Novel dual-frequency filtering antenna

Abstract

Disclosed in the present invention is a novel dual-frequency filtering antenna, comprising a base, a group of baluns arranged in a crossed manner on the base, and a first radiation arm and a second radiation arm which are connected to the group of baluns. The front surfaces and the back surfaces of the first radiation arm and the second radiation arm are all printed with copper foils. Each copper foil is divided into a plurality of small modules, and connecting modules are further provided between the small modules. The front surface of each small module is provided with a C-shaped gap, and the edge of each small module is provided with an inverted-L-shaped branch. The present invention ensures that radiation interference and shielding with respect to other civil communication frequency bands can be reduced without affecting own radiation function, thus having very high universality and practicability in the aspect of multi-frequency-band and multi-system antenna fusion. The present invention creatively integrates multiple filtering decoupling technologies into one antenna, achieving double-frequency-band decoupling, and also extending the filtering bandwidth.

Description

A new type of dual-band filtering antenna Technical field:

[0001] The present invention belongs to the technical field of filtering antennas, and in particular relates to a novel dual-frequency filtering antenna. Background technology:

[0002] Antennas, as a key component in communication systems, are used to convert guided waves into free-space electromagnetic waves. Civilian mobile communication systems rely on base station antennas to enable information transmission and interaction between base station equipment and mobile terminals. Currently, fifth-generation mobile communications (5G) have been commercialized. The development of mobile communication technology is a process of continuous enrichment and evolution. The commercialization of 5G will not cause the immediate decommissioning of 2G / 3G / 4G communication systems. Therefore, 2G / 3G / 4G / 5G communication systems will inevitably coexist and be jointly developed for a long time.

[0003] 5G antennas require extensive coverage. Using independent deployment methods would exacerbate the shortage of base station sites, resulting in significant waste and a significant increase in operating costs. To save costs, 5G base station antennas are being integrated with existing 2G / 3G / 4G base station antennas to achieve multi-band, multi-standard base station antenna convergence. This allows for signal coverage of multiple network standards without increasing the footprint of base station antenna equipment. This significantly alleviates the shortage of base station site resources and reduces operating costs for operators. This significantly promotes the commercialization of 5G and accelerates the country's information modernization efforts.

[0004] According to this planning concept, 2G / 3G / 4G / 5G will share a single reflector and radome, creating what is known as a multi-band co-aperture base station antenna. To suppress the coupling interference between sub-antenna systems operating in different frequency bands within the same antenna, filter antenna technology has been widely adopted in the base station antenna field. Currently, the primary challenge facing multi-band converged base station antennas is suppressing cross-band coupling. Therefore, inter-frequency decoupling technology for multi-frequency array antennas has become a research hotspot in the base station antenna field. This invention addresses the urgent needs of the antenna industry by designing a dual-band filter antenna suitable for multi-band converged scenarios.

[0005] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0006] Summary of the invention:

[0007] The purpose of the present invention is to provide a novel dual-frequency filtering antenna, thereby overcoming the above-mentioned defects in the prior art.

[0008] In order to achieve the above-mentioned objectives, the present invention provides a novel dual-band filtering antenna, comprising a base, a group of baluns cross-arranged on the base, and a first radiating arm and a second radiating arm connected to the group of baluns, wherein the front and back sides of the first radiating arm and the second radiating arm are printed with copper foil, and the copper foil is divided into a plurality of small modules, and a connecting module is further provided between each small module, and a C-shaped gap is opened on the front side of each small module, and an inverted L-shaped branch is provided at the edge.

[0009] Furthermore, preferably, the dielectric constant of the first radiation arm and the second radiation arm ranges from 2.0 to 10.0, and the thickness ranges from 0.2 to 3 mm.

[0010] Furthermore, preferably, the copper foil is provided with a plurality of metallized vias, which connect the copper foils on the front and back sides. This form is equivalent to thickening the thickness of the metal on the radiating arm, which plays a role in delaying the impedance change of the radiating arm and is beneficial to its own impedance matching.

[0011] Furthermore, preferably, the connection module is a V-shaped module for electrically connecting to two adjacent small modules.

[0012] Furthermore, preferably, a feeding microstrip line is provided on the front side of the balun, and a metal ground is provided on the back side.

[0013] Furthermore, preferably, a via is provided at the end of the feeding microstrip line, and the via transmits energy to the metal ground of the balun through the metal ground.

[0014] Furthermore, as a preference, two copper foils are provided near the center of the front of the first radiation arm and the second radiation arm, and the top of the balun metal ground is connected to the two copper foils, and the two are connected by welding. The two copper foils couple the energy fed into the balun to the copper foil on the back of the radiation arm for transmission, and finally complete the radiation.

[0015] Furthermore, as a preference, the metal ground also adopts copper foil.

[0016] Furthermore, preferably, there are two baluns, namely a first balun and a second balun, and the first balun and the second balun are orthogonally arranged on the base.

[0017] Furthermore, preferably, the antenna is used to filter out radiation waves in the 1710MHz-2690MHz frequency band and the 3300MHz-3800MHz frequency band.

[0018] Compared with the prior art, one aspect of the present invention has the following beneficial effects:

[0019] (1) The present invention can reduce its own radiation interference and shielding to other civilian communication frequency bands without affecting its own radiation function, and has very high versatility and practicality in the integration of multi-band and multi-standard antennas;

[0020] (2) The present invention innovatively integrates multiple filtering and decoupling technologies into one antenna, achieving dual-band decoupling while extending the filtering bandwidth. Description of the drawings:

[0021] FIG1 is an overall schematic diagram of a novel dual-frequency filtering antenna of the present invention;

[0022] FIG2 is a front view of a radiating arm of a novel dual-frequency filtering antenna of the present invention;

[0023] FIG3 is a schematic diagram of the back side of a radiating arm of a novel dual-frequency filtering antenna of the present invention;

[0024] FIG4 is a front view of a first balun of a novel dual-frequency filtering antenna of the present invention;

[0025] FIG5 is a schematic diagram of the back side of a first balun of a novel dual-band filtering antenna of the present invention;

[0026] FIG6 is a front view of a second balun of a novel dual-frequency filtering antenna according to the present invention;

[0027] FIG7 is a schematic diagram of the back side of the second balun of a novel dual-band filtering antenna of the present invention;

[0028] FIG8 is a front view of a balun base of a novel dual-band filtering antenna according to the present invention;

[0029] FIG9 is a schematic diagram of the back side of a balun base of a novel dual-band filtering antenna according to the present invention;

[0030] Figure markings: 1-balun base, 2-first balun, 21-first slot, 3-second balun, 31-second slot, 4-first radiation arm, 5-second radiation arm, 6-rectangular feeding plate, 61-press jack, 7-protruding branch, 8-copper foil, 81-metallized via, 82-small module, 83-"only" shaped choke, 84-C-shaped gap, 85-inverted L-shaped branch, 9-protruding branch, 10-feeding microstrip line, 11 / 15-metal ground, 12-short-circuit metallized via, 13-mounting slot, 14-circular mounting hole. Specific implementation method:

[0031] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0032] A brief overview of one or more aspects is given below to provide a basic understanding of these aspects. This overview is not an exhaustive survey of all contemplated aspects and is neither intended to identify key or decisive elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that follows.

[0033] Embodiment 1:

[0034] As shown in FIG. 1, a novel dual - band filtering antenna comprises a balun base 1 for fixed support, a first balun 2 for feeding and a second balun 3 which are cross - assembled on the balun base 1, and a first radiation arm 4 and a second radiation arm 5 which are cross - stacked on the first balun 2 and the second balun 3. The two radiation arm structures are exactly the same and are respectively responsible for the radiation of two polarizations of the antenna.

[0035] Specifically, as shown in FIGS. 2 and 3, two rectangular feeding pieces 6 for connecting to the top of the balun are printed on the front of each radiation arm. A press - fit hole 61 is provided at the rectangular feeding piece. Protruding branches 7 are provided at the tops of the first balun 2 and the second balun 3. The protruding branches 7 are fitted and installed with the press - fit hole 61. Physically, the rectangular feeding piece 6 plays a role in fixing the radiation arm and the balun.

[0036] Copper foils 8 are printed on both the front and the back of each radiation arm. A number of metallized vias 81 are densely provided on the copper foils 8. The metallized vias 81 connect the front copper foil and the back copper foil. The copper foil 8 is divided into several small modules 82. Each small module is connected by a "zigzag" choke 83 (i.e., a connecting module). After the copper foil 8 is interrupted, its electrical length is far from the resonant wavelength of the filtering frequency band. Therefore, the induced current on the radiation arm is small and cannot form secondary radiation, thus reducing the interference of the radiation arm itself to the filtering frequency band. And when the copper foil 8 is interrupted, its own current path is also interrupted. Therefore, it cannot normally work in the 690 - 960 frequency band. At this time, the "zigzag" choke 83 forms a connection between the small modules, which can ensure that the entire radiation arm can allow the normal working current of itself to pass through and play an electrical connection role. The electrical connection mainly relies on coupling because the choke is very close to the interrupted small module, and the gap is only about 0.4 mm. It is responsible for coupling energy from one small module to another.

[0037] The "zhi"-shaped choke has two slender arms, namely the two legs of the "zhi"-shaped structure. When the radiation waves in the frequency band of 1710 MHz - 2690 MHz irradiate on it, the currents in the two legs of the "zhi"-shaped structure can cancel each other out in the reverse direction, so that the induced currents on it also cancel each other out in the reverse direction, which can greatly weaken the secondary radiation and further reduce the interference of the choke itself on the filtering frequency band. And the length of the choke leg determines the filtering frequency band. The longer the leg, the longer the electrical length, and the corresponding filtering frequency band shifts more towards the lower frequency band. The length is generally less than one-eighth of the wavelength of the filtering frequency point. This way of interruption and then connection through the choke mainly filters the radiation waves in the frequency band of 1710 MHz - 2690 MHz. The choke not only plays the role of electrical connection in its own frequency band, making the working current on the radiation arm continuous, but also can filter the induced currents in other frequency bands, and its electrical length affects the filtering frequency band.

[0038] A C-shaped slot 84 is etched on the front copper foil 8 of the radiation arm. This slot 84 can filter the radiation waves in the frequency band of 3300 MHz - 3800 MHz. The principle is that when the antenna in the filtering frequency band irradiates closely on the radiation arm, the induced currents on both sides of the C-shaped slot cancel each other out in the reverse direction, which can suppress the radiation of the induced current; the length of the slot C determines the filtering frequency band. The longer it is, the lower the filtering frequency band; the length of the slot C is about one-fourth of the wavelength of the filtering frequency point.

[0039] Inverted L-shaped branches 85 are provided at the edges of the copper foils 8 on both the front and back sides of the radiation arm. These branches 85 are also used to filter the radiation waves in the frequency band of 3300 MHz - 3800 MHz. The principle is that the induced current on the inverted L-shaped branch 85 and the induced current of the main body of the copper foil on the radiation arm can cancel each other out in the reverse direction in the filtering frequency band, suppressing the radiation. The length of the inverted L-shaped branch 85 determines the filtering frequency band. The longer the inverted L-shaped branch, the lower the filtering frequency band; the length is about one-eighth to one-fourth of the wavelength of the filtering frequency point.

[0040] As shown in Figures 4 - 7 are the schematic diagrams of the first balun 2 and the second balun 3. Protruding branches 9 are provided on both baluns. A first card slot 21 is opened on the first balun 2, and a second card slot 31 is provided on the second balun 3. The first balun 2 and the second balun 3 are orthogonally nested through the first card slot 21 and the second card slot 31; a feeding microstrip line 10 is provided on the front of the balun, and a metal ground 11 is provided on the back; the feeding microstrip line 10 is responsible for transmitting the energy fed into from the bottom of the balun; the end of the feeding microstrip line 10 is a short-circuit metallized via 12, which is responsible for transmitting the energy of the feeding microstrip line 10 to the metal ground 11 on the back of the balun, and the received metal ground 11 finally transmits the energy to the top radiation arm through the rectangular feeding piece 6 to complete the radiation. This coupling feeding method can broaden the working bandwidth of the antenna itself and is beneficial to impedance matching.

[0041] As shown in Figures 8 and 9, there are schematic diagrams of the front and back of the balun base 1. Four nearly rectangular mounting grooves 13 and four circular mounting holes 14 are provided on the balun base 1. A metal ground 15 is also printed on the back. The bottoms of the first balun 2 and the second balun 3 are inserted into the mounting grooves 13. The mounting grooves 13 can prevent the feeding microstrip line 10 from being short-circuited with the metal ground 15 on the back of the balun base 1; the metal ground 11 on the back of the balun is welded to the metal ground 15 on the back of the balun base 1, which physically plays the role of installing and fixing the balun, and achieves the effect of balanced feeding in terms of performance; the circular mounting holes 14 are used to install and fix the antenna, and the antenna is installed by fixing parts such as rivets.

[0042] The antenna in this embodiment operates in a frequency band of 690 MHz to 960 MHz. Without affecting its own radiation function, it can reduce radiation interference and shielding in other civilian communication frequency bands, and is highly versatile and practical in the integration of multi-band, multi-standard antennas. Furthermore, it pioneered the integration of multiple filtering and decoupling technologies into a single antenna, achieving dual-band decoupling while also extending the filtering bandwidth.

[0043] The foregoing descriptions of specific exemplary embodiments of the present invention are for purposes of illustration and description. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is apparent that many variations and modifications are possible in light of the foregoing teachings. The exemplary embodiments have been selected and described for the purpose of explaining the specific principles of the invention and their practical application, thereby enabling those skilled in the art to realize and utilize a variety of exemplary embodiments of the invention and various options and modifications. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A new type of dual-frequency filtering antenna, characterized by: The invention comprises a base, a group of baluns cross-arranged on the base, and a first radiating arm and a second radiating arm connected to the group of baluns, the front and back sides of the first radiating arm and the second radiating arm are printed with copper foil, the copper foil is divided into a plurality of small modules, and a connecting module is further arranged between each small module, a C-shaped gap is opened on the front side of each small module, and an inverted L-shaped branch is arranged at the edge.

2. A novel dual-frequency filtering antenna according to claim 1, characterized in that: The copper foil is provided with a plurality of metallized vias, and the metallized vias connect the copper foils on the front side and the back side.

3. The novel dual-frequency filtering antenna according to claim 1, characterized in that: The connection module is a zigzag module, which is used to electrically connect two adjacent small modules.

4. The novel dual-frequency filtering antenna according to claim 1, characterized in that: A feeding microstrip line is provided on the front side of the balun, and a metal ground is provided on the back side.

5. The novel dual-frequency filtering antenna according to claim 4 is characterized in that: The end of the feeding microstrip line is provided with a via hole, and the via hole passes through the metal ground.

6. The novel dual-frequency filtering antenna according to claim 4 is characterized in that: Two copper foils are arranged near the center of the front sides of the first radiation arm and the second radiation arm, and the top of the balun metal ground is connected to the two copper foils.

7. The novel dual-frequency filtering antenna according to claim 4 is characterized in that: The metal ground also uses copper foil.

8. The novel dual-frequency filtering antenna according to claim 1, characterized in that: There are two baluns, namely a first balun and a second balun, and the first balun and the second balun are orthogonally arranged on the base.

9. The novel dual-frequency filtering antenna according to claim 1, characterized in that: The antenna is used to filter out radiation waves in the frequency bands of 1710MHz-2690MHz and 3300MHz-3800MHz.

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