CN116435763A - Millimeter wave super-surface radar receiving antenna, transmitting antenna and receiving and transmitting integrated antenna - Google Patents

Abstract

The invention discloses a millimeter wave super-surface radar receiving antenna, a transmitting antenna and a receiving and transmitting integrated antenna, which sequentially comprise an upper medium substrate, a first metal plate, a prepreg, a lower medium substrate and a second metal plate from top to bottom, wherein the upper surface of the upper medium substrate is provided with a receiving super-surface structure, a receiving feed gap is etched on the first metal floor, a receiving strip feeder is arranged between the prepreg and the lower medium substrate, and a metal through hole is arranged between the upper surface of the upper medium substrate and the second metal plate around the receiving super-surface structure, the receiving feed gap and the receiving strip feeder to form a self-shielding cavity of the receiving antenna. The millimeter wave radar transceiver antenna has the characteristics of small size, low section, compact structure and simple processing, and can ensure that the millimeter wave radar transceiver antenna realizes high transceiver isolation and higher harmonic suppression.

Description

Millimeter-wave metasurface radar receiving antenna, transmitting antenna and integrated transmitting and receiving antenna

technical field

The invention relates to the field of millimeter wave communication, in particular to a millimeter wave metasurface radar receiving antenna, a transmitting antenna and an integrated transmitting and receiving antenna.

Background technique

With the development of millimeter wave technology, many unique functions of the phased array antenna, such as the ability to simultaneously search, identify and track the air, as well as the ability of high power, high data and resistance to environmental conditions, have greatly promoted the phased array antenna. Research design and equipment of array antenna. Nowadays, commercial applications in vehicle, early warning radar, wireless communication, and radio frequency identification have higher and higher requirements for antennas, especially for flexible control of antenna patterns.

However, the high cost of phased array antennas seriously restricts its application range. The low-cost design method of active phased array antennas is an important direction for the development of electronic scanning antennas, and it is also an important prerequisite for the formation of serialized products of phased array antennas. In addition, the working frequency band of the active phased array antenna is usually the X frequency band to the millimeter wave frequency band. The higher the operating frequency, the smaller the area of each radiation unit, and the higher the integration requirements. The traditional design method of simple assembly of subsystem modules can no longer meet the requirements of array layout and maintenance. Highly integrated integrated design technology must be used to achieve the goal of thinner, scalable and low-cost active phased array antennas.

Contents of the invention

In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the object of the present invention is to provide a millimeter-wave metasurface radar receiving antenna, transmitting antenna and integrated transmitting and receiving antenna. The invention not only has the characteristics of small size, low profile, compact structure and simple processing, but also can ensure that the millimeter-wave radar transceiver antenna realizes high transceiver isolation and high-order harmonic suppression.

The object of the present invention is achieved through the following technical solutions:

A millimeter-wave metasurface radar receiving antenna comprises an upper layer dielectric substrate, a first metal plate, a prepreg, a lower layer dielectric substrate and a second metal plate from top to bottom, and the upper surface of the upper layer dielectric substrate is provided with a receiving metasurface structure, The first metal floor is etched with receiving feeder slits, a receiving strip-shaped feeder is arranged between the prepreg and the lower dielectric substrate, and the receiving metasurface structure and the receiving The feeding slot and the receiving strip feeder are provided with metal through holes to form a self-shielding cavity for the receiving antenna.

Further, the receiving metasurface structure is composed of M×N receiving ring-shaped patch units arranged in a centrally symmetrical periodic arrangement.

Further, the receiving feeding slot is an H-shaped slot, which is excited by the receiving strip feeder, and further excites the upper receiving metasurface structure to generate linearly polarized radiation.

Further, the receiving strip feeder is a single-ended strip feeder.

A millimeter-wave metasurface radar transmitting antenna, comprising an upper dielectric substrate, a first metal plate, a prepreg, a lower dielectric substrate and a second metal plate from top to bottom, the upper surface of the upper dielectric substrate is provided with a transmitting metasurface structure, the Etch the transmitting and feeding slit on the first metal floor, and set the transmitting strip-shaped feeder between the prepreg and the lower dielectric substrate, and the transmitting strip-shaped feeder also includes an open circuit branch, on the upper surface of the upper dielectric substrate and the second metal Metal through holes are arranged between the plates around the transmitting metasurface structure, the transmitting feed slot and the transmitting strip feeder to form a self-shielding cavity of the transmitting antenna.

Further, the emitting metasurface structure includes M×N emitting ring patch units arranged periodically in a centrally symmetrical manner, and a square patch is arranged in each emitting ring patch unit.

Further, the transmitting feeding slot is an I-shaped slot, which is excited by the transmitting strip feeder, and further excites the transmitting metasurface structure to generate linearly polarized radiation.

Further, the transmitting strip feeder is a double-ended differential feeder.

Further, the open-circuit stub suppresses the third and fifth harmonic energies in the shape of two quarter-wavelength sectors.

Further, a row of metal via holes is provided on one side of the square patch, and is located in the emission ring patch unit.

Further, the I-shaped slit deviates from the central position of the transmitting metasurface structure, so as to realize the suppression of the fifth harmonic energy pair.

A self-shielded millimeter-wave metasurface radar transceiver integrated antenna, including a receiving antenna and a transmitting antenna, the receiving antenna and the transmitting antenna are symmetrically arranged on both sides of the antenna, and the central connection line of the two is perpendicular to the polarization direction of the antenna, and the receiving antenna And the middle position of the transmitting antenna is provided with a decoupling structure that suppresses the energy coupling of the transmitting and receiving antenna, and the feed point is concentrated at the center position of the bottom of the antenna, and the receiving antenna is specifically the receiving antenna of the millimeter wave metasurface radar described in any one of claims 1-4. The antenna, the transmitting antenna is specifically the millimeter-wave metasurface radar transmitting antenna described in any one of claims 5-11.

Further, the decoupling structure includes a periodic arrangement of rectangular metal strips, and a ground metal via is arranged in each rectangular metal strip.

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

(1) The present invention symmetrically arranges the self-shielded receiving antenna and the self-shielded transmitting antenna on both sides of the antenna respectively. It eliminates the complexity of the feed network and ensures the easy integration, symmetry and compact structure of the transceiver antenna.

(2) The present invention adopts the simple processing technology of four-layer board PCB, and completely surrounds the metasurface structure, the feeding slot and the strip feeder of the receiving antenna and the transmitting antenna by setting a self-shielding cavity, and suppresses the energy of the strip feeder. While leaking, it avoids the difficult-to-achieve setting of blind and buried holes, and realizes the independence of the receiving antenna and the transmitting antenna itself

(3) The present invention adopts the ring-shaped metasurface structure as the radiator to reduce the area occupied by the metasurface antenna and the self-shielding cavity.

(4) The present invention reduces the area occupied by the feeding network and the self-shielding cavity by reducing the wiring of the strip feeder and adopting H-shaped and "I"-shaped feeding gaps.

(5) The present invention realizes energy suppression of the third and fifth harmonics by setting two quarter-wavelength fan-shaped open circuit stubs on the strip feeder of the self-shielding transmitting antenna.

(6) The present invention further improves the suppression of the fifth harmonic energy of the transmitting antenna by setting an asymmetric feeding slot deviated from the center of the radiation patch on the first metal plate of the self-shielding transmitting antenna.

(7) The present invention reduces the cavity size of the feeding network by setting two rows of metal vias that bridge the upper surface of the upper dielectric plate and the second metal plate in the annular patch of the self-shielded transmitting antenna, and further improves the transmitting antenna The third harmonic energy is suppressed while improving the impedance matching characteristics of the antenna.

(8) The present invention improves the impedance matching characteristics of the antenna by arranging a square patch in the self-shielding transmitting antenna square ring patch.

(9) The present invention uses a periodically arranged decoupling structure to realize high isolation between the single port and the differential port of the transceiver antenna.

(10) The present invention has the characteristics of small size, low profile, compact structure, simple processing, and low cost, and thus can realize large-scale production.

Description of drawings

Fig. 1 is a three-dimensional schematic diagram of the structure of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Figure 2(a) is a top view of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Fig. 2(b) is a side view of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Fig. 3(a) is a top view and a schematic diagram of the dimensions of the upper dielectric plate of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Fig. 3(b) is a top view and a schematic diagram of the size of the first layer of the metal plate of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Fig. 3(c) is a schematic diagram and a schematic diagram of the dimensions of the strip feeder line of the self-shielded millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

Fig. 4 is a result diagram of S parameters of the self-shielding millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention;

FIG. 5 is a radiation pattern diagram of the receiving antenna in Embodiment 1 of the present invention;

FIG. 6 is a radiation pattern diagram of the transmitting antenna in Embodiment 1 of the present invention;

FIG. 7 is a result diagram of the high-order harmonic efficiency of the transmitting antenna in Embodiment 1 of the present invention;

Fig. 8 is a gain result diagram of the self-shielded millimeter-wave radar transceiver integrated antenna in Embodiment 1 of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the examples, but the embodiments of the present invention are not limited thereto.

Example

As shown in Figure 1, Figure 2(a) and Figure 2(b), a self-shielding millimeter-wave metasurface radar transceiver integrated antenna adopts multi-layer PCB processing technology, and the entire antenna uses Roger5880 as the dielectric substrate. The dielectric constant ε _r of the dielectric substrate is [1, 10.2], the thickness is [0.01λ, 0.3λ], and the thickness of the metal floor is [0.005λ, 0.1λ], where λ is the free space wavelength.

Specifically, it includes a self-shielded receiving antenna 6, a self-shielding transmitting antenna 7, and a decoupling structure 16 that suppresses the energy coupling of the transmitting and receiving antennas. The self-shielding receiving antenna 6 and the self-shielding transmitting antenna 7 are symmetrically placed on both sides of the antenna. , the line connecting the centers of the two is perpendicular to the polarization direction of the antenna, and the feed point is concentrated at the center of the bottom of the antenna; the decoupling structure 16 for suppressing the energy coupling of the transmitting and receiving antenna is arranged at the center of the two.

The coupling structure is composed of periodically arranged square metal patches and ground metal vias arranged on the upper dielectric substrate 1, which effectively suppresses the gap between the single port of the self-shielded receiving antenna 6 and the differential port of the self-shielded transmitting antenna 7. energy coupling.

In this embodiment, the coupling structure includes 3*2 square metal patches, and each square metal patch is provided with a ground metal via hole.

Further, as shown in FIG. 3(a), FIG. 3(b) and FIG. 3(c), the self-shielded receiving antenna includes an upper dielectric substrate 1, a first metal plate 2, a prepreg 3, The lower dielectric substrate 4 and the second metal plate 5, the upper surface of the upper dielectric substrate 1 is provided with a receiving metasurface structure 8, the first metal floor 2 is etched with a receiving feed slit 10, the prepreg 3 and the lower dielectric substrate 4 A receiving strip feeder 12 is arranged between them, and metal through holes are arranged around the receiving metasurface structure 8, the receiving feed slot 10 and the receiving strip feeder 12 between the upper surface of the upper dielectric substrate 1 and the second metal plate 5, forming A self-shielding cavity 14 for the receiving antenna.

In this embodiment, the receiving metasurface structure is composed of M×N receiving annular patch units arranged in a center-symmetrical periodic manner. The annular design increases the surface current path of the metasurface structure and effectively reduces the size of the metasurface structure; the annular patch unit is not limited to a square annular structure, and may also be a parallelogram, trapezoid, or rhombus annular structure.

Further, in this embodiment, the receiving ring patch unit is a square ring, and the receiving metasurface structure includes 2*1 square ring patch units.

Further, in this embodiment, the receiving and feeding slot 10 is an H-shaped slot, which is etched on the first metal plate, and is excited by the strip feeder, and then excites the upper annular metasurface structure to generate linearly polarized radiation; the There is only one slot for receiving and feeding, and the shape of the feeding slot is not limited, and it can be H-shaped, U-shaped, I-shaped or transverse.

The receiving strip feeder of the self-shielded receiving antenna 6 adopts the form of a strip line, which is a single-ended strip feeder; the strip feeder transitions from the grounded coplanar waveguide 17 arranged at the bottom of the antenna to the on the strip feeder, and use straight lines, arcs, or 45-degree angles to route to perpendicular to the H-shaped feed slot and excite; the single-ended strip feeder of the self-shielded receiving antenna passes through a quarter-wavelength impedance Transformation realizes impedance matching adjustment.

In this embodiment, the millimeter-wave metasurface radar receiving antenna adopts a simple four-layer PCB processing technology, and the self-shielding cavity of the receiving antenna is composed of a number of metal through holes between the upper surface of the upper dielectric substrate and the second metal plate. The ring-shaped metasurface structure, the feed slot and the strip feeder are completely enclosed. While suppressing the energy leakage of the strip feeder, it avoids the difficult-to-achieve setting of blind holes and buried holes, and realizes the independence of the receiving antenna itself.

A self-shielding millimeter-wave metasurface radar transmitting antenna, comprising an upper dielectric substrate 1, a first metal plate 2, a prepreg 3, a lower dielectric substrate 4 and a second metal plate 5 from top to bottom, the upper dielectric substrate 1 An emission metasurface structure 9 is arranged on the upper surface, an emission feeding slit 11 is etched on the first metal floor 2, an emission strip feeder 13 is arranged between the prepreg 3 and the lower dielectric substrate 4, and on the upper dielectric substrate 1 Between the surface and the second metal plate 5, metal through holes are arranged around the emitting metasurface structure 9, the emitting feed slot 11 and the emitting strip feeder 13 to form a self-shielding cavity 15 of the emitting antenna.

Further, the emitting metasurface structure described in this embodiment includes M×N emitting ring-shaped patch units arranged in a centrally symmetrical period, each emitting ring-shaped patch unit is provided with a square patch, and the emitting ring-shaped patch unit is preferably a square patch. Ring patch, the ring design increases the surface current path of the metasurface structure, effectively reduces the size of the metasurface structure, and the square patch effectively improves the impedance characteristics of the antenna.

The metal patch is not limited to a square shape, and may also be a parallelogram, trapezoid, rhombus, etc. that have been miniaturized.

Further, the transmitting feeding slot 11 is an "I"-shaped feeding slot, which is arranged on the first metal floor to excite the transmitting metasurface structure 9 to generate linearly polarized radiation; the transmitting feeding slot is one, and the feeding slot The shape is not limited, it can be I-shaped, H-shaped, U-shaped or horizontal seam, etc. In Embodiment 1, an asymmetric "I"-shaped feeding slot is etched at a position deviated from the center of the emitting metasurface structure 9 .

Further, the transmitting feeder is in the form of a stripline, the feeding point is a grounded coplanar waveguide arranged in the center of the second metal plate, and the transition from the grounded coplanar waveguide to the stripline feeder is made through a metal via hole, and Use straight lines, arcs or 45-degree angles to route lines perpendicular to the feed slot and excite them; the strip feeder is provided with two quarter-wavelength fan-shaped open-circuit stubs, which effectively suppress the third and fifth harmonic energy .

Further, two rows of metal vias 18 connecting the upper surface of the upper dielectric plate and the second metal plate are arranged in the square ring patch. The metal vias are arranged on the upper and lower sides of the two square patches, which reduces the size of the transmitting antenna. The size of the self-shielding cavity further realizes the third harmonic energy pair suppression.

The I-shaped feeding slit is etched at a position deviated from the center of the square ring and the square patch to further suppress the fifth harmonic energy pair.

The transmitting antenna of the embodiment of the present invention adopts the simple processing technology of four-layer board PCB. The self-shielding cavity of the transmitting antenna is composed of a number of metal through holes between the upper surface of the upper dielectric substrate and the second metal plate. The transmitting metasurface structure, transmitting The feeding slot and the transmitting strip feeder are completely enclosed, while suppressing the energy leakage of the transmitting strip feeder, avoiding the difficult-to-achieve setting of blind holes and buried holes, and realizing the independence of the transmitting antenna itself.

Self-shielded millimeter-wave radar transceiver integrated antenna, the specific dimensions are as follows:

For a self-shielded receiving antenna, the height _H1 of the annular metasurface radiation patch is 0.787 mm, the square ring patch width rw1 of the receiving antenna is 2.2 mm, the length rl1 is 1.65 mm, the ring width rw3 is 0.15 mm, and rw4 is 0.175 mm mm, the edge distance rg1 of the square ring unit is 0.1mm; the length rl2 and width rw2 of the self-shielding cavity 14 of the receiving antenna are 3.9mm and 2.7mm respectively, the diameter of the metal via hole is 0.15mm, and the center distance of the metal via hole is 0.3mm mm; the length rl3 of the H-shaped feeding slot etched on the first layer metal plate 2 is 2.2mm, the rl4 is 1.3mm, and the slot width rg2 is 0.2mm; the step impedance transformation width of the single-ended strip feeder rw5 is 0.19mm, rw6 is 0.4mm, rw7 is 0.1mm, rw8 is 0.18mm, length rl5 is 0.6mm, and rl6 is 0.34mm.

For the self-shielded transmitting antenna 7, the height _H1 of the ring and square metasurface radiation patch is 0.787mm, wherein the length tl1 of the square ring patch is 1.66mm, the width tw1 is 2.17mm, and the ring widths tw4 and tw5 are 0.1mm , the edge spacing tg1 of the square ring unit is 0.2mm, the length tl2 of the square patch in the ring is 1mm, the width tw2 is 1.77mm, the edge spacing tg2 of the square patch and the ring patch is 0.1mm; the self-shielding cavity of the transmitting antenna The length tl3 and width tw3 are 3.9mm and 2.7mm respectively, the diameter of the metal via hole is 0.15mm, and the center distance of the metal via hole is 0.3mm; the I-shaped feed slot 11 etched on the first layer metal plate 2 The length tl4 is 1.57mm, tl5 is 1.37mm, tl6 is 0.8mm, the gap width tg6 is 0.1mm, and the distance between two rows of metal vias is 2.95mm; the step impedance transformation width tw6 of the strip feeder is 0.1mm, and tw7 is 0.23mm, open branch length tl8, tl9 were 0.46mm, 0.29mm.

For the decoupling structure 16 that suppresses the energy coupling of the transceiver antenna, the length el of the periodically arranged metal patches is 2.47mm, the width ew is 0.2mm, the edge spacing eg1 and eg2 is 0.1mm, and the diameter of the ground metal via hole is 0.1mm.

As shown in Figure 4, the self-shielded millimeter-wave metasurface radar transceiver antenna, the working frequency band is: 24-26GHz, the reflection coefficient of all ports in the band is lower than -14dB, and the isolation between the single port of the receiving antenna and the differential port of the transmitting antenna in the band Greater than 25dB, it ensures high transceiver isolation while having a compact structure. As shown in Figure 8, the gains of the self-shielded receiving antenna and the self-shielded transmitting antenna are 5.3-5.6dBi and 5.0-5.5dBi respectively; as can be seen from Figures 5 and 6, the self-shielded receiving antenna and the self-shielded The E-plane pattern of the shielded transmitting antenna has good symmetry; as shown in Figure 7 and Figure 8, the energy suppression of the transmitting antenna at the third harmonic and the fifth harmonic is greater than 32.5dB and 12dB, respectively.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the embodiment, and any other changes, modifications, substitutions and combinations made without departing from the spirit and principle of the present invention , simplification, all should be equivalent replacement methods, and are all included in the protection scope of the present invention.

Claims (13)

1. The millimeter wave super-surface radar receiving antenna is characterized by sequentially comprising an upper medium substrate, a first metal plate, a prepreg, a lower medium substrate and a second metal plate from top to bottom, wherein the upper surface of the upper medium substrate is provided with a receiving super-surface structure, a receiving feed gap is etched on the first metal floor, a receiving strip feeder is arranged between the prepreg and the lower medium substrate, and a metal through hole is arranged between the upper surface of the upper medium substrate and the second metal plate around the receiving super-surface structure, the receiving feed gap and the receiving strip feeder to form a self-shielding cavity of the receiving antenna.

2. The millimeter wave super-surface radar receiving antenna according to claim 1, wherein the receiving super-surface structure is constituted by m×n receiving annular patch units arranged in a central symmetrical cycle.

3. The millimeter wave super-surface radar receiving antenna of claim 1, wherein said receiving feed slot is an H-slot, excited by a receiving strip feed, further exciting an upper receiving super-surface structure to produce linearly polarized radiation.

4. A millimeter wave super surface radar receiving antenna according to any one of claims 1-3, characterised in that said receiving strip feed is a single ended strip feed.

5. The millimeter wave super-surface radar transmitting antenna is characterized by sequentially comprising an upper medium substrate, a first metal plate, a prepreg, a lower medium substrate and a second metal plate from top to bottom, wherein the upper surface of the upper medium substrate is provided with a transmitting super-surface structure, a transmitting feed gap is etched on the first metal floor, a transmitting strip feeder is arranged between the prepreg and the lower medium substrate, the transmitting strip feeder further comprises an open circuit branch, and a metal through hole is arranged between the upper surface of the upper medium substrate and the second metal plate around the transmitting super-surface structure, the transmitting feed gap and the transmitting strip feeder to form a self-shielding cavity of the transmitting antenna.

6. The millimeter wave super-surface radar transmitting antenna according to claim 5, wherein said transmitting super-surface structure comprises M x N transmitting annular patch units arranged in a central symmetry period, and each transmitting annular patch unit is provided with a square patch therein.

7. The millimeter wave super-surface radar transmitting antenna of claim 5, wherein said transmitting feed slot is an i-slot, excited by said transmitting strip feed line, further exciting the transmitting super-surface structure to produce linearly polarized radiation.

8. The millimeter wave super surface radar transmitting antenna according to claim 5, wherein said transmitting strip feed line is a double ended differential feed line.

9. The millimeter wave super-surface radar transmitting antenna according to claim 5, characterized in that said open stubs suppress three and five harmonic energies for two quarter wavelength sectors.

10. The millimeter wave super surface radar transmitting antenna according to claim 6, wherein one side of said square patch is provided with a row of metal vias and is located in a transmitting annular patch unit.

11. The millimeter wave super-surface radar transmitting antenna according to claim 7, wherein the i-shaped slot is offset from a central position of the transmitting super-surface structure, so as to suppress five times of harmonic energy.

12. The millimeter wave super-surface radar receiving and transmitting integrated antenna is characterized by comprising a receiving antenna and a transmitting antenna, wherein the receiving antenna and the transmitting antenna are symmetrically arranged on two sides of the antenna, a central connecting line of the receiving antenna and the transmitting antenna is perpendicular to the polarization direction of the antenna, a decoupling structure for inhibiting energy coupling of the receiving and transmitting antenna is arranged at the middle position of the receiving antenna and the transmitting antenna, a feeding point is concentrated at the central position of the bottom of the antenna, the receiving antenna is specifically the millimeter wave super-surface radar receiving antenna according to any one of claims 1-4, and the transmitting antenna is specifically the millimeter wave super-surface radar transmitting antenna according to any one of claims 5-11.

13. The integrated transceiver antenna of claim 12, wherein the decoupling structure comprises a periodic arrangement of rectangular metal strips, each rectangular metal strip having a ground metal via disposed therein.

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