Circularly polarized antenna, antenna device and vehicle

Abstract

The utility model relates to the technical field of antennas, provides a circularly polarized antenna, an antenna device and a vehicle, and can solve the problem that the size of the circularly polarized antenna is too large in the prior art. The circularly polarized antenna comprises a floor, a dielectric plate, a plurality of first radiation arms, a plurality of parasitic radiation arms and a feed unit, the dielectric plate and the floor are arranged separately; the plurality of first radiation arms are arranged on the dielectric plate and form at least one crossed dipole; the multiple parasitic radiation arms are distributed at the edge of the dielectric plate in the circumferential direction of the dielectric plate, each parasitic radiation arm is coupled with the first radiation arm close to the parasitic radiation arm, each parasitic radiation arm is provided with a grounding end and an open end, the grounding end is connected to the floor, the open end is located at the edge of the dielectric plate, and the open end is connected to the ground. The cross sectional area of the parasitic radiation arm at the grounding end is smaller than that at the open end; the feed unit is used for feeding each first radiation arm. The device can be used on a vehicle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of antennas, and in particular to a circularly polarized antenna, an antenna device and a vehicle. BACKGROUND

[0002] Under the background of the continuous development of modern wireless communication technology, circularly polarized antennas have been widely used in many fields such as satellite communication, satellite navigation system, radio frequency identification and wireless local area network due to their unique performance advantages such as reducing multipath interference, resisting the Faraday rotation effect caused by the ionosphere and reducing mismatch loss.

[0003] Nowadays, the requirements for communication in the field of vehicle-mounted communication are increasing, and vehicles need to have satellite communication functions to support multi-network satellite communication. In the vehicle-mounted environment, in order to meet the demand of multi-network satellite communication, a circularly polarized antenna with wide bandwidth beam is needed to realize effective reception and transmission of signals of different frequency bands and ensure stable communication connection with the satellite during vehicle movement.

[0004] However, although the circularly polarized antenna in the related art has the advantage of wide bandwidth beam, it is difficult to adapt to the development trend of miniaturization of vehicle-mounted antennas due to its large size. In the limited space of the vehicle, the large-sized antenna is not only inconvenient to install, but also may affect the appearance and performance of the vehicle. Therefore, it is urgent to develop a miniaturized circularly polarized antenna to meet the demand of multi-network satellite communication in vehicles. CONTENT OF THE INVENTION

[0005] Embodiments of the present application provide a circularly polarized antenna, an antenna device and a vehicle, which are used to solve the problem of large size of the circularly polarized antenna in the related art.

[0006] To achieve the above-mentioned purpose, embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, the embodiments of the present application provide a circularly polarized antenna, which comprises a ground plate, a dielectric plate, a plurality of first radiation arms, a plurality of parasitic radiation arms and a feeding unit; the dielectric plate is arranged apart from the ground plate along the thickness direction of the dielectric plate; the plurality of first radiation arms are arranged on the dielectric plate and constitute at least one cross-dipole, the first end of each first radiation arm is arranged close to the center region of the dielectric plate, and the second end of each first radiation arm is arranged close to the edge of the dielectric plate; the plurality of parasitic radiation arms are distributed at the edge of the dielectric plate along the circumferential direction of the dielectric plate, each parasitic radiation arm is coupled with the first radiation arm close to it, each parasitic radiation arm has a grounded end and an open end, the grounded end is connected to the ground plate, the open end is located at the edge of the dielectric plate, the cross-sectional area of the parasitic radiation arm at the grounded end is smaller than that at the open end; and the feeding unit is used to feed each first radiation arm.

[0008] The cross-sectional area of the parasitic radiating arm at the ground end is set to be smaller than the cross-sectional area at the open end, which is equivalent to making the cross-sectional area of the parasitic radiating arm at the ground end smaller. According to the current distribution law of the parasitic radiating arm when the circularly polarized antenna is working, that is, the ground end is the maximum current point and the open end is the minimum current point, reducing the cross-sectional area of the parasitic radiating arm at the maximum current point can increase the inductance of the parasitic radiating arm. Since the resonant frequency of the antenna is inversely proportional to the inductance of the radiator, the increase of the inductance of the parasitic radiating arm can reduce the resonant frequency of the circularly polarized antenna, which is equivalent to increasing the electrical length of the radiator (here, the radiator refers to the first radiating arm and the parasitic radiating arm) in the circularly polarized antenna. Therefore, the physical length of the radiator does not need to be designed to be too large, thereby facilitating the reduction of the volume of the circularly polarized antenna to meet the installation requirements of the vehicle-mounted antenna.

[0009] In some embodiments of the first aspect, the parasitic radiating arm includes a first arm segment and a second arm segment, the second arm segment is connected between the first arm segment and the ground plate, the cross-sectional area of the second arm segment is smaller than that of the first arm segment, the open end is located at the first arm segment, and the ground end is located at the second arm segment. In this way, while ensuring the coupling efficiency between the parasitic radiating arm and the corresponding first radiating arm, the volume of the circularly polarized antenna can be reduced.

[0010] In some embodiments of the first aspect, the first arm segment and the second arm segment are both rectangular sheet structures, the length of the short side of the second arm segment is smaller than the length of the long side of the first arm segment, and the short side of the second arm segment is connected to the middle of the long side of the first arm segment. In this way, the axial ratio of the circularly polarized antenna can be optimized.

[0011] In some embodiments of the first aspect, the dielectric plate is a polygonal plate and has a plurality of corners, each parasitic radiating arm is located at a corresponding corner and forms a radiating arm group with a first radiating arm adjacent thereto, and in the radiating arm group, the parasitic radiating arm and the first radiating arm are dimensionally overlapped in the length direction of the first radiating arm and in the width direction of the first radiating arm. In this way, the volume of the circularly polarized antenna can be reduced.

[0012] In some embodiments of the first aspect, the dielectric plate is a polygonal plate and has a plurality of edges, each parasitic radiating arm is located at a corresponding edge and forms a radiating arm group with a first radiating arm adjacent thereto, and in the radiating arm group, the size of the parasitic radiating arm is smaller than that of the first radiating arm in the length direction of the first radiating arm, and the parasitic radiating arm is completely dimensionally overlapped with the first radiating arm. In this way, the volume of the circularly polarized antenna can be reduced.

[0013] In some embodiments of the first aspect, each first radiating arm is provided with a notch at the first end. In this way, the axial ratio of the circularly polarized antenna can be optimized.

[0014] In some embodiments of the first aspect, the dielectric plate comprises a first plate surface and a second plate surface arranged oppositely, the number of the first radiating arms is four, the four first radiating arms are arranged around the central region of the dielectric plate and form two cross dipoles, one cross dipole is arranged on the first plate surface and the other cross dipole is arranged on the second plate surface, and the first ends of the two first radiating arms in each cross dipole are connected by a phase delay line; the feeding unit is a coaxial cable, and comprises an outer conductor, an inner conductor, and an insulator filled between the outer conductor and the inner conductor, the coaxial cable extends to the central region of the dielectric plate, the outer conductor is electrically connected with one first radiating arm located on the second plate surface, the inner conductor passes through the dielectric plate and is electrically connected with one first radiating arm located on the first plate surface, and the two first radiating arms electrically connected with the inner conductor and the outer conductor respectively have the same extension direction. In this way, the outer conductor can effectively shield external electromagnetic interference, and at the same time, prevent internal signals from radiating outward, thereby helping to improve the electromagnetic compatibility of the circularly polarized antenna; at the same time, the structure of the feeding unit of the circularly polarized antenna can be made more compact, and the feeding unit can avoid occupying other space to cause the volume of the circularly polarized antenna to increase.

[0015] In some embodiments of the first aspect, on the first plate surface, the first end of one first radiating arm is provided with a first connecting flange, the first connecting flange extends into the region surrounded by the phase delay line and abuts against the inner conductor; on the second plate surface, the first end of one first radiating arm is provided with a second connecting flange, the second connecting flange extends into the region surrounded by the phase delay line and abuts against the outer conductor. In this way, the feeding unit can be electrically connected with the corresponding first radiating arm.

[0016] In the second aspect, the embodiments of the present application provide an antenna device, comprising an antenna array, the antenna array comprising a plurality of circularly polarized antennas in the first aspect.

[0017] The antenna device in the embodiments of the present application has the same beneficial effects as the circularly polarized antenna in the first aspect, which will not be repeated here.

[0018] In some embodiments of the second aspect, the number of circularly polarized antennas is three, and the three circularly polarized antennas are arranged in a triangle or L shape; the antenna device further comprises a phase adjustment unit and a switch switching unit; the phase adjustment unit has a first input port, a second input port, a first output port, and a second output port, the first input port and the second input port are respectively electrically connected to the communication transceiver; the first output port and the second output port are respectively used for outputting signals with a phase difference of 90°; the switch switching unit is electrically connected to the first input port, the second input port, and the three circularly polarized antennas, and the switch switching unit is used for electrically connecting the first input port and the second input port to any two circularly polarized antennas one by one. In this way, through the phase adjustment of the phase adjustment unit and the state switching of the switch switching unit, the antenna device can generate multiple beams, thereby realizing the coverage of the zenith wide beam, and further meeting the communication needs of the vehicle in different orientations.

[0019] In some embodiments of the second aspect, the phase adjustment unit is a 3dB bridge. In this way, the signal interference between different ports of the phase adjustment unit can be reduced.

[0020] In some embodiments of the second aspect, the switch switching unit is a double-pole four-throw switch, and the double-pole four-throw switch has two input contacts and four output contacts, the two input contacts are respectively connected to the first input port and the second input port one by one, and the three output contacts are respectively electrically connected to the three circularly polarized antennas. In this way, the isolation effect between different signal channels in the switch switching unit can be improved.

[0021] In some embodiments of the second aspect, the first input port is electrically connected to a satellite communication transceiver, and the second input port is electrically connected to a cellular communication transceiver. In this way, the antenna device can not only perform satellite communication to meet the satellite communication needs of the vehicle in different orientations, but also perform cellular communication to meet the cellular communication needs of the vehicle in different orientations, and has good communication effect for scenarios such as ground library and remote control.

[0022] In a third aspect, the embodiments of the present application provide a vehicle, comprising a vehicle body and the antenna device in the second aspect, and the antenna device is arranged on the vehicle body.

[0023] The vehicle in the embodiments of the present application has the same beneficial effects as the circularly polarized antennas in the first aspect, and will not be described here.

[0024] In some embodiments of the third aspect, the antenna device is arranged on the top of the vehicle body. In this way, the communication effect of the antenna device and the satellite can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1A structure diagram of a circularly polarized antenna in the first embodiment of the present application;

[0026] Figure 2 A structure diagram of a circularly polarized antenna in the first embodiment of the present application; Figure 1 A top view of the circularly polarized antenna shown in FIG. 1;

[0027] Figure 3 A bottom view of the circularly polarized antenna shown in FIG. 1 after removing the floor; Figure 1 A bottom view of the circularly polarized antenna shown in FIG. 1 after removing the dielectric plate;

[0028] Figure 4 A structure diagram of a circularly polarized antenna in the first embodiment of the present application; Figure 1 A structure diagram of a circularly polarized antenna in the first embodiment of the present application;

[0029] Figure 5a A structure diagram of a circularly polarized antenna in the first embodiment of the present application; Figure 2 An A-A sectional view of the circularly polarized antenna shown in FIG. 1;

[0030] Figure 5b An enlarged view of a part of the circularly polarized antenna shown in FIG. 1; Figure 5a

[0031] Figure 6a A current distribution diagram of the circularly polarized antenna shown in FIG. 1 when in a first resonance; Figure 1

[0032] Figure 6b A current distribution diagram of the circularly polarized antenna shown in FIG. 1 when in a second resonance; Figure 1

[0033] Figure 6c A current distribution diagram of the circularly polarized antenna shown in FIG. 1 when in a third resonance; Figure 1

[0034] Figure 6d A current distribution diagram of the circularly polarized antenna shown in FIG. 1 when in a fourth resonance; Figure 1

[0035] Figure 7a A S11 and antenna efficiency curve diagram of the circularly polarized antenna shown in FIG. 1; Figure 1

[0036] Figure 7b A zenith axis ratio curve diagram of the circularly polarized antenna shown in FIG. 1; Figure 1

[0037] Figure 7c A left-handed gain minimum value curve diagram of the circularly polarized antenna shown in FIG. 1 when in a beam elevation angle of 10° / 20°; Figure 1

[0038] Figure 8a A 3D directional diagram of the circularly polarized antenna shown in FIG. 1 at 1.52 GHz; Figure 1 ​​​​​​​​​

[0039] Figure 8b for Figure 8a The 3D radiation pattern shown is the radiation pattern in the XOZ section.

[0040] Figure 8c for Figure 8a The 3D radiation pattern shown is the radiation pattern in the YOZ cross-section;

[0041] Figure 8d for Figure 1 The 3D radiation pattern of the circularly polarized antenna at 2.2 GHz is shown.

[0042] Figure 8e for Figure 8d The 3D radiation pattern shown is the radiation pattern in the XOZ section.

[0043] Figure 8f for Figure 8d The 3D radiation pattern shown is the radiation pattern in the YOZ section.

[0044] Figure 9 This is a schematic diagram of the structure of the circularly polarized antenna in the second embodiment of this application;

[0045] Figure 10a for Figure 9 A top view of the circularly polarized antenna shown;

[0046] Figure 10b for Figure 9 The diagram shows the structure of the circularly polarized antenna after the dielectric substrate has been removed.

[0047] Figure 9 for Figure 10a The diagram shows the S11 of the circularly polarized antenna and its efficiency curve.

[0048] Figure 9 for Figure 10a The graph shows the zenith axial ratio of the circularly polarized antenna.

[0049] Figure 10a for Figure 10b The graph showing the maximum left-hand gain of the circularly polarized antenna is shown.

[0050] Figure 10a for Figure 9 The graph shows the minimum left-hand circular gain curve of the circularly polarized antenna at beam elevation angles of 10° / 20°.

[0051] Figure 10b for Figure 9 The 3D radiation pattern of the circularly polarized antenna at 1.52 GHz is shown.

[0052] Figure 10b for Figure 11a3D pattern shown in XOZ plane;

[0053] Figure 9 As shown in the 3D pattern shown in XOZ plane; Figure 11b 3D pattern shown in YOZ plane;

[0054] Figure 9 As shown in the 3D pattern shown in YOZ plane; Figure 11c 3D pattern of the circularly polarized antenna shown at 2.2 GHz;

[0055] Figure 9 As shown in the 3D pattern shown in XOZ plane; Figure 11d 3D pattern shown in YOZ plane;

[0056] Figure 9 As shown in the 3D pattern shown in YOZ plane; Figure 11a-11d

[0057] As shown in the structure diagram of the vehicle in the present application; Figure 12a

[0058] As shown in the top view of the vehicle in the present application; Figure 9 Figure 12b As shown in the internal structure diagram of the antenna device of the vehicle in the present application;

[0059] Figure 12a Figure 12c As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0060] Figure 12a As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0061] Figure 12a As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application; Figure 12b

[0062] As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application; Figure 12c Figure 12d As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0063] Figure 9 As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0064] Figure 12e As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0065] Figure 12d As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;

[0066] Figure 12f As shown in the principle diagram of the antenna beam pointing in the antenna device shown in the present application;​​​

[0067] Figure 12d Communication effect diagram of the antenna device in the embodiment of the present application at different beam elevation angles;

[0068] Figure 12d Antenna gain comparison diagram of the antenna device in the embodiment of the present application and the gain of the existing cellular antenna;

[0069] Figure 12e Internal structure schematic diagram of the antenna device in another embodiment of the present application. DETAILED DESCRIPTION

[0070] Under the background of the continuous development of modern wireless communication technology, circularly polarized antennas play a key role in many fields due to their unique performance advantages.

[0071] Circularly polarized antennas have significant characteristics such as reducing multipath interference, resisting the Faraday rotation effect caused by the ionosphere, and reducing mismatch loss. In a multipath interference scenario, its circular polarization characteristic causes a part of the multipath signals to cancel each other out on a time average, effectively reducing the interference impact; in scenarios involving ionospheric propagation such as satellite communication, it can adapt to the polarization plane rotation caused by the ionosphere to ensure stable signal transmission; at the same time, due to its certain receiving ability to different polarized form signals, it can reduce the loss caused by polarization mismatch. These advantages make circularly polarized antennas widely used in modern wireless communication systems such as satellite communication, satellite navigation systems, radio frequency identification (RFID), wireless local area networks (WLAN), etc.

[0072] Nowadays, the requirements for communication in the field of vehicle-mounted communication are increasing, and vehicles need to have satellite communication functions to support multi-network satellite communication. For example, Tian Tong satellite communication system (transmission frequency band: 1980-2010 MHz, reception frequency band: 2170-2200 MHz) and Xingwang satellite communication system (transmission frequency band: 1668-1675 MHz, reception frequency band: 1518-1525 MHz). In the vehicle-mounted environment, to meet the demand of multi-network satellite communication, a circularly polarized antenna with wide bandwidth beam is needed to realize effective reception and transmission of signals of different frequency bands and ensure stable communication connection with the satellite during vehicle movement.

[0073] However, as shown in Table 1, although the circularly polarized antennas in the related art have the advantage of wide bandwidth beam, they are difficult to adapt to the development trend of miniaturization of vehicle-mounted antennas due to their large antenna size. In the limited space of the vehicle, the large antenna not only is inconvenient to install, but also may affect the appearance and performance of the vehicle. Therefore, it is urgent to develop a miniaturized circularly polarized antenna to meet the demand of multi-network satellite communication in vehicles.

[0074] Table 1 Parameters of some circularly polarized antennas in the related art and requirements of vehicle-mounted antennas

[0075]

[0076] wherein, λ is the wavelength of the left edge frequency point of the 3dB axial ratio passband. a x b x c in the antenna size represents "length x width x height".

[0077] To this end, the application provides a circularly polarized antenna, an antenna device and a vehicle, by arranging a parasitic radiation arm for grounding around the crossed dipoles in the circularly polarized antenna, and the parasitic radiation arm has a smaller cross-sectional area at the grounding end, which is equivalent to increasing the electrical length of the parasitic radiation arm, which is beneficial to reducing the physical size of the overall radiator of the antenna when the overall electrical length of the antenna is constant, thereby miniaturizing the circularly polarized antenna to meet the installation requirements of the vehicle-mounted antenna.

[0078] Figure 12f Fig. 1 is a structural schematic diagram of a circularly polarized antenna in a first embodiment of the application, Figure 13 Fig. 2 is a top view of the circularly polarized antenna shown in Fig. 1, Figure 14 Fig. 3 is a bottom view of the circularly polarized antenna shown in Fig. 1 after removing the floor 1, Figure 13 Fig. 4 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As Figure 15 Fig. 5 is a bottom view of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. Figure 13 Fig. 6 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As Figure 13-15 Fig. 7 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As Figure 15 Fig. 8 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As

[0079] As Figure 13 Fig. 9 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As

[0080] As Figure 14 Fig. 10 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As

[0081] As Figure 13 Fig. 11 is a structural schematic diagram of the circularly polarized antenna shown in Fig. 1 after removing the dielectric plate 2. As

[0082] AsFigure 14 、 Figure 13 and Figure 14 As shown in

[0083] wherein, in some embodiments, as shown in Figure 15 、 Figure 14 and Figure 15 the dielectric plate 2 comprises a first plate face 2a and a second plate face 2b arranged oppositely, the number of the first radiating arms 31 is four, which are the first radiating arm 31a, the first radiating arm 31b, the first radiating arm 31c and the first radiating arm 31d respectively; the first radiating arm 31a, the first radiating arm 31b, the first radiating arm 31c and the first radiating arm 31d are arranged around the central region 21 of the dielectric plate 2 and constitute two cross-dipoles 30, as shown in Figure 15 one cross-dipole 30 (i.e. the cross-dipole 30 constituted by the first radiating arm 31a and the first radiating arm 31b) is arranged on the first plate face 2a, as shown in Figure 14 the other cross-dipole 30 (i.e. the cross-dipole 30 constituted by the first radiating arm 31c and the first radiating arm 31d) is arranged on the second plate face 2b, and the first ends of the two first radiating arms 31 in each cross-dipole 30 are connected through a phase delay line 34.

[0084] Of course, the number of the first radiating arms 31 can also be two, the two first radiating arms 31 constitute one cross-dipole 30 and are arranged on the first plate face 2a.

[0085] As shown in Figure 15 、 Figure 15 and Figure 15 the number of the parasitic radiating arms 32 is multiple, the multiple parasitic radiating arms 32 are distributed at the edge 22 of the dielectric plate 2 along the circumference of the dielectric plate 2, each parasitic radiating arm 32 is coupled with the proximate first radiating arm 31 respectively, each parasitic radiating arm 32 has a grounded end 3201 and an open end 3202, the grounded end 3201 is connected to the ground plate 1, the open end 3202 is located at the edge 22 of the dielectric plate 2, the cross-sectional area of the parasitic radiating arm 32 at the grounded end 3201 is smaller than that at the open end 3202.

[0086] The cross-sectional area of the parasitic radiation arm 32 is specifically the area of the cross-section presented by the parasitic radiation arm 32 after being cut by a plane perpendicular to the thickness direction of the floor 1. The ground end 3201 and the open end 3202 are relative to whether it is grounded or not. The ground end 3201 is grounded, and the open end 3202 is not grounded. The parasitic radiation arm 32 can be arranged on the support side plate 5.

[0087] In some embodiments, as shown in Figure 15 and Figure 16 , the number of parasitic radiation arms 32 can be equal to the number of first radiation arms 31. The plurality of parasitic radiation arms 32 are coupled to the plurality of first radiation arms 31 one by one, such as Figure 17 shown, the plurality of parasitic radiation arms 32 are parasitic radiation arm 32a, parasitic radiation arm 32b, parasitic radiation arm 32c, and parasitic radiation arm 32d. The first radiation arm 31a is coupled to the parasitic radiation arm 32a, the first radiation arm 31b is coupled to the parasitic radiation arm 32b, the first radiation arm 31c is coupled to the parasitic radiation arm 32c, and the first radiation arm 31d is coupled to the parasitic radiation arm 32d.

[0088] Of course, the number of parasitic radiation arms 32 can also be different from the number of first radiation arms 31, such as the number of parasitic radiation arms 32 can be twice the number of first radiation arms 31.

[0089] As shown in Figure 16 and Figure 18 , the feeding unit 4 is used to feed each first radiation arm 31.

[0090] The cross-sectional area of the parasitic radiation arm 32 at the ground end 3201 is set to be smaller than the cross-sectional area at the open end 3202, which is equivalent to making the cross-sectional area of the parasitic radiation arm 32 at the ground end 3201 smaller. According to the current distribution rule of the parasitic radiation arm 32 when the circularly polarized antenna is working, that is, the ground end 3201 is the maximum current point and the open end 3202 is the minimum current point, reducing the cross-sectional area of the parasitic radiation arm 32 at the maximum current point can increase the inductance of the parasitic radiation arm 32. Since the resonant frequency of the antenna is inversely proportional to the inductance of the radiator, the increase of the inductance of the parasitic radiation arm 32 can reduce the resonant frequency of the circularly polarized antenna, which is equivalent to increasing the electrical length of the radiator (here, the radiator refers to the first radiation arm 31 and the parasitic radiation arm 32) in the circularly polarized antenna. Therefore, the physical length of the radiator does not need to be designed to be too large, which is beneficial to reduce the volume of the circularly polarized antenna to meet the installation requirements of the vehicle-mounted antenna. For example, compared with the circularly polarized antenna in the related art [3], the antenna size of the circularly polarized antenna in the embodiment of the present application can be reduced from 0.28λx0.28λx0.11λ to 0.2λx0.2λx0.09λ, the antenna layout area is reduced by 49%, which greatly reduces the occupied area of the circularly polarized antenna and helps to miniaturize the circularly polarized antenna product.

[0091] In some embodiments, as shown in Figure 16 and Figure 15 The medium plate 2 is a polygonal plate having a plurality of edges 22 and a plurality of corners 23. The plurality of edges 22 are edge 22a, edge 22b, edge 22c, and edge 22d respectively. The corners 23 are formed at the junctions of the above-mentioned adjacent two edges 22.

[0092] Each parasitic radiation arm 32 is located at a corresponding corner 23 and forms a radiation arm group 33 with the first radiation arm 31 adjacent thereto. For example Figure 16 、 Figure 17 and Figure 18 The parasitic radiation arm 32a and the first radiation arm 31a constitute a radiation arm group 33; the parasitic radiation arm 32b and the first radiation arm 31b constitute a radiation arm group 33; the parasitic radiation arm 32c and the first radiation arm 31c constitute a radiation arm group 33; and the parasitic radiation arm 32d and the first radiation arm 31d constitute a radiation arm group 33.

[0093] In the radiation arm group 33, the parasitic radiation arm 32 and the first radiation arm 31 are dimensionally overlapped in the length direction of the first radiation arm 31 and in the width direction of the first radiation arm 31. For example Figure 15As shown, in the radiation arm group 33 composed of the parasitic radiation arm 32b and the first radiation arm 31b, along the length direction X of the first radiation arm 31b, at least a part of the orthographic projection of the first radiation arm 31b on the corresponding edge 22b overlaps with the orthographic projection of the parasitic radiation arm 32b on the corresponding edge 22b; along the width direction Y of the first radiation arm 31b, at least a part of the orthographic projection of the first radiation arm 31b on the corresponding edge 22c overlaps with the orthographic projection of the parasitic radiation arm 32b on the corresponding edge 22c.

[0094] The length direction of the first radiation arm 31 refers to the direction from the first end of the first radiation arm 31 to the second end, or the direction from the second end of the first radiation arm 31 to the first end, and the width direction of the first radiation arm 31 is perpendicular to the length direction of the first radiation arm 31 and the thickness direction H of the dielectric plate 2.

[0095] In this way, the parasitic radiation arm 32 is coupled with the first radiation arm 31 in both the length direction and the width direction of the first radiation arm 31, which is conducive to increasing the coupling area between the parasitic radiation arm 32 and the first radiation arm 31, increasing the coupling capacitance between the parasitic radiation arm 32 and the first radiation arm 31, and prolonging the electrical length of the first radiation arm 31. Thus, when the electrical length of the first radiation arm 31 is required to be a certain value, the physical size of the first radiation arm 31 does not need to be set too large, thereby facilitating the reduction of the volume of the circularly polarized antenna.

[0096] In some embodiments, as shown in Figure 16 and Figure 18 The parasitic radiation arm 32 includes a first arm segment 321 and a second arm segment 322, the second arm segment 322 is connected between the first arm segment 321 and the ground plate 1, the cross-sectional area of the second arm segment 322 is smaller than that of the first arm segment 321, the open end 3202 is located at the first arm segment 321, and the grounded end 3201 is located at the second arm segment 322. That is, the cross-sectional area of the first arm segment 321 is set to be larger, and the cross-sectional area of the second arm segment 322 is set to be smaller. By setting the cross-sectional area of the first arm segment 321 to be larger, the coupling efficiency between the parasitic radiation arm 32 and the corresponding first radiation arm 31 is increased; by setting the cross-sectional area of the second arm segment 322 to be smaller, the inductance of the parasitic radiation arm 32 is increased, thereby ensuring the coupling efficiency between the parasitic radiation arm 32 and the corresponding first radiation arm 31 while reducing the volume of the circularly polarized antenna.

[0097] In order to optimize the axial ratio of the circularly polarized antenna, in some embodiments, as shown in Figure 16 and Figure 16As shown, the first arm segment 321 and the second arm segment 322 are both rectangular sheet structures, the length of the short side of the second arm segment 322 is less than the length of the long side of the first arm segment 321, and the short side of the second arm segment 322 is connected to the middle of the long side of the first arm segment 321, such as the midpoint of the long side. That is, the grounding position of the first arm segment 321 is located in the middle of the long side of the first arm segment 321. In this way, the electric field and magnetic field distribution of the circularly polarized antenna can be better adjusted, the amplitudes of the two orthogonal polarization components generated by the circularly polarized antenna are closer to equal, and the phase difference is closer to 90°, so that the energy radiation of different polarization directions can be balanced, and the axial ratio of the circularly polarized antenna can be optimized.

[0098] In order to optimize the axial ratio of the circularly polarized antenna, in some embodiments, as shown in Figure 16 and Figure 19 , a notch 311 is arranged at the first end of each first radiating arm 31. By arranging the notch 311, the current path on the first radiating arm 31 changes, the current distribution on the first radiating arm 31 can be changed, and the distribution of the electric field generated around the circularly polarized antenna in two orthogonal directions is adjusted to optimize the axial ratio of the circularly polarized antenna.

[0099] In some embodiments, the feeding unit 4 can be a coaxial cable, as shown in Figure 20 , Figure 19 and Figure 20 , as shown in Figure 21 , the A-A sectional view of the circularly polarized antenna shown in Figure 22 , the partial enlarged view of Figure 23 , and Figure 21 . The feeding unit 4 includes an outer conductor 41, an inner conductor 42, and an insulator 43 filled between the outer conductor 41 and the inner conductor 42. The coaxial cable extends to the center region 21 of the dielectric plate 2, and the outer conductor 41 is electrically connected to one first radiating arm 31 located on the second plate surface 2b. The inner conductor 42 passes through the dielectric plate 2 and is electrically connected to one first radiating arm 31 located on the first plate surface 2a. The two first radiating arms 31 electrically connected to the inner conductor 42 and the outer conductor 41 respectively have the same extension direction, such as Figure 22 and Figure 23 , as shown, the first radiating arm 31c is electrically connected to the outer conductor 41, the first radiating arm 31a is electrically connected to the inner conductor 42, and the first radiating arm 31c and the first radiating arm 31a both extend along the Y direction.

[0100] The feeding unit 4 is arranged as a coaxial cable, and the coaxial cable comprises an outer conductor 41, an inner conductor 42 and an insulator 43. In this way, the outer conductor can effectively shield external electromagnetic interference, and meanwhile, prevent internal signals from being radiated outward, thereby helping to improve the electromagnetic compatibility of the circularly polarized antenna. In addition, the coaxial cable extends to the central region 21 of the dielectric plate 2 and is electrically connected with the first radiation arm 31 on the first plate surface 2a and the second plate surface 2b respectively. In this way, the structure of the feeding unit 4 of the circularly polarized antenna can be more compact, and the feeding unit 4 can avoid occupying other space to cause the volume of the circularly polarized antenna to increase.

[0101] In some embodiments, as shown in Figure 24 , the first radiation arm 31a is electrically connected with the inner conductor 42, and the phase of the first radiation arm 31a can be 0°. The first radiation arm 31b is electrically connected with the first radiation arm 31a through the phase delay line 34, and the phase of the first radiation arm 31b lags behind the phase of the first radiation arm 31a by 90°. The first radiation arm 31c is electrically connected with the outer conductor 41, and the phase of the first radiation arm 31c lags behind the phase of the first radiation arm 31a by 180°. The first radiation arm 31d is electrically connected with the first radiation arm 31c through the phase delay line 34, and the phase of the first radiation arm 31d lags behind the phase of the first radiation arm 31c by 90°.

[0102] In some embodiments, as shown in Figure 24 and Figure 24 , on the first plate surface 2a, the first end of one first radiation arm 31 (such as the first radiation arm 31a) is provided with a first connecting flange 312, and the first connecting flange 312 extends into the area surrounded by the phase delay line 34 and abuts against the inner conductor 42. Figure 24 and Figure 24 , on the second plate surface 2b, the first end of one first radiation arm 31 is provided with a second connecting flange 313, and the second connecting flange 313 extends into the area surrounded by the phase delay line 34 and abuts against the outer conductor 41.

[0103] By arranging the first connecting flange 312 and the second connecting flange 313, the first connecting flange 312 and the second connecting flange 313 play the role of intermediate connection, and the feeding unit 4 can be electrically connected with the corresponding first radiation arm 31 conveniently. Meanwhile, the first connecting flange 312 and the second connecting flange 313 extend into the area surrounded by the corresponding phase delay line 34, so that the first connecting flange 312 and the second connecting flange 313 can avoid interfering with the corresponding phase delay line 34.

[0104] In some embodiments, as shown in Figure 25 and Figure 25 , the phase delay line 34 can be an arc line, but is not limited thereto. The phase delay line 34 can also be a broken line.

[0105] The feed unit 4 is not limited to a coaxial cable, and can be a microstrip line.

[0106] Figure 25 The current distribution of the circularly polarized antenna shown in FIG. 1 at the first resonance, Figure 25 The current distribution of the circularly polarized antenna shown in FIG. 1 at the second resonance, ​ The current distribution of the circularly polarized antenna shown in FIG. 1 at the third resonance, ​ The current distribution of the circularly polarized antenna shown in FIG. 1 at the fourth resonance. ​ ​ The current distribution of the circularly polarized antenna shown in FIG. 1 at the fourth resonance. ​ ​ The current distribution of the circularly polarized antenna shown in FIG. 1 at the fourth resonance.

[0107] In some embodiments, the circularly polarized antenna has a first resonance, a second resonance, a third resonance, and a fourth resonance. The first resonance is a resonance at 1.48 GHz, the second resonance is a resonance at 1.54 GHz, the third resonance is a resonance at 2.2 GHz, and the fourth resonance is a resonance at 3 GHz.

[0108] As shown in FIG. 2, the first resonance of the circularly polarized antenna is generated by the cross-dipole 30 and the parasitic radiating arms 32. When the circularly polarized antenna is at the first resonance, the current flow directions of the cross-dipole 30 and the two adjacent parasitic radiating arms 32 are the same (i.e., counterclockwise as shown in FIG. 2), and the parasitic radiating arms 32 function to extend the electrical length of the coupled first radiating arms 31. ​ ​ As shown in FIG. 3, the second resonance of the circularly polarized antenna is also generated by the cross-dipole 30 and the parasitic radiating arms 32. When the circularly polarized antenna is at the second resonance, the current flow directions of the cross-dipole 30 and the two adjacent parasitic radiating arms 32 are the same, and the parasitic radiating arms 32 function to extend the electrical length of the adjacent first radiating arms 31.

[0109] As shown in FIG. 4, the third resonance of the circularly polarized antenna is also generated by the cross-dipole 30 and the parasitic radiating arms 32. When the circularly polarized antenna is at the third resonance, the current flow directions of two parasitic radiating arms 32 and the adjacent first radiating arms 31 are the same, and the current flow directions of the other two parasitic radiating arms 32 and the adjacent first radiating arms 31 are opposite, and the parasitic radiating arms 32 function to adjust the current amplitude of the two cross-dipoles 30. ​ As shown in FIG. 5, the fourth resonance of the circularly polarized antenna is generated by the cross-dipole 30 itself. When the circularly polarized antenna is at the fourth resonance, the current is mainly concentrated on the cross-dipole 30.

[0110] ​ As shown in FIG. 5, the fourth resonance of the circularly polarized antenna is generated by the cross-dipole 30 itself. When the circularly polarized antenna is at the fourth resonance, the current is mainly concentrated on the cross-dipole 30.

[0111] As shown in FIG. 5, the fourth resonance of the circularly polarized antenna is generated by the cross-dipole 30 itself. When the circularly polarized antenna is at the fourth resonance, the current is mainly concentrated on the cross-dipole 30. ​ ​​​​​

[0112] ​ S11 and antenna efficiency curves of the circularly polarized antenna shown in FIG. 8, ​ ​ S11 and antenna efficiency curves of the circularly polarized antenna shown in FIG. 8, ​ ​ S11 and antenna efficiency curves of the circularly polarized antenna shown in FIG. 8, ​ S11 and antenna efficiency curves of the circularly polarized antenna shown in FIG. 8,

[0113] ​ , ​ , ​ In the transmitting and receiving frequency band of the satellite communication system, the antenna efficiency of the circularly polarized antenna is greater than -1.0 dB, the zenith-to-boresight ratio of the circularly polarized antenna is less than 5.2 dB, and the left-handed gain at an elevation angle of 20° (i.e., Theta is 70°) is greater than or equal to -2.8 dBic.

[0114] In the transmitting and receiving frequency band of the satellite communication system, the antenna efficiency of the circularly polarized antenna is greater than -1.0 dB, the zenith-to-boresight ratio of the circularly polarized antenna is less than 5.2 dB, and the left-handed gain at an elevation angle of 20° (i.e., Theta is 70°) is greater than or equal to -2.8 dBic.

[0115] ​ 3D radiation pattern of the circularly polarized antenna shown in FIG. 10 at 1.52 GHz, ​ ​ ​ ​ ​ ​ , ​ and ​ As can be seen from the radiation patterns shown in FIGS. 10A, 10B and 10C, the radiation pattern of the circularly polarized antenna in the first embodiment of the present application at 1.52 GHz exhibits the characteristics of multiple lobes, upward radiation and wide beam, and can better meet the needs of satellite communication.

[0116] ​ 3D radiation pattern of the circularly polarized antenna shown in FIG. 12 at 2.2 GHz, ​ ​ ​ ​ ​ ​ , ​ and ​ As can be seen from the radiation patterns shown in FIGS. 12A, 12B and 12C, the radiation pattern of the circularly polarized antenna in the first embodiment of the present application at 2.2 GHz exhibits the characteristics of multiple lobes, upward radiation and wide beam, and can better meet the needs of satellite communication.​​​​​​​​​​​​​

[0117] ​ Fig. 2 is a structural schematic diagram of a circularly polarized antenna in a second embodiment of the present application, ​ Fig. 3 is a top view of a circularly polarized antenna, ​ Fig. 4 is a structural schematic diagram of a circularly polarized antenna after removing a dielectric plate 2, ​ Fig. 5 is a top view of a circularly polarized antenna, ​ Fig. 6 is a structural schematic diagram of a circularly polarized antenna after removing a dielectric plate 2. The main difference between the circularly polarized antenna in the second embodiment of the present application and the circularly polarized antenna in the first embodiment is that the position relationship between the parasitic radiation arm 32 and the first radiation arm 31 adjacent thereto is different, which is described as follows:

[0118] As shown in Figs. 3 and 5, the dielectric plate 2 is a polygonal plate and has a plurality of edges 22, and each parasitic radiation arm 32 is located at a corresponding edge 22 and forms a radiation arm group 33 with the first radiation arm 31 adjacent thereto. ​ and ​ As shown in Figs. 3 and 5, the dielectric plate 2 is a polygonal plate and has a plurality of edges 22, and each parasitic radiation arm 32 is located at a corresponding edge 22 and forms a radiation arm group 33 with the first radiation arm 31 adjacent thereto.

[0119] For example, as shown in Figs. 3 and 5, the dielectric plate 2 has four edges 22, which are edge 22a, edge 22b, edge 22c and edge 22d, and the number of parasitic radiation arms 32 is four, which are parasitic radiation arm 32a, parasitic radiation arm 32b, parasitic radiation arm 32c and parasitic radiation arm 32d. The parasitic radiation arm 32a is arranged at the edge 22a, the parasitic radiation arm 32b is arranged at the edge 22b, the parasitic radiation arm 32c is arranged at the edge 22c, and the parasitic radiation arm 32d is arranged at the edge 22d. The parasitic radiation arm 32a and the first radiation arm 31a constitute a radiation arm group 33. The parasitic radiation arm 32b and the first radiation arm 31b constitute a radiation arm group 33. The parasitic radiation arm 32c and the first radiation arm 31c constitute a radiation arm group 33. The parasitic radiation arm 32d and the first radiation arm 31d constitute a radiation arm group 33. ​ ​ As shown in Figs. 3 and 5, in the radiation arm group 33, in the length direction of the first radiation arm 31, the size of the parasitic radiation arm 32 is smaller than the size of the first radiation arm 31, and the parasitic radiation arm 32 completely overlaps the first radiation arm 31 in size.

[0120] As shown in Figs. 3 and 5, in the radiation arm group 33, in the length direction of the first radiation arm 31, the size of the parasitic radiation arm 32 is smaller than the size of the first radiation arm 31, and the parasitic radiation arm 32 completely overlaps the first radiation arm 31 in size. ​ ​ For example, as shown in Figs. 3 and 5, in the radiation arm group 33, in the length direction of the first radiation arm 31, the size of the parasitic radiation arm 32 is smaller than the size of the first radiation arm 31, and the parasitic radiation arm 32 completely overlaps the first radiation arm 31 in size.

[0121] For example, as shown in Figs. 3 and 5, in the radiation arm group 33, in the length direction of the first radiation arm 31, the size of the parasitic radiation arm 32 is smaller than the size of the first radiation arm 31, and the parasitic radiation arm 32 completely overlaps the first radiation arm 31 in size. ​ For example, as shown in Figs. 3 and 5, in the radiation arm group 33, in the length direction of the first radiation arm 31, the size of the parasitic radiation arm 32 is smaller than the size of the first radiation arm 31, and the parasitic radiation arm 32 completely overlaps the first radiation arm 31 in size.

[0122] ​​In this way, the coupling area of the parasitic radiation arm 32 and the corresponding first radiation arm 31 is increased, the coupling capacitance between the parasitic radiation arm 32 and the first radiation arm 31 is increased, and the electrical length of the first radiation arm 31 is extended. Thus, when the electrical length of the first radiation arm 31 is required, the physical size of the first radiation arm 31 does not need to be set too large, thereby facilitating reduction of the volume of the circularly polarized antenna.

[0123] In some embodiments, as shown in ​ and ​ , the parasitic radiation arm 32 includes a first arm segment 321 and a second arm segment 322, the second arm segment 322 is connected between the first arm segment 321 and the ground plane 1, the cross-sectional area of the second arm segment 322 is smaller than that of the first arm segment 321, the open end 3202 is located at the first arm segment 321, and the grounded end 3201 is located at the second arm segment 322. That is, the cross-sectional area of the first arm segment 321 is set to be larger, and the cross-sectional area of the second arm segment 322 is set to be smaller.

[0124] In some embodiments, as shown in ​ and ​ , the first arm segment 321 and the second arm segment 322 are both rectangular sheet structures, the length of the short side of the second arm segment 322 is smaller than that of the long side of the first arm segment 321, the short side of the second arm segment 322 is connected to the middle part (such as the midpoint) of the long side of the first arm segment 321, and the second arm segment 322 and the first arm segment 321 together form a T-shaped sheet structure.

[0125] ​ The S11 and antenna efficiency curves of the circularly polarized antenna shown in ​ , the zenith-to-boresight ratio curve of the circularly polarized antenna shown in ​ , the left-handed gain maximum value curve of the circularly polarized antenna shown in ​ , and the left-handed gain minimum value curve of the circularly polarized antenna at a beam elevation angle of 10° / 20° shown in ​ , and ​ . ​ , and ​ .

[0126] As shown in ​ , in the transceiving frequency band of the Star Network satellite communication system, the antenna efficiency of the circularly polarized antenna is greater than -0.9 dB, the zenith-to-boresight ratio of the circularly polarized antenna is less than 5 dB, and the left-handed gain at an elevation angle of 20° (i.e., Theta is 70°) is greater than or equal to -2.4 dBic.

[0127] In the transceiving frequency band of the Tian Tong satellite communication system, the antenna efficiency of the circularly polarized antenna is greater than -0.6 dB, the zenith-to-boresight ratio of the circularly polarized antenna is less than 3 dB, and the left-handed gain at an elevation angle of 20° (i.e., Theta is 70°) is greater than or equal to -1.2 dBic.

[0128] ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ , ​ and ​ As shown in the 3D pattern in XOZ section,

[0129] ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ As shown in the 3D pattern in XOZ section, ​ , ​ and ​ As shown in the 3D pattern in XOZ section,

[0130] The above is the introduction of the circularly polarized antenna in the embodiments of the present application, the application scenarios of the circularly polarized antenna in the embodiments of the present application are introduced below.

[0131] ​ As shown in the structure schematic diagram of the vehicle in the embodiments of the present application, ​ As shown in the top view of the vehicle in the embodiments of the present application, ​ As shown in the internal structure schematic diagram of the antenna device 1000 of the vehicle in the embodiments of the present application. As shown in the embodiments of the present application, ​ As shown in the internal structure schematic diagram of the antenna device 1000 of the vehicle in the embodiments of the present application. As shown in the embodiments of the present application, ​ As shown in the internal structure schematic diagram of the antenna device 1000 of the vehicle in the embodiments of the present application. As shown in the embodiments of the present application, ​ As shown in the internal structure schematic diagram of the antenna device 1000 of the vehicle in the embodiments of the present application. As shown in the embodiments of the present application, ​ As shown in the internal structure schematic diagram of the antenna device 1000 of the vehicle in the embodiments of the present application. As shown in the embodiments of the present application,

[0132] The vehicle can be a sport utility vehicle (SUV), a multi-purpose vehicle (MPV), a sedan, a recreational vehicle, a van, a bus, a truck, etc., and is not limited herein.

[0133] To improve the communication effect of the antenna device 1000 and the satellite, in some embodiments, as shown in ​ and ​ , the antenna device 1000 is arranged on the top of the vehicle body 2000. For example, as shown in ​ and ​ , the antenna device 1000 can be arranged on the outer surface of the top wall of the vehicle body 2000.

[0134] Of course, it is not limited to this, the antenna device 1000 can be embedded in the top wall of the vehicle body 2000, and can also be arranged at other parts of the vehicle body 2000, which can be determined according to actual conditions.

[0135] To better protect the antenna array 200, in some embodiments, as shown in ​ , ​ and ​ , the antenna device 1000 further includes a shell 600, and the antenna array 200 is arranged in the shell 600.

[0136] In some embodiments, as shown in ​ and ​ , the number of circularly polarized antennas 100 is three, and the three circularly polarized antennas 100 are circularly polarized antenna 100a, circularly polarized antenna 100b, and circularly polarized antenna 100c, wherein, as shown in ​ , the three circularly polarized antennas 100 are arranged in a triangular shape.

[0137] In some embodiments, as shown in ​ and ​ , the circularly polarized antenna 100b and the circularly polarized antenna 100c are arranged along the width direction W of the vehicle body 2000 to form an antenna row, and the circularly polarized antenna 100a is arranged along the length direction L of the vehicle body 2000.

[0138] Among them, in some embodiments, as shown in ​ , the circularly polarized antenna 100a is arranged close to the circularly polarized antenna 100b along the arrangement direction of the circularly polarized antenna 100b and the circularly polarized antenna 100c (such as the width direction W of the vehicle body 2000). For example, as shown in ​ , the circularly polarized antenna 100c is symmetrically arranged about the center plane F, and the center point O of the circularly polarized antenna 100a is located on the side of the center plane F close to the circularly polarized antenna 100b.

[0139] In addition to being arranged in a triangular pattern, the three circularly polarized antennas 100 can also be arranged in an L-shape.

[0140] In some embodiments, such as ​ As shown, a first circuit board 800 is provided inside the housing 600, and circularly polarized antennas 100a, 100b, and 100c are disposed on the carrier substrate of the first circuit board 800.

[0141] ​ This is a schematic block diagram of the antenna device 1000 in the embodiments of this application. ​ for ​ The diagram shows the principle of antenna beam pointing in antenna device 1000. ​ for ​ The antenna device 1000 shown can generate a beam pattern.

[0142] In some embodiments, such as ​ and ​ As shown, the antenna device also includes a phase adjustment unit 300 and a switch unit 400. The phase adjustment unit 300 has a first input port I1, a second input port I2, a first output port P1, and a second output port P2. The first input port I1 and the second input port I2 are respectively used to electrically connect to a communication transceiver. The first output port P1 and the second output port P2 are respectively used to output signals with a phase difference of 90°. The switch unit 400 is electrically connected to the first input port I1, the second input port I2, and the three circularly polarized antennas 100, respectively. The switch unit 400 is used to make the first input port I1 and the second input port I2 electrically connected to any two circularly polarized antennas 100 in a one-to-one correspondence.

[0143] By switching the state of the switch unit 400, the phase adjustment unit 300 can be electrically connected to any two circularly polarized antennas 100, enabling the two circularly polarized antennas 100 electrically connected to the phase adjustment unit 300 to operate. Since the output port P1 and the second output port P2 are respectively used to output signals with a phase difference of 90°, thus... ​ As shown, the beams generated by the two circularly polarized antennas 100 electrically connected to the phase adjustment unit 300 will point to the side where the phase-lagging circularly polarized antenna 100 is located. Thus, through phase adjustment by the phase adjustment unit 300 and state switching by the switch unit 400, the antenna device 1000 can generate various beams, such as... ​ The front beam, rear beam, left beam, right beam, upper left corner beam, and lower right corner beam shown in the diagram achieve zenith wide beam coverage, thereby meeting the communication needs of vehicles in different orientations.

[0144] In some embodiments, such as​ 、 ​ and ​ As shown in FIG. 4, when the switch switching unit 400 switches the circularly polarized antenna 100a and the circularly polarized antenna 100b to be electrically connected to the first input port I1 and the second input port I2 of the phase adjustment unit 300, the antenna device 1000 can generate front and rear beams (i.e., front beam and rear beam); when the switch switching unit 400 switches the circularly polarized antenna 100b and the circularly polarized antenna 100c to be electrically connected to the first input port I1 and the second input port I2 of the phase adjustment unit 300, the antenna device 1000 can generate left and right beams (i.e., left beam and right beam); when the switch switching unit 400 switches the circularly polarized antenna 100a and the circularly polarized antenna 100c to be electrically connected to the first input port I1 and the second input port I2 of the phase adjustment unit 300, the antenna device 1000 can generate diagonal beams (i.e., upper left corner beam and lower right corner beam).

[0145] In some embodiments, as shown in FIG. 5, the first input port I1 is electrically connected to a satellite communication transceiver 510, and the satellite communication transceiver 510 can be a sky net satellite communication transceiver or a Tianhong satellite communication transceiver; the second input port I2 is electrically connected to a cellular communication transceiver 520. In this way, the above-mentioned antenna device 1000 can not only perform satellite communication to meet the satellite communication needs of the vehicle in different orientations, but also perform cellular communication to meet the cellular communication needs of the vehicle in different orientations, and has good communication effect for ground station, remote control and other scenes. ​

[0146] In some embodiments, the vehicle can determine the orientation of the vehicle body through GNSS positioning and gyroscopes and other sensors, so as to align the beam of the antenna device 1000 to the satellite.

[0147] In order to reduce the signal interference between different ports of the phase adjustment unit 300, in some embodiments, as shown in FIG. 6, the phase adjustment unit 300 is a 3dB bridge. ​

[0148] Of course, in addition to the 3dB bridge, the phase adjustment unit 300 can also be a phase shifter and the like.

[0149] In order to improve the isolation effect between different signal channels in the switch switching unit 400, in some embodiments, as shown in FIG. 7, the switch switching unit 400 is a Wilkinson power divider. ​ ​​As shown, the switch switching unit 400 is a double-pole four-throw switch, which has two input contacts 410 and four output contacts 420, the two input contacts 410 are connected with the first input port I1 and the second input port I2 one by one respectively, and the three output contacts 420 are electrically connected with the three circularly polarized antennas 100 one by one. When the double-pole four-throw switch is switched to a certain position, it can effectively isolate other unselected signal paths, thereby reducing the mutual interference between signals.

[0150] The number of the circularly polarized antennas 100 in the antenna device 1000 in the embodiment of the present application is not limited to three. For example, the number of the circularly polarized antennas 100 can also be two, and the two circularly polarized antennas 100 can be arranged side by side along the length direction L of the vehicle body 2000, or can be arranged side by side along the width direction W of the vehicle body 2000. For another example, the number of the circularly polarized antennas 100 can also be four, and the four circularly polarized antennas 100 are arranged in a square shape, i.e. 2*2 array.

[0151] ​ Fig. 4 is a schematic view of the division of the direction sector of the vehicle in the embodiment of the present application, ​ Fig. 5 is a schematic view of the change of the heading angle of the vehicle when turning in the embodiment of the present application.

[0152] In order to solve the problem of beam switching of the antenna device 1000 when the vehicle is moving, in some embodiments, the vehicle heading is refreshed every 100 ms and the antenna switching is performed once, and according to the calculation of turning at a speed of 30 km / h, the angle change of the vehicle heading is about 5°, as shown in Fig. 6. ​ As shown in Fig. 7, the vehicle is divided into four 90° sectors in front, back, left and right, and the beam width of the antenna device 1000 is greater than 100°, so that the smooth switching of the circularly polarized antennas 100 in the antenna device 1000 does not drop.

[0153] As shown in Fig. 8, when the vehicle moves at a speed of 30 km / h, the angle change of the vehicle heading is about 5°, which can be derived by the following process, as shown in Fig. 9. ​ As shown in Fig. 9, when the vehicle moves at a speed of 30 km / h, the distance covered in 100 ms is: 30 km / h*100 ms≈0.83 m; the circumference of the circle = 2*3.14*10 m = 62.8 m, so the angle phi of the vehicle = 360*0.83 / 62.8≈5°.

[0154] ​ Fig. 10 is a comparison diagram of the single antenna (having one circularly polarized antenna 100) and the antenna device 1000 in the embodiment of the present application (i.e. multiple circularly polarized antennas 100), ​ Fig. 11 is a comparison diagram of the beam width of the single antenna and the antenna device 1000 in the embodiment of the present application, ​Fig. 1 is a diagram showing the communication effect of the antenna device 1000 at different beam elevation angles according to an embodiment of the present application.

[0155] Fig. 2 is a diagram showing the antenna gain of the antenna device 1000 at different beam elevation angles according to an embodiment of the present application. ​ ​ As can be seen from Fig. 2, the antenna gain of the antenna device 1000 at the beam elevation angle of 70° (i.e. 20°) is increased by 3dB max. ​ As can be seen from Fig. 2, the antenna gain of the antenna device 1000 at the beam elevation angle of 10° (theta=80°) satisfies the satellite communication requirement, and the beam width of the antenna device 1000 is wider, and the signal coverage is wider.

[0156] ​ Fig. 3 is a diagram showing the comparison of the antenna gain of the antenna device 1000 and the existing cellular antenna according to an embodiment of the present application. In Fig. 3, ​ (a) of Fig. 3 shows the comparison of the antenna gain at the beam elevation angle of 20° (theta=70°) and the azimuth angle phi from 0° to 360°, ​ (b) of Fig. 3 shows the comparison of the antenna gain at the beam elevation angle of 10° (theta=80°) and the azimuth angle phi from 0° to 360°; ​ (c) of Fig. 3 shows the comparison of the antenna gain at the beam elevation angle of 0° (theta=90°, i.e. the horizontal plane) and the azimuth angle phi from 0° to 360°. As shown in Fig. 3, ​ taking the cellular Band 3 as an example, the antenna gain of the antenna device 1000 is obviously increased in the low elevation angle area (70°-90°) compared with the original cellular antenna (IFA / IL, etc.).

[0157] ​ Fig. 4 is a diagram showing the internal structure of the antenna device 1000 according to another embodiment of the present application. As shown in Fig. 4, ​ the antenna device 1000 comprises a shell 600, and a second circuit board 750, an antenna array 200, a cellular low-frequency antenna 710 and a cellular high-frequency antenna 720 which are all arranged in the shell 600. The antenna array 200, the cellular low-frequency antenna 710 and the cellular high-frequency antenna are arranged on a bearing substrate of the second circuit board 750. The number of the cellular low-frequency antenna 710 can be two, and the number of the cellular high-frequency antenna 720 can be four.

[0158] In some embodiments, as shown in Fig. 5, ​ the antenna device 1000 further comprises a power supply battery 730 which is arranged on the bearing substrate of the second circuit board 750 and is used for supplying power to the antenna array 200, the cellular low-frequency antenna 710 and the cellular high-frequency antenna 720.

[0159] In some embodiments, as shown in Fig. 6, ​ ​As shown, the antenna device 1000 further includes a connector 740 mounted on the shell wall of the shell 600.

[0160] Although the description of the present application will be introduced in combination with some embodiments, it does not mean that the features of the present application are limited to the embodiments. On the contrary, the embodiments introduced in combination with the present application are intended to cover other options or modifications that can be extended based on the claims of the present application. In order to provide a deep understanding of the present application, many specific details will be included in the above description. The present application can also be implemented without using these details. In addition, in order to avoid confusion or obscure the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0161] In the embodiments of the present application, the terms "first", "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features.

[0162] In the embodiments of the present application, "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0163] In the description of the embodiments of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting" should be understood in a broad sense, for example, "connecting" can be detachable connection, or can be non-detachable connection; can be direct connection, or can be indirect connection through intermediate medium. The orientation language mentioned in the embodiments of the present application, such as "upper", "lower", "left", "right", "inner", "outer" and the like, is only the direction of the drawing, therefore, the orientation language used is to better, more clearly illustrate and understand the embodiments of the present application, and is not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the embodiments of the present application. "Multiple" means at least two.

[0164] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A circularly polarized antenna, characterized by, The circularly polarized antenna comprises: a ground plate (1); a dielectric plate (2) arranged apart from the ground plate (1) along the thickness direction of the dielectric plate (2); a plurality of first radiating arms (31) arranged on the dielectric plate (2) and constituting at least one cross-dipole (30), each first radiating arm (31) having a first end arranged close to a central region (21) of the dielectric plate (2) and a second end arranged close to an edge (22) of the dielectric plate (2); a plurality of parasitic radiating arms (32) distributed at the edge (22) of the dielectric plate (2) along the circumferential direction of the dielectric plate (2), each parasitic radiating arm (32) being coupled to the adjacent first radiating arm (31), each parasitic radiating arm (32) having a ground end (3201) connected to the ground plate (1) and an open end (3202) located at the edge (22) of the dielectric plate (2), the cross-sectional area of the parasitic radiating arm (32) at the ground end (3201) being smaller than the cross-sectional area of the parasitic radiating arm (32) at the open end (3202); a feeding unit (4) for feeding each first radiating arm (31).

2. The circularly polarized antenna according to claim 1, wherein the parasitic radiating arm (32) comprises a first arm segment (321) and a second arm segment (322), the second arm segment (322) being connected between the first arm segment (321) and the ground plate (1), the cross-sectional area of the second arm segment (322) being smaller than the cross-sectional area of the first arm segment (321), the open end (3202) being located at the first arm segment (321), and the ground end (3201) being located at the second arm segment (322).

3. The circularly polarized antenna according to claim 2, wherein the first arm segment (321) and the second arm segment (322) are both rectangular plate structures, the length of the short side of the second arm segment (322) being smaller than the length of the long side of the first arm segment (321), and the short side of the second arm segment (322) being connected to the middle of the long side of the first arm segment (321).

4. The circularly polarized antenna according to claim 1 or 2, wherein the dielectric plate (2) is a polygonal plate having a plurality of corners (23), each parasitic radiating arm (32) being located at a corresponding corner (23) and forming a radiating arm group (33) with the adjacent first radiating arm (31), in the radiating arm group (33), the parasitic radiating arm (32) and the first radiating arm (31) are dimensionally overlapped in the length direction of the first radiating arm (31) and in the width direction of the first radiating arm (31).

5. The circularly polarized antenna according to any one of claims 1 to 3, wherein The dielectric plate (2) is a polygonal plate and has a plurality of edges (22), each of the parasitic radiation arms (32) is located at a corresponding edge (22) and forms a radiation arm group (33) with the adjacent first radiation arm (31); in the radiation arm group (33), in the length direction of the first radiation arm (31), the size of the parasitic radiation arm (32) is smaller than the size of the first radiation arm (31), and the parasitic radiation arm (32) completely overlaps the first radiation arm (31) in size.

6. The circularly polarized antenna of any one of claims 1-5, wherein, Each of the first radiation arms (31) is provided with a notch (311) at the first end.

7. The circularly polarized antenna of any one of claims 1-6, wherein, The dielectric plate (2) comprises a first plate surface (2a) and a second plate surface (2b) arranged opposite to each other, the number of the first radiation arms (31) is four, the four first radiation arms (31) are arranged around the center region (21) of the dielectric plate (2) and form two cross dipoles (30), one cross dipole (30) is arranged on the first plate surface (2a) and the other cross dipole (30) is arranged on the second plate surface (2b), and the first ends of the two first radiation arms (31) in each cross dipole (30) are connected by a phase delay line (34); The feeding unit (4) is a coaxial cable and comprises an outer conductor (41), an inner conductor (42), and an insulator (43) filled between the outer conductor (41) and the inner conductor (42), the coaxial cable extends to the center region (21) of the dielectric plate (2), the outer conductor (41) is electrically connected with one of the first radiation arms (31) located on the second plate surface (2b), the inner conductor (42) passes through the dielectric plate (2) and is electrically connected with one of the first radiation arms (31) located on the first plate surface (2a), and the two first radiation arms (31) electrically connected with the inner conductor (42) and the outer conductor (41) respectively have the same extension direction.

8. The circularly polarized antenna of claim 7, wherein, On the first plate surface (2a), the first end of one of the first radiation arms (31) is provided with a first connecting flange (312) which extends into the area surrounded by the phase delay line (34) and abuts against the inner conductor (42); On the second plate surface (2b), the first end of one of the first radiation arms (31) is provided with a second connecting flange (313) which extends into the area surrounded by the phase delay line (34) and abuts against the outer conductor (41).

9. An antenna device, characterized by An antenna array (200) is provided, the antenna array (200) comprises a plurality of circularly polarized antennas (100) according to any one of claims 1-8.

10. The antenna device of claim 9, wherein, The number of the circularly polarized antennas (100) is three, and the three circularly polarized antennas (100) are arranged in a triangle or L shape. The antenna device further comprises a phase adjusting unit (300) and a switch switching unit (400). The phase adjusting unit (300) has a first input port (I1), a second input port (I2), a first output port (P1), and a second output port (P2), the first input port (I1) and the second input port (I2) are respectively used for electrical connection with a communication transceiver; the first output port (P1) and the second output port (P2) are respectively used for outputting signals with a phase difference of 90°; The switch switching unit (400) is respectively electrically connected with the first input port (I1), the second input port (I2), and the three circularly polarized antennas (100), and the switch switching unit (400) is used for electrically connecting the first input port (I1) and the second input port (I2) with any two of the circularly polarized antennas (100) one by one.

11. The antenna device according to claim 10, wherein The phase adjusting unit (300) is a 3dB electrical bridge; And / or, the switch switching unit (400) is a double-pole four-throw switch, the double-pole four-throw switch has two input contacts (410) and four output contacts (420), the two input contacts (410) are respectively connected with the first input port (I1) and the second input port (I2) one by one, and the three output contacts (420) are respectively electrically connected with the three circularly polarized antennas (100) one by one.

12. The antenna device according to claim 10 or 11, wherein The first input port (I1) is used for electrical connection with a satellite communication transceiver (510), and the second input port (I2) is used for electrical connection with a cellular communication transceiver (520).

13. A vehicle characterized by comprising: A vehicle comprising a vehicle body (2000) and the antenna device (1000) according to any one of claims 9-12, the antenna device (1000) being arranged on the vehicle body (2000).

14. The vehicle according to claim 13, wherein The antenna device (1000) is arranged on the top of the vehicle body (2000).

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