A cable-free feeding multi-frequency antenna and a base station antenna

Abstract

The application discloses a cable-free feeding multi-frequency antenna and a base station antenna, which comprises a reflecting plate, a plurality of double-frequency coaxial radiation units arranged above the reflecting plate, and a plurality of cavity assemblies arranged below the reflecting plate, wherein the top surface of the cavity assemblies is outwardly convex and provided with a low-frequency output port and a high-frequency output port; a single double-frequency coaxial radiation unit comprises a connecting plate, a high-frequency balun assembly and a low-frequency balun assembly; the connecting plate is provided with a fitting part one connected with the high-frequency balun assembly, a fitting part two connected with the low-frequency balun assembly, and a fitting part three connected with the low-frequency output port and the high-frequency output port; a feeding line microstrip is arranged on the connecting plate, and the high-frequency balun assembly and the low-frequency balun assembly are respectively electrically connected with the high-frequency output port and the low-frequency output port through the feeding line microstrip; thus, the integration of the double-frequency coaxial radiation unit and the plurality of cavity assemblies is realized, the feeding network is greatly simplified, the overall integration degree is high, the space occupation is small, and high performance can be considered.

Description

Technical Field

[0001] This invention relates to the field of mobile communication technology, and in particular to a cable-free multi-frequency antenna and base station antenna. Background Technology

[0002] With the rapid development of mobile communication networks, especially the full deployment of fifth-generation mobile communication technology (5G) and the pre-research and development of sixth-generation mobile communication technology (6G), the coexistence of multiple frequency bands and multiple standards has become the norm. In order to save site resources, it is usually necessary to integrate antennas of multiple frequency bands into the same antenna, that is, a multi-frequency antenna, in order to achieve multi-frequency common aperture radiation.

[0003] In existing technologies, feed networks largely rely on coaxial cables. Typically, multiple cavity phase shifters are independently installed below the reflector, and then the coaxial cables lead to the radiating elements above the reflector. This feed network is complex and inefficient to assemble. When there are numerous frequency bands, the feed lines become cumbersome. The current antenna design, consisting of cavity phase shifters combined with coaxial cables and radiating elements, results in a wide variety of parts, inconsistent cable lengths, and tedious manual soldering processes, making automated assembly difficult and leading to poor product consistency. Furthermore, existing low-frequency and high-frequency feed components are usually separated and independently arranged. Cables require reserved bending radii and routing space, resulting in cluttered wiring on the back and front of the reflector, occupying a large space, and hindering further reduction in the overall antenna size, thus limiting multi-frequency integration. Moreover, cables have unit-length loss, and redundant assembly length further increases insertion loss. Solder joints and cable connections are significant sources of passive intermodulation (PIM), affecting signal purity at high power levels and limiting power output. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a reasonably structured cable-free multi-frequency antenna and base station antenna, thereby achieving integrated direct connection between the dual-frequency coaxial radiating unit and the multi-cavity assembly. This greatly simplifies the power supply network, reduces the overall size, and achieves high integration, small space occupation, and high performance.

[0005] The technical solution adopted in this invention is as follows: A cable-free multi-frequency antenna includes a reflector. Multiple dual-frequency coaxial radiating elements are disposed above the reflector, and a multi-cavity assembly is disposed below the reflector. The top surface of each multi-cavity assembly protrudes to form a low-frequency output port and a high-frequency output port. Each dual-frequency coaxial radiating element includes a connecting plate, a high-frequency balun assembly, and a low-frequency balun assembly. The connecting plate has a mounting part one for connecting to the high-frequency balun assembly, a mounting part two for connecting to the low-frequency balun assembly, and a mounting part three for connecting to the low-frequency and high-frequency output ports. A feed line microstrip is disposed on the connecting plate, electrically connecting the high-frequency and low-frequency balun assemblies to the high-frequency and low-frequency output ports, respectively.

[0006] As a further improvement to the above technical solution: The microstrip power supply line on the connection board includes independent high-frequency and low-frequency feeders. The high-frequency feeder is equipped with a high-frequency input port, which is electrically connected to the high-frequency output port and the high-frequency balun component. The low-frequency feeder is equipped with a low-frequency input port, which is electrically connected to the low-frequency output port and the low-frequency balun component.

[0007] The reflector plate has through holes, and the connecting plate is connected to the multi-cavity assembly through the through holes.

[0008] The multi-cavity assembly includes a housing mounted on the bottom surface of the reflector, with multiple cavities inside the housing. Each cavity contains a stripline phase-shifting assembly corresponding to a high frequency or a low frequency. The stripline fed by the corresponding stripline phase-shifting assembly has an upwardly protruding low-frequency output port and a high-frequency output port.

[0009] A single dual-frequency coaxial radiating unit also includes a high-frequency radiator and a low-frequency radiator. The high-frequency radiator is installed on top of the high-frequency balun assembly, and the low-frequency radiator is installed on top of the low-frequency balun assembly. The low-frequency balun assembly is installed through the high-frequency radiator. The bottom ends of the high-frequency balun assembly and the low-frequency balun assembly are jointly installed on a connecting plate. The high-frequency balun assembly and the low-frequency balun assembly are each arranged vertically and intersected to form an angle. The vertical center line of the high-frequency balun assembly coincides with the vertical center line of the low-frequency balun assembly.

[0010] The low-frequency balun component has a downward groove at the center of its bottom, and the high-frequency balun component has an upward groove at the center of its top. The high-frequency balun component is cross-fitted into the downward groove of the low-frequency balun component from bottom to top, and the upward groove of the high-frequency balun component is fitted into the top of the downward groove. The high-frequency radiator has a through slot I that runs vertically through its center, and the outward-protruding structure at the top of the high-frequency balun component is fitted into through slot I. Through slot II are spaced apart on the high-frequency radiators located on both sides of through slot I, and the two downward-facing ends of the low-frequency balun components located on both sides of the downward groove pass through through slot II respectively.

[0011] It also includes high-frequency radiating units, which are arranged at intervals with dual-frequency coaxial radiating units and on the same straight line to form a row of antenna arrays. The row of antenna arrays corresponds to the same group of multi-channel cavity components.

[0012] The high-frequency radiation unit includes a connecting plate and a high-frequency balun assembly. One end of the high-frequency balun assembly is fitted with a high-frequency radiator, and the other end of the high-frequency balun assembly is fitted with a connecting plate. The connecting plate electrically connects the high-frequency balun assembly to the high-frequency output port of the multi-cavity assembly via a microstrip feed line.

[0013] The antenna array has two or more rows spaced apart on the top surface of the reflector, and an isolation plate is provided on the reflector between adjacent rows of antenna arrays; the bottom surface of the reflector is equipped with multi-channel cavity components that are arranged corresponding to each row of antenna arrays.

[0014] A base station antenna, comprising any of the above-mentioned cable-free fed multi-frequency antennas.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention uses a connecting plate as a structural support while integrating a microstrip power supply line, realizing a direct connection between the upper dual-frequency coaxial radiation unit and the lower multi-cavity assembly. This eliminates the need for all coaxial cables, shortens the signal transmission path to the geometric shortest distance, greatly simplifies the power supply network, reduces the overall size, and achieves high integration, small space occupation, and high performance.

[0016] The present invention also includes the following advantages: By integrating direct connection settings, all cables and solder joints are eliminated, significantly reducing intermodulation distortion sources and effectively ensuring signal purity of the system at high power. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure 2 for Figure 1 A magnified view of a portion of point A in the middle.

[0019] Figure 3 This is an exploded view of the present invention.

[0020] Figure 4 This is a side view of the present invention.

[0021] Figure 5 This is a schematic diagram of the assembly of the multi-cavity assembly and the connecting plate of the present invention.

[0022] Figure 6 This is an exploded view of the dual-frequency coaxial radiation unit of the present invention (low-frequency radiators are omitted).

[0023] The components include: 1. Reflector; 2. Isolation plate; 3. Dual-frequency coaxial radiation unit; 4. High-frequency radiation unit; 5. Multi-channel cavity assembly. 11. Through hole; 31. Connecting plate; 32. High-frequency balun assembly; 33. Low-frequency balun assembly; 34. High-frequency radiator; 35. Low-frequency radiator; 311. Mounting part one; 312. Mounting part two; 313. Mounting part three; 314. High-frequency input port; 315. Low-frequency input port; 321. Insertion part one; 322. Outward protrusion structure; 323. Upper groove; 331. Lower groove; 332. Insertion part two; 341. Through slot one; 342. Through slot two; 51. Low-frequency output port; 52. High-frequency output port. Detailed Implementation

[0024] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0025] like Figure 1 , Figure 2 and Figure 3 As shown, this embodiment of a cable-free fed multi-frequency antenna includes a reflector 1, a plurality of dual-frequency coaxial radiating elements 3 arranged above the reflector 1, and a multi-cavity assembly 5 arranged below the reflector 1. The top surface of the multi-cavity assembly 5 protrudes outwards and has a low-frequency output port 51 and a high-frequency output port 52, as shown below. Figure 5 As shown; a single dual-frequency coaxial radiation unit 3 includes a connecting plate 31, a high-frequency balun assembly 32, and a low-frequency balun assembly 33. The connecting plate 31 is provided with a mounting part 311 that connects to the high-frequency balun assembly 32, a mounting part 312 that connects to the low-frequency balun assembly 33, and a mounting part 313 that connects to the low-frequency output port 51 and the high-frequency output port 52. The connecting plate 31 is provided with a feed line microstrip, which electrically connects the high-frequency balun assembly 32 and the low-frequency balun assembly 33 to the high-frequency output port 52 and the low-frequency output port 51, respectively.

[0026] In this embodiment, the connecting plate 31 serves as a structural support while integrating a microstrip power supply line, realizing a direct connection between the upper dual-frequency coaxial radiation unit 3 and the lower multi-cavity assembly 5, eliminating the need for all coaxial cables and shortening the signal transmission path to the geometric shortest distance.

[0027] In this embodiment, the integrated direct connection eliminates all cables and solder joints, significantly reducing intermodulation distortion sources and effectively ensuring the signal purity of the system under high power.

[0028] The microstrip power supply line on the connecting plate 31 includes independent high-frequency feeders and low-frequency feeders. The high-frequency feeder is provided with a high-frequency input port 314, which is electrically connected to the high-frequency output port 52 and the high-frequency balun component 32. The low-frequency feeder is provided with a low-frequency input port 315, which is electrically connected to the low-frequency output port 51 and the low-frequency balun component 33.

[0029] In the dual-frequency coaxial radiation unit 3, the low-frequency balun component 33 and the high-frequency balun component 32 are both fed to the same connecting plate 31, which realizes the unification of ground potential and is conducive to improving impedance matching and frequency isolation. Furthermore, the connecting plate 31 is equipped with multiple wiring to realize the branching of high and low frequency feeds without increasing the additional board area.

[0030] The reflector plate 1 has a through hole 11, and the connecting plate 31 is connected to the multi-cavity assembly 5 through the through hole 11 to form a passage.

[0031] like Figure 4 and Figure 5 As shown, the multi-cavity assembly 5 includes a housing mounted on the bottom surface of the reflector 1. Multiple cavities are provided in the housing. Each cavity is equipped with a stripline phase shifting assembly corresponding to a high frequency or a low frequency. The stripline fed by the corresponding stripline phase shifting assembly is provided with an upwardly protruding low-frequency output port 51 and a high-frequency output port 52, forming a corresponding low-frequency cavity assembly and a high-frequency cavity assembly.

[0032] In this embodiment, the low-frequency cavity assembly and the high-frequency cavity assembly adopt an integrated structural design, fixed as a whole module to the back of the reflector 1. This integrated multi-cavity assembly 5 simultaneously integrates low-frequency and high-frequency stripline phase-shifting structures, changing the signal phase through a sliding medium to achieve beam downtilt. Compared to traditional independently installed multiple cavities, this effectively reduces the number of parts, simplifies the installation process, and unifies the feed reference ground for both low-frequency and high-frequency cavities.

[0033] like Figure 2 and Figure 6 As shown, a single dual-frequency coaxial radiation unit 3 also includes a high-frequency radiator 34 and a low-frequency radiator 35. The high-frequency radiator 34 is installed on the top of the high-frequency balun assembly 32, and the low-frequency radiator 35 is installed on the top of the low-frequency balun assembly 33. The low-frequency balun assembly 33 is installed through the high-frequency radiator 34. The bottom ends of the high-frequency balun assembly 32 and the low-frequency balun assembly 33 are jointly installed on the connecting plate 31. The high-frequency balun assembly 32 and the low-frequency balun assembly 33 are each arranged vertically and intersected to form an angle. The vertical center line of the high-frequency balun assembly 32 coincides with the vertical center line of the low-frequency balun assembly 33.

[0034] The dual-frequency coaxial radiation unit 3 in this embodiment realizes the single balun cross coaxial structure setting of high and low frequency radiation units, which effectively simplifies the overall structure, reduces assembly complexity, improves and ensures production efficiency and production consistency, and effectively compresses the axial and radial space occupation.

[0035] By using a cross-coaxial physical layout, the high-frequency and low-frequency radiating elements share the same spatial axis, effectively compressing the projected area of ​​the radiating elements on the reflector 1, achieving a compact common-aperture layout, and helping to improve the miniaturization of multi-band antennas.

[0036] The low-frequency balun component 33 has a lower groove 331 facing upward at the bottom center, and the high-frequency balun component 32 has an upper groove 323 facing downward at the top center. The high-frequency balun component 32 is cross-fitted into the lower groove 331 of the low-frequency balun component 33 from bottom to top, and the upper groove 323 of the high-frequency balun component 32 is fitted into the top of the lower groove 331.

[0037] In this embodiment, the independent low-frequency balun component 33 and high-frequency balun component 32 are connected to the connecting plate 31 via the upper groove 323 and the lower groove 331 to achieve coaxial assembly between them.

[0038] A through slot 341 is provided in the middle of the high-frequency radiator 34, and the top protruding structure 322 of the high-frequency balun component 32 is fitted into the through slot 341. Through slots 342 are provided on both sides of the high-frequency radiator 34. The two ends of the low-frequency balun component 33 located on both sides of the lower groove 331 pass through the through slots 342.

[0039] In this embodiment, the low-frequency balun component 33, the high-frequency balun component 32, the low-frequency radiator 35, the high-frequency radiator 34, and the connecting plate 31 can all be manufactured using PCB (printed circuit board) technology; the high-frequency radiator 34 is electrically connected to the corresponding high-frequency balun component 32 by soldering, and the low-frequency radiator 35 is electrically connected to the corresponding low-frequency balun component 33 by soldering.

[0040] In one embodiment, the bottom end of the high-frequency balun assembly 32 extends downward to form an insertion portion 321, which is fitted to the fitting portion 311 of the connecting plate 31. The two downward-facing ends of the low-frequency balun assembly 33 located on both sides of the lower groove 331 extend downward to form insertion portions 332, which are fitted to the fitting portions 312 of the connecting plate 31.

[0041] It also includes a high-frequency radiating unit 4, which is arranged at intervals with the dual-frequency coaxial radiating unit 3 and is located on the same straight line to form a row of antenna arrays. The row of antenna arrays corresponds to the same group of multi-channel cavity components 5. The same group of multi-channel cavity components 5 simultaneously serve the row of antenna arrays corresponding to the front of the reflector 1, including low-frequency arrays and high-frequency arrays.

[0042] The high-frequency radiation unit 4 includes a connecting plate 31 and a high-frequency balun assembly 32. One end of the high-frequency balun assembly 32 is fitted with a high-frequency radiator 34, and the other end of the high-frequency balun assembly 32 is fitted with a connecting plate 31. The connecting plate 31 connects the high-frequency balun assembly 32 to the high-frequency output port 52 in the multi-cavity assembly 5 via a microstrip feed line.

[0043] The antenna array has two or more rows spaced apart on the top surface of the reflector 1. An isolation plate 2 is provided on the reflector 1 between adjacent rows of antenna arrays to improve port isolation. A multi-channel cavity assembly 5 is installed on the bottom surface of the reflector 1, which is arranged corresponding to each row of antenna array.

[0044] In this embodiment, multiple rows of antenna arrays are arranged side by side. Each row of antenna array consists of an integrated cavity combined with a dual-frequency array dual-frequency coaxial radiation unit 3 and a high-frequency radiation unit 4, which can realize flexible expansion of more frequency bands or more channels. Moreover, the interfaces of all modules are standardized and the installation method is consistent. When expansion is required, similar modules are added to the reflector 1 at the same spacing. The multi-channel cavity assembly 5 is fixed with a uniform screw hole array, and the connection method remains unchanged.

[0045] In this embodiment, the multi-frequency antenna only needs to accommodate the integrated multi-cavity assembly 5 on the back of the reflector 1. The dual-frequency coaxial radiation unit 3 and the high-frequency radiation unit 4 on the front are arranged in a straight line with low frequency and high frequency. Furthermore, the high frequency and low frequency in the dual-frequency coaxial radiation unit 3 share a common connecting plate 31. The total thickness of the antenna can be compressed to less than 80% of that of existing antennas, which is conducive to dense deployment.

[0046] This embodiment also proposes a base station antenna, including any of the above-mentioned cable-free fed multi-frequency antennas.

[0047] The multi-frequency antenna of this invention eliminates the need for all coaxial cables, shortens the signal transmission path to the geometric shortest distance, greatly simplifies the power supply network, reduces the overall size, and achieves high integration, small space occupation, and high performance.

[0048] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0049] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A cable-free, multi-frequency antenna, comprising a reflector (1), characterized in that: Multiple dual-frequency coaxial radiation units (3) are provided above the reflector (1), and a multi-channel cavity assembly (5) is provided below the reflector (1). The top surface of the multi-channel cavity assembly (5) is provided with a low-frequency output port (51) and a high-frequency output port (52). A single dual-frequency coaxial radiation unit (3) includes a connecting plate (31), a high-frequency balun assembly (32), and a low-frequency balun assembly (33). The connecting plate (31) is provided with a mounting part one (311) that connects to the high-frequency balun assembly (32), a mounting part two (312) that connects to the low-frequency balun assembly (33), and a mounting part three (313) that connects to the low-frequency output port (51) and the high-frequency output port (52). The connecting plate (31) is provided with a feed line microstrip, which electrically connects the high-frequency balun assembly (32) and the low-frequency balun assembly (33) to the high-frequency output port (52) and the low-frequency output port (51), respectively.

2. The cable-free multi-frequency antenna as described in claim 1, characterized in that: The microstrip power supply line on the connecting plate (31) includes an independent high-frequency feeder and a low-frequency feeder. The high-frequency feeder is provided with a high-frequency input port (314), which is electrically connected to the high-frequency output port (52) and the high-frequency balun assembly (32). The low-frequency feeder is provided with a low-frequency input port (315), which is electrically connected to the low-frequency output port (51) and the low-frequency balun assembly (33).

3. The cable-free multi-frequency antenna as described in claim 1, characterized in that: The reflector (1) has a through hole (11), and the connecting plate (31) is connected to the multi-cavity assembly (5) through the through hole (11).

4. The cable-free multi-frequency antenna as described in claim 1, characterized in that: The multi-cavity assembly (5) includes a housing mounted on the bottom surface of the reflector (1), and multiple cavities are provided in the housing. Each cavity is provided with a stripline phase shifting assembly corresponding to a high frequency or a low frequency. The stripline fed by the corresponding stripline phase shifting assembly is provided with an upwardly protruding low-frequency output port (51) and a high-frequency output port (52).

5. A cable-free, multi-frequency antenna as described in claim 1, characterized in that: Each dual-frequency coaxial radiation unit (3) also includes a high-frequency radiator (34) and a low-frequency radiator (35). The high-frequency radiator (34) is installed on the top of the high-frequency balun assembly (32), and the low-frequency radiator (35) is installed on the top of the low-frequency balun assembly (33). The low-frequency balun assembly (33) is installed through the high-frequency radiator (34). The bottom ends of the high-frequency balun assembly (32) and the low-frequency balun assembly (33) are installed together on the connecting plate (31). The high-frequency balun assembly (32) and the low-frequency balun assembly (33) are each arranged vertically and intersected to form an angle. The vertical center line of the high-frequency balun assembly (32) coincides with the vertical center line of the low-frequency balun assembly (33).

6. A cable-free, multi-frequency antenna as described in claim 5, characterized in that: The low-frequency balun component (33) has a lower groove (331) facing upward at the bottom center, and the high-frequency balun component (32) has an upper groove (323) facing downward at the top center. The high-frequency balun component (32) is cross-fitted into the lower groove (331) of the low-frequency balun component (33) from bottom to top, and the upper groove (323) of the high-frequency balun component (32) is fitted into the top of the lower groove (331). The high-frequency radiator (34) has a through slot (341) that runs vertically through the middle, and the convex structure (322) at the top of the high-frequency balun component (32) is fitted into the through slot (341). The high-frequency radiator (34) located on both sides of the through slot (341) has a through slot (342) spaced apart, and the two lower ends of the low-frequency balun component (33) located on both sides of the lower groove (331) pass downward through the through slot (342).

7. A cable-free, multi-frequency antenna as described in claim 1, characterized in that: It also includes a high-frequency radiation unit (4), which is arranged and positioned on the same straight line with the high-frequency radiation unit (4) and the dual-frequency coaxial radiation unit (3) to form a row of antenna arrays, and the row of antenna arrays corresponds to the same group of multi-channel cavity components (5).

8. A cable-free, multi-frequency antenna as described in claim 7, characterized in that: The high-frequency radiation unit (4) includes a connecting plate (31) and a high-frequency balun assembly (32). One end of the high-frequency balun assembly (32) is fitted with a high-frequency radiator (34), and the other end of the high-frequency balun assembly (32) is fitted with a connecting plate (31). The connecting plate (31) electrically connects the high-frequency balun assembly (32) to the high-frequency output port (52) of the multi-channel cavity assembly (5) via a microstrip feed line.

9. A cable-free, multi-frequency antenna as described in claim 7, characterized in that: The antenna array has two or more rows spaced apart on the top surface of the reflector (1), and an isolation plate (2) is provided on the reflector (1) between adjacent rows of antenna arrays; the bottom surface of the reflector (1) is equipped with a multi-channel cavity assembly (5) corresponding to each row of antenna arrays.

10. A base station antenna, characterized in that: The cable-free fed multi-frequency antenna includes any one of claims 1-9.

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