Low-cost dual-polarization electric scanning base station antenna applied to 5G communication

Abstract

The invention provides a low-cost dual-polarization electric scanning base station antenna applied to 5G communication, and provides an effective method for the design of a low-cost electric control scanning base station antenna. According to the invention, an antenna array surface is formed based on 2-bit dual-polarized microstrip antenna units, the antenna array surface and a feed network are in plug-in connection, and the feed phase of each antenna unit is controlled through an external wave control circuit board, so that phased wave beam scanning is realized. The base station antenna has the beneficial effects that compared with a traditional fixed beam base station antenna, the coverage range of the base station antenna can be effectively expanded; according to the invention, the microstrip antenna units are separated from each other and are not printed on a whole dielectric plate, so that the array scale can be flexibly controlled according to actual requirements; the antenna unit integrates two functions of radiation and phase shift, so that an external phase shifter is omitted, and the processing, assembling and maintenance costs are greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of phased array antennas, and in particular proposes an effective method for designing low-cost, electrically controllable scanning dual-polarized base station antennas. Background Technology

[0002] With the rapid development of mobile communication technology and the increasing complexity of communication scenarios, users' demands for network coverage, speed, and stability are constantly rising. This places higher requirements on the performance and cost of base station antennas. Traditional base station antennas use a fixed beam design, resulting in limited coverage and high deployment and maintenance costs. In contrast, phased array antennas, with their advantages of flexible beam adjustment, fast scanning, and wide-area coverage, have become a key technology for 5G base stations. However, traditional phased array antennas rely on external phase shifters, leading to complex hardware, high power consumption, and relatively high cost, limiting large-scale commercial use. To address this limitation, this invention uses a digital bit antenna element as a carrier and, for base station antenna applications, implements an electrically controllable scanning dual-polarized antenna with advantages such as low cost and wide coverage. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a low-cost, electrically controllable scanning dual-polarized base station antenna design method.

[0004] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0005] A low-cost dual-polarized electronically scanned base station antenna for 5G communication has an overall structure comprising an antenna array (1) and a feed network (2). The antenna array (1) is composed of N 2-bit dual-polarized microstrip antenna elements arranged in a certain manner, where N represents the number of array elements. The feed network (2) is located directly below the antenna array and is connected to the antenna array via a blind-plug RF connector. Each microstrip antenna element is independently plugged into the feed network, rather than being printed on a single dielectric substrate. The external beam control circuit board controls the switching of each antenna element between four phase states: 0°, 90°, 180°, and 270° to achieve beam scanning.

[0006] As a preferred method, the arrangement of the 2-bit dual-polarized microstrip antenna elements in the antenna array (1) is one of the following: rectangular grid, triangular grid, circular array, hexagonal array, hollow array, or sparse array.

[0007] As a preferred embodiment, the overall structure of the 2-bit dual-polarized microstrip antenna unit is divided into a radiating patch section and a phase-shifting feed section. The radiating patch section consists of a driving patch (4), an upper parasitic patch (5), and a lower parasitic patch (6). The driving patch (4) is printed on the front side of a dielectric substrate (7). The back side of the dielectric substrate (7) is a metal ground (8), and coupling gaps (13) are etched on the metal ground (8) to couple the feed energy to the driving patch (4). The parasitic patch is mounted on top of the driving patch (4) by a fixing component, with air between them. The upper and lower parasitic patches are printed on the front and back sides of a dielectric substrate (9), respectively. The phase-shifting feed section is printed on the back side of a dielectric substrate (10), and the DC bias lines (11) controlling the PIN diodes P1~P4 are also printed on this layer. The dielectric substrate (10) and the dielectric substrate (7) are bonded together by a layer of prepreg (12).

[0008] As a preferred embodiment, the driving patch (4) and the lower parasitic patch (6) are shaped like a circle, a square, or other polygons with more than four sides; the upper parasitic patch (5) is shaped like a ring, a square ring, or other polygonal rings with more than four sides.

[0009] As a preferred method, the drive patch (4) is fed using a slot coupling method. Two slots (13) on the metal ground (8) are located at the two corners of the radiating patch. The two polarizations are fed by the "corner feeding" method. Taking one polarization as an example, when the patch is fed at one corner, the polarization direction of the synthesized wave is along the diagonal direction of the patch, that is, a +45° or -45° polarized wave is formed.

[0010] As a preferred embodiment, the coupling gap (13) is shaped as an "H", a rectangle or a variant thereof.

[0011] As a preferred approach, one of the following methods can be used in the antenna element: geometric perturbation, multi-feed method, or multi-element method, to form dual circular polarization.

[0012] As a preferred approach, the phase-shifting feed section can simultaneously achieve phase shifting and feeding for +45° and -45° polarization, with the phase-shifting feed structures corresponding to the two polarizations being completely identical. The phase-shifting feed network consists of a 1-bit feed rectangular ring (14) and a 90° phase shifter (15), which achieve a 2-bit phase distribution for the antenna element through cascaded phase shifting. The 1-bit feed rectangular ring (14) integrates two anti-parallel PIN diode switches P1 and P2. The current flow on the rectangular ring is controlled by these two switches. If the two diodes are not turned on at the same time, the switching between 0° and 180° phase states can be achieved. The 90° phase shifter (15) contributes an additional 90° phase, and it also integrates two parallel PIN diodes P3 and P4. The two switches can be turned on or off at the same time to achieve the switching between 0° and 90° phase states. The four phases, 0° and 180°, and 0° and 90°, are combined to form a controllable 2-bit phase distribution of 0°, 90°, 180°, and 270°.

[0013] As a preferred embodiment, the 90° phase shifter (15) is one of the following: a reflective phase shifter, a switch-line phase shifter, a high-pass / low-pass filter phase shifter, a loaded-line phase shifter, a directional coupler phase shifter, or a balanced phase shifter.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. In this invention, the individual microstrip antenna elements that make up the antenna array are independent of each other and are not printed on a single dielectric substrate. This helps to suppress mutual coupling between elements, thereby improving array gain. It also makes it easy to disassemble and maintain in a targeted manner, reducing processing costs, and allows for flexible control of the array size according to actual needs.

[0016] 2. In this invention, the antenna array (1) and the feed network (2) are connected by a blind-plug RF connector (3). This eliminates the PCB pressing process between the feed network (2) and the antenna array (1), improves the processing success rate, and reduces the processing cost. On the other hand, it facilitates the targeted disassembly and maintenance of the antenna unit and makes it convenient to solder the semiconductor devices on the back of the antenna unit.

[0017] 3. This invention constructs a 2-bit dual-polarized microstrip antenna unit that integrates the functions of "radiation" and "phase shifting" into the antenna unit, realizing phase shifting of the antenna unit while radiating. Compared with the traditional phased array with external phase shifters, it greatly reduces the processing and maintenance costs.

[0018] 4. This invention proposes an electrically controllable scanning dual-polarized base station antenna, which can flexibly switch between beams at different angles, and significantly expands the antenna's coverage range compared with traditional fixed-beam base station antennas. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a low-cost dual-polarized electronically scanned base station antenna for 5G communication according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the stacked structure of the 2-bit dual-polarized microstrip antenna unit of the present invention;

[0021] Figure 3 yes Figure 2 The reflection coefficient and isolation curves of the dual-polarized antenna element with +45° polarization are shown.

[0022] Figure 4 yes Figure 2 The 2-bit phase distribution curve of the dual-polarized antenna element is shown when it is polarized at +45°.

[0023] Figure 5 yes Figure 1 The simulation results of the radiation performance of the dual-polarized base station antenna in the XOZ plane are shown. Its main polarization is +45° polarization, and the scanning elevation angles are 0°, 15°, and 30°, respectively, corresponding to a frequency of 1.97 GHz.

[0024] Figure 6 yes Figure 1 The simulation results of the radiation performance of the dual-polarized base station antenna in the XOZ plane are shown. Its main polarization is -45° polarization, and the scanning elevation angles are 0°, 15°, and 30°, respectively, corresponding to a frequency of 1.97 GHz.

[0025] Figure 7 yes Figure 1 The simulation results of the radiation performance of the dual-polarized base station antenna in the XOZ plane are shown. Its main polarization is +45° polarization, and the scanning elevation angles are 0°, 15°, and 30°, respectively, corresponding to a frequency of 2.16 GHz.

[0026] Figure 8 yes Figure 1 The simulation results of the radiation performance of the dual-polarized base station antenna in the XOZ plane are shown. Its main polarization is -45° polarization, and the scanning elevation angles are 0°, 15°, and 30°, respectively, corresponding to a frequency of 2.16 GHz. Detailed Implementation

[0027] The following specific examples illustrate an implementation method of a low-cost dual-polarized electronically scanned base station antenna for 5G communication proposed in this invention.

[0028] like Figure 1As shown, a low-cost dual-polarized electronically scanned base station antenna for 5G communication comprises an antenna array (1) and a feed network (2). The antenna array (1) consists of 16 2-bit dual-polarized microstrip antenna elements arranged in a triangular grid pattern. The feed network (2) is responsible for dividing the feed signal into multiple equal-amplitude and in-phase radio frequency signals to power each antenna element. An external beam control circuit board can control each antenna element to flexibly switch between four different phase states: 0°, 90°, 180°, and 270°, thereby achieving phased beam scanning. In the antenna array, the 2-bit dual-polarized microstrip antenna elements are separate from each other, rather than printed on a single dielectric substrate. The antenna array (1) and the feed network (2) are connected by a blind-plug radio frequency connector (3).

[0029] like Figure 2 As shown, the overall structure of the 2-bit dual-polarized microstrip antenna unit is divided into a radiating patch section and a phase-shifting feed section. The radiating patch section consists of a driving patch (4), an upper parasitic patch (5), and a lower parasitic patch (6). The square driving patch (4) is printed on the front side of a dielectric substrate (7). The back side of the dielectric substrate (7) is a metal ground (8). The "H"-shaped gap (13) on the ground is used to couple the feed energy to the driving patch (4). The parasitic patch is mounted on top of the driving patch (4) by a fixing component, with air between them. The upper parasitic patch (5) is a square ring, and the lower parasitic patch (6) is square. The upper and lower parasitic patches are printed on the front and back sides of a dielectric substrate (9), respectively. The phase-shifting feed section is printed on a dielectric substrate (10), and the DC bias lines (11) controlling the PIN diodes P1~P4 are also printed on this layer. The dielectric substrate (10) of the phase-shifting feed section and the dielectric substrate (7) of the drive patch (4) are bonded together by a layer of prepreg (12).

[0030] like Figure 2 As shown, the drive patch (4) is fed using a slot coupling method. Two slots (13) on the metal ground (8) are located at the two corners of the radiating patch. The two polarizations are fed by the "corner feeding" method. Taking one polarization as an example, when the patch is fed at one corner, the polarization direction of the synthesized wave is along the diagonal direction of the patch, that is, a +45° or -45° polarized wave is formed.

[0031] like Figure 2As shown, the phase-shifting feed section can simultaneously achieve phase shifting and feeding for +45° and -45° polarization, and the phase-shifting feed structures corresponding to the two polarizations are exactly the same. The phase-shifting feed network consists of a 1-bit feed rectangular ring (14) and a 3-dB reflective 90° phase shifter (15). The two achieve a 2-bit phase distribution of the antenna element through cascaded phase shifting. The 1-bit feed rectangular ring (14) integrates two anti-parallel PIN diode switches P1 and P2. The current flow on the rectangular ring is controlled by these two switches. If the two diodes are not turned on at the same time, the switching between 0° and 180° phase states can be achieved. The 3-dB reflective 90° phase shifter (15) contributes an additional 90° phase. It also integrates two parallel PIN diodes P3 and P4. The two switches are turned on or off at the same time to achieve the switching between 0° and 90° phase states. The four phases, 0° and 180°, and 0° and 90°, are combined to form a controllable 2-bit phase distribution of 0°, 90°, 180°, and 270°.

[0032] Assuming the switch is on (state 1) and off (state 0), the correspondence between the 2-bit phase of the antenna element and the switch state is as follows:

[0033] phase P1~P4 0° 0111 90° 0100 180° 1011 270° 1000

[0034] In this example, to verify the feasibility of the 2-bit dual-polarized microstrip antenna element designed in this invention, the S-parameters and phase distribution of the antenna element were verified using numerical simulation software. For example... Figure 3 As shown, the impedance bandwidth of the 2-bit dual-polarized microstrip antenna element designed in this invention can cover 1.91-2.18 GHz, and the dual-polarization isolation within this bandwidth is greater than 28 dB. Figure 4 As shown, within the bandwidth, this antenna element can achieve a 2-bit phase distribution.

[0035] In this example, to verify the feasibility of the low-cost dual-polarized electronically scanned base station antenna designed for 5G communication according to the present invention, the beam scanning characteristics of the antenna were verified using numerical simulation software. Figure 5 and Figure 6 As shown, the frequency is 1.97 GHz, and the scanning angles for +45° and -45° polarization are 0°, 15°, and 30°, respectively; Figure 7 and Figure 8 As shown, the frequency is 2.16 GHz, and the scanning angles for +45° polarization and -45° polarization are 0°, 15°, and 30°, respectively.

[0036] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A low-cost dual-polarized electronically scanned base station antenna for 5G communication, characterized in that, The overall structure of the antenna includes an antenna array (1) and a feeding network (2). The antenna array (1) is composed of N 2-bit dual-polarized microstrip antenna elements arranged in a certain way, where N represents the number of array elements. The feeding network (2) is located directly below the antenna array and is connected to the antenna array through a blind-plug RF connector. Each microstrip antenna element is independently plugged into the feeding network instead of being printed on a single dielectric substrate. The external beam control circuit board controls each antenna element to switch between four phase states: 0°, 90°, 180°, and 270° to achieve beam scanning.

2. The low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 1, characterized in that, The 2-bit dual-polarized microstrip antenna elements in the antenna array (1) are arranged in one of the following ways: rectangular grid, triangular grid, circular array, hexagonal array, hollow array, or sparse array.

3. The low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 1, characterized in that, The overall structure of the 2-bit dual-polarized microstrip antenna unit is divided into a radiating patch part and a phase-shifting feed part. The radiating patch part consists of a driving patch (4), an upper parasitic patch (5), and a lower parasitic patch (6). The driving patch (4) is printed on the front side of a dielectric substrate (7). The back side of the dielectric substrate (7) is a metal ground (8), and coupling gaps (13) are etched on the metal ground (8). The parasitic patch is mounted on the driving patch (4) by a fixing component, and there is air between the two. The upper and lower parasitic patches are printed on the front and back sides of a dielectric substrate (9), respectively. The phase-shifting feed part is printed on the back side of a dielectric substrate (10). The DC bias lines (11) of the control PIN diodes P1~P4 are also printed on this layer. The dielectric substrate (10) and the dielectric substrate (7) are bonded together by a layer of prepreg (12).

4. A low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 3, characterized in that, The driving patch (4) and the lower parasitic patch (6) are shaped like a circle, a square, or other polygons with more than four sides; the upper parasitic patch (5) is shaped like a ring, a square ring, or other polygonal rings with more than four sides.

5. A low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 3, characterized in that, The coupling gap (13) is in the shape of an "H", a rectangle or a variant thereof.

6. A low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 3, characterized in that, By employing one of the following methods in the antenna element: geometric perturbation, multi-feed method, or multi-element method, dual circular polarization can be achieved.

7. A low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 3, characterized in that, The phase-shifting feed network consists of a 1-bit feed rectangular ring (14) and a 90° phase shifter (15), which are cascaded to achieve 2-bit phase control of the antenna unit. The 1-bit feed rectangular ring (14) integrates two anti-parallel PIN diode switches P1 and P2, and the 90° phase shifter (15) integrates two parallel PIN diodes P3 and P4. The two polarizations of the phase-shifting feed network are completely identical.

8. A low-cost dual-polarized electronically scanned base station antenna for 5G communication according to claim 7, characterized in that, The 90° phase shifter (15) is one of the following: reflective phase shifter, switch-line phase shifter, high-pass / low-pass filter phase shifter, loaded-line phase shifter, directional coupler phase shifter, and balanced phase shifter.

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