Dual-band omni-directional filter antenna with multiple radiation zeros based on open stub loading

Abstract

The application discloses a kind of based on open circuit branch loading multi-radiation zero point dual-frequency omnidirectional filtering antenna, the antenna adopts three-layer medium substrate structure, through the multi-structure coupling design of driving circular patch etching annular groove, parasitic circular patch, rectangular open circuit branch and circular arc T-shaped open circuit branch, realize dual-frequency omnidirectional radiation and multi-radiation zero point regulation.The annular groove generates third resonance point, fourth resonance point and fifth radiation zero point;Circular arc T-shaped open circuit branch introduces second radiation zero point and fourth radiation zero point, simultaneously generates second resonance point and fifth resonance point;Parasitic circular patch and driving patch coupling generate third radiation zero point and first resonance point;Rectangular open circuit branch introduces first radiation zero point.The application has dual-frequency omnidirectional radiation characteristics, wideband performance and multi-radiation zero point controllable characteristics, and is suitable for WiMAX / WLAN and other wireless communication scenarios.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a multi-radiation null dual-frequency omnidirectional filter antenna and wireless communication device based on open-stub loading. Background Technology

[0002] With the rapid development of wireless communication technology, users' demands for miniaturized, multifunctional, and high-performance communication equipment are constantly increasing. Filtered antennas, as an emerging technology, can improve the spectrum utilization and anti-interference capabilities of a system. However, existing filtered antennas are mostly side-emitting, making it difficult to meet the communication requirements of omnidirectional radiation. Most only support single-band operation, which is insufficient for dual-band communication scenarios. Furthermore, traditional filtered antennas have a limited number of radiating nulls and insufficient tuning capabilities, restricting further optimization of their filtering performance. The proposed multi-radiating null dual-band omnidirectional filtered antenna based on open-stub loading helps to achieve omnidirectional radiation, enhance out-of-band suppression capabilities, and improve adaptability to complex wireless environments. Summary of the Invention

[0003] The primary objective of this invention is to overcome the shortcomings and deficiencies of the prior art and provide a dual-frequency omnidirectional filtering antenna based on open-circuit stub loading with multiple radiation nulls. This antenna has a simple structure, achieves dual-frequency operation, and possesses omnidirectional radiation characteristics. Furthermore, by introducing multiple controllable radiation nulls, it effectively improves filtering performance and anti-interference capabilities, thus meeting the application requirements of modern communication equipment for multi-band, high-performance, and high-integration applications.

[0004] A second objective of the present invention is to provide a wireless communication device.

[0005] The first objective of this invention is achieved through the following technical solution: a multi-radiation null-point dual-frequency omnidirectional filtering antenna based on open-circuit stub loading, comprising a first dielectric substrate, a second dielectric substrate, a third dielectric substrate, a ground plane, a rectangular open-circuit stub, an arc-shaped T-shaped open-circuit stub, a coaxial probe, a driving circular patch, an annular groove, and a parasitic circular patch; the first dielectric substrate is stacked on top of the second dielectric substrate, the second dielectric substrate is stacked on top of the third dielectric substrate, the parasitic circular patch is disposed on the upper surface of the first dielectric substrate, the driving circular patch is disposed on the upper surface of the second dielectric substrate, and an annular groove concentric with the driving circular patch is formed on the driving circular patch, the rectangular open-circuit stub and the arc-shaped T-shaped open-circuit stub are disposed on the upper surface of the third dielectric substrate, the rectangular open-circuit stub is connected to the vertical side of the arc-shaped T-shaped open-circuit stub, the ground plane is disposed on the lower surface of the third dielectric substrate, and the coaxial probe sequentially passes through the ground plane, the third dielectric substrate, and the second dielectric substrate and connects to the driving circular patch.

[0006] Preferably, the driving circular patch and the parasitic circular patch are located on the same central axis.

[0007] Preferably, the antenna has five radiation nulls from low frequency to high frequency, which are the first radiation null, the second radiation null, the third radiation null, the fourth radiation null, and the fifth radiation null in order of frequency from low to high. The antenna has two resonant points in the low frequency band and three resonant points in the high frequency band, which are the first resonant point, the second resonant point, the third resonant point, the fourth resonant point, and the fifth resonant point in order of frequency from low to high.

[0008] Preferably, the rectangular open-circuit stub generates a first radiation null point, and the length of the rectangular open-circuit stub is one-quarter of the wavelength corresponding to the frequency of the first radiation null point. By controlling the length of the rectangular open-circuit stub, the left and right movement of the first radiation null point can be controlled.

[0009] Preferably, the arc-shaped T-shaped open stub generates a second radiation zero point and a fourth radiation zero point. The length of the arc-shaped T-shaped open stub is three-quarters of the wavelength corresponding to the frequency of the second radiation zero point, and the length of the arc-shaped T-shaped open stub is five-quarters of the wavelength corresponding to the frequency of the fourth radiation zero point. At the same time, a second resonant point and a fifth resonant point are generated. By controlling the length of the arc-shaped T-shaped open stub, the left and right movement of the second radiation zero point and the fourth radiation zero point can be controlled.

[0010] Preferably, the mutual coupling between the parasitic circular patch and the driving circular patch generates a third radiation zero point and a first resonant point. The left and right movement of the third radiation zero point can be controlled by controlling the size of the parasitic circular patch and the driving circular patch.

[0011] Preferably, a fifth radiation zero point is generated by etching an annular groove on the driving circular patch, and a third and fourth resonant points are generated simultaneously. The left and right movement of the fifth radiation zero point can be controlled by controlling the position of the annular groove.

[0012] Preferably, the rectangular open-circuit stub, the arc-shaped T-shaped open-circuit stub, the driving circular patch, the parasitic circular patch, and the ground are made of copper.

[0013] Preferably, the ground surface covers the entire lower surface of the third dielectric substrate.

[0014] The second objective of this invention is achieved through the following technical solution: a wireless communication device, including the above-mentioned multi-radiation null dual-frequency omnidirectional filtering antenna based on open-stub loading.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] 1. The antenna of this invention generates a third and fourth resonant point, and simultaneously a fifth radiation null, by slotting a drive circular patch; it generates a second and fourth radiation null, and simultaneously a second and fifth resonant point, by loading an arc-shaped T-shaped open-circuit stub; it generates a third radiation null, and simultaneously a first resonant point, by loading a parasitic circular patch; and it generates a first radiation null by loading a rectangular open-circuit stub. Ultimately, this antenna achieves dual-band omnidirectional filtering characteristics and excellent broadband performance.

[0017] 2. The antenna of this invention employs annular grooves etched on the driving circular patch, parasitic circular patches, rectangular open-circuit stubs, and arc-shaped T-shaped open-circuit stubs to realize a multi-radiation null-point dual-frequency omnidirectional filtering antenna based on open-circuit stub loading. The antenna has a low-frequency matching bandwidth of 9.1% (3.36-3.68GHz) and a high-frequency matching bandwidth of 15.6% (5.13-6GHz), satisfying broadband characteristics. The peak gains within the passband are 4.3dBi and 5.6dBi, respectively. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading according to an embodiment of the present invention.

[0019] Figure 2 This is a cross-sectional view of a multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading, according to an embodiment of the present invention.

[0020] Figure 3 This is a top view of the third dielectric substrate of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading according to an embodiment of the present invention.

[0021] Figure 4 This is a top view of the second dielectric substrate of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading according to an embodiment of the present invention.

[0022] Figure 5 This is a top view of the first dielectric substrate of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading according to an embodiment of the present invention.

[0023] Figure 6 The S-parameter diagram of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading is shown in an embodiment of the present invention.

[0024] Figure 7 This is a gain curve of a multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading, according to an embodiment of the present invention.

[0025] Figure 8 The radiation pattern of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in an embodiment of the present invention is shown in the E-plane radiation pattern at 3.5 GHz.

[0026] Figure 9 The radiation pattern of the H-plane of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in an embodiment of the present invention is shown at 3.5 GHz.

[0027] Figure 10 The radiation pattern of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in an embodiment of the present invention is shown in the E-plane radiation pattern at 5.5 GHz.

[0028] Figure 11 The radiation pattern of the H-plane of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in an embodiment of the present invention is shown at 5.5 GHz. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0030] Example 1

[0031] Currently, most existing filter antennas primarily emit side-firing radiation, making it difficult to meet the communication requirements of omnidirectional radiation. Most only support single-band operation, failing to meet the needs of dual-band communication scenarios. Furthermore, traditional filter antennas have a limited number of radiating nulls and insufficient tuning capabilities, restricting further optimization of their filtering performance. This embodiment discloses a multi-radiating null dual-band omnidirectional filter antenna based on open-circuit stub loading, achieving dual-band operation, broadband matching, and flexible tuning of radiating nulls through structural innovation. See also... Figures 1 to 5 As shown, it includes a first dielectric substrate 9, a second dielectric substrate 6, a third dielectric substrate 2, a ground plane 1, a rectangular open-circuit stub 3, an arc-shaped T-shaped open-circuit stub 5, a coaxial probe 4, a driving circular patch 7, an annular groove 8, and a parasitic circular patch 10. The first dielectric substrate 9 is stacked on top of the second dielectric substrate 6, and the second dielectric substrate 6 is stacked on top of the third dielectric substrate 2. The parasitic circular patch 10 is disposed on the upper surface of the first dielectric substrate 9. The driving circular patch 7 is disposed on the upper surface of the second dielectric substrate 6, and an annular groove 8 with the same center as the driving circular patch 7 is formed on the driving circular patch 7. The rectangular open-circuit stub 3 and the arc-shaped T-shaped open-circuit stub 5 are disposed on the upper surface of the third dielectric substrate 2. The rectangular open-circuit stub 3 is connected to the vertical side of the arc-shaped T-shaped open-circuit stub 5. The ground plane 1 is disposed on the lower surface of the third dielectric substrate 2. The coaxial probe 4 passes through the ground plane 1, the third dielectric substrate 2, and the second dielectric substrate 6 in sequence and is connected to the driving circular patch 7.

[0032] Preferably, the driving circular patch 7 and the parasitic circular patch 10 are located on the same central axis.

[0033] In this embodiment, a third and fourth resonant point are generated by slotting the driving circular patch 7, and a fifth radiation null point is also generated. A second and fourth radiation null point are generated by loading an arc-shaped T-shaped open-circuit stub 5, the length of which is three-quarters of the wavelength corresponding to the second radiation null point frequency, and the length of which is five-quarters of the wavelength corresponding to the fourth radiation null point frequency. A third radiation null point is generated by loading a parasitic circular patch 10, and a first resonant point is also generated. A first radiation null point is generated by loading a rectangular open-circuit stub 3, the length of which is one-quarter of the wavelength corresponding to the first radiation null point frequency. Ultimately, this antenna achieves dual-band omnidirectional filtering characteristics and good broadband characteristics.

[0034] Preferably, the dielectric substrates 9, 6, and 2 are Rogers 4350B, with a dielectric constant of 3.66 and a loss tangent of 0.0037.

[0035] Preferably, the rectangular open branch 3, the arc-shaped T-shaped open branch 5, the driving circular patch 7, the parasitic circular patch 10, and the ground 1 are made of copper.

[0036] Preferably, the ground surface 1 covers the entire lower surface of the third dielectric substrate 2.

[0037] See Figure 6 The figure shows the S-parameter simulation curves of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading described in this embodiment. As can be seen from the figure, the antenna's |S... 11 The |<-10dB bandwidths are 9.1% (3.36-3.68GHz) and 15.6% (5.13-6GHz), respectively, and are applied to the 3.5GHz WiMAX band (3.4-3.6GHz) and the 5GHz WLAN band (5.15-5.825GHz).

[0038] See Figure 7 The figure shows the gain simulation curve of the dual-frequency omnidirectional filter antenna with multiple radiation nulls based on open-stub loading in this embodiment. As can be seen from the figure, the peak gain in the passband reaches 4.3 dBi (low frequency) and 5.6 dBi (high frequency). Five radiation nulls are introduced at 2.825, 3.775, 4.975, 6.15 and 6.7 GHz on the gain curve.

[0039] See Figure 8 and Figure 9The figure shows the E-plane and H-plane radiation patterns of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in this embodiment at 3.5 GHz. As can be seen from the figure, the antenna has good omnidirectional radiation characteristics at this frequency, and the cross-polarization ratio is greater than 47 dB.

[0040] See Figure 10 and Figure 11 The figure shows the E-plane and H-plane radiation patterns of the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading in this embodiment at 5.5 GHz. As can be seen from the figure, the antenna has good omnidirectional radiation characteristics at this frequency and the cross-polarization ratio is greater than 35 dB.

[0041] In summary, this invention generates a third resonant point, a fourth resonant point, and a fifth radiation null point by etching an annular groove on a driving circular patch; it introduces a second and fourth radiation null point by loading an arc-shaped T-shaped open-circuit stub, simultaneously generating a second and a fifth resonant point, with the length of the arc-shaped T-shaped open-circuit stub being three-quarters of the wavelength corresponding to the frequency of the second radiation null point and five-quarters of the wavelength corresponding to the frequency of the fourth radiation null point; it generates a third radiation null point and a first resonant point by coupling a parasitic circular patch with the driving patch; and it introduces a first radiation null point by using a rectangular open-circuit stub, the length of which is one-quarter of the wavelength of the corresponding frequency. Ultimately, dual-band omnidirectional radiation characteristics are achieved, with |S11|<-10dB bandwidths reaching 3.36-3.68GHz (9.1%) and 5.13-6GHz (15.6%), respectively. The peak gain within the passband is 4.3dBi (low frequency) and 5.6dBi (high frequency), and five controllable radiation nulls are formed at 2.825GHz, 3.775GHz, 4.975GHz, 6.15GHz and 6.7GHz. The cross-polarization ratio is greater than 47dB (low frequency) and 35dB (high frequency), meeting the requirements of WiMAX / WLAN dual-band communication.

[0042] Example 2

[0043] This embodiment discloses a wireless communication device, including the multi-radiation null dual-frequency omnidirectional filter antenna based on open-stub loading as described in Embodiment 1.

[0044] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading, characterized in that, The antenna includes a first dielectric substrate (9), a second dielectric substrate (6), a third dielectric substrate (2), a ground plane (1), a rectangular open-circuit stub (3), an arc-shaped T-shaped open-circuit stub (5), a coaxial probe (4), a driving circular patch (7), an annular groove (8), and a parasitic circular patch (10); the first dielectric substrate (9) is stacked on top of the second dielectric substrate (6), the second dielectric substrate (6) is stacked on top of the third dielectric substrate (2), the parasitic circular patch (10) is disposed on the upper surface of the first dielectric substrate (9), and the driving circular patch (7) is disposed on the upper surface of the third dielectric substrate (2). The drive circular patch (7) is provided on the upper surface of the second dielectric substrate (6) and has an annular groove (8) with the same center as it. The rectangular open-circuit stub (3) and the arc-shaped T-shaped open-circuit stub (5) are provided on the upper surface of the third dielectric substrate (2). The rectangular open-circuit stub (3) is connected to the vertical side of the arc-shaped T-shaped open-circuit stub (5). The ground plane (1) is provided on the lower surface of the third dielectric substrate (2). The coaxial probe (4) passes through the ground plane (1), the third dielectric substrate (2), and the second dielectric substrate (6) in sequence and is connected to the drive circular patch (7). The rectangular open-circuit stub (3) generates the first radiation null point. The length of the rectangular open-circuit stub (3) is one-quarter of the wavelength corresponding to the frequency of the first radiation null point. By controlling the length of the rectangular open-circuit stub (3), the left and right movement of the first radiation null point can be controlled. The arc-shaped T-shaped open stub (5) generates a second radiation zero point and a fourth radiation zero point. The length of the arc-shaped T-shaped open stub (5) is three-quarters of the wavelength corresponding to the frequency of the second radiation zero point, and the length of the arc-shaped T-shaped open stub (5) is five-quarters of the wavelength corresponding to the frequency of the fourth radiation zero point. At the same time, a second resonance point and a fifth resonance point are generated. By controlling the length of the arc-shaped T-shaped open stub (5), the left and right movement of the second radiation zero point and the fourth radiation zero point can be controlled.

2. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 1, characterized in that, The driving circular patch (7) and the parasitic circular patch (10) are located on the same central axis.

3. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 1, characterized in that, The antenna has five radiation nulls from low frequency to high frequency, which are the first radiation null, the second radiation null, the third radiation null, the fourth radiation null, and the fifth radiation null in order of frequency from low to high. The antenna has two resonant points in the low frequency band and three resonant points in the high frequency band, which are the first resonant point, the second resonant point, the third resonant point, the fourth resonant point, and the fifth resonant point in order of frequency from low to high.

4. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 3, characterized in that, The mutual coupling between the parasitic circular patch (10) and the driving circular patch (7) generates a third radiation zero point and a first resonance point. The left and right movement of the third radiation zero point can be controlled by controlling the size of the parasitic circular patch (10) and the driving circular patch (7).

5. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 3, characterized in that, The fifth radiation zero point is generated by etching the annular groove (8) on the driving circular patch (7), and the third and fourth resonant points are generated at the same time. The left and right movement of the fifth radiation zero point can be controlled by controlling the position of the annular groove (8).

6. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 1, characterized in that, The rectangular open branch (3), the arc-shaped T-shaped open branch (5), the driving circular patch (7), the parasitic circular patch (10), and the ground (1) are made of copper.

7. The multi-radiation null dual-frequency omnidirectional filtering antenna based on open-circuit stub loading according to claim 1, characterized in that, The ground (1) covers the entire lower surface of the third dielectric substrate (2).

8. A wireless communication device, characterized in that, Includes the multi-radiation null dual-frequency omnidirectional filter antenna based on open-circuit stub loading as described in any one of claims 1-7.

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