An antenna assembly

Abstract

This invention relates to an antenna assembly. The antenna assembly includes a printed feed structure and a waveguide conversion structure, which are connected via a pressure bonding and reflow soldering process. The printed feed structure includes a dielectric substrate, a microstrip signal line, an outer shielding ground layer on the upper surface and a central rectangular coupling window, a shielding metal layer on the lower surface, and metallized vias located around the microstrip signal line, connecting the upper and lower shielding ground layers. The waveguide conversion structure includes a rectangular opening radiating waveguide, a rectangular waveguide channel, a conversion matching waveguide ridge, and a rectangular opening shielding slot. The advantages of this invention are: through the ingeniously designed waveguide conversion structure combined with the printed feed structure, efficient conversion of broadband microwave signals from planar printed circuits to free space is achieved, which helps increase the operating bandwidth and radiation efficiency of traditional microstrip antennas while maintaining advantages such as low profile and easy integration.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically to an antenna assembly. Background Technology

[0002] Antennas are key components of electronic systems such as radar and communication systems. Microstrip antennas, as a type of transceiver antenna, are widely used due to their simple structure, ease of fabrication, and ease of integration. However, microstrip antennas have drawbacks such as narrow bandwidth and poor electromagnetic compatibility. Conventional designs often have an operating bandwidth of less than 25% (gain less than 6dB). Even with special designs such as multilayer structures and slotting, the operating bandwidth is still less than 35% (gain less than 6dB), and maximum gain is usually sacrificed, which cannot meet the development requirements of high-performance radar and communication systems. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an antenna assembly that can solve the problems of narrow operating bandwidth, low maximum gain, and inability to meet the development needs of high-performance radar and communication systems in the prior art.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is: an antenna assembly, characterized in that: it includes a printed feed structure and a waveguide conversion structure, wherein the waveguide conversion structure is disposed above the printed feed structure, and the printed feed structure and the waveguide conversion structure are connected by pressure bonding or reflow soldering; The printed power supply structure includes a dielectric substrate, a microstrip signal line, an upper surface peripheral shielding ground layer, a rectangular coupling window, and a lower surface shielding metal layer. The upper surface peripheral shielding ground layer and the lower surface shielding metal layer are printed on the upper and lower surfaces of the dielectric substrate, respectively. The rectangular coupling window is located at the center of the upper surface peripheral shielding ground layer. The rectangular coupling window has a T-shaped structure, and the smaller end of the rectangular coupling window is connected to the outside of the dielectric substrate. The microstrip signal line is located at the center of the rectangular coupling window along the length of the central rectangular coupling window. The dielectric substrate is provided with a plurality of metallized vias that connect the outer shielding ground layer on the upper surface and the shielding metal layer on the lower surface. The plurality of metallized vias are located around the microstrip signal line and are arranged corresponding to the outer edge of the rectangular coupling window. The waveguide conversion structure includes a rectangular opening radiating waveguide, a rectangular waveguide channel, a conversion matching waveguide ridge, and a rectangular opening shielding slot. The waveguide conversion structure is directly used as an antenna for radiation, and the cross-section of the rectangular opening radiating waveguide is the standard waveguide size.

[0005] Furthermore, the rectangular waveguide channel is located inside the rectangular open radiating waveguide, and a rectangular open shielding groove communicating with the rectangular waveguide channel is provided on one side of the bottom of the rectangular open radiating waveguide. The conversion matching waveguide ridge is half the wavelength of the lowest operating frequency. The rectangular opening shielding slot and the printed feed structure below together form a quasi-coaxial transmission line. The conversion matching waveguide ridge enables the vertical transition of TEM mode signals between the planar printed circuit and the three-dimensional waveguide conversion structure.

[0006] Furthermore, the conversion matching waveguide ridge is located inside the rectangular waveguide channel, and the conversion matching waveguide ridge is located at the center of the inner wide side of the rectangular open radiating waveguide. The rectangular open shielding groove is located below the center of the wide side of the rectangular open radiating waveguide and is located on the side where the microstrip signal line enters the waveguide conversion structure. At the same time, the connection between the conversion matching waveguide ridge and the rectangular open radiating waveguide is located directly above the rectangular open shielding groove.

[0007] Furthermore, one end of the conversion matching waveguide ridge is directly connected to the wide side of the rectangular opening radiating waveguide where the rectangular opening shielding slot is located, and the other end is left with a gap of 0.1mm between it and the other wide side of the rectangular opening radiating waveguide. The other end of the conversion matching waveguide ridge is directly connected to the microstrip signal line. Reflow soldering can be used to achieve the electrical / mechanical dual connection between the printed feed structure and the waveguide conversion structure. The impedance of the microstrip signal line is 50 ohms.

[0008] Furthermore, the size of the end of the conversion matching waveguide ridge connected to the rectangular opening radiating waveguide is larger than the size of the end connected to the microstrip signal line, the middle section between the two ends is gradually transitioned and has an arc-shaped structure, and the thickness of the conversion matching waveguide ridge is smaller than the width of the rectangular opening shielding groove.

[0009] Furthermore, the dielectric substrate has two rows of metallized through holes at the outer edge of the larger end of the rectangular coupling window; the size of the rectangular coupling window matches the size of the rectangular waveguide channel and the rectangular opening shielding groove.

[0010] Furthermore, the distance between the side of the microstrip signal line near the radar chip and the outer shielding layer of the upper surface is 0.1-0.15mm, and the distance between the end of the microstrip signal line connected to the conversion matching waveguide ridge and the outer shielding layer of the upper surface is 0.1-0.15mm.

[0011] The advantages of this invention are: by combining the waveguide conversion structure and the printed feed structure, the broadband microwave signal is efficiently converted from the planar printed circuit to free space. The waveguide conversion structure is directly used as the antenna radiation, which is beneficial to increase the operating bandwidth, high gain and radiation efficiency of traditional microstrip antennas, while maintaining the advantages of low profile, quasi-planar shape and easy integration. It is suitable for microwave and millimeter wave communication / radar antennas. Attached Figure Description

[0012] Figure 1This is a schematic diagram of the disassembled state of an antenna assembly according to the present invention; Figure 2 This is a schematic diagram of the combined state of an antenna assembly according to the present invention; Figure 3 This is an exploded view of the structure of an antenna assembly according to the present invention; Figure 4 This is a comparison chart of the standing wave ratios of an antenna assembly of the present invention and a traditional microstrip patch antenna; Figure 5 This is a comparison diagram of the maximum gain coefficients of an antenna assembly of the present invention and a traditional microstrip patch antenna; Figure 6 This is a typical gain pattern of an antenna assembly according to the present invention; Figure 7 This is a schematic diagram of a traditional microstrip patch antenna. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments will enable those skilled in the art to more fully understand this invention, but do not limit the invention to the scope of these embodiments.

[0014] Please see the appendix Figure 1 and attached Figure 2 This specific embodiment provides an antenna assembly, including a printed feed structure 1 and a waveguide conversion structure 2. The waveguide conversion structure 2 is disposed above the printed feed structure 1, and the printed feed structure 1 and the waveguide conversion structure 2 are electrically / mechanically connected by pressure welding or reflow soldering.

[0015] Please refer to the appendix for further details. Figure 3 The printed feed structure 1 includes a dielectric substrate 15, a microstrip signal line 13, an upper surface peripheral shielding ground layer 11, a rectangular coupling window 12, and a lower surface shielding metal layer 16. The upper surface peripheral shielding ground layer 11 and the lower surface shielding metal layer 16 are printed on the upper and lower surfaces of the dielectric substrate 15, respectively. The rectangular coupling window 12 is located at the center of the upper surface peripheral shielding ground layer 11. The rectangular coupling window 12 has a T-shaped structure, and the smaller end of the rectangular coupling window 12 is connected to the outside of the dielectric substrate 15. The microstrip signal line 13 is located at the center of the rectangular coupling window 12 along its length. The distance between the side of the microstrip signal line 13 near the radar chip and the upper surface peripheral shielding ground layer 11 is 0.1-0.15 mm. The distance between the end of the microstrip signal line 13 connected to the conversion matching waveguide ridge 23 and the upper surface peripheral shielding ground layer 11 is 0.1-0.15 mm.

[0016] The impedance of the microstrip signal line 13 is 50 ohms. The microstrip signal line 13 usually adopts a Zo=SQRT(Zm*Zin)≥50 ohm impedance line structure. Together with the rectangular open shielding slot 24, it forms a quasi-coaxial transmission line, which can effectively prevent energy leakage and reduce transmission loss and electromagnetic coupling effect.

[0017] The dielectric substrate 15 is provided with a plurality of metallized vias 14 that connect the outer shielding ground layer 11 on the upper surface and the shielding metal layer 16 on the lower surface. The plurality of metallized vias 14 are disposed around the microstrip signal line 13 and are arranged corresponding to the outer edge of the rectangular coupling window 12. In this embodiment, two rows of metallized vias 14 are provided on the dielectric substrate 15 at the outer edge position corresponding to the larger end of the rectangular coupling window 12.

[0018] The waveguide conversion structure 2 includes a rectangular open radiating waveguide 21, a rectangular waveguide channel 22, a conversion matching waveguide ridge 23, and a rectangular open shielding slot 24. The waveguide conversion structure 2 is directly used as an antenna for radiation. The rectangular open radiating waveguide 21 has a cross-section of standard waveguide size and uses air as the transmission medium, which has the advantages of low dielectric loss and low dispersion.

[0019] The rectangular waveguide channel 22 is located inside the rectangular open radiating waveguide 21. A rectangular open shielding groove 24 communicating with the rectangular waveguide channel 22 is provided on one side of the bottom of the rectangular open radiating waveguide 21. The size of the rectangular coupling window 12 is preferably matched with the size of the rectangular waveguide channel 22 and the rectangular open shielding groove 24.

[0020] One end of the microstrip signal line 13 is connected to the chip, and the other end is connected to the conversion matching waveguide ridge 23. The size of the conversion matching waveguide ridge 23 is half the wavelength of the lowest operating frequency. The conversion matching waveguide ridge 23 is located inside the rectangular waveguide channel 22 and is located at the center of the inner wide side of the rectangular open radiating waveguide 21. The rectangular open shielding groove 24 is located below the center of the wide side of the rectangular open radiating waveguide 21 and is located on the side where the microstrip signal line 13 enters the waveguide conversion structure 2. At the same time, the connection between the conversion matching waveguide ridge 23 and the rectangular open radiating waveguide 21 is located directly above the rectangular open shielding groove 24.

[0021] The size of the end of the conversion matching waveguide ridge 23 connected to the rectangular open radiating waveguide 21 is larger than the size of the end connected to the microstrip signal line 13. The middle section between the two ends gradually transitions and has an arc-shaped structure. The thickness of the conversion matching waveguide ridge 23 is smaller than the width of the rectangular open shielding groove 24.

[0022] One end of the conversion matching waveguide ridge 23 is directly connected to the wide side of one side of the rectangular opening radiation waveguide 21 where the rectangular opening shielding slot 24 is located, and the other end is left with a gap of 0.1mm between it and the other side of the rectangular opening radiation waveguide 21. The other end of the conversion matching waveguide ridge 23 is directly connected to the microstrip signal line 13.

[0023] The rectangular opening shielding slot 24 and the printed feed structure 1 below together form a quasi-coaxial transmission line, and the vertical transition of the TEM mode signal between the planar printed circuit and the three-dimensional waveguide conversion structure 2 is realized by the conversion matching waveguide ridge 23.

[0024] This embodiment achieves efficient conversion of broadband microwave signals from planar printed circuits to free space by combining waveguide conversion structure 2 and printed feed structure 1. Waveguide conversion structure 2 is directly used as antenna radiation, which is beneficial to increase the operating bandwidth, high gain and radiation efficiency of traditional microstrip antennas, while maintaining the advantages of low profile, quasi-planar shape and easy integration, and is suitable for microwave millimeter wave communication / radar antennas.

[0025] To demonstrate the improvement in radiation bandwidth and gain performance of the technical solution in this embodiment, simulation analysis was performed to obtain the transmission coefficient VSWR diagram, gain curve diagram, and typical gain radiation pattern of the technical solution structure in this embodiment. The results are as follows: Figure 4 , Figure 5 and Figure 6 As shown.

[0026] The antenna provided by the technical solution of this embodiment has good radiation characteristics in the 65-100GHz broadband frequency range, achieving a relative operating bandwidth of 42% with a gain greater than 6dB. This is significantly better than the 22% operating bandwidth of traditional patch antennas with a gain greater than 6dB, and the maximum gain is also improved. This effectively solves the problem of the narrow bandwidth of existing microstrip patch antennas (a schematic diagram of the traditional microstrip patch antenna 3 is shown below). Figure 7 As shown in the figure, it also retains the advantages of microstrip patch antennas, such as simple structure, easy assembly and integration, low profile and high radiation pattern quality.

[0027] The foregoing has shown and described the basic principles and main features of the present invention, as well as its advantages. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An antenna assembly, characterized in that: It includes a printed feed structure and a waveguide conversion structure, wherein the waveguide conversion structure is disposed above the printed feed structure, and the printed feed structure and the waveguide conversion structure are connected by pressure bonding or reflow soldering. The printed power supply structure includes a dielectric substrate, a microstrip signal line, an upper surface peripheral shielding ground layer, a rectangular coupling window, and a lower surface shielding metal layer. The upper surface peripheral shielding ground layer and the lower surface shielding metal layer are printed on the upper and lower surfaces of the dielectric substrate, respectively. The rectangular coupling window is located at the center of the upper surface peripheral shielding ground layer. The rectangular coupling window has a T-shaped structure, and the smaller end of the rectangular coupling window is connected to the outside of the dielectric substrate. The microstrip signal line is located at the center of the rectangular coupling window along the length of the central rectangular coupling window. The dielectric substrate is provided with a plurality of metallized vias that connect the outer shielding ground layer on the upper surface and the shielding metal layer on the lower surface. The plurality of metallized vias are located around the microstrip signal line and are arranged corresponding to the outer edge of the rectangular coupling window. The waveguide conversion structure includes a rectangular opening radiating waveguide, a rectangular waveguide channel, a conversion matching waveguide ridge, and a rectangular opening shielding slot. The waveguide conversion structure is directly used as an antenna for radiation.

2. An antenna assembly according to claim 1, characterized in that: The rectangular waveguide channel is located inside the rectangular open radiating waveguide, and a rectangular open shielding groove communicating with the rectangular waveguide channel is provided on one side of the bottom of the rectangular open radiating waveguide. The conversion matching waveguide ridge is half the wavelength of the lowest operating frequency. The rectangular opening shielding slot and the printed feed structure below together form a quasi-coaxial transmission line. The conversion matching waveguide ridge enables the vertical transition of TEM mode signals between the planar printed circuit and the three-dimensional waveguide conversion structure.

3. An antenna assembly according to claim 1, characterized in that: The conversion matching waveguide ridge is located inside the rectangular waveguide channel and at the center of the inner wide side of the rectangular open radiating waveguide. The rectangular open shielding groove is located below the center of the wide side of the rectangular open radiating waveguide and on the side where the microstrip signal line enters the waveguide conversion structure. At the same time, the connection between the conversion matching waveguide ridge and the rectangular open radiating waveguide is located directly above the rectangular open shielding groove.

4. An antenna assembly according to claim 3, characterized in that: One end of the conversion matching waveguide ridge is directly connected to the wide side of the rectangular opening radiating waveguide where the rectangular opening shielding slot is located, and the other end is separated from the wide side of the rectangular opening radiating waveguide by a gap of 0.1mm. The other end of the conversion matching waveguide ridge is directly connected to the microstrip signal line.

5. An antenna assembly according to claim 4, characterized in that: The size of the end of the conversion matching waveguide ridge connected to the rectangular opening radiating waveguide is larger than the size of the end connected to the microstrip signal line. The middle section between the two ends has a gradual transition and is an arc-shaped structure. The thickness of the conversion matching waveguide ridge is smaller than the width of the rectangular opening shielding groove.

6. An antenna assembly according to claim 1, characterized in that: The dielectric substrate has two rows of metallized through holes at the outer edge of the larger end of the rectangular coupling window; the size of the rectangular coupling window matches the size of the rectangular waveguide channel and the rectangular opening shielding groove.

7. An antenna assembly according to claim 1, characterized in that: The distance between the side of the microstrip signal line near the radar chip and the outer shielding layer of the upper surface is 0.1-0.15mm, and the distance between the end of the microstrip signal line connected to the conversion matching waveguide ridge and the outer shielding layer of the upper surface is 0.1-0.15mm.

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