Low-profile antenna and electronic equipment
By designing a polarized orthogonal radiating antenna and adding a parasitic loop structure, the impedance mismatch problem of traditional antennas at low profiles was solved, thus achieving stability and reliability of signal transmission.
Patent Information
- Application Number
- CN202520599927.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-03-31
AI Technical Summary
Traditional dipole antennas cannot function properly in low profile conditions, resulting in impedance mismatch.
By designing a first and second radiating antenna with mutually orthogonal polarization directions, and adding a first and second parasitic ring on their basis, adjusting their length and width to adjust the input impedance, and canceling the capacitive component brought by the ground plane, polarization isolation and impedance matching are achieved.
Under extremely low profile conditions, the stability and reliability of signal transmission are improved, enabling the antenna to operate normally.
Smart Images
Figure CN223956826U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of communication antennas, and particularly relates to a low-profile antenna and an electronic device. BACKGROUND
[0002] At present, generally speaking, a traditional dipole antenna needs to be 0.25 lambda away from the ground to ensure normal radiation, but in most ceiling-mounted access points (APs), the profile height reserved for the antenna is only 9 mm (0.07 lambda), which will cause serious impedance mismatch of the antenna and the antenna cannot work normally. CONTENT
[0003] The application aims to provide a low-profile antenna and an electronic device, and aims to solve the problem that a traditional antenna cannot work normally in a low-profile case.
[0004] A first aspect of the application provides a low-profile antenna, comprising a circuit board; a first surface of the circuit board is provided with a first radiation antenna, the first radiation antenna comprises symmetrically arranged first and second antenna arms, and the first and second antenna arms are connected through a first parasitic ring; a second surface of the circuit board is provided with a second radiation antenna, and a polarization direction of the second radiation antenna is orthogonal to a polarization direction of the first radiation antenna.
[0005] In one embodiment, the second radiation antenna comprises symmetrically arranged third and fourth antenna arms, and the third and fourth antenna arms are connected through a second parasitic ring.
[0006] In one embodiment, a symmetric center of the first radiation antenna coincides with a symmetric center of the second radiation antenna in a projection of the second surface of the circuit board.
[0007] In one embodiment, a projection of the first parasitic ring on the second surface of the circuit board coincides with the second parasitic ring.
[0008] In one embodiment, the first antenna arm extends in a first direction away from the second antenna arm, the first antenna arm comprises a first radiator and a second radiator arranged in sequence in the first direction, and a width of the first radiator is smaller than a width of the second radiator.
[0009] In one embodiment, the second radiator is provided with a U-shaped slot, and an opening of the U-shaped slot faces the first radiator.
[0010] In one embodiment, the third antenna arm extends in a second direction away from the fourth antenna arm, the third antenna arm comprises a third radiator and a fourth radiator arranged in sequence in the second direction, and the third radiator has a width smaller than that of the fourth radiator.
[0011] In one embodiment, an end of the first antenna arm close to the second antenna arm, an end of the second antenna arm close to the first antenna arm, an end of the third antenna arm close to the fourth antenna arm, and an end of the fourth antenna arm close to the third antenna arm are respectively provided with a soldering point for connecting with a corresponding radio frequency line.
[0012] A second aspect of the embodiment of the present application provides an electronic device, comprising a metal ground and the low-profile antenna as described above.
[0013] In one embodiment, a tuning circuit is further included, which is connected between the low-profile antenna and a signal source, and is configured to configure an antenna standing wave.
[0014] Compared with the prior art, the embodiment of the present application has the beneficial effect that the polarization isolation of the first radiation antenna and the second radiation antenna can be achieved by the orthogonal polarization directions of the first radiation antenna and the second radiation antenna, so as to improve the stability and reliability of signal transmission of the low-profile antenna.
[0015] The first parasitic ring is added to the first radiation antenna, so that the current changes from one path to two paths, and the input impedance of the first radiation antenna port can be adjusted by adjusting the length and width of the first parasitic ring, the inductive component in the input impedance of the first radiation antenna is improved, and thus the strong capacitive component caused by the floor can be offset in the case of low profile, so that the first radiation antenna can still work normally under the condition of extremely low profile. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 A schematic diagram of the low-profile antenna according to one embodiment of the present application;
[0017] Figure 2 A schematic diagram of the first radiation antenna according to one embodiment of the present application;
[0018] Figure 3 A schematic diagram of the second radiation antenna according to one embodiment of the present application;
[0019] Figure 4 A radiation pattern of the low-profile antenna according to one embodiment of the present application;
[0020] Figure 5 Another radiation pattern of the low-profile antenna according to one embodiment of the present application;
[0021] Figure 6 Another radiation pattern of the low profile antenna provided by an embodiment of the present application;
[0022] Figure 7 A structural schematic diagram of an electronic device provided by an embodiment of the present application;
[0023] Figure 8 A circuit schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION
[0024] In order to make the technical problems to be solved, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.
[0025] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.
[0026] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0027] In addition, the terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.
[0028] Figure 1 A schematic diagram of a low profile antenna provided by an embodiment of the present application is shown, only the parts related to the present embodiment are shown for the convenience of description, and the details are as follows:
[0029] As shown in Figure 1 , Figure 2 , Figure 3 , a low profile antenna includes a circuit board 100.
[0030] A first radiating antenna 200 is provided on the first surface of the circuit board 100. The first radiating antenna 200 includes a first antenna arm 210 and a second antenna arm 220 arranged symmetrically. The first antenna arm 210 and the second antenna arm 220 are connected by a first parasitic ring 410. A second radiating antenna 300 is provided on the second surface of the circuit board 100. The polarization direction of the second radiating antenna 300 is orthogonal to the polarization direction of the first radiating antenna 200.
[0031] By making the polarization directions of the first radiating antenna 200 and the second radiating antenna 300 orthogonal to each other, the polarization of the first radiating antenna 200 and the second radiating antenna 300 can be isolated, thereby improving the stability and reliability of signal transmission of the low-profile antenna.
[0032] A first parasitic ring 410 is added to the first radiating antenna 200, which changes the current from one path to two paths. The input impedance of the port of the first radiating antenna 200 can be adjusted by adjusting the length and width of the first parasitic ring 410, thereby increasing the inductive component in the input impedance of the first radiating antenna 200. This can offset the strong capacitive component brought by the ground plane under low profile conditions, so that the first radiating antenna 200 can still work normally under extremely low profile conditions.
[0033] Specifically, the first radiating antenna 200 and the second radiating antenna 300 can be metal patches constructed on the surface of the circuit board 100.
[0034] The specific dimensions and patterns of the first radiating antenna 200 and the second radiating antenna 300 can be configured according to parameters such as the frequency of the transmitted signal.
[0035] In some embodiments, the first radiating antenna 200 and the second radiating antenna 300 have the same size and pattern.
[0036] In some embodiments, the first radiating antenna 200 and the second radiating antenna 300 may operate in at least one of the following frequency bands: 2.4 GHz, 5 GHz, and Bluetooth.
[0037] In one embodiment, such as Figure 3 As shown, the second radiating antenna 300 includes a third antenna arm 310 and a fourth antenna arm 320 arranged symmetrically, and the third antenna arm 310 and the fourth antenna arm 320 are connected by a second parasitic ring 420.
[0038] Understandably, the input impedance of the port of the second radiating antenna 300 can be adjusted by adjusting the length and width of the second parasitic ring 420, thereby increasing the inductive component in the input impedance of the second radiating antenna 300. This can offset the strong capacitive component brought by the ground plane under low profile conditions, allowing the second radiating antenna 300 to still work normally under extremely low profile conditions.
[0039] In some embodiments, the first parasitic ring 410 and the second parasitic ring 420 are rectangular.
[0040] In one embodiment, the orthographic projection of the center of symmetry of the first radiating antenna 200 onto the second surface of the circuit board 100 coincides with the center of symmetry of the second radiating antenna 300.
[0041] It can improve the symmetry of low-profile antennas to achieve polarization diversity and improve the polarization isolation between the first radiating antenna 200 and the second radiating antenna 300.
[0042] When the first radiating antenna 200 and the second radiating antenna 300 have the same size and pattern, one of the radiating antennas can be rotated 90° around the center of symmetry so that the orthographic projections of the two radiating antennas on the same plane coincide.
[0043] In one embodiment, the orthographic projection of the first parasitic ring 410 onto the second surface of the circuit board 100 coincides with the second parasitic ring 420.
[0044] It should be noted that since the first parasitic ring 410 is connected to the first radiating antenna 200 and the second parasitic ring 420 is connected to the second radiating antenna 300, the first parasitic ring 410 and the second parasitic ring 420 will inevitably generate radiation, which will make the antenna impedance matching and debugging more difficult.
[0045] By aligning the orthographic projection of the first parasitic ring 410 onto the second surface of the circuit board 100 with the second parasitic ring 420, a waveguide structure for transmitting energy can be formed. Taking the first parasitic ring 410 as an example, when current flows through the first parasitic ring 410, an induced current in the opposite direction will be generated on the second parasitic ring 420, thereby confining the energy and preventing it from radiating outward.
[0046] Furthermore, by aligning the orthographic projection of the first parasitic ring 410 onto the second surface of the circuit board 100 with the second parasitic ring 420, the symmetry of the low-profile antenna can be increased, and the polarization isolation between the first radiating antenna 200 and the second radiating antenna 300 can be improved.
[0047] In one embodiment, such as Figure 2 As shown, the first antenna arm 210 extends along a first direction away from the second antenna arm 220. The first antenna arm 210 includes a first radiator 211 and a second radiator 212 arranged sequentially along the first direction. The width of the first radiator 211 is smaller than the width of the second radiator 212.
[0048] It can be understood that, in the case of symmetrical arrangement of the first antenna arm 210 and the second antenna arm 220, after the pattern and shape of the first antenna arm 210 are determined, the pattern and shape of the second antenna arm 220 can be obtained according to the first antenna arm 210.
[0049] Specifically, the first antenna arm 210 is in a stepped shape, and the widening of the width of the end of the first antenna arm 210 can introduce parasitic capacitance and inductance effects, which is conducive to achieving impedance matching of the antenna.
[0050] By adjusting the length and width of the first parasitic loop 410 to change the input impedance of the first radiating antenna 200, and further adjusting the stepped width of the first antenna arm 210 and the second antenna arm 220 to complete impedance matching, the first radiating antenna 200 can work at an extremely low profile.
[0051] In an embodiment, the second radiating body 212 is provided with a U-shaped gap 230, and the opening of the U-shaped gap 230 faces the first radiating body 211.
[0052] By providing the U-shaped gap 230 on the second radiating body 212, a corresponding radiation signal can be generated when the current flows through the U-shaped gap 230, so that the first radiating antenna 200 works at two frequency bands, one of which corresponds to the length and width of the first radiating antenna 200, and the other of which corresponds to the length of the U-shaped gap 230.
[0053] It should be noted that a double-frequency self-decoupling design cannot be realized on a printed circuit board (PCB) using traditional low-profile technology, while the embodiments of the present application can improve the stability and reliability of signal transmission of the low-profile antenna by using polarization diversity technology in cooperation with the first parasitic loop 410 and the second parasitic loop 420, and can realize double-frequency self-decoupling by cooperating with the U-shaped gap 230.
[0054] In some embodiments, the length of the U-shaped gap 230 is half of the wavelength corresponding to the 5.2 GHz frequency band, and when the current flows through the U-shaped gap 230, the U-shaped gap 230 will excite a radiation signal at the 5.2 GHz frequency band, thereby realizing double-frequency operation of the first radiating antenna 200.
[0055] In an embodiment, as shown in Figure 3 The third antenna arm 310 extends in a second direction away from the fourth antenna arm 320, and the third antenna arm 310 includes a third radiating body 311 and a fourth radiating body 312 arranged in sequence along the second direction, and the width of the third radiating body 311 is smaller than the width of the fourth radiating body 312.
[0056] The second direction can be perpendicular to the first direction.
[0057] It can be understood that, in the case of the third antenna arm 310 and the fourth antenna arm 320 being symmetrically arranged, after the pattern and shape of the third antenna arm 310 are determined, the pattern and shape of the fourth antenna arm 320 can be obtained according to the third antenna arm 310.
[0058] Specifically, the third antenna arm 310 is in a stepped shape, and the third antenna arm 310 end width widening can introduce parasitic capacitance and inductance effects, which is conducive to realizing impedance matching of the antenna.
[0059] By adjusting the length and width of the second parasitic loop 420 to change the input impedance of the second radiating antenna 300, and then adjusting the stepped width of the third antenna arm 310 and the fourth antenna arm 320 to further complete impedance matching, the second radiating antenna 300 can work at an extremely low profile.
[0060] In an embodiment, one end of the first antenna arm 210 close to the second antenna arm 220, one end of the second antenna arm 220 close to the first antenna arm 210, one end of the third antenna arm 310 close to the fourth antenna arm 320, and one end of the fourth antenna arm 320 close to the third antenna arm 310 are each provided with a soldering point 500, which is used for connecting with a corresponding radio frequency cable (RF Cable).
[0061] The soldering point 500 of the first antenna arm 210 can be arranged in a staggered manner with the soldering point 500 of the second antenna arm 220.
[0062] The soldering point 500 can avoid the radio frequency cable from passing through the radiator of the radiating antenna.
[0063] Exemplarily, Figure 4 is the radiation pattern of the first radiating antenna 200 at a 2.4 GHz frequency band, and the maximum gain is 8.5 dBi, Figure 5 is the radiation pattern of the first radiating antenna 200 at a 5.2 GHz frequency band, and the maximum gain is 9 dBi, Figure 6 is the radiation pattern of the second radiating antenna 300 at a 2.4 GHz frequency band, and the maximum gain is 8.5 dBi.
[0064] Figure 7 A structure schematic diagram of an electronic device provided by an embodiment of the present application is shown, only parts related to the present embodiment are shown for the convenience of description, and the details are as follows:
[0065] An electronic device 20 includes a metal ground 30 and a low-profile antenna 10 according to any one of the above embodiments, and the metal ground 30 is arranged in a spaced manner with the low-profile antenna 10.
[0066] Specifically, the low-profile antenna 10 can be arranged in a spaced manner with the metal ground 30. The spacing between the low-profile antenna 10 and the metal ground 30 can be less than 10 mm.
[0067] As shown in Figure 1 , Figure 2 , Figure 3 The low profile antenna comprises a circuit board 100.
[0068] The first surface of the circuit board 100 is provided with a first radiating antenna 200, the first radiating antenna 200 comprising a first antenna arm 210 and a second antenna arm 220 symmetrically arranged, the first antenna arm 210 and the second antenna arm 220 being connected through a first parasitic loop 410; the second surface of the circuit board 100 is provided with a second radiating antenna 300, the polarization direction of the second radiating antenna 300 being orthogonal to the polarization direction of the first radiating antenna 200.
[0069] By making the polarization directions of the first radiating antenna 200 and the second radiating antenna 300 orthogonal to each other, the polarization isolation of the first radiating antenna 200 and the second radiating antenna 300 can be achieved, so as to improve the stability and reliability of signal transmission of the low profile antenna.
[0070] The first parasitic loop 410 is added on the basis of the first radiating antenna 200, so that the current changes from one path to two paths, and thus the input impedance of the first radiating antenna 200 port can be adjusted by adjusting the length and width of the first parasitic loop 410, the inductive component in the input impedance of the first radiating antenna 200 is improved, so that the strong capacitive component brought by the floor can be offset in the case of low profile, and the first radiating antenna 200 can still work normally under the condition of extremely low profile.
[0071] In some embodiments, the spacing between the circuit board 100 and the metal ground 30 is 9mm.
[0072] As shown in Figure 8 In an embodiment, the electronic device 20 further comprises a tuning circuit 40 connected between the low profile antenna 10 and a signal source, the tuning circuit 40 being configured to configure the antenna standing wave.
[0073] The tuning circuit 40 comprises a capacitor, an inductor, a resistor, etc.
[0074] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent ones; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.
Claims
1. A low profile antenna, characterized by, The circuit board comprises a first surface and a second surface opposite to the first surface. The first surface of the circuit board is provided with a first radiating antenna, the first radiating antenna comprises a first antenna arm and a second antenna arm arranged symmetrically, and the first antenna arm and the second antenna arm are connected by a first parasitic loop. The second surface of the circuit board is provided with a second radiating antenna, and a polarization direction of the second radiating antenna is orthogonal to a polarization direction of the first radiating antenna.
2. The low profile antenna of claim 1, wherein, The second radiating antenna comprises a third antenna arm and a fourth antenna arm arranged symmetrically, and the third antenna arm and the fourth antenna arm are connected by a second parasitic loop.
3. The low profile antenna of claim 2, wherein, A symmetric center of the first radiating antenna coincides with a symmetric center of the second radiating antenna in a projection of the second surface of the circuit board.
4. The low profile antenna of claim 2, wherein, A projection of the first parasitic loop on the second surface of the circuit board coincides with the second parasitic loop.
5. A low profile antenna as claimed in any one of claims 1 to 4, wherein, The first antenna arm extends in a first direction away from the second antenna arm, and the first antenna arm comprises a first radiator and a second radiator arranged in sequence in the first direction, and a width of the first radiator is smaller than a width of the second radiator.
6. The low profile antenna of claim 5, wherein, The second radiator is provided with a U-shaped slot, and an opening of the U-shaped slot faces the first radiator.
7. A low profile antenna as claimed in any one of claims 2 to 4, wherein The third antenna arm extends in a second direction away from the fourth antenna arm, and the third antenna arm comprises a third radiator and a fourth radiator arranged in sequence in the second direction, and a width of the third radiator is smaller than a width of the fourth radiator.
8. A low profile antenna as claimed in any one of claims 2 to 4, wherein, An end of the first antenna arm close to the second antenna arm, an end of the second antenna arm close to the first antenna arm, an end of the third antenna arm close to the fourth antenna arm, and an end of the fourth antenna arm close to the third antenna arm are all provided with a welding point, and the welding point is used for being connected with a corresponding radio frequency wire.
9. An electronic device, comprising: The low profile antenna comprises a metal ground, and the metal ground is arranged apart from the low profile antenna.
10. The electronic device of claim 9, wherein, A tuning circuit is further included, and the tuning circuit is connected between the low profile antenna and a signal source, and the tuning circuit is used for configuring an antenna standing wave.