Antenna

Abstract

The invention discloses an antenna, which comprises at least one antenna unit, the antenna unit comprises a first sub-antenna unit and a plurality of second sub-antenna units, and the plurality of second sub-antenna units are uniformly distributed around the first sub-antenna unit, the upper limit value of the first working frequency band of the first sub-antenna unit is smaller than the lower limit value of the second working frequency band of the second sub-antenna unit, and the height of the first sub-antenna unit is smaller than that of the second sub-antenna unit; the frequency corresponding to the radiation zero point of the first sub-antenna unit is smaller than the lower limit value of the second working frequency band, and the frequency corresponding to the radiation zero point of the second sub-antenna unit is larger than the upper limit value of the first working frequency band.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular, to an antenna. Background Art

[0002] In the field of mobile communications, adjacent frequency bands at the same layer are allocated to different operators.

[0003] For example, the 790 - 862 MHz frequency band is allocated to one operator, while the 880 - 960 MHz frequency band is allocated to another operator. Although there are corresponding broadband array antennas that can cover the 790 - 960 MHz frequency band, since there is only one set of ports and it can only be connected to the transceiver of one operator, it cannot be shared by two operators. Although the above problem can be solved by using two independent antenna arrays, overall, this will result in an overly large array size, and it is difficult for operators to find enough space to install the array. Therefore, a compact antenna array with two sets of ports is needed to support two operators simultaneously.

[0004] However, when integrating two sub - antenna units with adjacent frequency bands in an antenna array, since the two frequency bands are extremely close, the isolation between the antenna units will become poor, and further, the radiation pattern will be distorted.

[0005] In view of this, how to improve the isolation between two sub - antenna units with adjacent frequency bands has become a technical problem to be solved urgently. Summary of the Invention

[0006] Embodiments of the present invention provide an antenna to solve the technical problem of low isolation between two sub - antenna units with adjacent frequency bands in the prior art.

[0007] In a first aspect, to solve the above - mentioned technical problem, embodiments of the present invention provide an antenna, including:

[0008] At least one antenna unit, where the antenna unit includes a first sub - antenna unit and a plurality of second sub - antenna units, the plurality of second sub - antenna units are evenly distributed around the first sub - antenna unit, the upper limit value of the first operating frequency band of the first sub - antenna unit is less than the lower limit value of the second operating frequency band of the second sub - antenna unit, and the height of the first sub - antenna unit is less than the height of the second sub - antenna unit;

[0009] The frequency corresponding to the radiation null of the first sub - antenna unit is less than the lower limit value of the second operating frequency band, and the frequency corresponding to the radiation null of the second sub - antenna unit is greater than the upper limit value of the first operating frequency band.

[0010] A possible implementation, the antenna unit further includes a ground plane located on one side of the first sub-antenna unit and not in contact with the first sub-antenna unit. The first sub-antenna unit includes:

[0011] A radiation plate located on one side of the ground plane;

[0012] The size of the radiation plate is greater than a preset size; wherein, the preset size is the size of the radiation plate when the frequency corresponding to the radiation null point of the first sub-antenna unit is at the lower limit value of the second operating frequency band; or, the preset size is the size of the radiation plate in the first sub-antenna unit with the third operating frequency band, the bandwidth of the third operating frequency band is the same as the bandwidth of the first operating frequency band, and the upper limit value of the third operating frequency band is the lower limit value of the second operating frequency band.

[0013] A possible implementation, the first sub-antenna unit further includes:

[0014] A printed circuit board located between the radiation plate and the ground plane; there is a first air layer between the printed circuit board and the radiation plate, and a second air layer between the printed circuit board and the ground plane; a metal layer is provided on the side of the printed circuit board close to the radiation plate, the metal layer has a ring-shaped gap penetrating through the thickness direction, and a feeding network is provided on the side of the printed circuit board away from the radiation plate;

[0015] The feeding network includes a plurality of non-connected feeding structures, and two relatively arranged feeding structures receive feeding signals with the same amplitude but different phases; the plurality of feeding structures are symmetrically arranged with respect to the center of the ring-shaped gap in the orthographic projection on the printed circuit board, and the ring-shaped gap overlaps with the feeding structures;

[0016] A first liquid crystal structure covers the feeding network; the first liquid crystal structure is used to adjust the dielectric constant corresponding to the feeding network, so that the radiation null point of the first sub-antenna unit is less than the lower limit value of the second operating frequency band.

[0017] A possible implementation, the shape of the ring-shaped gap is square;

[0018] The feeding structure includes a first strip-shaped structure, and the first strip-shaped structure intersects with one side of the ring-shaped gap.

[0019] A possible implementation, the feeding structure further includes:

[0020] A second strip-shaped structure and a third strip-shaped structure are located on both sides of one side of the ring-shaped gap and are parallel to each other, and the first strip-shaped structure is connected between the first strip-shaped structure and the third strip-shaped structure;

[0021] The second strip structure is located within the orthographic projection of the annular gap on the printed circuit board, and the third strip structure is located outside the orthographic projection of the annular gap on the printed circuit board;

[0022] The length of the second strip structure is less than the length of the third strip structure, and the length of the third strip structure is less than the side length of the annular gap.

[0023] A possible implementation, the second sub-antenna unit includes:

[0024] A first radiation arm and a second radiation arm, the first radiation arm and the second radiation arm are on the same straight line and do not overlap with the first sub-antenna unit;

[0025] A balun feeding structure, the balun feeding structure includes a grounding structure and a feeding signal line, the grounding structure is grounded and is connected to the first radiation arm and the second radiation arm, and the feeding signal line is coupled to the second radiation arm;

[0026] The feeding signal line includes a first branch, the opening direction of the first branch is away from the second radiation arm, the length of the first branch is greater than a preset length, and the preset length is the length corresponding to the first branch when the radiation null frequency of the second sub-antenna unit is the upper limit value of the first operating frequency.

[0027] A possible implementation, the second sub-antenna unit further includes:

[0028] A first support structure and a second support structure, the first support structure is connected between the first radiation arm and the floor, and the second support structure is connected between the second radiation arm and the floor; the orthographic projections of the first support structure and the second support structure on the floor are arranged in parallel;

[0029] The side of the first support structure away from the second support structure is entirely copper-clad to form the grounding structure connected to the first radiation arm; the side of the second support structure away from the first support structure is entirely copper-clad to form the grounding structure connected to the second radiation arm, and the feeding signal line is arranged on the side of the second support structure close to the first support structure and is coupled to the second radiation arm;

[0030] A second liquid crystal structure, covering the first branch; the second liquid crystal structure is used to change the equivalent dielectric constant at the position corresponding to the first branch, so that the radiation null of the second sub-antenna unit is greater than the upper limit value of the first operating frequency band;

[0031] The second liquid crystal structure is arranged on the side of the second support structure close to the first support structure or arranged inside the second support structure.

[0032] A possible implementation, the feed signal line further includes:

[0033] A feeder line, one end of the feeder is coupled to the second radiation arm, and the other end of the feeder is connected to a feed signal input terminal; the first stub is located on one side of the feeder line and is connected to the feeder line;

[0034] A second stub and a third stub are located on the other side of the feeder line and are connected to the feeder line; the opening directions of the second stub and the third stub are opposite, and the lengths of the second stub and the third stub are 1 / 4 of the wavelength of the electromagnetic wave radiated by the second sub - antenna unit.

[0035] A possible implementation, the orthographic projection shape of the plurality of second sub - antenna units on the floor matches the orthographic projection shape of the radiation plate on the floor;

[0036] The feed signals received by two relatively arranged second sub - antenna units have the same amplitude and the same phase.

[0037] A possible implementation, the total number of the plurality of second sub - antenna units is four. Description of the Drawings

[0038] Figure 1 It is a schematic structural diagram of an antenna provided by an embodiment of the present invention;

[0039] Figure 2 It is a three - dimensional schematic diagram of an antenna unit provided by an embodiment of the present invention;

[0040] Figure 3 It is a current density distribution diagram of the antenna unit when the first sub - antenna unit is excited at 870 MHz provided by an embodiment of the present invention;

[0041] Figure 4 It is a current density distribution diagram of the antenna unit when the first sub - antenna unit is excited at 910 MHz provided by an embodiment of the present invention;

[0042] Figure 5 It is a top view of the first sub - antenna unit provided by an embodiment of the present invention;

[0043] Figure 6 It is an antenna gain diagram of the first sub - antenna unit provided by an embodiment of the present invention;

[0044] Figure 7 It is a schematic structural diagram of the first sub - antenna unit provided by an embodiment of the present invention;

[0045] Figure 8The bottom view of a printed circuit board provided by an embodiment of the present invention;

[0046] Figure 9 The bottom view of another printed circuit board provided by an embodiment of the present invention;

[0047] Figure 10 The structural schematic diagram of another first sub - antenna unit provided by an embodiment of the present invention;

[0048] Figure 11 The antenna gain diagram corresponding to a first sub - antenna unit provided by an embodiment of the present invention;

[0049] Figure 12 The top view of an antenna unit provided by an embodiment of the present invention;

[0050] Figure 13 The top view of another antenna unit provided by an embodiment of the present invention;

[0051] Figure 14 The three - dimensional schematic diagram of a second sub - antenna unit provided by an embodiment of the present invention;

[0052] Figure 15 The schematic diagram of a feed signal line provided by an embodiment of the present invention;

[0053] Figure 16 The antenna gain diagram of a second sub - unit antenna provided by an embodiment of the present invention;

[0054] Figure 17 The structural schematic diagram of another feed signal line provided by an embodiment of the present invention;

[0055] Figure 18 The cross - sectional view of a second support structure along the extension direction of the first branch provided by an embodiment of the present invention;

[0056] Figure 19 The antenna gain diagram of another second sub - antenna unit provided by an embodiment of the present invention.

[0057] Reference numerals:

[0058] Antenna unit 1, first sub-antenna unit 11, second sub-antenna unit 12, floor 13, radiation plate 111, annular slit F, printed circuit board 112, first air layer 113, second air layer 114, feeding network 115, feeding structure 1151, probe P, first strip structure 11511, second strip structure 11512, third strip structure 11513, first liquid crystal structure 116, first radiation arm 121, second radiation arm 122, balun feeding structure 123, feeding signal line 1231, first branch 12311, feeding wire 12312, second branch 12313, third branch 12314, first support structure 124, second support structure 125, second liquid crystal structure 126. Detailed implementation manners

[0059] An embodiment of the present invention provides an antenna, which is used to solve the technical problem that the isolation degree between two sub-antenna units with adjacent frequency bands is not high in the prior art.

[0060] It should be understood that the specific structures and functional details disclosed in the embodiments of the present invention are only representative and are for the purpose of describing the exemplary embodiments of the present application. However, the present application can be specifically implemented in many alternative forms or combined forms and should not be construed as being limited only to the embodiments described herein.

[0061] In the description of the present application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise specified, the meaning of "a plurality" is two or more. Additionally, the term "comprising" and any variation thereof are intended to cover non-exclusive inclusion.

[0062] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "a" and "an" used herein are also intended to include the plural. It should also be understood that the terms "comprising" and / or "including" specify the presence of the stated features, integers, steps, operations, units, and / or components, and do not exclude the presence or addition of one or more other features, integers, steps, operations, units, components, and / or their combinations.

[0063] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings represent the same or similar structures, and thus their repeated descriptions will be omitted. The words expressing positions and directions described in the present invention are illustrative with reference to the drawings, but can be changed as needed, and all changes are included within the protection scope of the present invention. The drawings of the present invention are only used to illustrate the relative positional relationship and do not represent the actual scale.

[0064] It should be noted that specific details are set forth in the following description to facilitate a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below. The subsequent description of the specification is the preferred embodiment for implementing the present application, but the description is for the purpose of explaining the general principles of the present application and is not intended to limit the scope of the present application. The protection scope of the present application shall be determined by the scope defined by the appended claims.

[0065] The following specifically describes an antenna provided by an embodiment of the present invention in conjunction with the accompanying drawings.

[0066] Please refer to Figure 1 and Figure 2 , Figure 1 which is a schematic structural diagram of an antenna provided by an embodiment of the present invention, Figure 2 and which is a three-dimensional schematic diagram of an antenna unit provided by an embodiment of the present invention. The antenna includes:

[0067] At least one antenna unit 1, where the antenna unit 1 includes a first sub-antenna unit 11 and a plurality of second sub-antenna units 12. The plurality of second sub-antenna units 12 are evenly distributed around the first sub-antenna unit 11. The upper limit value of the first operating frequency band of the first sub-antenna unit 11 is less than the lower limit value of the second operating frequency band of the second sub-antenna unit 12, and the height h1 of the first sub-antenna unit 11 is less than the height h2 of the second sub-antenna unit 12;

[0068] The frequency corresponding to the radiation null point of the first sub-antenna unit 11 is less than the lower limit value of the second operating frequency band, and the frequency corresponding to the radiation null point of the second sub-antenna unit 12 is greater than the upper limit value of the first operating frequency band.

[0069] The antenna can include one antenna unit 1, or can also be detailed Figure 1Including multiple antenna units 1 as such, and the multiple antenna units 1 form an array. The first sub-antenna unit 11 and the second sub-antenna unit 12 are independently fed, that is, each corresponds to a feeding interface.

[0070] Since the first operating frequency band of the first sub-antenna unit 11 is adjacent to the second operating frequency band of the second sub-antenna unit 12, if the distance between the first sub-antenna unit 11 and the second sub-antenna unit 12 is set to be small, it is easy to increase the mutual coupling between the first operating frequency band and the second operating frequency band, thereby reducing the isolation degree between the first sub-antenna unit 11 and the second sub-antenna unit 12; if the distance between the first sub-antenna unit 11 and the second sub-antenna unit 12 is increased to reduce the mutual coupling between the first operating frequency band and the second operating frequency band, it will increase the size of the antenna unit 1, and further increase the size of the entire antenna.

[0071] It should be noted that the adjacent first operating frequency band and the second operating frequency band mean that the frequency bands of the first operating frequency band and the second operating frequency band do not overlap with each other, and the second operating frequency band is less than 1.6 times that of the first operating frequency band. For example, if the first operating frequency band is 790 MHz to 862 MHz and the second operating frequency band is 880 MHz to 960 MHz, 1.6 times of 790 MHz to 862 MHz is 1264 MHz to 1379.2 MHz. Obviously, 880 MHz to 960 MHz is less than 1264 MHz to 1379.2 MHz. Therefore, the first operating frequency band 790 MHz to 862 MHz is adjacent to the second operating frequency band 880 MHz to 960 MHz.

[0072] Please refer to Figure 3 and Figure 4 , Figure 3 is a current density distribution diagram of the antenna unit when the first sub-antenna unit is excited at 870 MHz provided by the embodiment of the present invention. Figure 4 is a current density distribution diagram of the antenna unit when the first sub-antenna unit is excited at 910 MHz provided by the embodiment of the present invention. It can be seen from Figure 3 that when the first sub-antenna unit 11 is excited at 870 MHz, there will be an induced current in the second sub-antenna unit 12. It can be seen from Figure 4 that when the first sub-antenna unit 11 is excited at 910 MHz (that is, exceeding the radiation null point 880 MHz), the induced current in the second sub-antenna unit 12 is very weak and almost non-existent. Therefore, by making the frequency corresponding to the radiation null point of the first sub-antenna unit 11 less than the lower limit value of the second operating frequency band and the frequency corresponding to the radiation null point of the second sub-antenna unit 12 greater than the upper limit value of the first operating frequency band, the mutual coupling between the first sub-antenna unit 11 and the second sub-antenna unit 12 can be reduced, and the isolation degree between the first sub-antenna unit 11 and the second sub-antenna unit 12 can be improved.

[0073] In the present invention, by making the frequency corresponding to the radiation null point of the first sub - antenna unit 11 less than the lower limit value of the second operating frequency band, the first sub - antenna unit 11 radiates electromagnetic waves in the range less than the lower limit value of the second operating frequency band. By making the frequency corresponding to the radiation null point of the second sub - antenna unit 12 greater than the upper limit value of the first operating frequency band, the second sub - antenna unit 12 radiates electromagnetic waves in the range greater than the upper limit value of the first operating frequency band, thereby reducing the mutual coupling between the first operating frequency band and the second operating frequency band. In this way, it is not necessary to increase the distance between the first sub - antenna unit 11 and the second sub - antenna unit 12 to reduce the mutual coupling between the first operating frequency band and the second operating frequency band. Thus, while improving the isolation degree between the first sub - antenna unit 11 and the second sub - antenna unit 12, the size of the antenna unit 1 can be effectively reduced, realizing a compact design of the antenna. And by surrounding the first sub - antenna unit 11 with a plurality of second sub - antenna units 12 and making the height h1 of the first sub - antenna unit 11 less than the height h2 of the second sub - antenna unit 12, it is possible to prevent the first sub - antenna unit 11 from blocking the second sub - antenna unit 12, thereby further improving the isolation degree between the first sub - antenna unit 11 and the second sub - antenna unit 12.

[0074] Please continue to refer to Figure 2 The antenna unit 1 further includes a ground plane 13 located on one side of the first sub - antenna unit 11 and having no contact with the first sub - antenna unit 11. Please refer to Figure 5 FIG. is a top view of a first sub - antenna unit provided by an embodiment of the present invention. The first sub - antenna unit 11 includes:

[0075] A radiation plate 111 located on one side of the ground plane 13 ( Figure 5 not shown); the shape of the radiation plate 111 can be a quadrilateral as shown in Figure 5 . The quadrilateral can be a square or a rectangle. The shape of the radiation plate 111 can also be a circle, an ellipse, etc., and is not specifically limited. The radiation plate 111 is composed of a metal plate, for example, it can be an aluminum plate.

[0076] The size of the radiation plate 111 is greater than a preset size; wherein, the preset size is the size of the radiation plate 111 when the frequency corresponding to the radiation null point of the first sub - antenna unit 11 is at the lower limit value of the second operating frequency band; or, the preset size is the size of the radiation plate 111 in the first sub - antenna unit 11 with the operating frequency band being the third operating frequency band. The bandwidth of the third operating frequency band is the same as the bandwidth of the first operating frequency band, and the upper limit value of the third operating frequency band is the lower limit value of the second operating frequency band. When designing the first sub - antenna unit 11, the above - mentioned preset size can be determined by simulating the first sub - antenna unit 11 based on the lower limit value of the second operating frequency band or the center frequency of the third operating frequency band.

[0077] If the radiation plate 111 is square, the size of the radiation plate 111 refers to the side length of the radiation plate 111; if the radiation plate 111 is rectangular, the size of the radiation plate 111 refers to the length and width of the radiation plate 111; if the radiation plate 111 is circular, the size of the radiation plate 111 refers to the radius of the radiation plate 111. When the radiation plate 111 is of other shapes, the size of the radiation plate 111 can be deduced by analogy, and will not be elaborated here one by one.

[0078] Please refer to Figure 6 which is the antenna gain diagram of a first sub-antenna unit provided by an embodiment of the present invention. Figure 6 The antenna gain curves corresponding to different sizes of the radiation plate 111 are shown, and the lowest point of the antenna gain curve is the corresponding radiation null point; among them, the shape of the radiation plate 111 is square, and PL1 in the figure represents the side length of the radiation plate 111.

[0079] From Figure 6 it can be seen that by adjusting the size (side length) of the radiation plate 111, the position of the radiation null point can be changed. As the side length of the radiation plate 111 increases, the radiation null point moves towards the low-frequency direction. Therefore, by covering the size of the radiation plate 111, the radiation null point of the first sub-antenna unit 11 can be moved towards the low-frequency direction. When the size of the radiation plate 111 is adjusted to be greater than the preset size, the radiation null point of the first sub-antenna unit 11 can be moved to a range less than the lower limit value of the second operating frequency band, so that the first sub-antenna unit 11 can radiate electromagnetic waves only within a range less than the lower limit value of the second operating frequency band, thereby improving the isolation between the first sub-antenna unit 11 and the second sub-antenna unit 12.

[0080] In the embodiment provided by the present invention, by making the size of the radiation plate 111 greater than the preset size; where the preset size is the size of the radiation plate 111 when the frequency corresponding to the radiation null point of the first sub-antenna unit 11 is at the lower limit value of the second operating frequency band; or, the preset size is the size of the radiation plate 111 in the first sub-antenna unit 11 whose operating frequency band is the third operating frequency band, the bandwidth of the third operating frequency band is the same as the bandwidth of the first operating frequency band, and the upper limit value of the third operating frequency band is the lower limit value of the second operating frequency band. The first sub-antenna unit 11 can radiate electromagnetic waves within a frequency range corresponding to less than the lower limit value of the second operating frequency band, thereby reducing the mutual coupling between the first operating frequency band and the second operating frequency band.

[0081] Please refer to Figure 7 which is a schematic structural diagram of a first sub-antenna unit provided by an embodiment of the present invention. The first sub-antenna unit 11 further includes:

[0082] The printed circuit board 112 is located between the radiation plate 111 and the ground plane 13; there is a first air layer 113 between the printed circuit board 112 and the radiation plate 111, and a second air layer 114 between the printed circuit board 112 and the ground plane 13; a metal layer 1121 is disposed on the surface of the printed circuit board 112 close to the radiation plate 111, and the metal layer 1121 has an annular gap F penetrating in the thickness direction, and a feeding network 115 is disposed on the surface of the printed circuit board 112 far from the radiation plate 111; support columns ( Figure 7 not shown in the figure) may be provided between the printed circuit board 112 and the radiation plate 111 to form a first air layer 113 between the printed circuit board 112 and the radiation plate 111; support columns having probes P may be provided between the printed circuit board 112 and the ground plane 13 to form a second air layer 114 between the printed circuit board 112 and the ground plane 13, and the probes P are connected to the feeding network 115, and the probes P are used for feeding the feeding network 115. The shape of the annular gap F may be a quadrilateral, such as a rectangle or a square, or may be a circle, an ellipse, etc., and is not specifically limited; the feeding network 115 may be disposed on the surface of the printed circuit board 112 close to the radiation plate 111, or may be disposed on the surface far from the radiation plate 111, and is not specifically limited.

[0083] The feeding network 115 includes a plurality of non-connected feeding structures 1151, and two relatively disposed feeding structures 1151 receive feeding signals with the same amplitude but different phases; the plurality of feeding structures 1151 are symmetrically disposed about the center of the annular gap F in the orthographic projection on the printed circuit board 112, and the annular gap F overlaps with the feeding structures 1151. The first sub-antenna unit 11 may be a single-polarization sub-antenna unit. At this time, the feeding network 115 includes two relatively disposed feeding structures 115; the first sub-antenna unit 11 may also be a dual-polarization sub-antenna unit. At this time, the feeding network 115 includes four feeding structures 1151, and two relatively disposed feeding structures 1151 form a low-frequency dipole, and two adjacent feeding structures 115 receive feeding signals with the same amplitude but the same phase to form a ±45° dual-polarization sub-antenna unit. Whether the first sub-antenna unit 11 realizes single polarization or dual polarization, the basic structures of the two feeding structures 115 constituting the low-frequency dipole in the first sub-antenna unit 11 are the same. Correspondingly, two relatively disposed second sub-antenna units 12 may form a high-frequency dipole to realize single polarization. If there are 4 second sub-antenna units 12, 2 high-frequency dipoles may be formed to realize dual polarization. The specific structure of the first sub-antenna unit 12 will be introduced in subsequent embodiments and will not be elaborated here.

[0084] As Figure 5 shown, the shape of the annular gap F of the radiation plate 111 is a square; please refer to Figure 8A bottom view of a printed circuit board provided by an embodiment of the present invention. The feeding structure 1151 includes a first strip-shaped structure 11511, and the first strip-shaped structure 11511 intersects with one side of the annular slit F.

[0085] It should be noted that, for the convenience of observation, the annular slit F is orthogonally projected onto the side of the printed circuit board 112 away from the radiation plate.

[0086] In the embodiment provided by the present invention, by making the first strip-shaped structure 11511 intersect with one side of the annular slit F, an induced current can be generated on the radiation plate 111, so that the radiation plate 111 generates electromagnetic waves radiated outward in a direction away from the printed circuit board 112.

[0087] Please refer to Figure 9 A bottom view of another printed circuit board provided by an embodiment of the present invention. The feeding structure 1151 further includes:

[0088] A second strip-shaped structure 11512 and a third strip-shaped structure 11513, which are located on both sides of one side of the annular slit F and are arranged in parallel. The first strip-shaped structure 11511 is connected between the first strip-shaped structure 11511 and the third strip-shaped structure 11513;

[0089] The second strip-shaped structure 11512 is located within the orthographic projection of the annular slit F on the printed circuit board 112, and the third strip-shaped structure 11513 is located outside the orthographic projection of the annular slit F on the printed circuit board 112;

[0090] The length L1 of the second strip-shaped structure 11512 is less than the length L2 of the third strip-shaped structure 11513, and the length of the third strip-shaped structure 11513 is less than the side length of the annular slit F.

[0091] By arranging the second strip-shaped structure 11512 and the third strip-shaped structure 11513 connected to both ends of the first strip-shaped structure 11511, making the second strip-shaped structure 11512 located within the orthographic projection of the annular slit F on the printed circuit board 112, the third strip-shaped structure 11513 located outside the orthographic projection of the annular slit F on the printed circuit board 112, the length L1 of the second strip-shaped structure 11512 being less than the length L2 of the third strip-shaped structure 11513, and the length of the third strip-shaped structure 11513 being less than the side length of the annular slit F, the impedance matching of the feeding network 115 can be achieved by using the second strip-shaped structure 11512 and the third strip-shaped structure 11513.

[0092] Please refer to Figure 10 A schematic structural diagram of another first sub-antenna unit provided by an embodiment of the present invention. The first liquid crystal structure 116, the first sub-antenna unit 11 further includes:

[0093] The first liquid crystal structure 116 covers the feeding network 115; the first liquid crystal structure 116 is used to adjust the dielectric constant corresponding to the feeding network 115, so that the radiation null point of the first sub-antenna unit 11 is less than the lower limit value of the second operating frequency band. The first liquid crystal structure 116 can be arranged in the printed circuit board 112, such as a through groove for accommodating the first liquid crystal structure 116 is arranged in the printed circuit board 112, and the first liquid crystal structure 116 can also be arranged on the side of the feeding network 115 away from the printed circuit board 112.

[0094] Please refer to Figure 11 which is an antenna gain diagram corresponding to a first sub-antenna unit provided by an embodiment of the present invention. Figure 11 The curves therein are antenna gain curves corresponding to the first liquid crystal structure 116 under different dielectric constants (DK), and the lowest point in the curves represents the radiation null point. From Figure 11 it can be seen that: by changing the dielectric constant, the radiation null point can be changed, and in the first sub-antenna unit 11, as the dielectric constant of the first liquid crystal structure 116 increases, the radiation null point moves towards the low-frequency direction.

[0095] By applying a voltage to the first liquid crystal structure 116, the deflection direction of the liquid crystal molecules in the first liquid crystal structure 116 can be changed, thereby changing the dielectric constant of the first liquid crystal structure 116, so that the radiation null point of the first sub-antenna unit 11 is less than the lower limit value of the second operating frequency band.

[0096] Please refer to Figure 12 which is a top view of an antenna unit provided by an embodiment of the present invention. The orthographic projection shape of the plurality of second sub-antenna units 12 on the floor 13 matches the orthographic projection shape of the radiation plate 111 on the floor 13; for example, if the shape of the radiation plate 111 is square, the orthographic projection shape of the second sub-antenna units 12 on the floor 13 is rectangular, and the shape surrounded by the plurality of second sub-antenna units 12 is approximately square; if the shape of the radiation plate 111 is circular, the orthographic projection shape of the second sub-antenna units 12 on the floor 13 is arc-shaped, and the shape surrounded by the plurality of second sub-antenna units 12 is approximately circular.

[0097] The feeding signals received by two relatively arranged second sub-antenna units 12 have the same amplitude and the same phase, and they form a high-frequency dipole antenna unit.

[0098] By setting the orthographic projection shape of the plurality of second sub-antenna units 12 on the floor 13 to match the orthographic projection shape of the radiation plate 111 on the floor 13, the first sub-antenna unit 11 and the second sub-antenna units 12 can be arranged more compactly, which is convenient for miniaturization of the antenna unit 1.

[0099] Please refer to Figure 13The top view of another antenna unit provided by an embodiment of the present invention. When the total number of multiple second sub-antenna units 12 is four, the amplitudes of the feeding signals received by two adjacent second sub-antenna units 12 are the same and the phases are opposite. They form two high-frequency dipole antenna units, and the two high-frequency dipoles can achieve ±45° polarization.

[0100] By setting the total number of multiple second sub-antenna units 12 to four, the second sub-antenna units 12 can have dual polarization directions. At this time, if the first sub-antenna unit 12 adopts a dual-polarization structure, the antenna unit 1 can achieve dual-band and dual-polarization simultaneously.

[0101] Please refer to Figure 14 and Figure 15 , Figure 14 The three-dimensional schematic diagram of a second sub-antenna unit provided by an embodiment of the present invention. Figure 15 The schematic diagram of the feeding signal line provided by an embodiment of the present invention. The second sub-antenna unit 12 includes:

[0102] A first radiation arm 121 and a second radiation arm 122. The first radiation arm 121 and the second radiation arm 122 are on the same straight line and have no overlap with the first sub-antenna unit 11.

[0103] A balun feeding structure 123. The balun feeding structure 123 includes a grounding structure (not shown) and a feeding signal line 1231. The grounding structure is connected to the first radiation arm 121, and the feeding signal line 1231 is coupled to the second radiation arm 122.

[0104] As Figure 15 shown, the feeding signal line 1231 includes a first branch 12311. The opening direction of the first branch 12311 faces away from the second radiation arm 122. The length L3 of the first branch 12311 is greater than a preset length. The preset length is the length corresponding to the first branch 12311 when the radiation null frequency of the second sub-antenna unit 12 is the upper limit value of the first operating frequency. The feeding signal line 1231 also includes a feeding wire 12312 coupled to the second radiation arm 122. The first branch 12311 is connected to the feeding wire 12312.

[0105] Please refer to Figure 16 The antenna gain diagram of a second sub-unit antenna provided by an embodiment of the present invention. Figure 16 The different curves in Figure 16It can be seen that the length L3 of the second branch 12313 affects the radiation null point of the second sub-antenna unit 12. There is a high-pass filter response with a radiation null point at the edge of the lower frequency band. Therefore, by changing the length L3 of the first branch 12311, high-pass filtering can be achieved, so that the frequency corresponding to the radiation null point of the second sub-antenna unit 12 is greater than the upper limit value of the first operating frequency band, thereby reducing the coupling between the second operating frequency band and the first operating frequency band and improving the isolation between the first sub-antenna unit 11 and the second sub-antenna unit 12.

[0106] Please refer to Figure 17 FIG.

[0107] shows another structural schematic diagram of the feeding signal line provided by an embodiment of the present invention. The feeding signal line 1231 further includes: a feeding wire 12312 connected between the second radiation arm 122 and the feeding signal input terminal; a first branch 12311 located on one side of the feeding wire 12312 and connected to the feeding wire 12312;

[0108] a second branch 12313 and a third branch 12314 located on the other side of the feeding wire 12312 and connected to the feeding wire 12312; the opening directions of the second branch 12313 and the third branch are opposite, and the lengths of the second branch 12313 and the third branch 12314 are 1 / 4 of the wavelength of the electromagnetic wave radiated by the second sub-antenna unit 12.

[0109] By arranging the second branch 12313 and the third branch 12314 connected to the feeding wire 12312 on the same side of the feeding wire 12312 and making them on different sides of the feeding wire 12312 from the first branch 12311, impedance matching can be achieved by using the second branch 12313 and the third branch 12314 without affecting the first branch 12311.

[0110] Please continue to refer to Figure 14 and Figure 18 , Figure 18 FIG.

[0111] shows a sectional view of a second support structure along the extending direction of the first branch. The second sub-antenna unit 12 further includes: a first support structure 124 and a second support structure 125. The first support structure 124 is connected between the first radiation arm 121 and the floor 13 ( Figure 14 not shown), and the second support structure 125 is connected between the second radiation arm 122 and the floor 13 ( Figure 14 not shown); the orthographic projections of the first support structure 124 and the second support structure 125 on the floor 13 are arranged in parallel;

[0112] One side of the first support structure 124 away from the second support structure 125 is entirely covered with copper to form a grounding structure (not shown), and the grounding structure is connected between the first radiation arm 121 and the grounding end; one side of the second support structure 125 away from the first support structure 124 is entirely covered with copper and grounded, and the feeding signal line 1231 is arranged on one side of the second support structure 125 close to the first support structure 124 and is connected to the second radiation arm 122;

[0113] As Figure 18 shown, the second liquid crystal structure 126 covers the first stub 12311; the second liquid crystal structure 126 is used to change the equivalent dielectric constant at the corresponding position of the first stub 12311, so that the radiation null point of the second sub-antenna unit 12 is greater than the upper limit value of the first operating frequency band;

[0114] The second liquid crystal structure 126 is arranged on one side of the second support structure 125 close to the first support structure 124, or is arranged inside the second support structure 125 (for example, a through groove capable of accommodating the second liquid crystal structure 126 is arranged inside the second support structure 125).

[0115] Please refer to Figure 19 for another antenna gain diagram of the second sub-antenna unit provided by the embodiment of the present invention, Figure 19 in which different curves correspond to different dielectric constants (denoted as DK) of the second liquid crystal structure 126. It can be seen from Figure 19 that by changing the dielectric constant of the second liquid crystal structure 126, the position of the radiation null point of the second sub-antenna unit 12 can be changed. As the dielectric constant increases, the radiation null point of the second sub-antenna unit 12 moves towards the high-frequency direction. Therefore, without changing the length of the second stub 12313, the length of the second stub 12313 can also be equivalently changed by adjusting the dielectric constant of the second liquid crystal structure 126, so that the radiation null point of the second sub-antenna unit 12 is greater than the upper limit value of the first operating frequency band.

[0116] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0117] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. An antenna, characterized in that: include: At least one antenna unit, the antenna unit comprising a first sub-antenna unit and a plurality of second sub-antenna units, the plurality of second sub-antenna units being evenly distributed around the first sub-antenna unit, an upper limit value of a first working frequency band of the first sub-antenna unit being less than a lower limit value of a second working frequency band of the second sub-antenna unit, and a height of the first sub-antenna unit being less than a height of the second sub-antenna unit; The frequency corresponding to the radiation zero point of the first sub-antenna unit is less than the lower limit value of the second working frequency band, and the frequency corresponding to the radiation zero point of the second sub-antenna unit is greater than the upper limit value of the first working frequency band.

2. The antenna according to claim 1, characterized in that The antenna unit further includes a floor located at one side of the first sub-antenna unit and not in contact with the first sub-antenna unit, and the first sub-antenna unit includes: a radiation panel located on one side of the floor; The size of the radiation plate is larger than a preset size; wherein the preset size is the size of the radiation plate when the frequency corresponding to the radiation zero point of the first sub-antenna unit is at the lower limit value of the second working frequency band; or, the preset size is the size of the radiation plate in the first sub-antenna unit whose working frequency band is a third working frequency band, the bandwidth of the third working frequency band is the same as the bandwidth of the first working frequency band, and the upper limit value of the third working frequency band is the lower limit value of the second working frequency band.

3. The antenna according to claim 2, characterized in that The first sub-antenna unit also includes: A printed circuit board is located between the radiation board and the floor; a first air layer is provided between the printed circuit board and the radiation board, and a second air layer is provided between the printed circuit board and the floor; a metal layer is provided on a side of the printed circuit board close to the radiation board, and the metal layer has an annular gap extending through the thickness direction; a feeding network is provided on a side of the printed circuit board away from the radiation board; The feeding network comprises a plurality of feeding structures which are not connected to each other, and two feeding structures which are arranged opposite to each other receive feeding signals with the same amplitude but different phases; the plurality of feeding structures are arranged symmetrically on the orthographic projection of the printed circuit board about the center of the annular gap, and the annular gap overlaps the feeding structures; A first liquid crystal structure covers the feeding network; the first liquid crystal structure is used to adjust the dielectric constant corresponding to the feeding network so that the radiation zero point of the first sub-antenna unit is less than the lower limit value of the second working frequency band.

4. The antenna according to any one of claims 2 to 3, characterized in that: The shape of the annular gap is a square; The feeding structure includes a first strip structure, and the first strip structure intersects with one side of the annular gap.

5. The antenna according to claim 4, characterized in that The feeding structure further includes: The second strip structure and the third strip structure are located on both sides of one side of the annular gap and are arranged in parallel, and the first strip structure is connected between the first strip structure and the third strip structure; The second strip-shaped structure is located within the orthographic projection of the annular gap on the printed circuit board, and the third strip-shaped structure is located outside the orthographic projection of the annular gap on the printed circuit board; The length of the second strip-shaped structure is smaller than the length of the third strip-shaped structure, and the length of the third strip-shaped structure is smaller than the side length of the annular gap.

6. The antenna according to any one of claims 2 to 3, characterized in that: The second sub-antenna unit comprises: A first radiation arm and a second radiation arm, wherein the first radiation arm and the second radiation arm are located on the same straight line and have no overlap with the first sub-antenna unit; A balun feeding structure, the balun feeding structure comprising a grounding structure and a feeding signal line, the grounding structure is grounded and connected to the first radiating arm and the second radiating arm, and the feeding signal line is coupled to the second radiating arm; The feed signal line includes a first branch, the opening direction of the first branch is away from the second radiation arm, the length of the first branch is greater than a preset length, and the preset length is the length corresponding to the first branch when the frequency corresponding to the radiation zero point of the second sub-antenna unit is the upper limit value of the first operating frequency.

7. The antenna according to claim 6, characterized in that The second sub-antenna unit also includes: A first supporting structure and a second supporting structure, wherein the first supporting structure is connected between the first radiating arm and the floor, and the second supporting structure is connected between the second radiating arm and the floor; the first supporting structure and the second supporting structure are arranged parallel to the orthographic projection of the floor; The first supporting structure is covered with copper on one side away from the second supporting structure to form a grounding structure connected to the first radiating arm; the second supporting structure is covered with copper on one side away from the first supporting structure to form a grounding structure connected to the second radiating arm, and the feeding signal line is arranged on one side of the second supporting structure close to the first supporting structure and coupled to the second radiating arm; a second liquid crystal structure covering the first branch; the second liquid crystal structure is used to change the equivalent dielectric constant of the corresponding position of the first branch, so that the radiation zero point of the second sub-antenna unit is greater than the upper limit value of the first working frequency band; The second liquid crystal structure is arranged on a side of the second supporting structure close to the first supporting structure, or is arranged inside the second supporting structure.

8. The antenna according to claim 7, characterized in that The feed signal line further includes: A feeder line, one end of which is coupled to the second radiating arm, and the other end of which is connected to a feed signal input end; the first branch is located at one side of the feeder line and is connected to the feeder line; The second branch and the third branch are located on the other side of the feeder and are connected to the feeder; the opening directions of the second branch and the third branch are opposite, and the lengths of the second branch and the third branch are 1 / 4 of the wavelength of the electromagnetic wave radiated by the second sub-antenna unit.

9. The antenna according to claim 6, characterized in that The orthographic projection shapes of the plurality of second sub-antenna units on the floor match the orthographic projection shape of the radiation plate on the floor; The feed signals received by the two second sub-antenna units arranged opposite to each other have the same amplitude and the same phase.

10. The antenna according to claim 9, characterized in that The total number of the plurality of second sub-antenna units is four.

Images