A dual-polarization multi-layer patch filter antenna and communication equipment

Abstract

The present invention discloses a dual-polarization multilayer patch filter antenna and communication equipment, comprising four layers of dielectric substrates, a metal reflector and a feeding probe, wherein the four layers of dielectric substrates comprise, from top to bottom, a first layer of dielectric substrate, a second layer of dielectric substrate, a third layer of dielectric substrate and a fourth layer of dielectric substrate, wherein the upper surface of the first layer of dielectric substrate is a main radiation patch, and the lower surface thereof is an X-shaped parasitic patch, the upper surface of the second layer of dielectric substrate is a first annular parasitic patch, and the lower surface thereof is a second annular parasitic patch, the upper surface of the third layer of dielectric substrate is a third annular parasitic patch, the upper surface of the fourth layer of dielectric substrate is a feeding circuit floor, and the lower surface thereof is a differential feeding circuit, and the metal reflector is arranged below the third layer of dielectric substrate and located on the upper surface of the feeding circuit floor; the filtering antenna does not comprise a filtering circuit, and the filtering characteristics are all generated by a parasitic manner, so it has a higher roll-off characteristic and a lower passband loss.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and in particular to a dual-polarization multi-layer patch filter antenna and communication equipment. Background Art

[0002] With the development of wireless communication technology, the requirements for communication systems tend to be miniaturized and highly integrated, and the requirements for antenna units are also getting higher and higher. In 5G technology, the loss of wireless base stations has greatly increased compared to previous generations of communication systems. In order to reduce energy consumption, it is necessary to reduce energy loss at all levels. For dual-polarized antenna units, polarization isolation and high roll-off characteristics must be achieved.

[0003] In recent years, the design of filtering antennas can be simply summarized into the following three categories. The first design is to coordinate the design of the filter with the antenna feeding part or to simply cascade the filter and the traditional antenna through an impedance transformer. The second design is to make slits and holes in the patch antenna or add metal probes to make the radiator itself have filtering characteristics. The third design is to add non-radiative parasitic structures to make the antenna radiation produce a filtering effect. This type of filtering antenna can greatly reduce transmission loss and reduce energy loss in the passband, which meets the requirements of 5G wireless communications and is also conducive to miniaturization and integration. Summary of the invention

[0004] In order to overcome the shortcomings and deficiencies of the prior art, the present invention provides a dual-polarized multilayer patch filter antenna and communication equipment. The present invention includes a multilayer parasitic structure and adopts differential feeding, thereby realizing a filter antenna with high roll-off characteristics including the 5G frequency band 3.4-3.7GHZ on the basis of good polarization isolation performance.

[0005] The present invention adopts the following technical solution:

[0006] A dual-polarization multilayer patch filter antenna, comprising four layers of dielectric substrates, a metal reflector and a feeding probe, wherein the four layers of dielectric substrates comprise, from top to bottom, a first dielectric substrate, a second dielectric substrate, a third dielectric substrate and a fourth dielectric substrate, wherein the upper surface of the first dielectric substrate is a main radiation patch, and the lower surface thereof is an X-shaped parasitic patch, the upper surface of the second dielectric substrate is a first annular parasitic patch, and the lower surface thereof is a second annular parasitic patch, the upper surface of the third dielectric substrate is a third annular parasitic patch, the upper surface of the fourth dielectric substrate is a feeding circuit floor, and the lower surface thereof is a differential feeding circuit, and the metal reflector is arranged below the third dielectric substrate and located on the upper surface of the feeding circuit floor;

[0007] The feeding probes are respectively connected to the X-shaped parasitic patch, the first annular parasitic patch, the second annular parasitic patch, the third annular parasitic patch and the differential feeding circuit.

[0008] The main radiation patch is a square patch with a hollow middle, and the hollow part is a square.

[0009] The four endpoints of the X-shaped parasitic patch pass through the gap and are coupled with the feeding probe.

[0010] The first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch are all square annular structures, and branches are respectively led out from four corners of the square annular structure to be connected to the feeding probe.

[0011] A circular through hole is provided in the middle of the metal reflection plate for the feeding probe to pass through.

[0012] There are four feeding probes, all of which are vertically arranged.

[0013] The differential feeding circuit includes two one-to-two power dividers, each of which includes a 50-ohm line width microstrip line and an impedance matching adjustment microstrip line with adjustable length and width. The impedance matching adjustment microstrip line is connected to a feeding probe, and the feeding probe is connected to another feeding probe on the same diagonal line through a 180-degree phase difference adjustment microstrip line.

[0014] The edges of the metal reflector plate stand upright.

[0015] In the present invention, the first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch have different sizes.

[0016] A communication device comprises the dual-polarization multi-layer patch filter antenna.

[0017] Beneficial effects of the present invention:

[0018] (1) The size of the filter antenna is controllable. The size of the cut-off part in the middle of the radiation patch can be adjusted as needed to control the size of the filter antenna. In this design, the antenna size is 0.23 ;

[0019] (2) This filtering antenna does not contain a filtering circuit, and the filtering characteristics are all generated by parasitic means, so it has a higher roll-off characteristic and lower passband loss, which can effectively reduce the energy loss of the 5G base station on the radiating antenna and reduce the base station operating cost;

[0020] (3) The present invention adopts a simple differential feeding power divider to reduce unnecessary losses, and the differential feeding method can bring better polarization isolation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a structural diagram of the main radiation patch of the present invention;

[0023] Figure 3 is a schematic diagram of the X-shaped parasitic patch structure of the present invention;

[0024] Figure 4 is a schematic diagram of the structure of the first annular parasitic patch of the present invention;

[0025] Figure 5 is a schematic diagram of the structure of the second annular parasitic patch of the present invention;

[0026] Figure 6 is a schematic diagram of the structure of the third annular parasitic patch of the present invention;

[0027] Figure 7 It is a schematic structural diagram of the metal reflector of the present invention;

[0028] Figure 8 It is a structural schematic diagram of the feeder circuit floor of the present invention;

[0029] Fig. 9 It is a structural schematic diagram of a differential feeding circuit of the present invention;

[0030] Fig.10 It is the reflection coefficient S11-frequency result diagram simulated by the present invention;

[0031] Fig.11 It is a transmission coefficient S21-frequency result diagram of the simulation of the present invention;

[0032] Fig.12 is the actual gain-frequency result diagram of the simulation of the present invention;

[0033] Fig.13 It is a graph of actual gain-azimuth angle theta results simulated by the present invention. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0035] Example

[0036] like Figure 1 As shown, a dual-polarized multilayer patch filter antenna has a symmetrical structure and is linearly polarized at ±45°.

[0037] It comprises four dielectric substrates 1, which are arranged at a certain distance and are symmetrical about the center. From top to bottom, they are the first dielectric substrate, the second dielectric substrate, the third dielectric substrate and the fourth dielectric substrate.

[0038] The upper surface of the first dielectric substrate is the main radiation patch 2, and the lower surface thereof is the X-shaped parasitic patch 3; the upper surface of the second dielectric substrate is the first annular parasitic patch 4, and the lower surface thereof is the second annular parasitic patch 5; the upper surface of the third dielectric substrate is the third annular parasitic patch 6; the upper surface of the fourth dielectric substrate is the feed circuit floor 8, and the lower surface thereof is the differential feed circuit 9; the metal reflector 7 is arranged below the third dielectric substrate and is located on the upper surface of the feed circuit floor 8.

[0039] like Figure 2 As shown, the main radiation patch is symmetrical in shape, completing the energy radiation of the filtering antenna. In this embodiment, the main radiation patch is a square, the middle of the square is hollowed out, and the hollowed-out part 10 is a square, so that the current path is lengthened and the antenna size is miniaturized.

[0040] The angle of the X-shaped parasitic patch is 90 degrees. The four endpoints of the X-shaped parasitic patch are coupled with four feeding probes 11 through a gap of 0.03 mm, respectively, and a weaker filtering zero point can be formed on the basis of feeding the main radiation patch.

[0041] like Figure 3-Figure 6 As shown, the first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch are all square annular structures. In this embodiment, the sizes of the three annular parasitic patches are different, and the size of the first annular parasitic patch is smaller than that of the third annular parasitic patch and smaller than that of the second annular parasitic patch. Each annular parasitic patch leads to four microstrip lines connected to four feeding probes.

[0042] In this embodiment, the three layers of annular parasitic patches have different sizes, each generating a stronger parasitic zero point. By adjusting the size of the parasitic patch, the position of the parasitic zero point can be moved so that one of the parasitic zero points is located on the left side of the passband and the other three parasitic zero points are located on the right side of the passband, thereby realizing a high roll-off characteristic of the filtering antenna, and adjusting the weaker filtering zero point generated by the X-shaped parasitic patch to the right edge of the passband, thereby realizing a low-loss design on the right edge of the passband, and the other zero points are located on the right side of the passband, thereby achieving better out-of-band suppression.

[0043] The present invention generates four parasitic zero points, the positions of which are relatively independently controlled by four parasitic patches, the resonant frequency of the parasitic patch corresponds to the frequency position of the parasitic filter zero point, and the position of the filter zero point can be moved by adjusting the size of the parasitic patch.

[0044] like Figure 7 As shown, the metal reflector is made of aluminum material. Its edges stand up to adjust the beam width and front-to-back ratio of the antenna unit. Four holes corresponding to the positions of the feeding probes are dug out on the metal reflector, and the metal feeding probes pass through them and are connected to the differential circuit of the lower layer to ensure signal transmission.

[0045] like Figure 8 As shown, at the position where the hole is dug in the metal reflector plate, a circular hole of corresponding size is also dug out of the feed circuit floor, and a feed probe is passed through the middle to input the differential signal from the feed circuit into the filter antenna.

[0046] like Fig. 9 As shown, the differential feeding circuit includes two one-to-two 0-degree and 180-degree phase power dividers; each power divider can be divided into three parts: a 50-ohm microstrip connecting line 12, an impedance matching adjustment microstrip line 13, and a 180-degree phase difference adjustment microstrip line 14. The output signals of the power divider are respectively connected to a pair of feeding probes on two diagonal lines to complete the generation of differential signals.

[0047] The various layers of the structure of the present invention are connected by four feeding probes located on the diagonal lines of the main radiation patch, which are completely symmetrical about the center of the antenna main patch; the signal is transmitted from the metal probes to the four layers of parasitic patches through a pair of differential feeding circuits with almost identical performance, and then coupled to the upper main radiation patch through the dielectric substrate under the uppermost dielectric substrate to complete the radiation of the antenna.

[0048] In addition, the present invention can simultaneously parasitize a plurality of parasitic units of different shapes or the same shape under the main parasitic patch, and the parasitic mode can be coupled parasitic or directly connected to the feeding probe.

[0049] like Figure 10-11 As shown, it is a simulation result diagram of the reflection coefficient S11-frequency and actual gain-frequency of the positive and negative 45-degree dual-polarization filter antenna provided by an embodiment of the present invention. The impedance matching in the passband is good, the impedance bandwidth is 3.3-3.8GHz, the return loss is less than -15dB, and the gain in the common frequency band is about 6.5dB. Both sides of the passband have high roll-off filtering characteristics, achieving out-of-band suppression of more than 12dB in 0-3.1GHz and more than 13.5dB in 4-4.7GHz.

[0050] like Fig.12 As shown, it is a transmission coefficient S21-frequency simulation result diagram of a positive and negative 45 degree dual-polarization filter antenna provided by an embodiment of the present invention. The isolation between the two ports in the passband is good, both below -30dB.

[0051] like Fig.13As shown, it is a result diagram of the actual gain peak realized gain-azimuth angle theta of the positive and negative 45 degree dual-polarization filter antenna provided by an embodiment of the present invention. In the passband 3.34-3.82GHz, the 3dB beam width is between 89.6-78.99°, which can meet the base station antenna oscillator wave width requirement.

[0052] A communication device comprises a transmitting system and a receiving system constituted by the present invention.

[0053] The embodiments provided by the present invention can adjust the size of the relevant structure according to the needs to adapt to the receiving and transmitting devices of wireless communication systems of different frequency bands. Due to the filtering characteristics of the present invention, it is particularly suitable for open and complex communication scenarios. At the same time, benefiting from the integration of filtering characteristics and radiation characteristics, the communication equipment constituted by the present invention is also suitable for the integration and integration of wireless mobile communications.

[0054] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A dual-polarized multilayer patch filter antenna, characterized in that: The invention comprises four layers of dielectric substrates, a metal reflector and a feeding probe, wherein the four layers of dielectric substrates comprise a first dielectric substrate, a second dielectric substrate, a third dielectric substrate and a fourth dielectric substrate in order from top to bottom, the upper surface of the first dielectric substrate is a main radiation patch, and the lower surface thereof is an X-shaped parasitic patch, the upper surface of the second dielectric substrate is a first annular parasitic patch, and the lower surface thereof is a second annular parasitic patch, the upper surface of the third dielectric substrate is a third annular parasitic patch, the upper surface of the fourth dielectric substrate is a feeding circuit floor, and the lower surface thereof is a differential feeding circuit, and the metal reflector is arranged below the third dielectric substrate and located on the upper surface of the feeding circuit floor; The feeding probe is respectively connected to the X-shaped parasitic patch, the first annular parasitic patch, the second annular parasitic patch, the third annular parasitic patch and the differential feeding circuit; The main radiation patch is a square patch with a hollow middle, and the hollowed-out part is a square; The four endpoints of the X-shaped parasitic patch pass through the gap and are coupled with the feeding probe.

2. A dual-polarization multilayer patch filter antenna according to claim 1, characterized in that: The first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch are all square annular structures, and branches are respectively led out from four corners of the square annular structure to be connected to the feeding probe.

3. A dual-polarization multi-layer patch filter antenna according to claim 1, characterized in that: A circular through hole is provided in the middle of the metal reflection plate for the feeding probe to pass through.

4. A dual-polarization multilayer patch filter antenna according to any one of claims 1 to 3, characterized in that: There are four feeding probes, all of which are vertically arranged.

5. The dual-polarization multi-layer patch filter antenna according to claim 1, characterized in that: The differential feeding circuit includes two one-to-two power dividers, each of which includes a 50-ohm line width microstrip line and an impedance matching adjustment microstrip line with adjustable length and width. The impedance matching adjustment microstrip line is connected to a feeding probe, and the feeding probe is connected to another feeding probe on the same diagonal line through a 180-degree phase difference adjustment microstrip line.

6. The dual-polarization multi-layer patch filter antenna according to claim 1, characterized in that: The edges of the metal reflector plate stand upright.

7. The dual-polarization multi-layer patch filter antenna according to claim 1, characterized in that: The first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch have different sizes.

8. A communication device, characterized in that: The communication device comprises the dual-polarization multi-layer patch filter antenna according to any one of claims 1 to 7.

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