阅读说明：本技术 一种全集成宽角度扫描的圆极化折叠反射阵列天线 (Circular polarization folding reflection array antenna of full integrated wide angle scanning ) 是由 张云华 余振宇 何思远 朱国强 于 2020-12-18 设计创作，主要内容包括：本发明涉及一种全集成宽角度扫描的圆极化折叠反射阵列天线,包括极化栅阵列,其特征在于：设置主反射器和极化转换器,极化栅阵列安装在主反射器上方,极化转换器安装在极化栅阵列上方；所述主反射器中在单层的介质板上集成设置多个基片集成背腔缝隙天线和多个具有移相功能的移相贴片单元,所述极化转换器通过在三层介质板中分别印制回折线形状的金属条带形成,其中第一层与第三层的回折线具有相同的尺寸。本发明提供的多波束折叠反射阵列天线具有波束覆盖角度大,整体剖面低,圆极化辐射的特点,能够应用于5G通讯,雷达成像,以及目标探测等领域。(The invention relates to a full-integrated wide-angle scanning circularly polarized folded reflective array antenna, which comprises a polarized grid array and is characterized in that: arranging a main reflector and a polarization converter, wherein a polarization grid array is arranged above the main reflector, and the polarization converter is arranged above the polarization grid array; the main reflector is provided with a plurality of substrate integrated cavity-backed slot antennas and a plurality of phase-shifting patch units with a phase-shifting function on a single-layer dielectric plate in an integrated mode, the polarization converter is formed by respectively printing metal strips with zigzag line shapes on three layers of dielectric plates, and the zigzag lines of a first layer and a third layer have the same size. The multi-beam folding reflection array antenna provided by the invention has the characteristics of large beam coverage angle, low overall section and circularly polarized radiation, and can be applied to the fields of 5G communication, radar imaging, target detection and the like.)

1. A circular polarization folding reflection array antenna of full integrated wide angle scanning, includes the polarization grid array, its characterized in that: arranging a main reflector and a polarization converter, wherein a polarization grid array is arranged above the main reflector, and the polarization converter is arranged above the polarization grid array; the main reflector is provided with a plurality of substrate integrated cavity-backed slot antennas and a plurality of phase-shifting patch units with a phase-shifting function on a single-layer dielectric plate in an integrated mode, the polarization converter is formed by respectively printing metal strips with zigzag line shapes on three layers of dielectric plates, and the zigzag lines of a first layer and a third layer have the same size.

2. The fully integrated wide angle scanning circularly polarized folded reflective array antenna of claim 1, wherein: and a support column is arranged, the polarization grid array is fixed above the main reflector through the support column, and the polarization converter is fixed above the polarization grid array through the support column.

3. The fully integrated wide angle scanning circularly polarized folded reflective array antenna of claim 1, wherein: the substrate integrated back cavity slot antenna comprises a metal frame and a square metal patch printed on the upper metal surface of a dielectric plate, a plurality of metalized through holes are filled in a gap between the metal frame and the square metal patch to form a substrate integrated waveguide structure, a coaxial probe on the bottom layer of the dielectric plate feeds and transmits TEM waves to the square metal patch, and the TEM waves are converted into TE through the substrate integrated waveguide₁₀And the wave radiates outwards through the gap between the metal frame and the square metal patch.

4. The fully integrated wide angle scanning circularly polarized folded reflective array antenna of claim 3, wherein: seven substrate integrated back cavity slot antennas are arranged, and the distance D of each substrate integrated back cavity slot antenna 2_f＝12.7mm。

5. The fully integrated wide angle scanning circularly polarized folded reflectarray antenna of claim 1, or 2, or 3, or 4, wherein: the single-layer dielectric plate in the main reflector adopts a Rogers 5880 dielectric plate.

6. The fully integrated wide angle scanning circularly polarized folded reflectarray antenna of claim 1, or 2, or 3, or 4, wherein: the polarization converter is a circular polarization converter of a fold-back line type and is formed by respectively printing fold-back line structures on three layers of dielectric plates, wherein the width w1 of the fold-back lines of the first layer and the third layer is 0.2mm, the width w2 of the fold-back lines of the middle layer is 0.46mm, and the three layers of the fold-back line structures are arranged at equal intervals.

7. The fully integrated wide angle scanning circularly polarized folded reflective array antenna of claim 6, wherein: and the three dielectric plates are all FR-4 dielectric plates.

Technical Field

The invention relates to a reflective array antenna, in particular to a fully-integrated wide-angle scanning circularly polarized folded reflective array antenna.

Background

Due to the fact that the millimeter wave band has wider spectrum bandwidth and narrower wave beams, the millimeter wave band has great application potential in the fields of military radars, remote sensing detection, satellite communication and the like. Meanwhile, millimeter wave frequency band business has received much attention in 5G mobile communication. Compared with conventional microwave communication, millimeter wave communication has larger transmission loss. The microstrip reflection array antenna, as a novel high-gain antenna, can well overcome the problem. Folded reflectarray antennas were proposed by Menzel and Pilz in 1998 as a new type of reflectarray antenna. By introducing the reflecting plate and the polarization grating array to carry out beam convergence and polarization conversion, the folded reflection array antenna can effectively reduce the whole section of the antenna and eliminate feed source shielding at the same time. In recent years, the folded reflect array antenna has been greatly developed and widely used in the fields of dual-mode communication, beamforming, and broadband antennas.

However, achieving wide-angle beam scanning is a major challenge in the field of folded reflect column antennas. Many folded reflect array antennas with beam scanning function have been proposed, which can be summarized as: mechanical beam scanning, multi-beam scanning, and electrical beam scanning. For mechanical beam scanning, the scanning angle is small, and an additional mechanical control structure is needed; for multi-beam scanning, multiple array antennas are often required to cover a wide scanning range; for electronically controlled beam scanning, a control circuit with complex design and high cost is required, and meanwhile, the loss is high. Low profile feed antennas that are easy to integrate are another challenge in the field of folded reflectarray antennas. The traditional folded reflection array antenna usually needs to adopt a horn antenna for feeding, but the horn antenna is a three-dimensional antenna with large volume and high section, and is difficult to integrate with an active circuit. At present, researchers have proposed that a microstrip array antenna is used as a feed antenna for feeding, however, the microstrip feed antenna proposed at present needs a multilayer dielectric substrate, which greatly increases the manufacturing cost, and meanwhile, strong mutual coupling exists between the microstrip antennas, so that the integrated design of a plurality of feed sources in a single dielectric plate cannot be realized. Meanwhile, for the conventional folded reflection array antenna, due to the introduction of the single-polarization grid array, the radiated beam of the antenna can only be a linearly polarized electromagnetic wave. Therefore, circularly polarized radiation is another major problem to be solved in the field of folded reflective array antennas.

Based on the above background, a fully integrated wide-angle scanning circular polarization folded reflective array antenna is provided, which is a great problem to be solved in the field.

Disclosure of Invention

The invention mainly solves the technical problems existing in the prior art; the circularly polarized folded reflective array antenna with the fully integrated wide-angle scanning function is provided, and is used for solving the problems that the existing folded reflective array antenna is difficult to realize wide-angle coverage, high in overall section and single in polarization form.

The technical problem of the invention is mainly solved by the following technical scheme:

a circular polarization folding reflection array antenna with fully integrated wide-angle scanning comprises a polarization grid array, a main reflector and a polarization converter, wherein the polarization grid array is arranged above the main reflector, and the polarization converter is arranged above the polarization grid array; the main reflector is provided with a plurality of substrate integrated cavity-backed slot antennas and a plurality of phase-shifting patch units with a phase-shifting function on a single-layer dielectric plate in an integrated mode, the polarization converter is formed by respectively printing metal strips with zigzag line shapes on three layers of dielectric plates, and the zigzag lines of a first layer and a third layer have the same size.

And moreover, a supporting column is arranged, the polarization grid array is fixed above the main reflector through the supporting column, and the polarization converter is fixed above the polarization grid array through the supporting column.

The substrate integrated back cavity slot antenna comprises a dielectric plate, wherein a metal frame and a square metal patch are printed on the upper metal surface of the dielectric plate, a plurality of metalized through holes are filled in a gap between the metal frame and the square metal patch to form a substrate integrated waveguide structure, a coaxial probe at the bottom layer of the dielectric plate feeds and transmits TEM waves to the square metal patch, and the TEM waves are converted into TEM waves through the substrate integrated waveguideTE₁₀And the wave radiates outwards through the gap between the metal frame and the square metal patch.

Furthermore, seven substrate-integrated cavity-backed slot antennas are provided, the distance D of each substrate-integrated cavity-backed slot antenna 2_f＝12.7mm。

Moreover, the single-layer dielectric plate in the main reflector adopts a Rogers 5880 dielectric plate.

The polarization converter is a circular polarization converter of a meander line type, and is formed by printing meander line structures on three dielectric plates, wherein the width w1 of the first layer and the third layer of meander line is 0.2mm, the width w2 of the middle layer of meander line is 0.46mm, and the three layers of meander line structures are arranged at equal intervals.

And the three dielectric slabs are all FR-4 dielectric slabs.

The multi-beam folding reflection array antenna provided by the invention has the characteristics of large beam coverage angle, low overall section and circularly polarized radiation, and can be applied to the fields of 5G communication, radar imaging, target detection and the like.

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

1) the novel folding reflection array antenna disclosed by the invention can simultaneously radiate a plurality of high-gain circularly polarized wave beams in a wide angle range, and can be applied to the fields of military radars, information countermeasure, satellite communication and the like;

2) according to the novel folding reflection array antenna disclosed by the invention, the plurality of substrate integrated back cavity slot antennas and the metal phase-shifting patch units are integrated on the single-layer dielectric plate, so that the section of the folding reflection array antenna can be effectively reduced, the design complexity of the reflection array antenna is simplified, and the processing cost of the folding reflection array antenna is reduced;

3) the novel folding reflection array antenna disclosed by the invention overcomes the defect that the traditional folding reflection array antenna can only radiate single linear polarization, can realize circular polarization radiation and greatly expands the application range of the novel folding reflection array antenna;

4) the novel folding reflection array antenna disclosed by the invention adopts coaxial probe type feed, does not need any conversion structure, and can be conveniently connected with an active circuit.

Drawings

Fig. 1 is a schematic structural diagram of a fully integrated wide-angle scanning circular polarization folded reflective array antenna in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a main reflector in an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a substrate integrated cavity-backed slot antenna according to an embodiment of the present invention;

FIG. 4 shows a reflection coefficient simulation result of a substrate integrated cavity backed slot antenna according to an embodiment of the present invention;

FIG. 5 shows simulation results of the directional patterns of the substrate integrated cavity-backed slot antenna according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a polarization transformer in an embodiment of the present invention;

FIG. 7 is a simulation result of the transmittance of the polarization transformer under different angles of plane wave illumination in the embodiment of the present invention;

FIG. 8 is a simulation result of the phase difference of the transmission of the polarization transformer under different angles of plane wave irradiation in the embodiment of the present invention;

fig. 9 is a simulation result of reflection coefficients of ports of the multi-beam circular polarization folded reflective array antenna according to the embodiment of the present invention;

FIG. 10 is a simulation result of cross-coupling coefficients of ports of a fully integrated wide-angle scanning circularly polarized folded reflective array antenna according to an embodiment of the present invention;

FIG. 11 is a simulation result of the gain pattern and axial ratio pattern of the fully integrated wide-angle scanning circularly polarized folded reflectarray antenna at-27 ° in the embodiment of the present invention;

FIG. 12 is a simulation result of the gain pattern and axial ratio pattern of the fully integrated wide-angle scanning circularly polarized folded reflectarray antenna at-18 ° in the embodiment of the present invention;

FIG. 13 is a simulation result of the gain pattern and axial ratio pattern of the fully integrated wide-angle scanning circularly polarized folded reflectarray antenna at-9 ° in the embodiment of the present invention;

fig. 14 is a simulation result of the gain directional diagram and the axial ratio directional diagram of the fully integrated wide-angle scanning circularly polarized folded reflective array antenna at 0 ° in the embodiment of the present invention;

fig. 15 is a simulation result of the gain directional diagram and the axial ratio directional diagram of the fully integrated wide-angle scanning circularly polarized folded reflective array antenna at 9 ° in the embodiment of the present invention;

fig. 16 is a simulation result of the gain directional diagram and the axial ratio directional diagram of the fully integrated wide-angle scanning circularly polarized folded reflective array antenna at 18 ° in the embodiment of the present invention;

fig. 17 is a simulation result of the gain directional diagram and the axial ratio directional diagram of the fully integrated wide-angle scanning circularly polarized folded reflective array antenna at 27 ° in the embodiment of the present invention;

fig. 18 is a schematic port diagram of a fully integrated wide-angle scanning circular polarization folded reflective array antenna in an embodiment of the present invention.

Detailed Description

The technical solution of the present invention will be further described with reference to the following detailed description and accompanying drawings.

The embodiment discloses a fully-integrated wide-angle scanning circularly polarized folded reflective array antenna, which comprises a main reflector 1, a plurality of substrate integrated back cavity slot antennas 2, a polarization grating array 3, a polarization converter 4, support columns 5 and a phase-shifting patch unit 6, as shown in fig. 1. The support column 5 preferably adopts a Teflon-like plastic structure, the phase-shifting patch unit 6 adopts a metal material, and the metal material can be selected according to the radiation performance requirement of the folding reflective array antenna during specific implementation.

A polarization grid array 3 is mounted above the main reflector 1 and a polarization transformer 4 is mounted above the polarization grid array 3. Preferably, four support posts 5 may be provided, the polarization grid array 3 being fixed above the main reflector 1 by the support posts 5, and the polarization transformer 4 being also fixed above the polarization grid array 3 by the support posts 5.

In the embodiment, a plurality of substrate integrated back cavity slot antennas 2 and a plurality of phase shift patch units 6 with a phase shift function arranged in a main reflector 1 are integrated on the upper surface of a single-layer dielectric plate 9, a metal bottom plate is arranged on the lower surface of the dielectric plate 9 to reflect electromagnetic waves, and the plurality of substrate integrated back cavity slot antennas 2 are preferably arranged at equal intervals. The phase-shift patch unit 6 is generally a metal patch with a rectangular structure.

The polarization grid array 3 is composed of a plurality of metal strips 8 with the same shape and the same interval, and is preferably formed by printing rectangular metal strips with the same size and the same interval on a single-layer dielectric plate.

The polarization converter 4 is formed by printing metal strips in a zigzag shape in three dielectric sheets, respectively, wherein the zigzag lines of the first and third layers have the same size.

Each substrate integrated cavity-backed slot antenna controls a radiation beam, and the switching of the beams in different radiation directions can be realized by selecting different substrate integrated cavity-backed antennas for feeding.

The invention can adjust the phase by changing the size of the metal patch without a complex control circuit. The principle of the preferred arrangement of the substrate integrated cavity-backed slot antenna 2 of the embodiment is explained as follows,

the M multiplied by N phase-shifting patch units 6 are arranged on the dielectric plate 9 at equal intervals, and for a beam scanning reflective array antenna, the phase required by each metal phase-shifting patch unit on the aperture surfaceCan be calculated by the following formula:

wherein k is₀Representing wave number in vacuum, i is used to identify the ith designed beam, (x)_mn,y_mn) Represents the center coordinate theta of the mth row and nth column phase-shift patch unit⁽ⁱ⁾Representing the elevation angle of the ith beam,denotes the azimuth angle, Δ φ, of the ith beam⁽ⁱ⁾Reference phase representing ith design beamThe number of bits is,the distance between the feed phase center and the nth column phase-shifting patch unit of the mth row is shown, wherein M is 1,2, … M, and N is 1,2, … N. To simplify the design, a symmetrical three-beam optimization scheme is employed. The three designed beam directions are respectivelyAt the same time, the first beam and the third beam have the same reference phase Δ φ⁽¹⁾＝Δφ⁽³⁾. Thus, the required phase compensation can be simplified to

For a designed beam, the overall phase error for each phase-shifted patch element can be expressed as

WhereinThe phase position realized by the mth row and nth column of phase-shifting patch units, L is the size of the phase-shifting patch units, and the weight factor is calculated according to the antenna array theoryCan be expressed as

WhereinAndradiation patterns of feed antenna and phase-shifting patch element, respectively, q_fAs a feed antenna pattern factor, q_eFor phase-shifting patch element pattern factors, θ_fIs the observation angle, theta, of the feed antenna pattern_eIs the observation angle of the directional diagram of the phase-shifted patch element. And the BDF can be expressed as the feed source bias factor

Where θ is the designed beam pointing angle and α represents the offset angle of the feed antenna. As can be seen from equation (1), the required phase distribution for the ith beam can be determined by the spatial distanceAnd a reference phase delta phi⁽ⁱ⁾And (4) calculating. And spatial distanceIs about a feed bias factor BDF⁽ⁱ⁾Can be expressed as a functional relationship

Where F is the focal length, in this example F is 99 mm. Thus, an objective function is established with respect to the minimum weighted phase error, which can be expressed as

In the embodiment, formula (7) is optimized through a particle swarm optimization, a circular polarization folded reflective array antenna capable of covering +/-27-degree full-integration wide-angle scanning is designed, and finally, the feed source bias factor and the reference phase obtained through optimization are BDF⁽¹⁾＝BDF⁽³⁾＝0.94，BDF⁽²⁾＝1，Δφ⁽¹⁾＝Δφ⁽³⁾＝306°，Δφ⁽²⁾Calculating the size of each metal phase-shifting patch unit according to the formula (1) at 6 degrees, integrally designing seven substrate integrated cavity-backed slot antennas 2 and a plurality of phase-shifting patch units 6 in the main reflector 1, and calculating the distance D of each substrate integrated cavity-backed slot antenna 2 according to the formula (6)_fDifferent wavefront phases are constructed to form differently directed beams, 12.7mm, and the final constructed main reflector is shown in fig. 2. Without loss of generality, the substrate integrated back cavity slot antenna integrated in the main reflector is not limited to seven, the beam coverage can be enlarged by increasing the number of the substrate integrated back cavity slot antennas, and the beam direction can be adjusted by adjusting the distance between the substrate integrated back cavity slot antennas.

As shown in fig. 1, a support column 5 is used to support the main reflector 1 and the polarization grid array 3, so that the distance between the main reflector 1 and the polarization grid array 3 is half of the focal length, and the polarization converter 4 is fixed above the polarization grid array 3 through the support column 5. The polarization grid array 3 is composed of a plurality of metal strips 7 with the same shape and the same distance.

As shown in fig. 3, a metal frame 10 and a square metal patch 11 are printed on an upper metal surface of a dielectric plate 9, a plurality of metallized via holes 12 are filled in a gap formed between the metal frame 10 and the square metal patch 11 to form a substrate integrated waveguide structure, a coaxial probe 13 on a bottom layer of the dielectric plate 9 feeds the square metal patch 11 to transmit TEM waves (transverse electromagnetic waves), and the transverse electromagnetic waves are converted into TE waves through the substrate integrated waveguide₁₀A wave (10 mode of transverse electric wave) is radiated outward through the gap between the metal frame 10 and the square metal patch 11.

Preferably, the metal frame 10 is a metal square ring arranged on the outer edge of the dielectric plate 9, the square metal patches 11 are arranged in the middle of the dielectric plate 9, and the metalized through holes 12 are uniformly distributed and arranged between the upper metal surface and the lower metal surface of the dielectric plate 9 in the gap formed between the metal frame 10 and the square metal patches 11.

In specific implementation, the dielectric plate 9 is preferably a single layer rogowski 5880 dielectric plate.

The reflection coefficient of the substrate integrated cavity backed slot antenna and the pattern at 26.5GHz are shown in fig. 4 and 5. As can be seen from FIG. 4, the reflection coefficient of the antenna can be lower than-10 dB at 26.5GHz, and the E-plane and H-plane patterns of the antenna show good symmetry in the range of-60 degrees to 60 degrees as can be seen from FIG. 5, and the maximum gain reaches 7.2 dBi. Here, the E plane is a plane formed by an electric field and a beam direction, and the H plane is a plane formed by a magnetic field and a beam direction.

The polarization converter 4 is a circular polarization converter of a fold-back line type, as shown in fig. 6, and is formed by printing fold-back line structures 8 on three layers of FR-4 dielectric boards, wherein the first layer and the third layer are preferably set to have the same size, the fold-back line structure with a fold-back line width w1 of 0.2mm and the middle layer is slightly larger in size, the fold-back line structure with a fold-back line width w2 of 0.46mm ensures that the polarization converter 4 can realize conversion from linear polarization to circular polarization in a wide angle range, and the three layers of fold-back line structures are arranged at equal intervals. The polarization converter 4 has the transmission coefficient ratio and the transmission phase difference at the time of incidence of the TE wave and the TM wave as shown in fig. 7 and 8. As can be seen from FIG. 7, the transmission coefficients are all greater than 0.9 in the range of 22GHz to 30GHz for different incident angles, and as can be seen from FIG. 8, the transmission phase difference can be maintained between 90 ° and 100 ° at 26.5 GHz.

Referring to fig. 18, the circular polarization folded reflection array antenna is provided with ports 1 to 7, which correspond to the coaxial probes 13 of the 7 antennas, respectively. Fig. 9 shows reflection coefficients of port 1 to port 7 of the fully integrated wide-angle scanning circular polarization folded reflective array antenna, fig. 10 shows mutual coupling coefficients of port 1 and port 7 of the fully integrated wide-angle scanning circular polarization folded reflective array antenna, and fig. 11 to 17 show normalized directional patterns and axial ratio directional patterns of the fully integrated wide-angle scanning circular polarization folded reflective array antenna at different scanning angles.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.