CN110391504A - A Microstrip Array Antenna - Google Patents

Abstract

The present invention relates to array antenna technique fields, specifically disclose a kind of micro-strip array antenna, wherein, micro-strip array antenna includes: substrate, power splitter, the uniform front of micro-strip and metal waveguide, the first surface and second surface of substrate have wiring, power splitter includes the first copper foil that first surface is arranged in and the second copper foil that second surface is arranged in, first copper foil and the second copper foil are connected by the through-hole through substrate, the uniform front of micro-strip is arranged at the first surface of substrate and connect with power splitter, metal waveguide is located at power splitter position, and it is arranged through substrate, metal waveguide position is provided with coupling gap on substrate, radio-frequency input signals can be fed into power splitter by coupling gap and metal waveguide, power splitter can generate the radio frequency output signal of constant amplitude according to radio-frequency input signals, and day is formed by the uniform front of micro-strip Line wave beam.Micro-strip array antenna provided by the invention has simple structure, assembly and advantage easy to maintenance.

Description

A Microstrip Array Antenna

technical field

The invention relates to the technical field of array antennas, in particular to a microstrip array antenna.

Background technique

With the development of my country's economy and the continuous improvement of people's living standards, car safety driving has increasingly become the focus of public attention. At the same time, car millimeter-wave radar has attracted more and more attention as an active safety defense measure. As a key component that directly affects the performance of automotive millimeter-wave radars, array antennas are developing along the trends of high gain, low loss, small size, and easy integration with planar circuits.

Microstrip array antennas mainly have three feeding methods: microstrip line edge feed, coaxial probe back feed and hole coupling feed. Among them, the edge feed feed design method is simple, and it is easy to adjust the antenna resonant frequency. The most commonly used form of radar antenna, but the feeding method of the feeder itself has a large radiation interference, many antenna side lobes, poor symmetry, and high requirements for antenna installation and calibration; coaxial probe backfeed will not affect the antenna Radiation, less side lobes, high gain, but the design is complex, difficult to select the feed point; hole coupling feed antenna radiation pattern side lobe is small, symmetry is better, but the gain is small, the design and matching of the hole is more difficult.

Contents of the invention

The invention provides a microstrip array antenna, which solves the problem that the structure design of the microstrip array antenna is complicated and difficult to realize in the related art.

As one aspect of the present invention, a microstrip array antenna is provided, wherein the microstrip array antenna includes: a substrate, a power divider, a microstrip uniform array and a metal waveguide, the first surface and the second surface of the substrate Both have wiring, and the power divider includes a first copper foil arranged on the first surface and a second copper foil arranged on the second surface, and the first copper foil and the second copper foil pass through The through-holes running through the substrate are connected, the microstrip uniform arrays are arranged on the first surface of the substrate and connected to the power divider, the metal waveguide is located at the position of the power divider, and runs through the power divider. The base plate is set, and the position of the metal waveguide on the base plate is provided with a coupling slot, and the coupling slot and the metal wave guide can feed the radio frequency input signal into the power splitter, and the power splitter can according to the The radio frequency input signal generates an equal-amplitude radio frequency output signal, and forms an antenna beam through the microstrip uniform array.

Further, the power divider includes a four-way power divider, and the four-way power divider can generate four equal-amplitude radio frequency output signals according to the radio frequency input signal.

Further, the microstrip array antenna includes four uniform microstrip lines, each of which is connected to the power splitter.

Further, each microstrip uniform front includes at least one unitary microstrip uniform front.

Further, each microstrip uniform front includes a nine-element microstrip uniform front.

Further, the shape of the coupling gap includes a dumbbell shape.

Further, the substrate includes a multi-layer PCB board.

Further, the substrate includes a double-layer PCB.

Through the above-mentioned microstrip array antenna, the metal waveguide is set, and the video input signal is fed to the power divider through the metal waveguide and the coupling gap, and the antenna beam is formed through the power divider and the microstrip uniform array. This microstrip array antenna structure has The antenna radiation pattern has the advantages of small side lobes, high gain, and good symmetry. At the same time, it has the advantages of simple structure, easy implementation, and convenient assembly and maintenance of the feeding method.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention. In the attached picture:

FIG. 1 is a schematic structural diagram of a microstrip array antenna provided by the present invention.

FIG. 2 is a schematic diagram of the first surface structure of the substrate of the microstrip array antenna provided by the present invention.

FIG. 3 is a schematic diagram of the second surface structure of the substrate of the microstrip array antenna provided by the present invention.

Fig. 4 is the direction diagram of H plane (azimuth plane) and E plane (elevation plane) of the microstrip array antenna provided by the present invention.

Fig. 5 is a 75-78GHz return loss S(1,1) diagram of the microstrip array antenna provided by the present invention.

Detailed ways

It should be noted that, in the case of no conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and examples.

In order to enable those skilled in the art to better understand the solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only Embodiments of some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific sequence or sequence. It should be understood that the data so used may be interchanged under appropriate circumstances for the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or device comprising a series of steps or elements that is not necessarily limited to the explicitly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.

In this embodiment, a microstrip array antenna is provided. FIG. 1 is a schematic structural diagram provided according to an embodiment of the present invention, as shown in FIGS. 1 to 3, including: a substrate 7, a power divider 1, and a microstrip uniform array antenna 2 and a metal waveguide 5, both the first surface and the second surface of the substrate 7 have wiring, and the power divider 1 includes a first copper foil arranged on the first surface 71 and a first copper foil arranged on the second surface 72 of the second copper foil, the first copper foil and the second copper foil are connected through the through hole 4 passing through the substrate 7, and the microstrip uniform array 2 is arranged on the first surface of the substrate 7 And connected to the power divider 1, the metal waveguide 5 is located at the position of the power divider 1, and is arranged through the substrate 7, and the position of the metal waveguide 5 on the substrate 7 is provided with a coupling gap 3 , the coupling slot 3 and the metal waveguide 5 can feed the radio frequency input signal into the power divider 1, and the power divider 1 can generate a radio frequency output signal of equal amplitude according to the radio frequency input signal, and pass The microstrip uniform array 2 forms an antenna beam.

Through the above-mentioned microstrip array antenna, the metal waveguide is set, and the video input signal is fed into the power splitter through the metal waveguide and the coupling gap, and the antenna beam is formed through the power splitter and the microstrip uniform array, which can be applied to 77GHz millimeter-wave radar. Through this feeding method, the side lobe of the antenna radiation pattern is small, the gain is high, and the symmetry is good. Compared with the traditional hole-coupled feeding method, the waveguide coupling gap is easier to process, and the feeding method has a simple structure, easy to realize, assemble and The advantage of easy maintenance.

It should be noted that the substrate 7 shown in FIG. 1 is a double-sided PCB, that is, both the upper surface and the lower surface are provided with copper foil. In this embodiment, the first surface may specifically be the upper surface, and the second surface may specifically be the lower surface.

Specifically, as shown in FIG. 1 , the power divider 1 includes a four-way power divider, and the four-way power divider can generate four equal-amplitude radio frequency output signals according to the radio frequency input signal.

More specifically, the microstrip array antenna includes four microstrip uniform arrays, and each microstrip uniform array is connected to the power divider.

Preferably, each microstrip uniform line includes at least one unitary microstrip uniform line.

Preferably, each microstrip uniform line includes a nine-element microstrip uniform line.

It can be understood that, as shown in FIG. 1 , four microstrip uniform fronts are arranged on the substrate 7, and each microstrip uniform front is connected to the power divider. Correspondingly, the power divider 1 is Four-way power splitter. In addition, each microstrip uniform array is provided with a nine-element microstrip uniform array. Therefore, the radio frequency input signal is fed into the power divider 1 through the metal waveguide 5 and the coupling gap 3 to generate four radio frequency output signals of equal amplitude. The RF output signals of the two channels are respectively fed into the corresponding four nine-element microstrip uniform linear arrays and superimposed to form an antenna beam with high gain, high efficiency and low sidelobe.

It should be noted that the number of elements on each microstrip uniform array is related to the direction of the antenna beam. Therefore, the number of microstrip uniform arrays on each microstrip uniform array can be set according to requirements, which is not limited here .

Specifically, in order to improve the coupling efficiency, the shape of the coupling slot 3 includes a dumbbell shape.

It should be noted that the electromagnetic signal in the metal waveguide radiates to the outside through the coupling slot, forms electromagnetic coupling with the power divider 1, and realizes antenna contactless feeding. By adjusting the shape and size of the coupling slot 3, a suitable Matching and maximum radiation to obtain broadband VSWR characteristics. Compared with the general rectangular slit, the dumbbell-shaped structural coupling slit in this embodiment can provide more design freedom and optimization space. By adjusting the different components of the dumbbell-shaped pattern, the coupling strength, bandwidth and impedance variation range can be adjusted. Adjust separately.

Specifically, the substrate 7 includes a multi-layer PCB board.

It should be noted that the substrate 7 may include a multi-layer PCB, and power feeding is realized through coupling slots and metal waveguides.

Preferably, the substrate 7 includes a double-layer PCB. Figure 1 takes a double-layer PCB as an example to illustrate.

The structure and working principle of the microstrip array antenna provided by the present invention will be described in detail below with reference to FIG. 1 to FIG. 3 .

The microstrip array antenna provided in this embodiment is composed of a power divider 1 , a microstrip uniform linear array 2 , a coupling slot 3 , a through hole 4 , a metal waveguide 5 and a substrate 7 and other elements. The power divider 1 is formed by double-sided photoetching on the substrate 7. It consists of the top copper foil (located on the upper surface of the substrate) and the bottom copper foil (located on the lower surface of the substrate) of the power divider containing four-way gradual output arms. ), and a dumbbell-shaped coupling gap 3 as the input port of the power divider and a through hole 4, wherein the copper foil on the top surface of the power divider and the copper foil on the bottom surface of the substrate are electrically interconnected through the through hole 4.

Working principle: The RF input signal is fed into the power divider 1 through the metal waveguide 5 and the dumbbell-shaped coupling gap 3 to generate four RF output signals of equal amplitude, and these four RF output signals are respectively fed into the corresponding four nine-element microstrips The uniform linear array 2 is superimposed to form an antenna beam with high gain, high efficiency and low sidelobe.

Figure 4 shows the H plane (azimuth plane) and E plane (pitch plane) pattern of the microstrip array antenna provided in this embodiment. It can be seen from Figure 4 that the microstrip array antenna pattern of this embodiment has good symmetry , less sidelobe and higher gain.

FIG. 5 is a 75-78GHz return loss S(1,1) diagram of the microstrip array antenna provided in this embodiment. It can be seen from Figure 5 that the antenna impedance is relatively wide, greater than 1GHz (return loss S(1,1) is lower than -10dB), which fully meets the antenna bandwidth requirements of 76-77GHz.

Therefore, the microstrip array antenna provided in this embodiment has the following advantages:

(1) The input port of the dumbbell-shaped coupling slot pattern of the power splitter reduces the size of the input port and the overall size of the power splitter when the microstrip antenna array metal waveguide backfeeds;

(2) The power splitter and the microstrip uniform line array are combined to form a microstrip antenna array, which realizes high gain, high efficiency and low sidelobe microstrip array antenna;

(3) The microstrip array antenna consists of a double-sided printed circuit board and a metal waveguide, which has a simple structure and is convenient for assembly and maintenance.

(4) The microstrip antenna array has good symmetry, no feeder radiation interference, less side lobes of antenna radiation, good symmetry of the pattern, high efficiency and high gain.

(5) The waveguide slot coupling feeding method based on substrate integrated waveguide (SIW) technology is adopted, which has high feeding efficiency and large antenna gain, which can meet the higher bandwidth requirements of the antenna.

It can be understood that, the above embodiments are only exemplary embodiments adopted for illustrating the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims (8)

1. a kind of micro-strip array antenna, which is characterized in that the micro-strip array antenna includes: substrate, power splitter, the uniform battle array of micro-strip Line and metal waveguide, the first surface and second surface of the substrate have a wiring, and the power splitter includes setting described the First copper foil on one surface and the second copper foil that the second surface is arranged in, first copper foil and second copper foil pass through Through-hole through the substrate connects, and the uniform front of micro-strip is arranged at the first surface of the substrate and divides with the function Device connection, the metal waveguide is located at the power splitter position, and is arranged through the substrate, the gold on the substrate Belong to waveguide position and be provided with coupling gap, the coupling gap and the metal waveguide can be by radio-frequency input signals feed-ins To the power splitter, the power splitter can generate the radio frequency output signal of constant amplitude according to the radio-frequency input signals, and pass through The uniform front of micro-strip forms antenna beam.

2. micro-strip array antenna according to claim 1, which is characterized in that the power splitter includes four road power splitters, institute The radio frequency output signal of four tunnel constant amplitudes can be generated according to the radio-frequency input signals by stating four road power splitters.

3. micro-strip array antenna according to claim 2, which is characterized in that the micro-strip array antenna includes four micro-strips Uniform front, the uniform front of every micro-strip connect with the power splitter.

4. micro-strip array antenna according to claim 3, which is characterized in that the uniform front of every micro-strip includes at least one First uniform front of micro-strip.

5. micro-strip array antenna according to claim 4, which is characterized in that the uniform front of every micro-strip includes nine yuan micro- With uniform front.

6. micro-strip array antenna according to claim 1, which is characterized in that the shape in the coupling gap includes dumbbell Type.

7. micro-strip array antenna according to claim 1, which is characterized in that the substrate includes multi-layer PCB board.

8. micro-strip array antenna according to claim 7, which is characterized in that the substrate includes double-layer PCB board.