CN108493626A - A four-element dual-polarized microstrip antenna array based on SIC technology - Google Patents

Abstract

The invention relates to a four-element dual-polarized microstrip antenna array based on SIC technology, which comprises a six-layer printed circuit board and metal pillars (6), and a rectangular parasitic patch (1) is printed on the lower surface of the top printed circuit board (17) , the upper surface of the third layer printed circuit board (16) is printed with a rectangular main patch (2) and the main patch layer reflector (11), and the upper surface of the fourth layer printed circuit board (15) is printed with a vertically polarized feeder ( 3) and the ring (8), the upper surface of the fifth layer printed circuit board (14) is printed with a grounding plate (4), and the grounding plate (4) is etched with a cross-shaped slit (9), a circular opening (19) and Circular opening (20), horizontally polarized feeder (5) and stripline (10) are printed on the lower surface of the fifth-layer printed circuit board (14), and the bottom surface of the bottom printed circuit board (12) is provided with an antenna bottom reflector board (13). The invention has wider bandwidth, higher port isolation and lower cross polarization level.

Description

A four-element dual-polarized microstrip antenna array based on SIC technology

technical field

The invention relates to a microstrip antenna array, in particular to a four-unit dual-polarization microstrip antenna array based on SIC technology, which belongs to the technical field of antennas.

Background technique

With the wide application of wireless communication and radar detection, modern antennas need to meet the requirements of large-capacity communication and integration of sending and receiving, which requires the antenna to be able to achieve broadband, dual polarization and other characteristics. Microstrip antennas have the advantages of small size, light weight, and easy conformality, and some frequency band widening technologies, such as aperture coupling feeding, U-shaped slot patches, and high dielectric constant dielectric patches, can meet the bandwidth requirements of different applications. Therefore, designing dual-polarized antennas on the basis of microstrip antennas has become a major trend in antenna design. The methods of microstrip antenna to achieve dual polarization are: array combination dual polarization, through the combination of two polarizations orthogonal to single polarization, the dual polarization function of the array is realized. This structure is bulky and costly, so its application is limited Restrictions: unit dual polarization, through the special structural design of the antenna unit, the polarization function in two directions can be realized on the same antenna unit at the same time. This structure is small in size, light in weight and low in cost, so it is widely used by antenna scholars focus on. However, the dual polarization of the unit will also cause mutual interference between ports, which is the problem of isolation and cross polarization.

Contents of the invention

In view of the above prior art, the technical problem to be solved by the present invention is to provide a four-unit dual-polarization microstrip based on SIC technology with wider bandwidth, higher port isolation, and lower cross-polarization level antenna array.

In order to solve the above-mentioned technical problems, a four-element dual-polarization microstrip antenna array based on SIC technology of the present invention includes: six layers of printed circuit boards arranged up and down and sixty-four metal pillars 6, the bottom layer of the top printed circuit board 17 Four identical rectangular parasitic patches 1 are printed on the surface, four identical rectangular main patches 2 and main patch layer reflectors 11 are printed on the upper surface of the third layer printed circuit board 16, and the fourth layer printed circuit board The upper surface of 15 is printed with vertically polarized feeder 3 and ring 8, the upper surface of the fifth-layer printed circuit board 14 is printed with grounding plate 4, and four cross-shaped gaps 9 and sixty-four metal pillars are etched on the grounding plate 4 A circular opening 19 and a circular opening 20 of a vertical transition structure, the lower surface of the fifth layer printed circuit board 14 is printed with a horizontally polarized feeder 5 and a stripline 10, the stripline 10 passes through the metal via 7 and the vertical The circular ring 8 of the polarized feeder 3 is connected, and the bottom surface of the bottom printed circuit board 12 is provided with an antenna bottom reflection plate 13, and every sixteen metal pillars 6 are arranged at equal intervals around the rectangular main patch 2, and sixty-four metal pillars 6 passes through the corresponding circular opening 19 of the metal pillar, and the two ends of the metal pillar are respectively connected to the reflector 11 of the main patch layer and the reflector 13 of the antenna bottom layer to form a substrate integrated cavity back structure.

A kind of four-unit dual-polarized microstrip antenna array based on SIC technology of the present invention also includes:

1. The second layer of printed circuit board 18 and the bottom layer of printed circuit board 12 are foam layers, the top layer of printed circuit board 17, the third layer of printed circuit board 16, the fourth layer of printed circuit board 15 and the fifth layer of printed circuit board 14 are medium substrate.

2. Both the rectangular main patch 2 and the rectangular parasitic patch 1 are square, and the four rectangular main patches 2 are arranged in a square, and the interval between two rectangular main patches on the same side is 0.87 times the wavelength of the medium of the dielectric substrate.

3. Each rectangular parasitic patch 1 is located directly above the corresponding rectangular main patch 2 and its side length is greater than that of the rectangular main patch 2 .

4. The centers of the rectangular parasitic patch 1, the rectangular main patch 2, and the cross-shaped slit 9 are aligned vertically.

5. The dual-polarized microstrip antenna array based on SIC technology adopts equal-amplitude anti-phase inversion feeding technology.

6. The radius of the metal pillars 6 is 0.5mm, and the distance between the metal pillars is 2.6mm.

Beneficial effects of the present invention: Compared with the general dual-polarized microstrip antenna, the antenna has wider bandwidth, higher port isolation, and lower cross-polarization level, and can be better applied to radar detection, field of satellite communications. The antenna has the advantages of low profile, small size, and low cost. As a derivative technology of Substrate Integrate Waveguide (SIW) technology, Substrate Integrate Cavity (SIC) technology has the characteristics of low insertion loss, low loss and high efficiency of waveguide structure. , the structure can also be easily integrated in the printed circuit, the main role is to reduce the back radiation, while increasing the bandwidth of the antenna. The antenna is designed on the basis of microstrip antenna. The antenna integrates feed and radiation. It has a simple structure and is produced by printed circuit technology. It has the advantages of low profile, light weight, high precision, and low cost. The antenna adopts SIC technology , parasitic patch technology, slot coupling technology to increase the antenna capacitive, reduce the antenna Q value to improve the antenna operating bandwidth; the antenna adopts SIC technology and uses sixty-four metal pillars to form a substrate integrated back cavity structure, reducing the antenna back At the same time, it reduces the mutual coupling between feeders and the influence of feeder radiation on the array, improves the isolation between ports and reduces cross-polarization; the antenna adopts reverse-phase inversion feeding technology, so that the cross-polarization components between elements cancel each other, Reduced antenna array cross-polarization levels.

Description of drawings

Fig. 1 is the top view of the four-element dual-polarization microstrip antenna array array based on SIC technology of the present invention;

Fig. 2 is a side view of the four-unit dual-polarized microstrip antenna array array based on the SIC technology of the present invention;

Fig. 3 is the top view of the parasitic patch of the four-element dual-polarized microstrip antenna array based on the SIC technology of the present invention;

Fig. 4 is the four-unit dual-polarized microstrip antenna array rectangular main patch 2 and the top view of the main patch layer reflector 11 of the present invention based on SIC technology;

5 is a top view of the structure of the four-element dual-polarized microstrip antenna array vertically polarized feeder 3 based on the SIC technology of the present invention;

6 is a top view of the structure of the four-unit dual-polarized microstrip antenna array aperture coupling cross slot 9 based on the SIC technology of the present invention;

FIG. 7 is a top view of the structure of the four-element dual-polarized microstrip antenna array horizontally polarized feeder 5 based on the SIC technology of the present invention;

Fig. 8 is a structural diagram of sixty-four metal pillars of the four-unit dual-polarized microstrip antenna array substrate integrated back chamber based on the SIC technology of the present invention;

Fig. 9 is the relationship figure between the VSWR of the four-unit dual-polarized microstrip antenna array based on the SIC technology and the phase difference and frequency of the four-way feed network of the present invention;

Fig. 10 is the relationship diagram of the horizontal polarization and vertical polarization impedance bandwidth and frequency of the four-element dual-polarized microstrip antenna array based on SIC technology in the present invention;

Figure 11(a) is a four-element dual-polarized microstrip antenna array based on SIC technology with horizontal polarization, E-plane, H-plane gain and port isolation relationship with pitch angle;

Figure 11(b) is a diagram of the vertical polarization of the four-element dual-polarized microstrip antenna array based on the SIC technology, the relationship between the gain of the E plane and the H plane, and the port isolation and the pitch angle;

Figure 11(c) is a four-element dual-polarized microstrip antenna array horizontally polarized without using SIC technology, and the relationship between E-plane and H-plane gain and port isolation and pitch angle;

Figure 11(d) is a graph of the relationship between the vertical polarization of the four-element dual-polarized microstrip antenna array without using SIC technology, the gain of the E plane, the H plane, and the port isolation and the pitch angle;

Fig. 12 is a graph showing the relationship between the horizontal polarization and vertical polarization isolation and frequency of the four-element dual-polarized microstrip antenna array based on the SIC technology of the present invention with or without the SIC structure.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

This embodiment provides a four-unit dual-polarized microstrip antenna array based on SIC technology, with a center frequency of 9.6 GHz. Its structure is shown in Figures 1 to 2, mainly including:

As shown in Figure 3, the dielectric substrate 17 is Rogers 5880 with a dielectric constant of 2.2 and a thickness of 1.016 mm. The bottom layer of the dielectric 17 is printed with four square parasitic stickers with a spacing of 0.87 times the wavelength of Rogers 5880, that is, 18.5 mm. slice 1.

The dielectric substrate 18 is made of Rohacell HF51 foam with a dielectric constant of 1.07 and a thickness of 3 mm.

As shown in Figure 4, the dielectric substrate 16 is Rogers 5880 with a dielectric constant of 2.2 and a thickness of 1.016 mm. The top layer of the dielectric 16 is printed with a main patch layer reflector 11 and four Rogers 5880 dielectrics with a spacing of 0.87 times. The wavelength, that is, the square main patch 2 of 18.5mm.

As shown in FIG. 5 , the dielectric substrate 15 is Rogers 5880 with a dielectric constant of 2.2 and a thickness of 0.508 mm. The vertically polarized feeder 3 is printed on the top layer of the dielectric 15 .

As shown in Figure 6, Figure 7 and Figure 8, the dielectric substrate 14 is Rogers 5880 with a dielectric constant of 2.2 and a thickness of 0.508mm. The top layer of the dielectric 14 is printed with a grounding plate 4 with a cross-shaped gap 9, The bottom layer is printed with a horizontally polarized feeder 5, and sixty-four metal pillars 6 with a radius of 0.5mm pass through the sixty-four metal pillar circular openings 19 of the grounding plate 4, and are connected to the reflector 11 of the main patch layer and the bottom layer of the antenna. The reflector 13 forms the substrate integrated back cavity inside the antenna; the metal via hole 7 with a radius of 0.2mm passes through the dielectric substrate 14 and the dielectric substrate 15, and the two ends are respectively connected to the strip line 10 and the ring 8 of the vertically polarized feeder Form a vertical transition structure.

The dielectric substrate 12 is made of Rohacell HF51 foam with a dielectric constant of 1.07 and a thickness of 2.5mm. The bottom layer of the dielectric 12 is printed with an antenna bottom reflection plate 13 .

As shown in Figure 9, Figure 10, Figure 11(a), Figure 11(b), Figure 11(c), Figure 11(d) and Figure 12, the microstrip array antenna provided by the embodiment of the present invention can be 30mm in length Within the size of 30mm wide and 8.548mm thick, the impedance bandwidth of the vertically polarized port is 28.51% (8.27-11.02GHz) and the impedance bandwidth of the horizontally polarized port is 31.76% (8.05-11.09GHz). The isolation within the bandwidth range is better than 42dB. Cross-polarization and vertical cross-polarization are below -48dB and -35dB performance, respectively.

Embodiments of the present invention also include:

As shown in Figures 1 to 8, a 4-element dual-polarized microstrip antenna array based on SIC technology, the antenna array uses microstrip antenna technology to obtain low-profile, low-cost characteristics, and uses parasitic patch technology to increase antenna bandwidth. Slot-coupling technology is used to increase antenna bandwidth and achieve dual polarization, and reverse-phase inversion feeding technology is used to reduce cross-polarization level. The antenna includes six-layer printed circuit boards and sixty-four integrated metal pillars.

The six-layer printed circuit board is characterized in that media 12 and 18 are Rohacell HF51 foam, media 14, 15, 16, and 17 are Rogers 5880 dielectric boards, and the bottom layer of media 17 is printed with rectangular parasitic patch 1, and the top layer of media 16 is printed with rectangular The main patch 2 and the main patch layer reflector 11, the vertically polarized feeder 3 is printed on the top layer of the medium 15, the grounding plate 4 is printed on the top layer of the medium 14, and the grounding plate 4 is etched with four cross-shaped slits 9 and sixty Four metal pillar circular openings 19, a vertical transition structure circular opening 20, the bottom layer of the dielectric 14 is printed with a horizontally polarized feeder 5 and a stripline 10, and the stripline 10 is connected to the vertically polarized through the metal via 7. The feeder 3 is connected, and the antenna bottom reflector 13 is placed on the bottom of the dielectric board 12. The sixty-four metal pillars are characterized in that the sixteen metal pillars are evenly arranged around the rectangular main patch 2 at a distance of 2.6 mm. The patch layer reflector 11 and the antenna bottom reflector 13 form a substrate-integrated cavity-back structure.

The rectangular parasitic patch 1 is located directly above the rectangular main patch 2, and the side length is slightly larger than the rectangular main patch 2, and the range is between 0.1mm and 2mm.

The rectangular parasitic patch 1 and the rectangular main patch 2 are excited by the cross-shaped slit 9 directly below them.

Vertically polarized feeders 3 and horizontally polarized feeders 5 that are perpendicular to each other are arranged on the upper surface of the dielectric board 15 and the lower surface of the dielectric board 14 respectively.

Both vertically polarized feeder 3 and horizontally polarized feeder 5 consist of a 50Ω to 100Ω T-shaped power divider, two 100Ω to 25Ω multi-section impedance converters, two 25Ω to 50Ω T-shaped power dividers and four L Shaped feeder composition.

The vertically polarized feeder 3 and the horizontally polarized feeder 5 have a similar U-shaped structure.

The sixty-four metal pillars 6 are characterized in that sixteen metal pillars form a group and are evenly arranged around the rectangular main patch 2, and the two ends of the integrated metal pillars are connected to the main patch layer reflector 11 and the antenna bottom reflector 13, Composing the substrate integrated back cavity structure.

The metal via hole 7 with an internal radius of 0.2mm passes through the dielectric board 14 and the dielectric board 15, and the two ends are respectively connected with the strip line 10 and the ring 8 of the vertically polarized feeder 3 to form a vertical transition structure, reducing the back radiation.

The cross-shaped coupling slot 9 is etched on the ground plate 4, and the arm length of the cross-shaped slot 9 is slightly different due to the different distances between the feeder and the radiation patch.

The different distances between the vertically polarized feeder 3 and the horizontally polarized feeder 5 from the radiation patch lead to slightly different sizes of the two feeders

Embodiments of the present invention also include:

As shown in Figures 1 to 8, a wide-band high-isolation low cross-polarization dual-polarization microstrip antenna array based on SIC technology, including six-layer printed circuit boards and sixty-four metal pillars, six-layer printed circuit boards It is characterized in that media 12 and 18 are RohacellHF51 foam, media 14, 15, 16 and 17 are Rogers 5880 media boards, the bottom layer of media 17 is printed with rectangular parasitic patches 1, and the top layer of media 16 is printed with rectangular main patches 2 and The main patch layer reflector 11, the vertically polarized feeder 3 is printed on the top layer of the medium 15, the ground plate 4 is printed on the top layer of the medium 14, and four cross-shaped slits 9 and sixty-four metal pillar circles are etched on the ground plate 4 shaped opening 19, a circular opening 20 with a vertical transition structure, the bottom layer of the medium 14 is printed with a horizontally polarized feeder 5 and a stripline 10, the stripline 10 is connected to the vertically polarized feeder 3 through a metal via 7, and the antenna The bottom reflection plate 13 is placed on the bottom layer of the dielectric plate 12. The sixty-four metal pillars are characterized in that the sixteen metal pillars are evenly arranged around the rectangular main patch 2 at a distance of 2.6mm, which is the same as that of the main patch layer reflector. 11. The reflector 13 at the bottom of the antenna constitutes a substrate-integrated back cavity structure.

The distance between the rectangular main patches 2 is 0.87 times the wavelength of the medium, that is, 18.5 mm.

The microstrip antenna array adopts equal-amplitude anti-phase inversion feeding technology, that is, the feeding point is mirror-symmetrical, and the feeder output phase difference is 180 degrees of equal-amplitude signal.

The rectangular main patch 2 is surrounded by a substrate-integrated back cavity.

The centers of the rectangular parasitic patch 1 , the rectangular main patch 2 , and the cross-shaped slit 9 are vertically aligned.

The vertically polarized feeder 3 and the horizontally polarized feeder 5 are printed on both sides of the ground plate 4 respectively.

The metal pillars 6 of the substrate-integrated back cavity surrounding the antenna radiation unit have a radius of 0.5 mm and a spacing of 2.6 mm.

The invention discloses a four-unit dual-polarized microstrip antenna array based on SIC technology. The antenna array uses technologies such as microstrip antenna technology, SIC technology, parasitic patch technology, slot coupling technology, and reverse inversion feeding technology. The wide bandwidth, high isolation, low cross polarization, and low feed radiation of the microstrip antenna are realized. The antenna is based on a cross-shaped slot-coupled microstrip antenna, and adopts a multi-layer structure to increase the capacitance of the antenna and reduce the Q value of the antenna to expand the bandwidth. Sixteen metal pillars are evenly embedded around each array unit to form a substrate integrated back cavity to reduce back radiation. The reflector inside the array isolates the two-layer feed network and suppresses the electromagnetic radiation of the feed microstrip line to improve antenna isolation and reduce cross-polarization. The antenna realizes the planarization and miniaturization of the dual-polarization antenna array, and can realize the integrated integration of the antenna and the circuit. The invention belongs to the microstrip patch antenna, which can be used in satellite communication, radar positioning, synthetic aperture radar and many other aspects.

Claims (7)

1. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies, it is characterised in that：The print arranged including about six layers Printed circuit board and 64 metal mainstays (6), there are four identical rectangles for the lower surface printing of top layer printed circuit board (17) Parasitic patch (1), there are four the main patch of identical rectangle (2) and main patch layers for the printing of third layer printed circuit board (16) upper surface Reflecting plate (11), the 4th layer printed circuit board (15) upper surface are printed with vertical polarization feeder line (3) and annulus (8), layer 5 print Earth plate (4) is printed in printed circuit board (14) upper surface, and there are four cross gap (9), 64 gold for etching on earth plate (4) Belong to pillar round hole (19) and a vertical transition structure round hole (20), layer 5 printed circuit board (14) lower surface print It is formed with horizontal polarization feeder line (5) and strip line (10), strip line (10) passes through metallic vias (7) and vertical polarization feeder line (3) Annulus (8) be connected, printed circuit board (12) lower surface is provided with antenna bottom reflecting plate (13), every 16 metal branch Column (6) is equally spacedly arranged in the main patch of rectangle (2) surrounding, and 64 metal mainstays 6 pass through corresponding metal mainstay round Trepanning (19), and the both ends of metal mainstay are separately connected main patch layer reflecting plate (11) and antenna bottom reflecting plate (13) and common It constitutes substrate and integrates back cavity structure.

2. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 1, it is characterised in that： Second layer printed circuit board (18) and printed circuit board (12) are froth bed, top layer printed circuit board (17), third layer print Printed circuit board (16), the 4th layer printed circuit board (15) and layer 5 printed circuit board (14) are medium substrate.

3. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 1 or 2, feature exist In：The main patch of rectangle (2) and rectangle parasitic patch (1) are square, the square arrangement of four main patches of rectangle (2) and same It is divided into 0.87 times of medium substrate medium wavelength between two main patches of rectangle on one side.

4. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 3, it is characterised in that： Each rectangle parasitic patch (1) is respectively positioned on the surface of the corresponding main patch of rectangle (2) and the length of side is all higher than the main patch of rectangle (2) The length of side.

5. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 4, it is characterised in that： Rectangle parasitic patch (1), the main patch of rectangle (2), cross gap (9) center vertically aligned.

6. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 1 or 2, feature exist In：Dual-polarized Micro Strip Array based on SIC technologies is inverted feeding technique using constant amplitude reverse phase.

7. a kind of four unit Dual-polarized Micro Strip Arrays based on SIC technologies according to claim 1, it is characterised in that： The radius of the metal mainstay (6) is 0.5mm, spacing 2.6mm between metal mainstay.