Substrate Integrated Waveguide Horn Antenna Array and Wireless Communication Device

Abstract

The present invention discloses a substrate integrated waveguide horn antenna array and a wireless communication device, which includes three layers of dielectric substrates. On the middle layer dielectric substrate, a plurality of identical substrate integrated waveguide H-plane horn antenna units are arranged side by side. In the horn antenna unit, two trapezoidal sections are dug out to form a stepped horn-shaped dielectric. At the positions corresponding to the horn apertures of the upper and lower layers of dielectric substrates, a dipole array and a rectangular patch are arranged. A metal via array and a rectangular patch array are arranged at the rear end of the dipole array. The present invention realizes good broadband characteristics under a low-thickness substrate; realizes the miniaturization of the horn antenna by reducing the longitudinal length of the horn; realizes the correction of the internal electric field distribution of the horn by digging out the stepped horn-shaped dielectric composed of two trapezoidal sections; improves the gain and front-to-back ratio by arranging a metal via array and a rectangular patch at the rear end of the dipole array, and feeds the horn antenna array through the SIW power divider feeding network, finally realizing the performance of miniaturization, broadband and high gain.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and in particular to a substrate integrated waveguide horn antenna array with miniaturization, broadband and high gain, and a wireless communication device. Background Art

[0002] Horn antennas are widely used in fields such as communication systems, radars, imaging, and radio astronomy. Although metal waveguide horn antennas can be used in the above systems, they usually have large volume, heavy weight, high price, and are not easy to integrate with other components and devices in the system. With the increasing integration of circuit systems, the requirement for miniaturization of components is also getting higher and higher. Therefore, the miniaturization technology of antennas has gradually become a hot topic. In addition, the ultra-wideband of the 5G frequency band requires the antenna to achieve broadband performance, and the high loss in the millimeter wave frequency band also poses higher requirements for the gain of the antenna. Summary of the Invention

[0003] The first object of the present invention is to overcome the disadvantages and deficiencies of the prior art, and provide a substrate integrated waveguide horn antenna array with miniaturization, broadband and high gain, which can achieve good broadband characteristics at a low substrate thickness, and when reducing the longitudinal length of the horn by 50%, not only maintaining the gain deterioration of the antenna, but instead improving the gain of the antenna, and finally achieving the performance of miniaturization, broadband and high gain.

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

[0005] The first object of the present invention is achieved by the following technical solutions: A substrate integrated waveguide horn antenna array, including a first dielectric substrate, a second dielectric substrate and a third dielectric substrate. A plurality of identical H-plane horn antenna units of substrate integrated waveguide are arranged side by side on the first dielectric substrate, with the horn openings facing the same direction. Two trapezoidal dielectrics are dug out inside the H-plane horn antenna unit to correct the electric field phase after miniaturization to improve the gain.

[0006] The second dielectric substrate is arranged above the front end of the first dielectric substrate, and a first dipole array is loaded at the position corresponding to the horn antenna aperture on the second dielectric substrate, and a first rectangular patch is arranged on the upper surface to achieve broadband. A first rectangular patch array and a first metal via array are arranged at the rear end of the horn aperture on the upper surface of the second dielectric substrate to improve the gain.

[0007] The third dielectric substrate is arranged below the front end of the first dielectric substrate, and a second dipole array is loaded at the position corresponding to the horn antenna aperture on the third dielectric substrate, and a second rectangular patch is arranged on the lower surface to achieve broadband. A second rectangular patch array and a second metal via array are arranged at the rear end of the horn antenna aperture on the lower surface of the third dielectric substrate to improve the gain.

[0008] The first dielectric substrate, the second dielectric substrate, and the third dielectric substrate all extend a certain distance towards the front end of the horn aperture to improve the gain;

[0009] The first rectangular patch and the second rectangular patch are both symmetric about the dielectric substrate, and the first rectangular patch array and the second rectangular patch array are both symmetric about the dielectric substrate;

[0010] The first dipole array passes through the second dielectric substrate to connect the first rectangular patch and the upper surface of the first dielectric substrate; the second dipole array passes through the third dielectric substrate to connect the second rectangular patch and the lower surface of the first dielectric substrate;

[0011] The first metal via array and the second metal via array are both symmetric about the dielectric substrate; the first metal via array passes through the second dielectric substrate to connect the first rectangular patch array and the upper surface of the first dielectric substrate; the second metal via array passes through the third dielectric substrate to connect the second rectangular patch array and the lower surface of the first dielectric substrate.

[0012] Preferably, an SIW power divider feeding network and feeding probes are provided on the second dielectric substrate. The SIW power divider feeding network and the feeding probes are located at the rear end of multiple H-plane horn antenna units for feeding the multiple H-plane horn antenna units.

[0013] Preferably, both the first rectangular patch array and the second rectangular patch array are composed of two rectangular patches.

[0014] Preferably, both the first dipole array and the second dipole array are arranged near the horn aperture side and are composed of multiple metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate; the first metal via array and the second metal via array are arranged behind the dipole arrays and are both composed of two rows of metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate.

[0015] Preferably, two trapezoidal dielectrics are dug out inside the H-plane horn antenna unit to form a stepped horn-shaped dielectric. Among them, the distance from the small trapezoid of the two dug-out trapezoidal dielectrics to the inner wall of the horn is less than the thickness required to achieve a hard boundary, and the distance from the large trapezoid of the two dug-out trapezoidal dielectrics to the inner wall of the horn is greater than the thickness required to achieve a hard boundary. The trapezoidal inclination angle is the same as the opening angle of the H-plane horn antenna unit and extends inward from the horn aperture of the H-plane horn antenna unit.

[0016] Preferably, the H-plane horn antenna unit includes upper and lower metal layers disposed on the upper and lower surfaces of the first dielectric substrate and metal vias disposed in the first dielectric substrate. The upper and lower metal layers are used to form the wide sides of the substrate integrated waveguide, and the metal vias are respectively connected to the upper and lower metal layers to form the narrow sides of the substrate integrated waveguide. The height of the metal vias is set to the thickness of the first dielectric substrate, the radius of the metal vias ranges from 0.4 to 0.6 mm, and the distance between the centers of adjacent two metal vias ranges from 1.5 to 1.7 mm.

[0017] Preferably, the waveguide width of the SIW power divider feeding network is the same as that of the H-plane horn antenna unit, and symmetric individual metal vias are provided in the SIW power divider feeding network for impedance matching adjustment.

[0018] The second object of the present invention is achieved by the following technical solution: a wireless communication device, including the above-mentioned substrate integrated waveguide horn antenna array.

[0019] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0020] 1. In the present invention, by providing a dipole array and a rectangular patch at the corresponding horn aperture of the upper and lower two-layer dielectric substrates, good broadband characteristics are achieved under a low-thickness substrate; miniaturization of the horn antenna is realized by reducing the longitudinal length of the horn; by removing a stepped horn-shaped dielectric composed of two trapezoids inside the horn antenna unit, the correction of the internal electric field distribution of the horn is realized, overcoming the negative effects brought by miniaturization and improving the gain; by providing a metal via array and a rectangular patch at the rear end of the dipole array, the gain and front-to-back ratio are improved, and finally, the horn antenna array is fed by the SIW power divider feeding network, ultimately realizing the performance of miniaturized broadband and high gain.

[0021] 2. The present invention adopts the loading of rectangular patches and dipole arrays, as well as the loading of metal via arrays and rectangular patch arrays, and also removes a stepped horn-shaped dielectric composed of two trapezoids inside the horn antenna unit. Experiments prove that the |S 11 |-10 dB bandwidth is 31.6%, the gain is stable within the working bandwidth, the maximum gain is 15.55 dBi. Compared with the best gain horn with the same aperture width, the longitudinal length of the antenna is reduced by 50%, and the gain is increased by 3.3 dB, obtaining good miniaturized broadband and high gain characteristics. Description of the Drawings

[0022] Figure 1 It is a perspective view of the substrate integrated waveguide horn antenna array according to an embodiment of the present invention.

[0023] Figure 2 It is a top view of the substrate integrated waveguide horn antenna array according to an embodiment of the present invention.

[0024] Figure 3 It is the bottom view of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention.

[0025] Figure 4 It is the side view of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention.

[0026] Figure 5 It is the E-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 14 GHz.

[0027] Figure 6 It is the H-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 14 GHz.

[0028] Figure 7 It is the E-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 16 GHz.

[0029] Figure 8 It is the H-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 16 GHz.

[0030] Figure 9 It is the E-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 18 GHz.

[0031] Figure 10 It is the H-plane radiation pattern of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention at 18 GHz.

[0032] Figure 11 It is the S-parameter diagram of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention.

[0033] Figure 12 It is the gain curve diagram of the substrate integrated waveguide horn antenna array according to the embodiment of the present invention.

[0034] Wherein, 1 - the second dielectric substrate, 2 - the first dielectric substrate, 3 - the third dielectric substrate, 4 - the first rectangular patch, 5 - the first dipole array, 6 - the first rectangular patch array, 7 - the first metal via array, 8 - the second rectangular patch, 9 - the second dipole array, 10 - the second rectangular patch array, 11 - the second metal via array, 12 - the SIW power divider feeding network, 13 - the feeding probe. Detailed implementation manners

[0035] The present invention will be further described in detail below in conjunction with the embodiments and the drawings, but the implementation manners of the present invention are not limited thereto.

[0036] Embodiment 1

[0037] The substrate integrated waveguide horn antenna processed by PCB technology can overcome the disadvantages of the prior art, and has the advantages of small size, light weight, low cost, and being easy to be integrated into a miniaturized wireless communication platform; a circuit system with a higher integration degree often has higher requirements for the size of the antenna. Therefore, the miniaturization technology of the antenna is quite important in applications. The broadband antenna can utilize the abundant spectrum resources in the millimeter-wave band, operate in a relatively wide frequency band range, meet the communication requirements of the system for multiple different frequency bands, and adapt to different working scenarios. In millimeter-wave communication, due to the higher frequency, the loss of electromagnetic wave radiation is greater. Therefore, the requirement for the antenna gain is better. At this time, a better implementation method is to array high-gain antenna elements. Therefore, this embodiment provides a miniaturized broadband high-gain substrate integrated waveguide horn antenna array.

[0038] See Figures 1 to 4 As shown, this embodiment provides a miniaturized broadband high-gain substrate integrated waveguide horn antenna array, which can be applied to wireless communication devices, including a first dielectric substrate 2, a second dielectric substrate 1, and a third dielectric substrate 3. A plurality of identical H-plane horn antenna elements of substrate integrated waveguides are arranged side by side on the first dielectric substrate 2, and the horn mouths face the same direction. Two trapezoidal dielectrics are dug out inside the H-plane horn antenna element to correct the electric field phase after miniaturization to improve the gain.

[0039] The second dielectric substrate 1 is arranged above the front end of the first dielectric substrate 2, and a first dipole array 5 is loaded at the position corresponding to the horn antenna aperture on the second dielectric substrate 2, and a first rectangular patch 4 is arranged on the upper surface to achieve broadband. A first rectangular patch array 6 and a first metal via array 7 are arranged on the upper surface of the second dielectric substrate 1 at the rear end of the horn aperture to improve the gain.

[0040] The third dielectric substrate 3 is arranged below the front end of the first dielectric substrate 2, and a second dipole array 9 is loaded at the position corresponding to the horn antenna aperture on the third dielectric substrate 3, and a second rectangular patch 8 is arranged on the lower surface to achieve broadband. A second rectangular patch array 10 and a second metal via array 11 are arranged on the lower surface of the third dielectric substrate 3 at the rear end of the horn antenna aperture to improve the gain.

[0041] The first dielectric substrate 2, the second dielectric substrate 1, and the third dielectric substrate 3 all extend a certain distance towards the front end of the horn aperture to improve the gain.

[0042] The first rectangular patch 4 and the second rectangular patch 8 are both symmetric about the dielectric substrate, and the first rectangular patch array 6 and the second rectangular patch array 10 are both symmetric about the dielectric substrate.

[0043] The first dipole array 5 passes through the second dielectric substrate 1 to connect the upper surface of the first rectangular patch 4 and the first dielectric substrate 4; the second dipole array 9 passes through the third dielectric substrate 3 to connect the lower surface of the second rectangular patch 8 and the first dielectric substrate 4.

[0044] Both the first metal via array 7 and the second metal via array 11 are symmetric about the dielectric substrate. The first metal via array 7 passes through the second dielectric substrate 1 to connect the first rectangular patch array 6 and the upper surface of the first dielectric substrate 2; the second metal via 11 array passes through the third dielectric substrate 3 to connect the second rectangular patch array 10 and the lower surface of the first dielectric substrate 2.

[0045] An SIW power divider feeding network 12 and a feeding probe 13 are provided on the second dielectric substrate 1. The SIW power divider feeding network 12 and the feeding probe 13 are located at the rear ends of a plurality of H-plane horn antenna units for feeding the plurality of H-plane horn antenna units.

[0046] Preferably, the lengths of the first rectangular patch 4 and the second rectangular patch 8 are 2 mm and are arranged in front of the horn antenna aperture; the first rectangular patch array 6 and the second rectangular patch array 10 are each composed of two rectangular patches. The length of the rectangular patches is 2.5 mm and they are 1 mm away from the dipole array.

[0047] Preferably, both the first dipole array 5 and the second dipole array 9 are arranged close to the horn aperture side and are composed of 33 metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate.

[0048] The first metal via array 7 and the second metal via array 11 are arranged behind the dipole array and are each composed of two rows of metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate.

[0049] Preferably, two trapezoidal dielectrics are dug out inside the H-plane horn antenna unit to form a stepped horn-shaped dielectric. The distances between the two dug-out trapezoidal dielectrics and the two sides of the horn inner wall are about the thickness required to achieve a hard boundary. Among them, the distance between the small trapezoid of the two dug-out trapezoidal dielectrics and the horn inner wall is slightly less than the thickness required to achieve a hard boundary, and the distance between the large trapezoid of the two dug-out trapezoidal dielectrics and the horn inner wall is slightly greater than the thickness required to achieve a hard boundary. The trapezoidal inclination angle is the same as the opening angle of the H-plane horn antenna unit and extends inward from the horn aperture of the H-plane horn antenna unit.

[0050] Preferably, the H-plane horn antenna unit includes upper and lower metal layers disposed on the upper and lower surfaces of the first dielectric substrate 2 and metal vias disposed in the first dielectric substrate 2. The upper and lower metal layers are used to form the wide sides of the substrate integrated waveguide, and the metal vias are respectively connected to the upper and lower metal layers to form the narrow sides of the substrate integrated waveguide. The height of the metal vias is set to the thickness of the first dielectric substrate 2, the radius of the metal vias ranges from 0.4 to 0.6 mm, and the distance between the centers of adjacent two metal vias ranges from 1.5 to 1.7 mm.

[0051] Preferably, the waveguide width of the SIW power divider feeding network 12 is the same as that of the H-plane horn antenna unit, and some symmetric individual metal vias are provided in the SIW power divider feeding network 12 for impedance matching adjustment.

[0052] Preferably, the height of the feeding probe 13 is 2 mm and the radius is 0.3 mm.

[0053] Preferably, the first dielectric substrate 2, the second dielectric substrate 1, and the third dielectric substrate 3 all adopt Rogers RT4003C, with a dielectric constant of 3.55, a loss tangent of 0.0027, and a thickness of 1.524 mm.

[0054] In this embodiment, by arranging a dipole array and a rectangular patch at the corresponding horn aperture of the upper and lower dielectric substrates, good broadband characteristics are achieved under a low-thickness substrate; miniaturization of the horn antenna is realized by reducing the longitudinal length of the horn; by removing a stepped horn-shaped dielectric composed of two trapezoids inside the horn antenna unit, the correction of the internal electric field distribution of the horn is realized, overcoming the negative impact brought by miniaturization and improving the gain; by arranging a metal via array and a rectangular patch at the rear end of the dipole array, the gain and the front-to-back ratio are improved. Finally, the horn antenna array is fed by the SIW power divider feeding network, and the performance of miniaturized broadband high gain is finally realized.

[0055] Figure 5 and Figure 6 are the E-plane radiation pattern and H-plane radiation pattern of the substrate integrated waveguide horn antenna array of this embodiment at 14 GHz. It can be seen from the figure that the antenna has good directional radiation characteristics at this frequency point, the front-to-back ratio is less than -10 dB, and the cross polarization is less than -40 dB.

[0056] Figure 7 and Figure 8 are the E-plane radiation pattern and H-plane radiation pattern of the substrate integrated waveguide horn antenna array of this embodiment at 16 GHz. It can be seen from the figure that the antenna has good directional radiation characteristics at this frequency point, the front-to-back ratio is less than -10 dB, and the cross polarization is less than -40 dB.

[0057] Figure 9 and Figure 10 are the E-plane radiation pattern and H-plane radiation pattern of the substrate integrated waveguide horn antenna array of this embodiment at 18 GHz. It can be seen from the figure that the antenna has good directional radiation characteristics at this frequency point, the front-to-back ratio is less than -10 dB, and the cross polarization is less than -40 dB.

[0058] Figure 11 is the simulation curve of the S-parameters of the substrate integrated waveguide horn antenna array of this embodiment. It can be seen from the figure that the |S 11 | < -10 dB bandwidth is approximately 13.1 - 18 GHz, 31.6%, and it is applied to the ku band.

[0059] Figure 12 is the simulation curve of the gain of the substrate integrated waveguide horn antenna array of this embodiment. It can be seen from the figure that the maximum gain of the antenna is 15.55 dBi.

[0060] In summary, in the present invention, by setting a dipole array and a rectangular patch at the corresponding horn apertures of the upper and lower dielectric substrates, good broadband characteristics are achieved with a low-thickness substrate; miniaturization of the horn antenna is realized by reducing the longitudinal length of the horn; by removing a stepped horn-shaped dielectric composed of two trapezoids inside the horn antenna unit, the correction of the internal electric field distribution of the horn is realized, overcoming the negative impact brought by miniaturization and improving the gain; by setting a metal via array and a rectangular patch at the rear end of the dipole array, the gain and the front-to-back ratio are improved. Finally, the horn antenna array is fed by the SIW power divider feeding network, and finally an SIW horn antenna array with an impedance matching bandwidth of approximately 31.6%, a maximum gain of approximately 15.55 dBi is realized. Compared with the horn with the best gain of the same aperture width, the longitudinal length of the antenna is reduced by 50%, and the gain is increased by 3.3 dB, realizing a miniaturized broadband high-gain SIW horn antenna array.

[0061] Embodiment 2

[0062] This embodiment provides a wireless communication device, including the substrate integrated waveguide horn antenna array described in Embodiment 1.

[0063] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. Substrate integrated waveguide horn antenna array, characterized in that It includes a first dielectric substrate, a second dielectric substrate, and a third dielectric substrate. On the first dielectric substrate, there are multiple identical substrate integrated waveguide H-plane horn antenna units arranged side by side with the same flared mouth orientation. Two trapezoidal dielectrics are dug out inside the H-plane horn antenna units to correct the electric field phase after miniaturization to improve the gain. The second dielectric substrate is arranged above the front end of the first dielectric substrate. At the position corresponding to the horn antenna aperture on the second dielectric substrate, a first dipole array is loaded and a first rectangular patch is arranged on the upper surface to achieve broadband. On the upper surface of the second dielectric substrate at the rear end of the horn aperture, a first rectangular patch array and a first metal via array are arranged to improve the gain. The third dielectric substrate is arranged below the front end of the first dielectric substrate. At the position corresponding to the horn antenna aperture on the third dielectric substrate, a second dipole array is loaded and a second rectangular patch is arranged on the lower surface to achieve broadband. On the lower surface of the third dielectric substrate at the rear end of the horn antenna aperture, a second rectangular patch array and a second metal via array are arranged to improve the gain. The first dielectric substrate, the second dielectric substrate, and the third dielectric substrate all extend a certain distance towards the front end of the horn aperture to improve the gain. The first rectangular patch and the second rectangular patch are both symmetric about the dielectric substrate. The first rectangular patch array and the second rectangular patch array are both symmetric about the dielectric substrate. The first dipole array passes through the second dielectric substrate to connect the first rectangular patch and the upper surface of the first dielectric substrate. The second dipole array passes through the third dielectric substrate to connect the second rectangular patch and the lower surface of the first dielectric substrate. The first metal via array and the second metal via array are both symmetric about the dielectric substrate. The first metal via array passes through the second dielectric substrate to connect the first rectangular patch array and the upper surface of the first dielectric substrate. The second metal via array passes through the third dielectric substrate to connect the second rectangular patch array and the lower surface of the first dielectric substrate.

2. The substrate integrated waveguide horn antenna array according to claim 1, wherein On the second dielectric substrate, an SIW power divider feeding network and a feeding probe are arranged. The SIW power divider feeding network and the feeding probe are located at the rear end of the multiple H-plane horn antenna units to feed the multiple H-plane horn antenna units.

3. The substrate integrated waveguide horn antenna array according to claim 1, characterized in that, Both the first rectangular patch array and the second rectangular patch array are composed of two rectangular patches.

4. The substrate integrated waveguide horn antenna array according to claim 1, wherein Both the first dipole array and the second dipole array are arranged close to the horn aperture side and are composed of multiple metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate. The first metal via array and the second metal via array are arranged behind the dipole arrays and are both composed of two rows of metal vias. The radius ranges from 0.4 mm to 0.6 mm, and the height of the metal vias is set to the thickness of the corresponding dielectric substrate.

5. The substrate integrated waveguide horn antenna array according to claim 1, characterized in that, Two trapezoidal dielectrics are removed from inside the H-plane horn antenna unit to form a stepped horn-shaped dielectric. Among them, the distance between the small trapezoid of the two removed trapezoidal dielectrics and the inner wall of the horn is less than the thickness required to achieve a hard boundary, and the distance between the large trapezoid of the two removed trapezoidal dielectrics and the inner wall of the horn is greater than the thickness required to achieve a hard boundary. The trapezoidal inclination angle is the same as the opening angle of the H-plane horn antenna unit and extends inward from the horn aperture of the H-plane horn antenna unit.

6. The substrate integrated waveguide horn antenna array according to claim 1, wherein, The H-plane horn antenna unit includes upper and lower metal layers disposed on the upper and lower surfaces of the first dielectric substrate and metal vias disposed in the first dielectric substrate. The upper and lower metal layers are used to form the wide sides of the substrate integrated waveguide, and the metal vias are respectively connected to the upper and lower metal layers to form the narrow sides of the substrate integrated waveguide. The height of the metal vias is set to the thickness of the first dielectric substrate, the radius of the metal vias ranges from 0.4 to 0.6 mm, and the distance between the centers of adjacent two metal vias ranges from 1.5 to 1.7 mm.

7. The substrate integrated waveguide horn antenna array according to claim 2, characterized in that The waveguide width of the SIW power divider feeding network is the waveguide width of the H-plane horn antenna unit, and symmetric individual metal vias are provided in the SIW power divider feeding network for adjusting impedance matching.

8. A wireless communication device, characterized in that, It includes the substrate integrated waveguide horn antenna array according to any one of claims 1-7.

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