and a ground plane (7) arranged from top to bottom, characterized in that: The horizontal dual-polarized radiating substrate (2) and the ground plane (7) are respectively provided with a radio frequency connector-coupled patch combined feeding structure (4) and a vertical polarized antenna structure (6) that penetrate the dielectric support plate (5). On the upper surface of the horizontal dual-polarized radiation substrate (2), along the four quadrant axes of the horizontal dual-polarized radiation substrate (2), and near the center of the four sides of the horizontal dual-polarized radiation substrate (2), arc-shaped V-shaped parasitic patch strips (1) are printed respectively. The V-shaped included angle of the arc-shaped V-shaped parasitic patch strips (1) is 121.3±10 degrees. On the lower surface of the horizontal dual-polarized radiation substrate (2), and in the four quadrants of the horizontal dual-polarized radiation substrate (2), 90° sector-shaped ring horizontal half-wave oscillators (3) are printed respectively. Among them, the tail of two adjacent 90° sector-shaped ring horizontal half-wave oscillators (3) are respectively provided with a first circular hole (301) and a second circular hole (302). The horizontal dual-polarized radiation substrate (2) is respectively provided with a first power supply through hole (303) corresponding to the first circular hole (301) and a second power supply through hole (304) corresponding to the second circular hole (302). The RF connector-coupled patch combined feeding structure (4) includes a direct-connection Y-shaped coupling patch (402) and a connecting Y-shaped coupling patch (407) orthogonally printed on the upper surface of the horizontal dual-polarized radiating substrate (2) between intersecting quadrants. The direct-connection Y-shaped coupling patch (402) has a third circular hole (408) at its tail end, and the connecting Y-shaped coupling patch (407) has a fourth circular hole (409) at its tail end. One end of the inner core (401) of the first horizontally polarized RF connector is connected to the upper surface of the horizontal dual-polarized radiating substrate (2), and the other end passes through the third circular hole (408). The first feed through hole (303), the first round hole (301), the dielectric support plate (5) and the ground plane (7) are connected to the outer conductor (411) of the first horizontal polarized RF connector to form feed port one. One end of the inner core (410) of the second horizontal polarized RF connector is connected to the upper surface of the horizontal dual polarized radiation substrate (2), and the other end passes through the fourth round hole (409), the second feed through hole (304), the second round hole (302), the dielectric support plate (5) and the ground plane (7) respectively, and is connected to the outer conductor (412) of the second horizontal polarized RF connector to form feed port two. The RF connector-coupled patch combined power supply structure (4) also includes multiple metal short-circuit posts (403) equivalent to coaxial line outer conductors and multiple metal short-circuit posts (404) serving as short-circuit baluns, which are connected between the horizontal dual-polarized radiating substrate (2) and the ground plane (7) around the center of the dielectric support plate (5). The multiple metal short-circuit posts (403) equivalent to coaxial line outer conductors, the multiple short-circuit balun metal short-circuit posts (404), the inner core (401) of the first horizontally polarized RF connector, and the inner core (410) of the second horizontally polarized RF connector are distributed at equal angles and distances within the dielectric support plate (5). The number of the multiple metal short-circuit posts (403) equivalent to coaxial line outer conductors and the multiple short-circuit balun metal short-circuit posts (404) are all 4. The connecting Y-shaped coupling patch (407) is broken at the intersection with the direct Y-shaped coupling patch (402), and the two broken ends are connected by metal through holes (405) provided on the horizontal dual-polarized radiation substrate (2) and rectangular strips (406) printed on the lower surface of the horizontal dual-polarized radiation substrate (2). The vertically polarized antenna structure (6) includes a 1-to-4 equal power microstrip line (602) printed on the upper surface of the ground plane (7). The 1-to-4 equal power microstrip line (602) has a 50Ω central circular node (606) in the middle. At the ends of the 1-to-4 equal power microstrip line (602), there are end circular nodes (603). Vertical metal pillars (601) are respectively set on the end circular nodes (603). The top of the vertical metal pillars (601) is inserted into the dielectric support plate (5). The 50Ω central circular node (606) is connected to the end circular node (603) by a quarter impedance transformation line (607). The 50Ω central circular node (606) is connected to one end of the inner core of the vertically polarized RF connector (604). The other end of the inner core of the vertically polarized RF connector (604) passes through the ground plane (7) and is connected to the outer conductor (605) of the vertically polarized RF connector to form the third feed port.

2. The Ku-band miniature broadband high-isolation satellite communication tripolar unit according to claim 1, characterized in that: The ground plane (7) has a ground plane (706) printed on its lower surface. The top surfaces of the outer conductor (411) of the first horizontally polarized RF connector, the outer conductor (412) of the second horizontally polarized RF connector, and the outer conductor (605) of the vertically polarized RF connector are all in contact with the ground plane (706). The ground plane (7) has the inner core through hole (701) of the first horizontally polarized RF connector and the inner core through hole (702) of the second horizontally polarized RF connector that are adapted to the inner core (401) of the first horizontally polarized RF connector and the inner core (410) of the second horizontally polarized RF connector, respectively. There is also a coaxial outer conductor metal pillar through hole (703) adapted to the metal short-circuit post (403) equivalent to the coaxial outer conductor, a short-circuit balun metal pillar through hole (704) adapted to the short-circuit balun metal short-circuit post (404), and a vertically polarized RF connector inner core through hole (705) adapted to the inner core of the vertically polarized RF connector (604).

3. A small, broadband, high-isolation satellite communication tri-polarized array antenna based on the tri-polarized unit of any one of claims 1-2, characterized in that: The array includes n×n Ku-band small broadband high isolation satellite communication tripolar units, with the spacing between the centers of adjacent units being greater than the unit length. The Ku-band small broadband high isolation satellite communication tripolar unit includes a horizontal dual-polarization radiating substrate (2), a dielectric support plate (5), and a ground plane (7) arranged from top to bottom. A radio frequency connector-coupled patch combined feed structure (4) and a vertical polarization antenna structure (6) are respectively arranged between the horizontal dual-polarization radiating substrate (2) and the ground plane (7) and are vertically penetrating in the dielectric support plate (5). The entire array antenna shares a horizontal dual-polarization radiating substrate (2), a dielectric support plate (5), and a ground plane (7).

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