CN113871847A - Low-frequency radiating element and antenna - Google Patents
Low-frequency radiating element and antenna Download PDFInfo
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- CN113871847A CN113871847A CN202010872794.6A CN202010872794A CN113871847A CN 113871847 A CN113871847 A CN 113871847A CN 202010872794 A CN202010872794 A CN 202010872794A CN 113871847 A CN113871847 A CN 113871847A
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- radiation
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
- H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/52—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure
- H01Q1/521—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure reducing the coupling between adjacent antennas
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
- H01Q15/0053—Selective devices used as spatial filter or angular sidelobe filter
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q21/00—Antenna arrays or systems
- H01Q21/30—Combinations of separate antenna units operating in different wavebands and connected to a common feeder system
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Abstract
The invention provides a low-frequency radiation unit and an antenna, which have the technical scheme that the low-frequency radiation unit comprises two pairs of vertically polarized radiation arms, each radiation arm comprises an impedance matching section and a filtering section, each filtering section comprises at least one pair of bending parts which are symmetrical relative to the extension direction of the radiation arm, a wave transmission port is formed between each pair of bending parts, the impedance matching sections and the filtering sections are alternately distributed, two ends of each bending part are respectively and electrically connected with the two impedance matching sections, and the filtering sections are used for enabling phases of local high-frequency coupling currents flowing through the two bending parts to be opposite so as to offset parasitic radiation of the high-frequency coupling currents. By arranging the filter section on the radiation arm, when high-frequency coupling current flows through the two bent parts, the phases of the high-frequency coupling current are opposite, and parasitic radiation is counteracted, so that the interference to the high-frequency radiation unit is reduced, and a high-frequency radiation directional diagram is improved.
Description
Technical Field
The invention relates to the technical field of mobile communication, in particular to a low-frequency radiating unit and an antenna.
Background
The miniaturization design of the multi-band common antenna has become a research hotspot in the mobile communication base station antenna industry. How to design the common caliber of the antennas in different frequency bands in a smaller cross-sectional dimension without sacrificing the performance indexes of each frequency band becomes a difficult problem to be overcome urgently.
At present, the mainstream multi-frequency common antenna needs to support the integration of a plurality of frequency bands of 690-.
Disclosure of Invention
A primary object of the present invention is to provide a low-frequency radiating element that can reduce interference with a high-frequency radiating element.
Another object of the present invention is to provide an antenna using the above low frequency radiating element.
In order to achieve the purpose, the invention provides the following technical scheme:
a low-frequency radiation unit comprises two pairs of vertically polarized radiation arms, wherein each radiation arm comprises an impedance matching section for impedance matching and a filter section for reducing interference on the high-frequency radiation unit, each filter section comprises at least one pair of bending parts symmetrical relative to the extension direction of the radiation arm, a wave transmission port is formed between each pair of bending parts, the impedance matching sections and the filter sections are alternately distributed in the extension direction of the radiation arms, two ends of each bending part are respectively and electrically connected with the two impedance matching sections, and the filter sections are used for enabling phases of local high-frequency coupling currents flowing through the two bending parts to be opposite so as to enable parasitic radiation of the high-frequency coupling currents to be cancelled.
Further setting: the bending part comprises two first conductive segments perpendicular to the extending direction of the radiation arm and a second conductive segment connected between the two first conductive segments, and two ends of the two bending parts are connected with each other to enable the wave-transmitting port to form a closed-port-shaped structure.
Further setting: the length of the first conductive segment is greater than the length of the second conductive segment.
Further setting: each radiation arm is provided with a plurality of bending parts, and the length of the first conductive segment on each bending part is gradually increased along with the position of each bending part which is gradually far away from the center of the low-frequency radiation unit.
Further setting: at least two pairs of bending parts arranged along the extension direction of the radiation arm are arranged between two adjacent impedance matching sections on the same radiation arm.
Further setting: the bending part is arc-shaped or fold-line-shaped and correspondingly enables the wave-transmitting port to be round or diamond-shaped.
Further setting: the radiation arm is a metal strip on the PCB, and the pair of bending parts are arranged on the upper side and the lower side of the PCB and are mutually coupled and connected.
Further setting: the impedance matching section is of a hollow structure.
The invention also provides an antenna, which comprises a first radiation unit array, a second radiation unit array and a third radiation unit array which are in different frequency bands, wherein the first radiation unit array comprises the low-frequency radiation unit, the second radiation unit array comprises a first high-frequency radiation unit, the third radiation unit array comprises a second high-frequency radiation unit, the second radiation unit array and the third radiation unit array are respectively arranged at two sides of the first radiation unit array, and the first high-frequency radiation unit and the second high-frequency radiation unit are arranged at the positions close to the end parts of the radiation arms of the low-frequency radiation unit.
Further setting: the frequency of the first high-frequency radiating unit is higher than that of the second high-frequency radiating unit, and the length of the bent part of the radiating arm of the low-frequency radiating unit close to one side of the first high-frequency radiating unit is smaller than that of the bent part of the radiating arm close to one side of the second high-frequency radiating unit.
Compared with the prior art, the scheme of the invention has the following advantages:
1. in the low-frequency radiation unit, the filter section is arranged on the radiation arm and is formed by the symmetrically arranged bent parts, when high-frequency coupling current flows through the bent parts, because the two bent parts are in a symmetrical structure, the phases of the high-frequency coupling current are opposite, and parasitic radiation is mutually counteracted, thereby reducing the interference on the high-frequency radiation unit, and in addition, the wave transmission port formed between the bent parts also reduces the shielding on the signals of the high-frequency radiation unit, thereby reducing the interference on the high-frequency radiation unit and improving the high-frequency radiation directional diagram.
2. In the antenna related to the invention, by adopting the low-frequency radiation unit, the low-frequency radiation unit reduces the interference to the first high-frequency radiation unit and the second high-frequency radiation unit, the high-frequency radiation directional diagram is improved, and the lengths of the bent parts on different radiation arms on the low-frequency radiation unit are matched with the frequencies of different high-frequency radiation units, so that the better decoupling effect is exerted, and the radiation performance of the antenna is further improved.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
The foregoing and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a schematic structural diagram of a low-frequency radiating element according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a radiation arm according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a radiation arm according to another embodiment of the present invention;
FIG. 4 is a schematic diagram of a radiation arm according to another embodiment of the present invention;
FIG. 5 is a schematic diagram of a radiation arm according to another embodiment of the present invention;
FIG. 6 is a schematic diagram of an antenna according to an embodiment of the present invention;
fig. 7 is a schematic structural diagram of a low-frequency radiating element according to another embodiment of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.
As shown in fig. 1, the present invention provides a low frequency radiation unit 1, which includes two pairs of vertically polarized radiation arms 11 and a feeding balun (not shown) for supporting and feeding the radiation arms 11. The radiation arm 11 comprises an impedance matching section 111 for impedance matching and a filter section 112 for reducing interference to the high-frequency radiation unit, the impedance matching section 111 and the filter section 112 are respectively provided with a plurality of sections, and the impedance matching section 111 and the filter section 112 are alternately distributed in the extension direction of the radiation arm. In this embodiment, the radiating arm 11 is a metal strip on a PCB (not shown).
Specifically, the filter segment 112 includes at least one pair of bent portions 1121 symmetrically distributed with respect to the extending direction of the radiating arm 11, a wave-passing port 1122 is formed between each pair of bent portions 1121, and both ends of each bent portion 1121 are electrically connected to the two impedance matching segments 111, respectively, and the filter segment 112 is configured to make phases of local high-frequency coupling currents flowing through the two bent portions 1121 opposite so as to cancel parasitic radiation of the high-frequency coupling currents.
The filter section 112 is formed by symmetrically arranged pairs of the bent portions 1121, and when the high-frequency coupling current flows through the two bent portions 1121, the directions of the currents are opposite, so that the phases of the high-frequency coupling current on the two bent portions 1121 are opposite, parasitic radiation generated by the high-frequency coupling current is cancelled, and interference on a high-frequency radiation signal is reduced. In addition, a wave-transparent port 1122 is formed between the bent parts 1121, so that interference to high-frequency radiation signals is reduced, a high-frequency radiation pattern is improved, and the radiation performance of the antenna is improved.
In this embodiment, the extending portion 1121 includes two first conductive segments 11211 perpendicular to the extending direction of the radiating arm 11 and a second conductive segment 11212 connected between the two first conductive segments 11211, in this embodiment, the second conductive segment 11212 is parallel to the extending direction of the radiating arm 11, and the two first conductive segments 11211 and the second conductive segment 11212 together form a U-shaped structure. In the present embodiment, the two ends of the two bent portions 1121 are connected to each other to form the wave-transmitting port 1122 into a closed-square structure. In other embodiments, the second conductive segment 11212 may not be parallel to the extending direction of the radiating arm 11, and the two first conductive segments 11211 may also be non-parallel, that is, the bent portion 1121 is not in a U-shaped symmetrical structure, but in a U-shaped asymmetrical structure.
Specifically, since the two bent portions 1121 of the filter segment 112 are symmetrical to each other, and the two first conductive segments 11211 on the bent portions 1121 are also symmetrical to the two first conductive segments 11211 on the other bent portion 1121, when the high-frequency coupling current respectively flows through the first conductive segments 11211 of the two bent portions 1121, the current directions are opposite, and the current phases are opposite, thereby playing a role of reducing interference to the high-frequency radiation signal.
In this embodiment, since the directions of the currents flowing through the second conductive segments 11212 on the two bent portions 1121 are the same, the length of the first conductive segment 11211 is preferably greater than the length of the second conductive segment 11212. In order to further reduce the interference of the low frequency radiating element 1 to the high frequency radiating element, the length of the second conductive segment 11212 may be appropriately reduced, and the length of the first conductive segment 11211 may be extended, and the length of the first conductive segment 11211 may be adjusted according to actual requirements.
In this embodiment, each of the radiating arms 11 is provided with a plurality of bent portions 1121, and the bent portions 1121 have the same structure and the same length. In one embodiment, as shown in fig. 2, lengths of the bent portions 1121 of the radiating arms 11 are different, that is, sizes of the wave-transparent openings 1122 are different, and lengths of the first conductive segments 11211 on the bent portions 1121 are gradually increased as positions of the bent portions 1121 are gradually away from a center of the low-frequency radiating unit 1. Since the high-frequency radiating element is generally disposed at a position close to the end of the radiating arm 11 of the low-frequency radiating element 1, by changing the length of the first conductive segment 11211 of each bent portion 1121, the interference with the high-frequency radiation signal is better reduced, and the influence on the high-frequency radiation characteristic is reduced.
In this embodiment, the junction of the impedance matching section 111 and the filter section 112 is a necking structure. The necking structure can increase the bending length of the bending portion 1121, and thus the length of current flowing through the bending portion is increased. In another embodiment, as shown in fig. 3, the connection between the impedance matching section 111 and the filter section 112 may not be provided with a necking structure, and the bending portion 1121 may be formed by bending and extending the impedance matching section 111 towards the side.
In the present embodiment, each of the filter segments 112 includes a pair of symmetrically disposed bent portions 1121. In other embodiments, the filter segment 112 may further include at least two pairs of bent portions 1121 symmetrically disposed and arranged along the extending direction of the radiation arm 11. In one embodiment, as shown in fig. 4, the filter segment 112 includes two pairs of symmetrically disposed bent portions 1121, that is, at least two pairs of bent portions arranged along the extending direction of the radiating arm 11 are disposed between two adjacent impedance matching segments 111 on the same radiating arm, and a necking structure is formed between two pairs of bent portions 1121 of each filter segment 112. By adopting the structure of connecting a plurality of pairs of bending parts 1121, the requirement of reducing the interference to the high-frequency radiating unit can be met, so that the length of the bending parts 1121 can meet the requirement, the length of the first conductive section 11211 extending outwards can be prevented from being too long, the area of the PCB is reduced, and the production cost is reduced.
Further, in other embodiments, the bending portion 1121 may also have an arc shape or a zigzag shape and correspondingly make the filtering openings have a circular shape or a diamond shape. By changing the shape of the bent portion 1121, the structure of the wave-transmitting port 1122 can be changed, and interference with a high-frequency radiation signal can be reduced.
Further, as shown in fig. 5, the impedance matching section 111 may be a hollow structure. By setting the impedance matching section 111 to be a hollow structure, the shielding of the high-frequency radiation unit is greatly reduced, and the high-frequency radiation directional diagram is improved.
In this embodiment, the filter section 112 and the impedance matching section 111 on the radiation arm 11 are in a direct connection structure, and in other embodiments, the filter section 112 and the impedance matching section 111 may also be in an interdigital coupling structure or an upper and lower coupling structure, so as to achieve electrical connection.
In this embodiment, the two extending portions 1121 of the filter segment 112 are directly electrically connected, in other embodiments, the two extending portions 1121 may be disposed on the upper and lower sides of the PCB and coupled to each other, or may be formed by an interdigital coupling structure to form a non-closed structure.
In this embodiment, the radiating arms 11 are cross dipole structures, and in other embodiments, the radiating arms 11 may also be rectangular dipole structures, folded dipole structures, or plus-minus 45-degree cross dipole structures.
The invention further provides an antenna, which is shown in fig. 6 and includes a first radiation unit array, a second radiation unit array and a third radiation unit array of different frequency bands, wherein the first radiation unit array includes the low-frequency radiation unit 1, the second radiation unit array includes a first high-frequency radiation unit 2, the third radiation unit array includes a second high-frequency radiation unit 3, the second radiation unit array and the third radiation unit array are respectively disposed on two sides of the first radiation unit array, and the first high-frequency radiation unit 2 and the second high-frequency radiation unit 3 are disposed at positions close to the end portion of the radiation arm 11 of the low-frequency radiation unit 1.
As shown in fig. 7, further, the frequency of the first high-frequency radiating element 2 is higher than that of the second high-frequency radiating element 3, and the length of the bent portion 1121 of the radiating arm 11 of the low-frequency radiating element 1 on the side close to the first high-frequency radiating element 2 is smaller than that of the bent portion 1121 of the radiating arm 11 on the side close to the second high-frequency radiating element 3.
Through adjusting the size of filter section 112 on the radiation arm 11 to low frequency radiation unit 1, satisfy the demand that reduces the interference to the high frequency radiation unit of different frequency channels better, promote the radiation performance of antenna.
In summary, the scheme of the invention has the following advantages:
1. in the low-frequency radiation unit 1 according to the present invention, the filter section 112 is disposed on the radiation arm 11, and the filter section 112 is formed by the symmetrically disposed bent portions 1121, so that when a high-frequency coupling current flows through the bent portions 1121, since the two bent portions 1121 have a symmetrical structure, phases of the high-frequency coupling current are opposite, parasitic radiation cancels each other, thereby reducing interference to the high-frequency radiation unit and improving a high-frequency radiation pattern.
2. In the antenna related to the present invention, by using the low-frequency radiating element 1, the low-frequency radiating element 1 reduces interference to the first high-frequency radiating element 2 and the second high-frequency radiating element 3, and improves a high-frequency radiation pattern, and lengths of the bent portions 1121 on different radiating arms 11 on the low-frequency radiating element 1 are matched with frequencies of different high-frequency radiating elements, so as to exert a better decoupling effect, and further improve radiation performance of the antenna.
The foregoing is only a partial embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. A low-frequency radiation unit is characterized in that: the radiation arm comprises two pairs of vertically polarized radiation arms, the radiation arms comprise impedance matching sections used for impedance matching and filter sections used for reducing interference to high-frequency radiation units, each filter section comprises at least one pair of bending parts symmetrical relative to the extension direction of the radiation arm, a wave transmission port is formed between each pair of bending parts, the impedance matching sections and the filter sections are alternately distributed in the extension direction of the radiation arms, two ends of each bending part are respectively electrically connected with the two impedance matching sections, and the filter sections are used for enabling phases of local high-frequency coupling currents flowing through the two bending parts to be opposite so as to enable parasitic radiation of the high-frequency coupling currents to be cancelled.
2. The low frequency radiating element of claim 1, wherein: the bending part comprises two first conductive segments perpendicular to the extending direction of the radiation arm and a second conductive segment connected between the two first conductive segments, and two ends of the two bending parts are connected with each other to enable the wave-transmitting port to form a closed-port-shaped structure.
3. The low frequency radiating element of claim 2, wherein: the length of the first conductive segment is greater than the length of the second conductive segment.
4. The low frequency radiating element of claim 2, wherein: each radiation arm is provided with a plurality of bending parts, and the length of the first conductive segment on each bending part is gradually increased along with the position of each bending part which is gradually far away from the center of the low-frequency radiation unit.
5. The low frequency radiating element of claim 1, wherein: at least two pairs of bending parts arranged along the extension direction of the radiation arm are arranged between two adjacent impedance matching sections on the same radiation arm.
6. The low frequency radiating element of claim 1, wherein: the bending part is arc-shaped or fold-line-shaped and correspondingly enables the wave-transmitting port to be round or diamond-shaped.
7. The low frequency radiating element of claim 1, wherein: the radiation arm is a metal strip on the PCB, the pair of bending parts are arranged on the upper side and the lower side of the PCB, and the end parts of the bending parts are mutually coupled and connected.
8. The low frequency radiating element of claim 1, wherein: the impedance matching section is of a hollow structure.
9. An antenna comprises a first radiating element array, a second radiating element array and a third radiating element array in different frequency bands, and is characterized in that: the first radiation element array comprises the low-frequency radiation element according to any one of claims 1 to 8, the second radiation element array comprises a first high-frequency radiation element, the third radiation element array comprises a second high-frequency radiation element, the second radiation element array and the third radiation element array are respectively arranged at two sides of the first radiation element array, and the first high-frequency radiation element and the second high-frequency radiation element are arranged at positions close to the end parts of the radiation arms of the low-frequency radiation element.
10. The antenna of claim 9, wherein: the frequency of the first high-frequency radiating unit is higher than that of the second high-frequency radiating unit, and the length of the bent part of the radiating arm of the low-frequency radiating unit close to one side of the first high-frequency radiating unit is smaller than that of the bent part of the radiating arm close to one side of the second high-frequency radiating unit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2020106229594 | 2020-06-30 | ||
| CN202010622959.4A CN111613883A (en) | 2020-06-30 | 2020-06-30 | Low-frequency radiating element and antenna |
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| Publication Number | Publication Date |
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| CN113871847A true CN113871847A (en) | 2021-12-31 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010622959.4A Pending CN111613883A (en) | 2020-06-30 | 2020-06-30 | Low-frequency radiating element and antenna |
| CN202010872794.6A Pending CN113871847A (en) | 2020-06-30 | 2020-08-26 | Low-frequency radiating element and antenna |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010622959.4A Pending CN111613883A (en) | 2020-06-30 | 2020-06-30 | Low-frequency radiating element and antenna |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112201958B (en) * | 2020-09-18 | 2023-08-15 | Oppo广东移动通信有限公司 | Multi-frequency antenna, antenna assembly and customer premises equipment |
| CN112768895B (en) * | 2020-12-29 | 2022-05-03 | 华南理工大学 | Antenna, low-frequency oscillator and radiating element |
| CN113314833B (en) * | 2021-04-16 | 2022-08-05 | 华南理工大学 | Low-scattering radiation unit and multi-frequency common-aperture antenna array |
| CN115566423A (en) * | 2021-07-02 | 2023-01-03 | 华为技术有限公司 | Antenna structure, base station antenna and base station |
| CN114927859A (en) * | 2022-06-20 | 2022-08-19 | 广州司南技术有限公司 | Wideband radiating element for multi-band base station antenna |
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2020
- 2020-06-30 CN CN202010622959.4A patent/CN111613883A/en active Pending
- 2020-08-26 CN CN202010872794.6A patent/CN113871847A/en active Pending
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