CN114336023A - Broadband High Gain Substrate Integrated Waveguide Resonator Antenna - Google Patents

Abstract

The invention discloses a broadband high-gain substrate integrated waveguide resonant cavity antenna, which comprises an upper dielectric plate and a lower dielectric plate, wherein the top of the upper dielectric plate is provided with 16 metal patch units distributed diagonally, the top of the lower dielectric plate is provided with a metal floor, the center of the metal floor is etched with a long strip-shaped gap with symmetrical branches, the bottom of the lower dielectric plate is provided with a microstrip feed line, and the terminal of the microstrip feed line is connected with a 50 omega SMA joint. The gain of the traditional slot antenna is improved, the front-to-back ratio of the antenna is reduced, and the radiation performance is improved.

Description

Broadband High Gain Substrate Integrated Waveguide Resonator Antenna

technical field

The invention belongs to the technical field of waveguide antennas, and relates to a broadband high-gain substrate integrated waveguide resonant cavity antenna.

Background technique

As the terminal of the communication system, the antenna affects the performance of the entire communication system, and the detection distance represents the performance of the antenna. If the detection distance and detection accuracy are expressed by the parameters of the antenna, it is mainly reflected in the level of the antenna gain. The higher the gain of the antenna, the longer the detection distance. However, as the gain of the antenna increases, the back radiation of the antenna will inevitably increase, which will affect the radiation performance of the antenna. The small front-to-back ratio presents researchers with a lot of challenges.

The emergence of substrate-integrated waveguide (SIW) meets people's needs for high-directional antennas. This form of antenna has a simple structure, high Q value and directivity, and is easy to integrate with the system. At the same time, as a newly emerging technology in recent years, metasurfaces have attracted the attention of many researchers. Loading metasurfaces into the antenna system can effectively improve the overall performance of the antenna. For example, widening the bandwidth, beam steering, polarization conversion, increasing gain and so on. Combining the SIW antenna with the metasurface fully retains the advantages of high directivity and low back radiation of the SIW antenna, and greatly improves the overall performance of the antenna with the help of the metasurface. Therefore, the integration of these two technologies is very important. It is promising and has attracted the attention of many researchers.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a broadband high-gain substrate integrated waveguide resonant cavity antenna, which improves the gain of the traditional slot antenna, reduces the front-to-back ratio of the antenna, and improves the radiation performance.

The technical scheme adopted in the present invention is that the broadband high-gain substrate integrated waveguide resonant cavity antenna includes an upper dielectric plate and a lower dielectric plate, 16 diagonally distributed metal patch units are arranged on the top of the upper dielectric plate, and the lower dielectric plate A metal floor is arranged at the top of the metal floor, and a long slit with symmetrical branches is etched in the center of the metal floor. A microstrip feeder is arranged at the bottom of the lower dielectric plate, and the feeder terminal of the microstrip feeder is connected to a 50Ω SMA connector.

The feature of the present invention also lies in:

There are two short branches symmetrically loaded near the radiation zero point of the gap.

The 16 metal elements are distributed diagonally with the same axial distance.

A SIW resonant cavity is distributed around the metal patch unit, and the metal through hole of the SIW resonant cavity is connected to the metal floor.

The upper dielectric board and the lower dielectric board use Rogers 4003C dielectric boards with a dielectric constant of 3.38.

The beneficial effects of the invention are: the broadband high-gain substrate integrated waveguide resonant cavity antenna of the invention improves the gain of the traditional slot antenna, reduces the front-to-back ratio of the antenna, and improves the radiation performance. The multi-mode resonance theory is introduced to widen the bandwidth of the antenna. The metasurface is located on the top of the radiating antenna, which is used to further improve the overall performance of the antenna. At the same time, the traditional slot antenna has relatively large backward radiation and more energy loss. The present invention adopts SIW resonance. The cavity design further improves the front-to-back ratio of the antenna. The most important and innovative point of the present invention is that through the improved design of the metasurface unit, the gain of the antenna is increased by about 2dBi.

Description of drawings

1 is a schematic structural diagram of a broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention;

Fig. 2 is the evolution comparison diagram of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention;

3 is a comparison diagram of the S parameter of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention as a function of frequency;

4 is a comparison diagram of the gain of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention varying with frequency;

5 is a comparison diagram of the gain pattern of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention changing with frequency at 5 GHz;

6 is a schematic diagram of the S-parameter learning of the slot in the broadband high-gain substrate integrated waveguide resonator antenna of the present invention;

7 is a schematic diagram of the learning of the pattern parameters when the slot in the broadband high-gain substrate integrated waveguide resonator antenna of the present invention is at 5 GHz;

Fig. 8 is the simulation and actual measurement S parameter variation curve with frequency of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention;

FIG. 9 is the simulation and measured gain versus frequency curve of the broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention, as shown in FIG. 1 , includes an upper dielectric plate and a lower dielectric plate. The top of the upper dielectric plate is provided with 16 diagonally distributed metal patch units, and the The top is provided with a metal floor, the center of the metal floor is etched with long slits with symmetrical branches, the bottom of the lower dielectric plate is provided with a microstrip feeder, and the terminal of the microstrip feeder is connected to a 50Ω SMA connector. There are two short branches symmetrically loaded near the radiation zero point of the gap. The 16 metal elements are distributed diagonally with the same axial distance. A SIW resonant cavity is distributed around the metal patch unit, and the metal through hole of the SIW resonant cavity is connected to the metal floor. The upper dielectric board and the lower dielectric board use Rogers 4003C dielectric boards with a dielectric constant of 3.38.

The broadband high-gain substrate integrated waveguide resonant cavity antenna of the invention is composed of two layers of dielectric plates and three layers of metal surfaces. 16 diagonally distributed metal patch units are placed on the top of the upper layer of dielectric plates, and 16 diagonally distributed metal patch units are placed on the top of the lower layer of dielectric plates. Metal floor, the center of the metal floor is etched with long slits with symmetrical branches, and the bottom of the lower dielectric board is provided with a microstrip feed line, and the terminal of the feed line is connected to a 50Ω SMA connector. The antenna is fed by a multi-mode slot antenna, and two short branches and symmetry are added near the radiation zero point of the slot, which introduces additional radiation modes and effectively widens the working bandwidth of the antenna.

The broadband high-gain substrate integrated waveguide resonant cavity antenna of the invention adopts two Rogers 4003C dielectric plates with a dielectric constant of 3.38, the thicknesses are respectively H ₁ and H ₂ , the dimensions of the dielectric plates are L ₁ ×L ₁ , and there are 16 dielectric plates. The diagonally distributed metal patch unit is located on the top surface of the upper dielectric plate, the SIW resonant cavity is distributed around the metal unit, the diameter D _siw , the metal through holes with a distance of P _siw connect the patch and the floor, and the metal floor is located on the top surface of the lower dielectric plate , there is no gap between the two dielectric plates. A long slot with symmetrical branches is etched in the center of the metal floor, and a microstrip feed line is arranged at the bottom of the lower dielectric plate. The broadband high-gain substrate integrated waveguide resonant cavity antenna of the invention adopts side feeding, has one feeding port in total, and the terminal of the feeding line is connected with a 50Ω SMA connector.

The broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention introduces the multi-mode resonance theory in the feeding part to widen the bandwidth of the antenna. Secondly, a metasurface is loaded on the top of the radiating antenna to further improve the overall performance of the antenna. At the same time, the traditional slot antenna has relatively large backward radiation and large energy loss. The broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention adopts SIW The design of the resonant cavity further improves the front-to-back ratio of the antenna. The broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention improves the gain of the antenna by improving the design of the metasurface unit, and the improvement range is about 2dBi.

Figure 2 shows the evolution diagram design of the antenna. The antenna is composed of two layers of dielectric plates, fed by a multimode slot antenna, and the metasurface is composed of 4×4 corner-cut patch units located on top of the upper layer of the dielectric plate. On the basis of the antenna, an SIW resonant cavity is introduced on the periphery of the metasurface to form the antenna 2. From Figure 3 and Figure 4, it can be seen that the impedance bandwidth of Antenna 2 and Antenna 1 has a small broadening (200MHz) in the low frequency part, and the gain is also not greatly improved (about 0.4dBi), which shows that the SIW resonant cavity is suitable for the original antenna. The performance will not cause great deterioration, and Figure 5 shows that the SIW resonator can effectively reduce the back radiation and improve the front-to-back ratio of the antenna. Here, because the SIW resonator effectively binds the energy of the metasurface, reducing the energy The loss of the antenna increases the gain of the antenna to a certain extent. At the same time, due to the radiation characteristics of the SIW resonator itself, the backward radiation is reduced, thereby improving the overall front-to-back ratio of the antenna. Figures 6 and 7 are for parameter learning of the distance G between the superstructures. As shown in Figure 6, as G increases, the working bandwidth becomes narrower, but the matching performance becomes better at the same time. By selecting an appropriate G value, it can be adjusted. working bandwidth. As shown in Fig. 7, with the increase of G, the side lobes decrease, and the backward radiation is basically unchanged.

Figure 8 shows the simulated and measured graph of S-parameters varying with frequency. It can be seen from Figure 8 that the simulated operating bandwidths of the antennas are 1.7GHz (4.3GHz-6GHz) respectively, and the measured bandwidths are slightly narrower than the simulated ones, respectively. The small difference between the measured bandwidth and the simulated bandwidth of 1.6GHz (4.1GHz-5.6GHz) may be caused by the influence of solder joints and processing errors. Figure 9 shows the simulated and measured graph of the change of gain with frequency. It can be seen from the figure that the simulated gain is relatively stable within the operating frequency band. At 5.4GHz, the peak gain is 10.9dBi, and the measured gain is similar to the simulated gain.

The broadband high-gain substrate integrated waveguide resonant cavity antenna of the invention includes two layers of dielectric plates and three layers of metal surfaces, 16 diagonally distributed metal patch units are placed on the top of the upper layer dielectric plate, and metal patch units are placed on the top of the lower layer dielectric plate. The floor, the center of the metal floor is etched with a long slit with symmetrical branches, the bottom of the lower dielectric board is provided with a microstrip feed line, and the terminal of the feed line is connected to a 50Ω SMA connector. The multi-mode resonance theory is introduced to widen the bandwidth of the antenna, and the metasurface is located on the top of the radiating antenna, which is used to further improve the overall performance of the antenna. The front-to-back ratio of the antenna. The broadband high-gain substrate integrated waveguide resonant cavity antenna of the present invention improves the gain of the antenna by improving the design of the metasurface unit, and the improvement range is about 2dBi. The gain of the traditional slot antenna is improved, the front-to-back ratio of the antenna is reduced, and the radiation performance is improved.

Claims (5)

1. Broadband high-gain substrate integrated waveguide resonant cavity antenna, characterized in that it comprises an upper-layer dielectric plate and a lower-layer dielectric plate, and the top of the upper-layer dielectric plate is provided with 16 diagonally distributed metal patch units, and the lower-layer dielectric The top of the board is provided with a metal floor, the center of the metal floor is etched with long slits with symmetrical branches, the bottom of the lower dielectric board is provided with a microstrip feeder, and the feeder terminal of the microstrip feeder is connected to the end of the feeder. 50Ω SMA connector is connected. 2 . The broadband high-gain substrate-integrated waveguide resonator cavity antenna according to claim 1 , wherein two short branches are symmetrically loaded near the radiation zero point of the slot. 3 . 3 . The broadband high-gain substrate-integrated waveguide resonant cavity antenna according to claim 1 , wherein the 16 metal elements are distributed diagonally and have the same axial distance. 4 . 4 . The broadband high-gain substrate-integrated waveguide resonant cavity antenna according to claim 1 , wherein SIW resonators are distributed around the metal patch unit, and metal through holes of the SIW resonator are connected to the metal floor. 5 . 5. The broadband high-gain substrate-integrated waveguide resonant cavity antenna according to claim 1, wherein the upper dielectric plate and the lower dielectric plate are Rogers 4003C dielectric plates with a dielectric constant of 3.38.

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