A dual-polarized filter antenna, an array antenna, and a wireless communication device

Abstract

The application discloses a dual-polarized filtering antenna, an array antenna and a wireless communication device, wherein the radiation patch layer comprises a radiation patch loaded with a short-circuit column and an etching groove, a parasitic resonator is loaded around the radiation patch, an open-circuit stub is arranged on the parasitic stub matching layer, the metal ground layer is a reference ground plane of the dual-polarized filtering antenna, and a dual-polarized differential feeding network is arranged on the feeding line layer. The application has the advantages of small volume, mature processing technology, cost saving, wide bandwidth, good filtering performance, and the like. When the array antenna is composed, wide-angle beam scanning can be realized, and the application requirements of millimeter wave communication devices can be met.

Description

Technical Field

[0001] This invention relates to the field of communications, and in particular to a dual-polarized filter antenna, an array antenna, and a wireless communication device. Background Technology

[0002] Millimeter-wave mobile communication is a strategic area of ​​focus for my country's development. Compared to the Sub-6GHz band, the millimeter-wave band offers lower latency and abundant spectrum resources, meeting the needs of high-bandwidth hotspot applications. It not only enhances the communication experience of civilian terminals but also facilitates technological upgrades for strategic scenarios such as the Industrial Internet. In practice, filters are often integrated with the antenna at the transceiver front end to suppress image frequency interference, intermediate frequency leakage, higher harmonics, and interference from other systems. However, this approach increases size and introduces significant insertion loss, degrading performance and making integration with the chip into the system difficult. Therefore, integrating the filtering function directly into the antenna structure, without introducing additional filtering circuitry, is beneficial for further improving the performance of both the antenna and the overall system.

[0003] Furthermore, phased array technology is one of the key technologies in the development of millimeter-wave communication. By utilizing beamforming, spatial multiplexing, and spatial diversity technologies of phased array antennas, it can significantly improve spectrum efficiency, system capacity, coverage effect, and anti-interference capability to meet the needs of a large number of users in the Internet of Things, thereby achieving characteristics such as high speed and large capacity. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the present invention aims to provide a dual-polarized filter antenna, an array antenna, and a wireless communication device.

[0005] This invention achieves high roll-off gain suppression outside the passband without affecting the performance of the antenna itself, while also expanding the beamwidth of the antenna elements, enabling good scanning performance in array antennas.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A dual-polarized filter antenna comprises, from top to bottom, a parasitic patch layer, a radiating patch layer, a parasitic stub matching layer, a metallic ground layer, and a feed line layer, wherein the above functional layers are connected by a dielectric substrate.

[0008] The parasitic patch layer is provided with parasitic patches, and the radiating patch layer includes radiating patches and parasitic resonators. The parasitic patches and radiating patches form a stacked patch. Outside the high-frequency band, due to the dominant role of electrical coupling, anti-phase currents are generated on the parasitic patches and radiating patches, which cancel each other out in the far-field radiation, generating a first radiation null point. The radiating patch is slotted, and the slot changes the electromagnetic coupling between the parasitic patch and the radiating patch from electrical coupling to magnetic coupling, thereby controlling the first radiation null point to move from high frequency to low frequency.

[0009] Furthermore, the radiating patch has a slot, which includes a cross-shaped slot and four rectangular slots.

[0010] Furthermore, the four rectangular slots are respectively located at the ends of the cross-shaped slot. The rectangular slots connect the radiating patch layer to the metal ground layer through short-circuit posts. The short-circuit posts are equivalent to parallel inductors between the radiating patch and the metal ground. Based on the anti-phase current of the stacked patch, the current intensity on the radiating patch is further reduced, the roll-off performance of the first radiation null point is enhanced, and vertical current is introduced to expand the beamwidth and enhance the beam scanning performance of the array antenna after arraying.

[0011] Furthermore, the parasitic resonator is a half-wavelength open-circuit resonator or a quarter-wavelength short-circuit resonator. The parasitic resonator is coupled to the radiating patch, which is equivalent to a series resonator coupled to the radiating patch. When the parasitic resonator operates at the resonant frequency, it absorbs all energy, which suppresses the radiation of the radiating patch, achieves band-stop performance, and generates a second radiation zero at the passband edge.

[0012] Furthermore, the parasitic stub matching layer includes four open-circuit stubs, which are loaded on the feeding metal pillars to adjust the matching and control the current at the resonant frequency so that it cannot be fed into the radiating patch normally, thus preventing the radiating patch from radiating normally and generating a third radiation null point.

[0013] Furthermore, differential pairs are set at ±45 degrees diagonally on the radiating patch, and are excited by the two single-polarization differential feed networks of the feed line layer respectively to achieve dual polarization.

[0014] Furthermore, the radiation patch and the parasitic patch are arranged as a single rectangle, a chamfered rectangle, or multiple rectangles.

[0015] Furthermore, the metal ground layer is provided with circular holes to isolate it from the feeder cable layer.

[0016] An array antenna includes N×M dual-polarized filter antennas as described above, where N and M are natural numbers.

[0017] A wireless communication device includes the array antenna described above.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0019] 1. The stacked structure of this invention is simple, can be designed with a variety of processing techniques, has a wide bandwidth, good filtering performance, and can be applied in many scenarios. It can achieve the working mode of one chip driving multiple antennas by adjusting the power supply network, thereby reducing the number of chips and saving costs.

[0020] 2. This invention transforms the electrical coupling of the multilayer patch itself into magnetic coupling by using etching grooves and loading short-circuit posts, thereby shifting the high roll-off radiation zero point from high frequency to low frequency. At the same time, by utilizing the resonance of various structures, it achieves good filtering performance without introducing additional filtering circuits.

[0021] 3. This invention utilizes the loaded short-circuit post to introduce vertical current, thereby expanding the beamwidth of the antenna element. Based on this, a large-scale phased array antenna can achieve wide-angle beam scanning, meeting the market demand for millimeter-wave communication. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0024] Figure 2 This is an exploded view of the structure of the dual-polarized filter antenna of Embodiment 1 of the present invention.

[0025] Figure 3 This is a schematic diagram of the shape of the parasitic patch in Embodiment 1 of the present invention.

[0026] Figure 4 This is an optimized diagram of the radiating patch layer structure of the dual-polarized filter antenna according to Embodiment 1 of the present invention.

[0027] Figure 5 This is a structural diagram of the parasitic stub matching layer of the dual-polarized filter antenna in Embodiment 1 of the present invention.

[0028] Figure 6 This is a diagram of the metal ground plane structure of the dual-polarized filter antenna in Embodiment 1 of the present invention.

[0029] Figure 7 This is a simulation result diagram of the S-parameters of the dual-polarized filter antenna of Embodiment 1 of the present invention.

[0030] Figure 8 This is a simulation result of the gain of the dual-polarized filter antenna in Embodiment 1 of the present invention.

[0031] Figure 9 This is a simulation result of the radiation pattern of the dual-polarized filter antenna in Embodiment 1 of the present invention.

[0032] Figure 10 This is a structural diagram of a 2×2 array of dual-polarized filter antennas according to Embodiment 2 of the present invention.

[0033] Figure 11 This is a simulation result of the active return loss of the 2×2 dual-polarized filter antenna array in Embodiment 2 of the present invention.

[0034] Figure 12 This is a simulation result of the gain of the 2×2 dual-polarized filter antenna array in Embodiment 2 of the present invention.

[0035] Figure 13 This is a simulation result of the radiation pattern of the 2×2 array of dual-polarized filter antennas in Embodiment 2 of the present invention when it is not scanning.

[0036] Figure 14 This is a simulation result of the radiation pattern during scanning of the 2×2 array of the dual-polarized filter antenna in Embodiment 2 of the present invention.

[0037] Among them, 1-parasitic patch layer, 11-parasitic patch, 2-radiating patch layer, 21-radiating patch, 22-cross-shaped groove, 23-rectangular groove, 24-short-circuit post, 25-C-type stub, 26-W-type stub, 3-parasitic stub matching layer, 31-open stub, 4-metal ground layer, 41-isolation circular hole, 5-feeder line layer, 61-first dielectric substrate, 62-second dielectric substrate, 63-third dielectric substrate, 64-fourth dielectric substrate. Detailed Implementation

[0038] To make the objectives of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0039] In the description of the embodiments of this application, it should be understood that the terms "vertical", "up", "down", "around", "height", "long", "short", "end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description, and do not indicate or imply that the device or element referred to must have a specific position, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this application.

[0040] Furthermore, unless otherwise explicitly specified and limited, the terms "load," "connect," "introduce," "bend," etc., should be interpreted broadly. For example, they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0041] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0042] Example 1

[0043] like Figures 1-2 As shown, this embodiment provides a dual-polarized filter antenna, including a parasitic patch layer 1, a radiating patch layer 2, a parasitic stub matching layer 3, a metal ground layer 4, and a feed line layer 5 distributed from top to bottom. The functional layers are connected by a PCB dielectric substrate. The dielectric substrate includes a first dielectric substrate 61, a second dielectric substrate 62, a third dielectric substrate 63, and a fourth dielectric substrate 64 connected together to form a robust packaging architecture that can be used for testing.

[0044] Furthermore, the PCB substrate is made of high-frequency board material with adjustable height.

[0045] Furthermore, each functional layer may be composed of a multilayer dielectric substrate and a multilayer metal layer.

[0046] This application provides a dual-polarized filter antenna, such as... Figure 2 As shown, the parasitic patch layer is disposed on top of the radiating patch layer. The radiating patch layer includes a radiating patch 21 and a parasitic resonator. The parasitic patch layer has a parasitic patch, and the radiating patch is etched with a cross-shaped groove and four rectangular grooves. The rectangular grooves connect the radiating patch layer 2 to the metal ground layer 4 through short-circuit posts 24, which are bendable. The cross-shaped groove and rectangular grooves change the main form of electromagnetic coupling between the parasitic patch and the radiating patch from electrical coupling to magnetic coupling, thereby controlling the first radiation null point to shift from high frequency to low frequency.

[0047] Furthermore, the center point of the cross-shaped slot coincides with the center point of the radiating patch, and four rectangular slots are respectively set at the ends of the cross-shaped slot. The short-circuit post is loaded on the extension line of the cross-shaped slot. The short-circuit post is equivalent to a parallel inductor between the radiating patch and the metal ground. Based on the anti-phase current of the stacked patch, the current intensity on the radiating patch is further reduced, the roll-off performance of the first radiation null point is enhanced, and at the same time, vertical current is introduced to expand the beamwidth and enhance the beam scanning performance of the array antenna after arraying.

[0048] Optional, such as Figure 3 As shown, the parasitic patch is specifically a metal patch, and the patch can take many forms, such as a single rectangular patch 11, a single truncated rectangular patch, or an arrangement of multiple small rectangular patches.

[0049] Figure 4 The figure shows an optimized schematic diagram of the radiating patch layer 2. The four feed metal pillars port1+, port1-, port2+, and port2- on the radiating patch 21 provide two pairs of differential pairs, corresponding to ±45° polarization. They are excited by the two single-polarization differential feed networks of the feed line layer to achieve dual polarization.

[0050] The differential pair refers to two feed ports in the same polarization direction, with a 180° phase difference between the two ports, in order to achieve good polarization isolation performance.

[0051] Furthermore, the radiating patch 21 and the parasitic patch 11 are coupled to each other, generating two resonant points in the operating frequency band, expanding the antenna impedance bandwidth, and improving the antenna gain in the passband. Since the coupling method is mainly electrical coupling, the radiating patch 21 and the parasitic patch 11 generate antiphase currents outside the high-frequency passband, which cancel each other out in the far field radiation, generating the first radiation null point Null#1.

[0052] Furthermore, the radiating patch 2 has a cross-shaped groove 22 and four rectangular grooves 23, which changes the main electromagnetic coupling mode of the stacked patch from electrical coupling to magnetic coupling. By adjusting the length and width of the grooves, the first radiation zero point can be moved to a lower frequency. At the same time, loading the rectangular grooves 23 can make the size of the grooves smaller.

[0053] Furthermore, four short-circuit posts 24 are loaded on the extension line of the cross-shaped slot 22, which can further reduce the current intensity on the radiating patch 21 on the basis of the anti-phase current of the stacked patch, enhance the roll-off performance of the first radiation null point, and introduce vertical current to expand the beamwidth and enhance the beam scanning performance of the array antenna after arraying.

[0054] Furthermore, a parasitic resonator is loaded around the radiating patch 21. The parasitic resonator is specifically a half-wavelength open-circuit resonator or a quarter-wavelength short-circuit resonator, and its shape can be in the form of a C-type stub 25, a W-type stub 26, etc. The resonance of this parasitic resonator can be equivalent to a series resonance coupled with the radiating patch 21. When resonating, the parasitic resonator absorbs all energy, which leads to the suppression of radiation from the radiating patch, achieving band-stop performance and generating a second radiation zero point Null#2 at the passband edge, forming a good out-of-band suppression effect.

[0055] Optionally, the radiation patch is specifically a metal patch, which can take many forms, such as a single rectangular patch or a single truncated rectangular patch.

[0056] Optionally, the cross-shaped groove 22 and the rectangular groove 23 can be bent.

[0057] like Figure 5 As shown, four open-circuit stubs 31 are arranged on the parasitic stub matching layer 3. These four open-circuit stubs are loaded on the feeding metal pillar to optimize antenna matching. At the same time, the current cannot be properly fed into the radiating patch 21 at the resonant frequency, causing the radiating patch 21 to fail to radiate normally, generating a third radiation null point Null#3. Figure 8 As shown, the third radiation null point is near 40 GHz, achieving good bandpass performance.

[0058] Optionally, the end of the open stub 31 can be bent. In this embodiment, the open stub is rectangular and the four open stubs are symmetrical about the center point of the antenna.

[0059] The open-circuit stubs are all of equal length and each is equal to half a wavelength.

[0060] like Figure 6 As shown, the metal ground layer 4 has four circular holes 41 that form an isolation between it and the power supply structure.

[0061] Figure 7 This is a graph showing the S-parameter results of the dual-polarized filter antenna in this embodiment, where |S 11 |、|S 22 | represents the return loss of ports 1 and 2 with different polarizations, respectively, |S 12 | represents the polarization isolation between ports 1 and 2. As shown in the figure, the -10dB impedance bandwidth of antenna ports 1 and 2 can cover 24.25 to 29.5 GHz, and the polarization isolation in the passband is greater than 32dB.

[0062] Figure 8This is a gain result diagram of the dual-polarized filter antenna in this embodiment. As can be seen from the diagram, the antenna has a stable gain within the passband and three radiation nulls outside the passband. The gain suppression level in the 1-22.5 GHz range outside the passband is greater than 21 dB, the gain roll-off rate in the 22.5-23 GHz range reaches 64 dB / GHz, and the gain suppression level in the 37-41 GHz range outside the passband is greater than 9 dB, which can achieve good filtering performance.

[0063] Figure 9 This is the radiation pattern of the dual-polarized filter antenna in this embodiment at 27 GHz. As can be seen from the figure, the antenna's 3dB beamwidth is 86°, the cross-polarization ratio within ±45° is more than 25dB, and the overall radiation pattern has high symmetry.

[0064] Example 2:

[0065] like Figure 10 As shown, this embodiment provides a dual-polarization filter array antenna, including N×M dual-polarization filter antennas. In this embodiment, there are specifically 2×2 dual-polarization filter antennas. The two polarization ports of each filter antenna element are connected by separate differential feed networks.

[0066] Figure 11 This is a simulation result diagram of the active return loss of the dual-polarized filter array antenna in this embodiment. Active S(1:1), Active S(3:1), Active S(5:1), and Active S(7:1) represent the active S-parameters of ports 1, 3, 5, and 7 of the four antenna elements with the same polarization in the 2×2 array, respectively. As can be seen from the figure, the -10dB impedance bandwidth of the array antenna covers 24.25–29.5 GHz, covering the n257 / n258 / n261 frequency bands.

[0067] Figure 12 This is the gain curve of the dual-polarized filter array antenna in this embodiment. As can be seen from the figure, the gain of the array antenna is stable within the passband, the gain suppression level of 1-22.25GHz outside the passband is greater than 19dB, and the gain suppression level of 37-41GHz outside the passband is greater than 12dB.

[0068] Figure 13 and Figure 14 This is the radiation pattern of the dual-polarized filter array antenna in this embodiment when it is not scanning and when it is scanning at the center frequency of 27GHz. As can be seen from the figure, under the constraint of a large size, the vertical beam of the array antenna can be scanned to ±45 degrees, the gain drop does not exceed 3dB, and the cross-polarization ratio when not scanning and when scanning is greater than 18dB, indicating that the array antenna has good beam scanning performance.

[0069] Example 3:

[0070] A wireless communication device includes the aforementioned dual-polarized filter array antenna, wherein the array antenna includes N×M dual-polarized filter antennas, where N and M are natural numbers that can be flexibly adjusted according to the feeding network and chip design, enabling a one-chip-driven multi-antenna operating mode.

[0071] In summary, the stacked structure of this invention is simple and can be designed using various processing techniques. It allows for a single chip driving multiple antennas by adjusting the feed network, reducing the number of chips and saving costs. Through etching grooves and loading short-circuit posts, the electrical coupling dominance of the stacked patch itself is transformed into magnetic coupling dominance, shifting the high roll-off radiation null point from high to low frequencies. The loaded short-circuit posts introduce vertical current, expanding the antenna beamwidth. Utilizing various resonant structures, good filtering performance is achieved without introducing additional filtering circuitry. Based on this design, a large-scale phased array antenna can achieve wide-angle beam scanning, meeting the market demands of millimeter-wave communication.

[0072] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A dual polarized filtered antenna, characterized by, From top to bottom, the parasitic patch layer, the radiation patch layer, the parasitic stub matching layer, the metal ground layer and the feed line layer are connected by dielectric substrates; The parasitic patch layer is provided with a parasitic patch, the radiation patch layer includes a radiation patch and a parasitic resonator, the parasitic patch and the radiation patch form a laminated patch, and due to the dominant role of electric coupling, the parasitic patch and the radiation patch generate anti-phase current in the high-frequency band, which is radiated in the far field and is canceled out, thereby generating a first radiation zero point. The radiation patch is slotted, the slot includes a cross-shaped slot and four rectangular slots, the slot changes the form of electromagnetic coupling between the parasitic patch and the radiation patch from electric coupling to magnetic coupling, and adjusts the first radiation zero point to move from high frequency to low frequency. The four rectangular slots are respectively arranged at the ends of the cross-shaped slot, four short-circuit columns are loaded on the extension lines of the cross-shaped slot, and the short-circuit columns are not directly connected to the cross-shaped slot, thereby connecting the radiation patch layer and the metal ground layer, and the short-circuit columns are equivalent to a parallel inductance between the radiation patch and the metal ground. On the basis of the anti-phase current of the laminated patch, the current intensity on the radiation patch is further weakened, the roll-off performance of the first radiation zero point is enhanced, in addition, a vertical current is introduced, the bandwidth is expanded, and the beam scanning performance of the array antenna after arraying is enhanced.

2. The dual polarized filtered antenna according to claim 1, characterized in that, The parasitic resonator is a half-wavelength open-circuit resonator or a quarter-wavelength short-circuit resonator, the parasitic resonator is coupled with the radiation patch, equivalent to a series resonator coupled with the radiation patch, the parasitic resonator absorbs all energy when working at a resonant frequency, resulting in suppression of the radiation of the radiation patch, realizing band rejection performance, and generating a second radiation zero point at the edge of the passband.

3. The dual polarized filtered antenna of claim 1, wherein, The parasitic stub matching layer includes four open-circuit stubs, the open-circuit stubs are loaded on the feed metal column for adjusting matching, controlling the current at the resonant frequency to be unable to normally feed into the radiation patch, so that the radiation patch cannot normally radiate, thereby generating a third radiation zero point.

4. The dual polarized filtered antenna of claim 1, wherein, A differential pair is arranged on the diagonals of the radiation patch at ±45 degrees, and is excited by two single-polarization differential feed networks of the feed line layer, thereby realizing dual-polarization.

5. The dual polarized filtered antenna of claim 1, wherein, The radiation patch and the parasitic patch are single rectangular, cut-corner rectangular or multiple rectangular arrangements.

6. The dual polarized filtered antenna of claim 1, wherein, The metal ground layer is provided with a circular hole to form isolation with the feed line layer.

7. An array antenna, characterized by The array antenna includes N×M dual-polarized filtering antennas according to any one of claims 1-6, and N and M are natural numbers.

8. A wireless communication device, comprising: The array antenna includes the array antenna according to claim 7.

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