CN108666743A - Orthogonal Polarization Planar Array Antenna Design Using Cross-polarization Suppression Method - Google Patents

Abstract

The invention discloses a kind of cross polarization planar array antennas designed using cross polarization suppressing method.Antenna is mainly arranged and is formed by connecting by basic array, basic array with 4 × 4 arrays and is formed by connecting by radiating element, there are two orthogonal feed ports for each radiating element tool, it is connected by feeding network between each radiating element between each basic array and in basic array, each radiating element and its orthogonal feed port in each basic array are arranged with horizontal or vertical mirror image or arranged with horizontal and vertical mirror image simultaneously.A variety of central symmetry arrays such as circular array, square array and the rectangular array that the method used in the present invention is suitable for being operated under linear polarization and circular polarization pattern, it can be widely applied to work in the planar array antenna of cross polarization, on especially electric wide aperture array.

Description

Orthogonal Polarization Planar Array Antenna Design Using Cross-polarization Suppression Method

technical field

The invention relates to a planar array antenna, in particular to an orthogonally polarized planar array antenna designed by adopting a cross-polarization suppression method, and simultaneously verifies the feasibility.

Background technique

Since orthogonally polarized planar array antennas allow different information to be transmitted within the same bandwidth, they currently play an important role in bandwidth-sensitive satellite communications. Using orthogonally polarized planar array antennas, the effective bandwidth of the antenna can be doubled. However, in this type of antenna, whether it is a circular polarization antenna or a linear polarization antenna, the requirements for cross polarization are very high. With the rapid development of mobile communication antenna technology, in order to avoid potential interference in satellite communication, it is very important to suppress cross-polarization technology. At the same time, in order to install a streamlined radome on the satellite antenna, it is necessary to design a flat low-profile antenna to meet the requirements, which urgently requires new technologies for cross-polarization suppression.

At present, papers have proposed a variety of methods for suppressing cross-polarization of multi-polarized antennas. One method is to reduce the cross-polarization of array elements by adjusting and changing the structure of the radiating element, and then reduce the cross-polarization of the array structure. The cross-mode coupler can effectively reduce the cross-polarization; another method is to make the adjacent elements in the antenna array mirror symmetrical and apply the corresponding feed phase. The cross-polarization components generated by the ports of adjacent units suppress or cancel each other, although the cross-polarization performance will be greatly improved, but when designing a large array, since each array element is symmetrical to the adjacent unit, each symmetrical feed Both may require phase inversion, so the design of the feed network is more complicated than the proposed method. For example, the inversion of the microstrip feed means that the electrical length of the microstrip line increases, resulting in a longer space for the microstrip line or even a broken line, because factors such as limited space may make array design more difficult.

Contents of the invention

In order to solve the problems existing in the background technology, the present invention discloses a method for suppressing cross polarization of an orthogonally polarized planar array antenna.

The technical scheme adopted in the present invention is:

The antenna is designed by a proposed cross-polarization suppression method, and is an antenna structure that is mirror-symmetrical in the horizontal or vertical direction, or mirror-symmetrical in both the horizontal and vertical directions.

The antenna is mainly composed of basic arrays arranged and connected. The basic array is formed by connecting radiation units in a 4×4 array. Each radiation unit has two orthogonal feed ports. Between each basic array and the basic Each radiating unit in the array is connected through a feed network, and each radiating unit in each basic array and its orthogonal feeding port are arranged in a horizontal or vertical mirror-symmetrical manner or simultaneously mirrored horizontally and vertically Arranged symmetrically.

The antennas are mainly composed of a top layer, a bottom layer and a stratum between the top layer and the bottom layer. The surface of the top layer is the radiating surface, the surface of the bottom layer is the back, and the radiating surface and the back are evenly distributed with feed networks.

When arranged in the horizontal mirror-symmetrical manner, the radiating surface adopts the equal-amplitude in-phase feed network, and the back adopts the equal-amplitude anti-phase feed network; when arranged in the vertical mirror-symmetrical manner, the radiating surface adopts the equal-amplitude feed network In the anti-phase feed network, the same-amplitude in-phase feed network is used on the back; when the horizontal and vertical simultaneous mirror-symmetrical arrangements are arranged, both the radiation surface and the back adopt an equal-amplitude anti-phase feed network.

The specific layout structure of the equal-amplitude and in-phase feed network is a multi-stage microstrip power-dividing network such as a Wilkinson power divider, and the number of stages of the power-dividing network is half of the total number of antenna radiation units.

The specific layout structure of the equal-amplitude anti-phase feed network is different from that of the equal-amplitude in-phase feed network in that the difference in the length of the microstrip line at the two output ends of the first-stage power division is 180°.

The feeding network on the radiating surface and the rear side respectively correspond to two orthogonal polarizations of the antenna.

The formation material is pure copper, and the top layer and the bottom layer are both substrates made of FR4.

The invention is an orthogonally polarized planar array antenna designed by adopting a cross-polarization suppression method.

In the present invention, the feeding network can be integrated and designed on the orthogonally polarized planar array antenna, or the antenna radiating elements can be fed separately by independent feeding devices. For the basic array with mirror symmetry, its affiliated feed network is also mirror-symmetric; for the basic array with mutual mirror symmetry, the input port of its affiliated feed network needs to be fed by a feed network with equal-amplitude and anti-phase output.

The present invention regards the entire antenna aperture as composed of even or odd identical basic arrays that are fed through the same-phase feed network, so that adjacent basic arrays are mirror images of each other.

The basic array of antennas is mirror-symmetrically processed to form an antenna structure that is horizontally or vertically mirror-symmetrical, or horizontally and vertically mirror-symmetrical at the same time, so that the antenna can work in an orthogonal polarization mode.

In the present invention, firstly, the basic array is obtained through the mirror symmetry method through the primary symmetry or the double symmetry method to obtain the orthogonally polarized planar array antenna with suppressed cross polarization. Secondly, the corresponding constant-amplitude in-phase and constant-amplitude anti-phase feed networks are designed for the basic array, so that it meets the requirements of the mirror-symmetry basic array for feeding between the feed ports corresponding to each position. And the specific cross-polarization isolation is obtained by making a difference between the cross-polarization level and the main polarization level that is specifically simulated or measured.

The present invention can solve the problems existing in the existing cross-polarization suppression methods, and has the beneficial effects of:

1. There is no need to design a more complex radiation unit structure to meet the cross-polarization index, and the cross-polarization tolerance of the unit is greatly improved.

2. Compared with the method in which adjacent radiating elements are symmetrical, the near-field coupling effect is slightly less affected in the tightly coupled array antenna.

3. The adjustment of the basic array level makes the feed network only need to consider the anti-phase structure design when the power is allocated for the first time. Compared with the symmetrical method of adjacent radiation units, under the premise of ensuring the cross-polarization isolation index The complexity of the antenna array is greatly reduced.

4. The applicable antenna polarization forms are wider, and the shape of the basic array is not limited to square or rectangle.

Description of drawings

Figure 1 is a schematic diagram of the implementation process of the cross-polarization suppression method for orthogonally polarized planar array antennas. In the figure: (a), (b), and (c) respectively represent three orthogonally polarized planar array antennas, and the outer boxes in each sub-figure represent the basic array, 1, 2, 3, 4, 5, 6, 7 and 8 both represent the radiation unit of the planar array antenna. In the figure, the solid triangle represents the 0° in-phase feed port, and the solid square represents the 180° π-phase feed port.

Accompanying drawing 2 is the diagram of theoretical calculation results of the horizontal polarization cross-polarization isolation of the three antennas (a), (b) and (c) corresponding to Fig. 1 .

Figure 3 is an evolution diagram of all possible structures of an orthogonally polarized planar array antenna designed using a cross-polarization suppression method.

Accompanying drawing 4 is the basic array of the antenna in embodiment 1,2. (a), (b), and (c) are the orthogonal dipole antenna in Embodiment 1, the 4×4 basic array radiation surface structure and the back structure in Embodiment 2, respectively. In the figure: 9, a dipole antenna simulating a vertical polarization, 10 , a dipole antenna simulating a horizontal polarization, 11 , a feeding port, 12 , a radiation unit.

Accompanying drawing 5 is the connection schematic diagram of several basic arrays in embodiment 2. In the figure: 13. The connection mode of connecting the radiating units by the equal-amplitude in-phase feed network, and 14. The connection mode of connecting the radiating units by the equal-amplitude anti-phase feed network. The left side of the figure is the connection mode of the antenna radiation surface feed network, and the right side is the connection mode of the antenna back feed network.

Figure 6 is two sets of 8×4 and 8×8 orthogonally polarized planar array antennas used in Embodiment 2.

Figure 6(a) is an array diagram of 8×4 microstrip in-phase arrangement, the upper part shows the structure of the radiation surface of the antenna, and the lower part shows the structure of the back side of the antenna.

Figure 6(b) is an array diagram of 8×4 microstrips arranged in π-phase, the upper part shows the structure of the radiation surface of the antenna, and the lower part shows the structure of the back side of the antenna.

Figure 6(c) is an array diagram of 8×8 microstrip in-phase arrangement, the upper part shows the structure of the radiation surface of the antenna, and the lower part shows the structure of the back side of the antenna.

Figure 6(d) is an array diagram of 8×8 microstrip π-phase arrangement, the upper part shows the structure of the radiation surface of the antenna, and the lower part shows the structure of the back side of the antenna.

Fig. 7 is a schematic diagram of comparison between the mirror-symmetrical cross-polarization suppression method of adjacent radiation units and the suppression method proposed in the present invention. In the figure: 15, a feed port of a planar array antenna with symmetrical adjacent radiation units, and 16, a feed port of a planar array antenna with a symmetrical basic array.

Figure 8 shows a specific application structure diagram of the cross-polarization suppression method in the present invention.

The sub-figure in the upper left corner of the figure represents a circularly polarized planar array antenna, the sub-figure in the upper right corner represents an orthogonally polarized planar array antenna with an irregular cross structure, and the sub-figure below represents the basic structure of an orthogonally polarized planar array antenna with an irregular cross structure array.

In the figure: 17, a circularly polarized planar array antenna, 18 represents a 0° feed port (for convenience of description), 19 represents a 180° feed port, 20 represents a 90° feed port, and 21 represents a 270° feed port, 22. An orthogonally polarized planar array antenna with an irregular cross structure. 23. A basic array of an orthogonally polarized planar array antenna with an irregular cross structure.

Figure 9 shows the relationship between the cross-polarization of the radiating element and the cross-polarization isolation of the orthogonally polarized planar array antenna calculated according to Embodiment 1 when θ=0°.

Accompanying drawing 10 is the effect diagram of improving the axial ratio of the 8×8 circularly polarized planar array antenna in FIG. 7 .

Accompanying drawing 11 is that in Fig. 7 the irregular cross structure orthogonally polarized planar array antenna is in Planar horizontal-polarization cross-polarization isolation graph.

Accompanying drawing 12 is the full-wave simulation result diagram of the antenna in embodiment 2.

Accompanying drawing 13 is the diagram of the dark room measurement result of the antenna in embodiment 2.

Accompanying drawing 14 is the error analysis diagram caused by the asymmetry of the antenna in embodiment 2.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

The concrete implementation of the present invention adopts three kinds of antennas, three sub-figures of (a), (b), (c) as shown in Figure 1, and the outer frame in each sub-figure is a basic array in the antenna.

The first type of antenna: it is mainly composed of basic arrays arranged and connected. Each basic array is shown in Figure 1(a). The basic array is composed of 16 radiating elements connected in the form of 4×4. The unit has two orthogonal feed ports, and each basic array and each radiating element in the basic array are connected through a feeding network, and the radiating elements and their orthogonal feeding ports in each basic array are arranged in the same phase , that is, the arrangement of the two orthogonal feed ports of the radiating elements in the basic array is the same as the arrangement of the radiating elements, and each radiating element is copied in translation to form an array arrangement.

The second type of antenna: it is mainly composed of basic arrays arranged and connected. Each basic array is shown in Figure 1(b). The basic array is composed of 16 radiation units connected in the form of 4×4. Each radiation The unit has two orthogonal feed ports, each basic array and each radiating element in the basic array are connected through a feed network, and each radiating element in each basic array and its orthogonal feeding port are connected by Arranged in a horizontal mirror-symmetrical manner, that is, the layout of all the orthogonal feed ports of the 16 radiating elements in the basic array is the same as that of the radiating elements, and they are all arranged in a horizontal mirror-symmetrical manner. The straight center line is used as the axis of symmetry to carry out horizontal mirror symmetry to form an array arrangement.

The third type of antenna: it is mainly composed of basic arrays arranged and connected. Each basic array is shown in Figure 1(c). The basic array is composed of 16 radiating elements connected in the form of 4×4. The unit has two orthogonal feed ports, each basic array and each radiating element in the basic array are connected through a feed network, and each radiating element in each basic array and its orthogonal feeding port are connected by Arranged horizontally and vertically in a mirror-symmetrical manner, that is, the layout of all the orthogonal feed ports of the 16 radiating elements in the basic array is the same as that of the radiating elements, and they are arranged in a horizontal and vertical mirror-symmetrical manner, basically Each radiating unit of the array performs horizontal mirror symmetry with the vertical center line as the axis of symmetry, and then performs vertical mirror symmetry with the horizontal center line as the axis of symmetry to form an array arrangement.

FIG. 3 enumerates in detail the possible arrangement of orthogonally polarized planar array antennas with various feed structures after adopting the cross-polarization suppression method proposed by the present invention. For example, for the sub-figure in the upper left corner of Figure 3, the antenna structure can suppress the cross-polarized field of the antenna by arranging the two basic arrays in the right half and the bottom half in a mirror-symmetrical manner, or by In the lower half, two sets of basic arrays are arranged mirror-symmetrically.

Embodiments of the present invention are as follows:

The working frequency of all the antennas mentioned in the embodiments of the present invention is 5.8 GHz.

In order to quantitatively illustrate the suppression of cross-polarization in the far-field range, Embodiment 1 uses the following three formulas to represent the cross-polarization isolation of the horizontal ports of the three antennas:

in, , , i, j represent the ordinal number of the antenna unit, i, j are positive integer sets from 1 to M and 1 to N, XPD ₁ , XPD ₂ and XPD ₃ respectively represent the cross-polarization isolation of the three antennas, and are the cross-polarization field and the main polarization field of the radiating element, M represents the number of antenna elements in the horizontal direction, N represents the number of antenna elements in the vertical direction, k is the wave vector, d is the distance between the radiating elements, and θ is the antenna center is the pitch angle at the origin, is the azimuth angle with the center of the antenna as the origin.

Example 1:

In this embodiment, as shown in Figure 4, the radiation unit is composed of a group of orthogonal dipole antennas, wherein one dipole antenna 10 simulates horizontal polarization, and the other dipole antenna 9 simulates vertical polarization, forming an orthogonal Dipole antenna radiation unit, as shown in Figure 4 (a).

Assuming vertical polarization produces a cross-polarized field in the horizontal direction than the horizontally polarized main polarization field Only 3dB lower, in which case XPD ₁ , XPD ₂ and XPD ₃ are calculated. It can be seen from the formula that in the ideal case of the second antenna, when θ=0°, the cross-polarization fields of the second and third antennas will cancel each other.

The second antenna obtained through the mirror image symmetry in the first step, The cross-polarization isolation of horizontal polarization will be greatly improved. The third antenna obtained through the mirror image symmetry in the second step, The cross-polarization isolation of horizontal polarization will be greatly improved at 90°. Similar results are obtained when calculating cross-polarization isolation for vertical polarization. and The planes are the E-plane and H-plane of the antenna.

When the second type of antenna is obtained by rearranging the basic array in the lower half of the first type of antenna in the vertical direction, The in-plane cross-polarization isolation of 0° will be greatly improved.

From the analysis of the principle, it can be concluded that the mirror symmetry of the basic array makes the cross-polarization index of the orthogonally polarized planar array antenna such as the communication-in-motion antenna greatly improved at the maximum radiation direction θ=0°.

Figure 1 shows the antennas arranged in three ways, Figure 1(a) shows the arrays arranged in the same phase, and Figure 1(b) and Figure 1(c) both show the arrays arranged in π phase. E _C and E _P denote the cross-polarization field and the main polarization field, respectively.

Figure 1(a) to Figure 1(b) are the first step. In the first step, the feeding ports of radiating units 1 and 2 are rearranged so that they are mirror-symmetrical with the feeding ports of radiating units 3 and 4, as shown in Fig. 1(b).

Figure 1(b) to Figure 1(c) are the first step, and the second step is to rearrange the feeding ports of the radiating units 6 and 8 so that they are mirror-symmetrical with the feeding ports of the radiating units 5 and 7, as shown in Fig. 1(c).

With mirror symmetry at each step, the cross-polarization is stepwise in multiple The plane is improved. Figure 2 clearly illustrates the change of the cross-polarization isolation of the array. The first step makes 270° planar isolation improvement (b), the second step makes The isolation is improved at 90°, 180°, and 270° (c).

Example 2:

Embodiment 2 uses two groups of 8×4 and 8×8 dual-linearly polarized microstrip array antennas to demonstrate the above method. Each group of antennas is composed of a microstrip in-phase arrangement array and a microstrip π-phase arrangement array.

As shown in Fig. 4, the structure of the radiating surface of the basic array is shown in Fig. 4(b). The radiating surface is connected by each radiating unit 12 through electrode laying arrangement, and connected to the output feeding port 11 of the basic array. The back structure is shown in Figure 4(c). The back is composed of multiple Wilkinson microstrip power dividers cascaded and connected to the radiation unit.

The feeding network is evenly distributed on the radiating surface and its back, as shown in Figure 5, taking the 8×4 microstrip orthogonally polarized planar array antenna as an example, Figure 5(a) and Figure 5(b) are equal-amplitude feed Network 13 and constant-amplitude anti-phase feed network 14. It can be seen that two coaxial lines are connected to the Wilkinson microstrip inverting power splitter in the equal-amplitude inverting-phase feed network 14 . The radiating unit and the feeding network are printed on a three-layer FR4 substrate (dielectric constant 4.3, tangent loss 0.025), the thickness of the top layer is 1.6mm, the thickness of the bottom layer is 0.5mm, the middle layer is the ground layer, and the thickness of each radiation patch The size is 11.4×11.6mm ² .

As shown in Figure 6, in order to form dual polarization, the feed network is laid on both sides of the orthogonally polarized planar array. The radiating surface feed excites the vertically polarized field on the antenna, and the rear feed excites the horizontally polarized field on the antenna. 8×4 microstrips are arranged in phase with the orthogonally polarized planar array antenna’s radiation surface and back structure as shown in Fig. The radiating surface and the back structure of the orthogonally polarized planar array antenna with π phase arrangement are shown in Figure 6(b). The 32 radiating units are connected to the power division network arrangement of the radiating surface. Since the basic array of the vertically polarized electric field is symmetrical in mirror image, Therefore, the two groups of power distribution networks on the back are respectively arranged and connected to the radiating units; the 8×8 microstrips are arranged in phase with the radiating surface of the orthogonally polarized planar array antenna and the structure of the back is shown in Figure 6(c). The 64 radiating units are respectively connected to the radiating surface and The two groups of power division networks on the back are arranged and connected; 8×8 microstrips are arranged in π phase and the radiation surface and the back structure of the orthogonally polarized planar array antenna are shown in Figure 6(d). The power division network layout of 64 radiation units and the radiation surface Connection, since the basic array of horizontally and vertically polarized electric field antennas is mirror-symmetrical, the four groups of power distribution networks on the radiating surface and the back need to be arranged and connected to the radiating units separately.

The difference between the 8×4 and 8×8 microstrip π-phase arrays is that the former contains two 4×4 basic arrays and are mirror-symmetrical in the horizontal direction, while the latter’s four 4×4 basic arrays are mirrored in both horizontal and vertical directions. symmetry.

The difference between the microstrip in-phase and π-phase arrangement arrays in this embodiment is that since the basic array needs to be fed inversion every mirror symmetry, the designed microstrip inverting power divider is to provide two mirror-symmetric ports of the antenna. Differential phases, so that the microstrip π-phase arrangement array requires more than two (not including two) feed ports to respectively feed the horizontal polarization and vertical polarization of the basic array that are mirror-symmetrical to each other.

Calculated by simulation and The cross-polarization isolation of the planar antenna array is measured and calculated in the microwave anechoic chamber with the help of a vector network analyzer to obtain the cross-polarization isolation of the real object.

The two microstrip π-phase arrays have achieved great improvement at the maximum radiation direction θ=0°, and the 8×8 array has obtained better cross-polarization in a larger radiation angle range. isolation.

Figure 12 and Figure 13 compare the simulated and measured cross-polarization isolation results of 8×4 and 8×8 microstrip in-phase and π-phase arrays, and Figure 12 shows that the two arrays are in The simulation results of the cross-polarization isolation of planar horizontal polarization and vertical polarization, Figure 13 shows that the two arrays are respectively in Cross-polarization isolation measurement results for planar horizontal and vertical polarizations. The microstrip π-phase arrangement array corresponds to the planar array antenna (b) and the planar array antenna (c) obtained by the planar array antenna (a) in Fig. The arrangement array is basically a symmetrical antenna in the horizontal direction. Ideally, the cross-polarization performance of the antenna far field will be greatly improved over a large angular range. It can be seen from the comparison of the microstrip in-phase and π-phase arrays that the cross-polarization isolation will be effectively improved, especially in the maximum radiation direction θ=0°. The improvement effect obtained by the simulation experiment is above 60dB, and the improvement effect obtained by the darkroom measurement is 10dB above.

The asymmetry of the basic array will affect the cross-polarization isolation of the orthogonally polarized planar array antenna to a certain extent. Figure 14 shows the relationship between the position error of the basic array and the cross-pole The relationship between polarization isolation, an orthogonally polarized planar array antenna designed by cross-polarization suppression method is highly sensitive to asymmetry.

Based on the formulas for calculating the cross-polarization isolation of the three antennas in Example 1, the curve results shown in Figure 9 can be calculated and obtained. The horizontal axis represents the cross-polarization isolation of the radiating element in horizontal polarization or vertical polarization, and the vertical axis represents the plane Array antenna cross-polarization isolation. Ideally, unit cross-polarization has no effect on the mirror-symmetrical planar array antenna, and the cross-polarization of the planar array antenna is completely suppressed at θ=0°. It can be seen that the present invention does not need to design a relatively complicated radiation unit structure to meet the cross-polarization index, and the cross-polarization tolerance of the unit is greatly improved.

Figure 7 shows a closely coupled planar array antenna with symmetrical adjacent radiating elements and a tightly coupled planar array antenna with basic symmetric arrays, and the distance between the radiating elements is one-third of the wavelength. In the method of symmetry of adjacent radiating elements, for antennas of the same size and shape, the energy coupling between the ports 15 of the two adjacent elements in the center is about -18.3dB. However, this suppression method has been verified by simulation. For a tightly coupled planar array antenna, the energy coupling at the ports 16 of the two adjacent central units is about -21.3 dB, and the near-field coupling is slightly smaller. It can be seen that, compared with the method in which adjacent radiating elements are symmetrical in the present invention, the influence of the near-field coupling effect in the tightly coupled array antenna is slightly smaller.

As shown in Figure 7, since the adjacent radiating elements are symmetrical, it is also necessary to ensure that the feeding phase is reversed. Therefore, in the case of using the feeding microstrip line for feeding, the symmetrical radiating element feeding microstrip line will change due to its electrical length requirements. , so its physical size needs to be redesigned. In this case, it is often necessary to extend the feeding microstrip line, and it is a difficult point to design the feeding network when the surface space of the antenna is limited. Assuming that the complexity of inverting once is 1, the method proposed by the present invention only needs to invert once for horizontal polarization or vertical polarization, and the complexity is 2. However, the complexity of the method in which adjacent radiating elements are symmetrical is n, where n is the total number of radiating elements. It can be seen that the adjustment of the basic array level of the present invention makes the feed network only need to consider the anti-phase structural design when the power is distributed for the first time. The complexity of the antenna array is greatly reduced under the premise of the index.

FIG. 8 shows the rear circularly polarized planar array antenna 17 and the orthogonally polarized planar array antenna 22 with an irregular cross structure. The 0° feed port 18 and the 90° feed port 20 of the circularly polarized planar array antenna are mirror-symmetrical, the 180° feed port 19, and the 270° feed port 21 are mirror-symmetrical and irregular cross-structure orthogonally polarized planar array antennas. A basic array 23 comprising three radiating elements is formed. It can be seen from FIG. 10 that the axial ratio (AR) of the circularly polarized planar array antenna in the maximum radiation direction can be improved by adopting the cross-polarization suppression method. However, FIG. 11 shows that the cross-polarization isolation of the orthogonally polarized planar array antenna with an irregular cross structure can be greatly improved by adopting the cross-polarization suppression method. It can be seen that the antenna polarization form applicable to the present invention is wider, and the shape of the basic array is not limited to square or rectangle.

It can be seen that the present invention adopts the method of arranging the basic arrays of the radiation aperture surface mirror symmetrically, regards the surface of the planar array antenna as consisting of even or odd basic arrays with the same number of radiating elements, and makes the adjacent basic arrays mirror symmetrical. A good cross-polarization suppression effect is obtained. For the basic arrays that are mirror symmetrical to each other, the equal-amplitude and anti-phase feeding method is adopted, and the symmetrical characteristics of the antenna are used to ensure that the cross-polarized field radiated by each basic array is in the far field under the condition that the main polarization field is basically unaffected. Within the beam range, especially in the normal radiation direction, mutual suppression.

Claims (9)

1. An orthogonally polarized planar array antenna that adopts cross-polarization suppression method design, is characterized in that: it is the antenna structure of horizontal or vertical direction mirror symmetry, or horizontal and vertical direction simultaneously mirror symmetry. 2. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 1, characterized in that: the antenna is mainly arranged and connected by a basic array, and the basic array is composed of The radiating units of two orthogonal feeding ports are connected, and the basic arrays and the radiating units in the basic array are connected through the feeding network. Each radiating unit in each basic array and its orthogonal feed The electrical ports are arranged in a horizontal or vertical mirror-symmetrical manner or in a simultaneous horizontal and vertical mirror-symmetrical manner. 3. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 1, characterized in that: said antenna is mainly composed of the top layer, the bottom layer and the stratum between the top layer and the bottom layer , the top surface is the radiation surface, the bottom surface is the back surface, and the radiation surface and the back surface are evenly distributed with feed networks. 4. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 3, characterized in that: when arranged in the horizontal mirror-symmetrical manner, the radiating surface adopts equal-amplitude and same-phase feed Electric network, the back adopts equal-amplitude anti-phase feed network; when arranged in the vertical mirror-symmetrical manner, the radiating surface adopts equal-amplitude anti-phase feed network, and the back adopts equal-amplitude in-phase feed network; When the mirrors are arranged horizontally and vertically at the same time, the radiating surface and the back are both equipped with equal-amplitude anti-phase feed networks. 5. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 4, characterized in that: the specific layout structure of the equal-amplitude and in-phase feed network is similar to that of Wilkinson work The multi-level microstrip power division network of the splitter, the number of stages of the power division network is half of the total number of antenna radiation units. 6. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 4, characterized in that: the specific layout structure of the equal-amplitude anti-phase feed network is the same as the equal-amplitude in-phase feed The network difference is that the difference in the length of the microstrip line at the two output ends of the first-stage power division is 180°. 7. A kind of orthogonally polarized planar array antenna designed by cross-polarization suppression method according to claim 3, characterized in that: the material of the formation is pure copper, and the top layer and the bottom layer are both substrates made of FR4 . 8. A cross-polarization suppression method for an orthogonally polarized planar array antenna, characterized in that: the basic array of antennas is subjected to mirror-symmetrical processing to form an antenna that is mirror-symmetrical in the horizontal or vertical direction, or simultaneously mirror-symmetrical in the horizontal and vertical directions The structure enables the antenna to work in the orthogonal polarization mode. 9. The cross-polarization suppressing method of a kind of orthogonally polarized planar array antenna according to claim 8, characterized in that: the basic array of antennas can be obtained by translational copying of the radiating elements, or the The arrangement method is used at the basic array level, and the basic array can also be further divided into multiple mirror-symmetrical small basic arrays.