WO2020151297A1

WO2020151297A1 - Microstrip radiation unit and array antenna

Info

Publication number: WO2020151297A1
Application number: PCT/CN2019/115523
Authority: WO
Inventors: 骆胜军; 潘波; 程季
Original assignee: 武汉虹信通信技术有限责任公司
Priority date: 2019-01-22
Filing date: 2019-11-05
Publication date: 2020-07-30
Also published as: EP3916906A1; EP3916906A4; CN109755721A; CN109755721B

Abstract

The embodiments of the present disclosure provide a microstrip radiation unit and an array antenna. The microstrip radiation unit comprises a dielectric base material, a radiation circuit and a feed circuit. The dielectric base material is integrally formed by injection molding, and the dielectric base material comprises a top portion, a support portion and a welding portion, the support portion being respectively connected to the top portion and the welding portion; and the radiation circuit is arranged on an upper surface of the top portion, and the feed circuit is arranged on a lower surface of the top portion and extends along the support portion to the welding portion. The microstrip radiation unit and the array antenna provided in the embodiments of the present disclosure realize the integration of the radiation unit, so that the radiation unit has a simple structure, and does not need to be assembled, improving the reliability and consistency of the radiation unit, and being suitable for large-scale manufacturing. In addition, the microstrip radiation unit has a good low-profile feature, effectively reducing the height of the radiation unit, further reducing the weight of the radiation unit, and achieving a lightweight radiation unit.

Description

Microstrip radiating element and array antenna

Cross references to related applications

This application claims the priority of the Chinese patent application filed on January 22, 2019 with the application number 2019100580175 and the invention title "Microstrip radiating element and array antenna", which is fully incorporated into this disclosure by reference.

Technical field

The embodiments of the present disclosure relate to the field of communication technologies, and in particular, to a microstrip radiating unit and an array antenna.

Background technique

With the rapid development of mobile communication technology, the 5th-Generation (5G) mobile communication technology (5th-Generation, 5G) applies large-scale antenna technology, deploying dozens or even hundreds of antenna-scale antenna arrays at the base station to increase network capacity. The large-scale antenna technology in the 5G era has turned the antenna into an integrated active antenna (Active Antenna Unit, AAU). AAU integrates the antenna and the radio remote unit (RRU), resulting in a straight line in the weight of the AAU. The rise brings great troubles to the load-bearing and construction of the tower, so the lightweight antenna has become the most intuitive problem that needs to be solved.

The existing radiation unit mainly includes the following three solutions. The first solution is to use an aluminum alloy integral die-casting structure. Due to the use of a high-density metal base material, the weight of the vibrator is heavier, which does not meet the demand for lightweight large-scale antennas. Moreover, the radiating part and the feeding part are separated, and the assembly is relatively complicated, which is not suitable for large-scale automated production. The second solution uses a PCB structure. The radiating part and the feeding part are etched on different flat substrate PCBs, and then the various components are welded together to produce electrical contact. Although this implementation method greatly reduces the weight of the radiating unit, Due to the large number of parts, complex assembly and low reliability, it is very unfavorable for large-scale automated production. The third scheme is improved on the basis of the first scheme. The radiator part is made of engineering plastic injection molding, and then the whole is electroplated. Although the weight of the radiating unit is reduced, the radiating part and the feeding part still belong to Separate structure, assembly is still complicated.

Therefore, it is still an urgent problem for those skilled in the art to meet the requirements of simplification of assembly while realizing the lightweight of the radiation unit to facilitate large-scale automated production.

Summary of the invention

The embodiments of the present disclosure provide a microstrip radiating unit and an array antenna to solve the problems of heavy weight and complicated assembly of the existing radiating unit.

In a first aspect, embodiments of the present disclosure provide a microstrip radiation unit, including a dielectric substrate, a radiation circuit, and a feed circuit;

Wherein, the media base material is integrally injection molded, and the media base material includes a top part, a support part and a welding part, and the support part is connected to the top part and the welding part respectively;

The radiation circuit is arranged on the upper surface of the top, and the feed circuit is arranged on the lower surface of the top and extends along the support part to the welding part.

In a second aspect, embodiments of the present disclosure provide an array antenna, including a plurality of microstrip radiating units as provided in the first aspect, and a feeding network for installing each of the microstrip radiating units.

The embodiment of the present disclosure provides a microstrip radiating unit and an array antenna. The weight of the radiating unit is reduced by an integrally injection-molded dielectric substrate, and the radiating circuit and the feeding circuit are both arranged on the dielectric substrate to realize the radiating unit The integration, simple structure, no assembly required, improved reliability and consistency of the radiation unit, and more suitable for large-scale manufacturing. In addition, the single-layer radiation circuit is used to realize the microstrip radiation unit, which has good low profile characteristics, effectively reduces the height of the radiation unit, further reduces the weight of the radiation unit, and realizes the lightweight of the radiation unit.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description These are some embodiments of the present disclosure. For those of ordinary skill in the art, the rest of the drawings can be obtained based on these drawings without creative work.

FIG. 1 is a schematic structural diagram of a microstrip radiation unit provided by an embodiment of the disclosure;

2 is a schematic structural diagram of a microstrip radiation unit provided by another embodiment of the disclosure;

FIG. 3 is a top view of a microstrip radiation unit provided by an embodiment of the disclosure;

4 is a top view of a microstrip radiation unit provided by another embodiment of the disclosure;

Figure 5 is a top view of a microstrip radiation unit provided by an embodiment of the disclosure;

FIG. 6 is a schematic structural diagram of an array antenna provided by an embodiment of the disclosure;

FIG. 7 is a schematic structural diagram of a feed network provided by an embodiment of the disclosure;

FIG. 8 is a schematic diagram of differential feeding of an integrated microstrip radiating unit provided by an embodiment of the disclosure.

Description of reference signs:

1-Microstrip radiation unit; 11-Media base material; 12-Radiation circuit;

13-Feeding circuit; 14-Non-conductive area; 15-Stiffener;

111-Top; 112-Support part; 113-Welding part;

114-Extended hole; 1131-plug pin; 1132-slotted;

121-Top radiation circuit; 122-Extension radiation circuit; 131-Top feeder circuit;

132-Intermediate connection part; 133-Bottom welding part; 2-Feeding network;

21- Feeding port.

detailed description

In order to make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments It is a part of the embodiments of the present disclosure, but not all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure.

In order to solve the problem that the existing radiation unit is generally heavy, does not meet the requirements of large-scale antenna lightweight, and the assembly is relatively complicated, and is not suitable for large-scale automated production, embodiments of the present disclosure provide a microstrip radiation unit ，While realizing the light weight of the radiation unit, it also meets the requirements of simplification of assembly. Figure 1 is a schematic structural diagram of a microstrip radiation unit provided by an embodiment of the disclosure. As shown in Figure 1, the microstrip radiation unit includes a dielectric substrate 11, a radiation circuit 12, and a feed circuit 13; wherein the dielectric substrate 11 is integrated In injection molding, the dielectric substrate 11 includes a top portion 111, a support portion 112, and a welding portion 113. The support portion 112 is connected to the top portion 111 and the welding portion 113, respectively; the radiation circuit 12 is arranged on the upper surface of the roof 111, and the feed circuit 13 is arranged on the top 111 The lower surface extends along the supporting portion 112 to the welding portion 113.

Specifically, the dielectric substrate 11 is a single part that includes a top part 111, a support part 112 and a welding part 113 from top to bottom. The support part 112 is a connecting part between the top part 111 and the welding part 113. The support part 112 may be a single columnar structure shown in FIG. 1, or may be composed of a plurality of supporting components. Here, the side of the top 111 in contact with the supporting portion 112 is confirmed as the lower surface of the top 111, and accordingly the side of the top 111 not in contact with the supporting portion 112 is confirmed as the upper surface of the top 111. The radiating circuit 12 is arranged on the upper surface of the top 111. The radiating circuit 12 can completely cover the upper surface of the top 111, or it can be arranged on the upper surface of the top 111 in a shape consistent with the upper surface of the top 111, or it can be arranged on the top 111 based on a preset shape. The preset position of the upper surface is not limited in the embodiment of the present disclosure. Correspondingly, the feeder circuit 13 is arranged on the back of the arrangement surface of the radiation circuit 12, that is, the lower surface of the top 111, and the supporting portion 112 contacting the lower surface of the top 111, and finally extends to the soldering portion 113 to facilitate the operation in the microstrip radiation unit During installation, when the welding part 113 is connected to the feeding network, the electric connection between the feeding circuit 13 and the feeding network is realized through the welding part 113. It should be noted that the radiating circuit 12 is arranged on the upper surface of the top 111, the feeding circuit 13 is arranged on the lower surface of the top 111, and the specific arrangement position of the radiating circuit 12 on the upper surface of the top 111 and the specific arrangement of the feeding circuit 13 on the lower surface of the top 111 The arrangement positions are corresponding, so that the radiation circuit 12 arranged on the upper surface of the top 111 and the feed circuit 13 arranged on the lower surface of the top 111 form a radiating unit for coupling and feeding.

In addition, the arrangement of the radiating circuit 12 and the feeding circuit 13 on the dielectric substrate 11 can be implemented by 3D-MID (3D Molded Interconnect Device) technology.

The microstrip radiation unit provided by the embodiment of the present disclosure reduces the weight of the radiation unit through the integrated injection-molded dielectric substrate 11, and both the radiation circuit 12 and the feed circuit 13 are arranged on the dielectric substrate 11 to realize the Integration, simple structure, no assembly required, improved reliability and consistency of the radiation unit, and more suitable for large-scale manufacturing. In addition, the single-layer radiation circuit is used to realize the microstrip radiation unit, which has good low profile characteristics, effectively reduces the height of the radiation unit, further reduces the weight of the radiation unit, and realizes the lightweight of the radiation unit.

Based on the above embodiment, FIG. 2 is a schematic structural diagram of a microstrip radiation unit provided by another embodiment of the present disclosure. As shown in FIG. 2, in the microstrip radiation unit, an extension hole 114 is opened in the center of the top 111, and the extension hole 114 is The support part extends in the direction of the welding part; the radiation circuit is extended to the wall of the extension hole 114.

Specifically, an extension hole 114 is opened in the center of the top 111, and the extension hole 114 extends in the direction of the welding part. Here, the extension hole 114 may be a through hole, that is, the support part and the welding part of the dielectric substrate are of hollow design, and the extension hole 114 It may also be a blind hole, that is, the extension hole 114 extends in the support portion but is not opened, which is not specifically limited in the embodiment of the present disclosure. By opening the extended holes 114 in the dielectric substrate, the materials used can be further reduced, and the weight of the microstrip radiation unit can be reduced.

On this basis, the radiation circuit arranged on the upper surface of the top 111 is extended to the wall of the extension hole 114. In FIG. 2, the radiation circuit is divided into two parts, one part is the radiation circuit arranged on the upper surface of the top 111. The other part of the top radiation circuit 121 is the radiation circuit extending to the wall of the extension hole 114, that is, the extension radiation circuit 122. Since the extension hole 114 is a hole opened in the center of the support part, the support part can be regarded as a hollow design, the hole wall of the extension hole 114 is regarded as the inner wall of the support part, and the surface of the support part on which the feed circuit is arranged is regarded as the support part By extending the radiation circuit on the inner wall of the supporting part, the cross-polarization index of the microstrip radiation unit can be greatly improved.

Based on any of the foregoing embodiments, in the microstrip radiation unit, a non-conductive area is also arranged on the radiation circuit.

Specifically, in order to improve the polarization isolation, a non-conductive area is also provided on the upper surface of the top. The embodiment of the present disclosure does not limit the shape, number, and specific location of the non-conductive area. FIG. 3 is a top view of the microstrip radiation unit provided by an embodiment of the disclosure. As shown in FIG. 3, the top 111 of the dielectric substrate is circular, the top 111 is provided with a radiation circuit 12, and the center of the top 111 is provided with an extension hole 114, The center of 111 is the center, and four groups of non-conductive areas 14 are evenly distributed on the upper surface, and each non-conductive area 14 is in a line shape. 4 is a top view of a microstrip radiation unit provided by another embodiment of the present disclosure. As shown in FIG. 4, the top 111 of the dielectric substrate is octagonal, the top 111 is provided with a radiation circuit 12, and the center of the top 111 is provided with an extension hole 114 , With the center of the top 111 as the center, four groups of demetallized non-conductive regions 14 are evenly distributed on the upper surface, and each non-conductive region 14 is a figure eight.

Based on any of the above embodiments, in the microstrip radiation unit, a reinforcing rib is also arranged on the top.

Specifically, by adding stiffeners on the top of the media base material, the structural strength of the integrated media base material and the flatness of the top planar structure can be improved, and the “mouth”-shaped skirt ribs can be provided at the periphery of the top. A cross-shaped stiffener may be provided on the top surface based on the top center, which is not specifically limited in the embodiment of the present disclosure.

Based on any of the above embodiments, in the microstrip radiation unit, the radiation circuit and the feed circuit are arranged symmetrically based on the central axis of the dielectric substrate. Therefore, when the microstrip radiation unit is used as a single component for the whole machine assembly, the radiation unit and the feed circuit The electrical connection assembly of the network does not require additional identification, which is very suitable for automated production in large-scale array antenna applications.

Based on any of the above embodiments, FIG. 5 is a top view of the microstrip radiating unit provided by the embodiment of the disclosure. As shown in FIG. 5, the microstrip radiating unit includes four groups of feeder circuits 13, and the four groups of feeder circuits 13 are dielectric The center axis of the substrate 11 is uniformly distributed on the axis.

Specifically, each group of feeder circuits 13 has the same structure, and is distributed in 90° rotation along the central axis in sequence. Here, the microstrip radiation unit including four groups of feeder circuits 13 is a dual-polarized radiation unit. Each polarization of the dual-polarized radiation unit is differentiated by two groups of feeder circuits 13 arranged oppositely and symmetrically (with a 180° phase difference). ) Feeding to suppress high-order modes, further reduce the coupling between the two ports, and improve the pattern consistency and isolation of the dual-polarized oscillator +45° polarization and -45° polarization.

Based on any of the foregoing embodiments, in the microstrip radiation unit, the welding portion 113 includes four pins 1131 evenly distributed around the center axis of the dielectric substrate 11, and each feed circuit 13 wraps a pin 1131 .

Specifically, referring to FIG. 5, each feeder circuit 13 includes a top feeder circuit 131, an intermediate connection portion 132, and a bottom soldering portion 133. The top feeder circuit 131 is the set of feeder circuits 13 arranged on the top 111 of the dielectric substrate. The middle connecting portion 132 is the part of the group of feeding circuits 13 that is laid on the dielectric substrate support 112 to connect the top feeding circuit 131 and the bottom welding portion 133, and the bottom welding portion 133 is the group of feeding circuits 13 It is arranged on the welding part 113 of the dielectric base material 11 and is wrapped around a part of a pin 1131 corresponding to the welding part 113. Here, the bottom welding part 133 of the wrapping pin 1131 is used to electrically connect with the feed network port to realize signal excitation.

Based on any of the foregoing embodiments, referring to FIG. 5, in the microstrip radiation unit, a slot 1132 is provided between any two adjacent pins 1131 of the welding portion 113. Through the arrangement of the slot 1132, the weight of the integrated media substrate 11 is further reduced. Here, the slot 1132 may be a slot of various shapes such as a U-shaped groove and a V-shaped groove.

Based on any of the above embodiments, the microstrip radiation unit is a three-dimensional molded interconnection device, and the entire microstrip radiation unit is a single component, which simplifies the supply chain, has a simple structure, improves the reliability and consistency of the radiation unit, and is suitable for large-scale manufacture.

Based on any of the foregoing embodiments, FIG. 6 is a schematic structural diagram of an array antenna provided by an embodiment of the present disclosure. As shown in FIG. 6, the array antenna includes a plurality of microstrip radiating units 1, and is used to install each microstrip radiating unit 1. The feeder network 2.

Specifically, each microstrip radiating unit 1 is welded to the feeder network 2 through the welding part of the dielectric substrate to realize the electrical connection between the feeder circuit and the feeder network 2. The welding part can be a pin type welding structure, or It may be a soldering type welding structure, and the embodiment of the present disclosure does not specifically limit the installation method between the microstrip radiation unit 1 and the feed network 2.

FIG. 7 is a schematic structural diagram of a feed network provided by an embodiment of the disclosure. Referring to FIG. 7, a number of feed ports 21 are provided on the feed network 2 for electrical connection with the welding part of the microstrip radiation unit. In Fig. 7, four feed ports 21 are provided for the microstrip radiation unit with four pins in the welding part, and each pin corresponds to a feed port 21. The four pins have rotational center symmetry. In this case, during assembly, only the four pins need to be directly connected to the four feed ports 21, without additional identification, blind mating assembly can be realized, which can significantly shorten the assembly time in antenna production and improve assembly efficiency , Very suitable for realizing automated production in large-scale array antenna applications.

FIG. 8 is a schematic diagram of differential feeding of an integrated microstrip radiating unit provided by an embodiment of the disclosure, including an integrated microstrip radiating unit 1 and a differential feeding network 2 thereof. With reference to Figures 7 and 8, the four solder pins of the integrated radiating unit are blindly inserted into the four feed ports of the differential feed network 2 without additional identification. In the differential feed network 2, the two feed ports 21a and 21b (or 22a and 22b) of the same set of polarizations are arranged oppositely and have a phase difference of 180°.

Referring to FIG. 5, the microstrip radiation unit 1 includes a dielectric substrate 11, a radiation circuit 12 and a feeding circuit 13. The dielectric substrate 11 is an integrated structure and is integrally injection molded from high temperature resistant engineering plastics. The dielectric substrate 11 includes a top 111, a supporting portion 112, a welding portion 113 and a reinforcing rib 15. An extension hole 114 is provided at the center of the top 111, and The supporting portion 112 forms a smooth transition structure, which is unobstructed from the top view. The radiation circuit 12 includes a top radiation circuit 121 provided on the upper surface of the top 111 of the dielectric substrate and an extension radiation circuit 122 provided on the surface of the extension hole 114. In addition, the top radiation circuit 121 is provided with a demetallization gap, that is, non-conductive. Area 14. The feeding circuit 13 includes a top feeding circuit 131 arranged on the lower surface of the top 111 of the dielectric substrate, an intermediate connecting portion 132 arranged on the outer wall surface of the dielectric substrate supporting portion 112, and a welding portion 113 arranged on the dielectric substrate and covering the entire dielectric substrate. The bottom welding portion 133 of the four welding legs of the material welding portion 113.

Here, the planar structure of the top 111 of the dielectric substrate is a square, and can also be a round or other polygonal structure. The extended hole 114 provided in the center of the top 111 can reduce materials and reduce the weight of the integrated dielectric substrate 11. The top radiation circuit 121 provided on the top 111 of the dielectric substrate has a circuit shape consistent with the planar shape of the top 111 of the dielectric substrate 11. On the top radiating circuit 121, with the central axis of the dielectric substrate 11 as the axis, four groups of non-conductive regions 14 with the same structure are arranged, and the shape is "one" or "Λ" or other deformed shapes to improve the pole化 Isolation. The extension radiating circuit 122 extending downwardly from the extension hole 114 of the top portion 111 of the dielectric substrate and the connecting portion of the dielectric substrate support portion 112 toward the inner surface of the dielectric substrate support portion 112, that is, the wall of the extension hole 114, can greatly Improve the cross-polarization ratio index of the microstrip radiation unit 1.

Reinforcing ribs 15 are respectively arranged on the peripheral edges of the top 111 of the media substrate, forming a “mouth” skirt, and the center of the bottom surface of the top 111 is a “cross” to improve the structural strength of the integrated media substrate 11 and the plane of the top 111 The flatness of the structure. In addition, the supporting portion 112 forms a hollow closed structure to enhance the structural strength of the integrated media substrate 11. The supporting portion 112 may be a barrel shape or other closed shapes. The welding part 113 includes four socket pins 1131 that rotate around 90°, and the socket pins 1131 are provided with “U”-shaped slots 1132 in two adjacent areas to further reduce the weight of the integrated dielectric substrate 11.

The microstrip radiating unit 1 includes a total of four groups of feeding circuits 13, each of which has the same structure and is distributed along the central axis 90° in turn. For a single feeder circuit 13, the top feeder circuit 131 arranged on the bottom surface of the top 111 of the feeder circuit 13 and the radiation circuit 12 form a radiating unit coupling feed, and the middle connecting portion 132 connects the top feeder circuit 131 and the bottom welding portion 133 , In order to realize the continuous electrical connection of the entire feeder circuit 13. The bottom welding part 133 of the wrapping pin 1131 is used for electrical connection with the feeding port of the feeding network 2 to realize signal excitation. Here, the bottom welding portion 133 may be configured as a pin-type plug-welding type structure, or may be configured as a disc-shaped soldering type structure, which is not specifically limited in the embodiment of the present disclosure. The four groups of feed circuits 13 based on the above structure jointly realize the feed excitation of the dual-polarized microstrip radiation unit 1 to suppress high-order modes, further reduce the coupling between the two ports, and increase the dual-polarized oscillator +45° Polarization and -45° polarization pattern consistency and isolation. It should be noted that in the embodiments of the present disclosure, the coupling feed mode can effectively increase the matching bandwidth of the oscillator.

The microstrip radiation unit 1 provided by the embodiment of the present disclosure adopts a single-layer radiation circuit 12 structure. The overall height of the microstrip radiation unit 1 is less than 0.15λ (where λ represents the wavelength), and has good low profile characteristics; secondly, the microstrip The radiation unit 1 is specially equipped with an extended radiation circuit 122, which greatly improves the cross-polarization index of the microstrip radiation unit 1. Moreover, the microstrip radiation unit 1 is a 3D-MID molded interconnection device with very light weight and is suitable for Large-scale array antenna application, and the entire microstrip radiating unit 1 is a single component, which simplifies the supply chain, has a simple structure, improves the reliability and consistency of the radiating unit, and is suitable for large-scale manufacturing; in addition, the radiation of the microstrip radiating unit 1 The part and the feed part are all based on the center symmetry of the single component of the radiating unit. The four solder pins can be blindly inserted into the four feed ports of the feed network 2 without additional identification, which significantly shortens the assembly time in antenna production and improves assembly efficiency , Very suitable for realizing automated production in large-scale array antenna applications.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, not to limit it; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

A microstrip radiation unit, characterized in that it comprises a dielectric substrate, a radiation circuit and a feed circuit;

Wherein, the media base material is integrally injection molded, and the media base material includes a top part, a support part and a welding part, and the support part is connected to the top part and the welding part respectively;

The radiation circuit is arranged on the upper surface of the top, and the feed circuit is arranged on the lower surface of the top and extends along the support part to the welding part.
The microstrip radiation unit according to claim 1, wherein an extension hole is opened in the center of the top, and the extension hole extends in the direction of the welding part in the support part;

The radiation circuit is extended to the wall of the extension hole.
The microstrip radiation unit according to claim 1, wherein a non-conductive area is also arranged on the radiation circuit.
The microstrip radiation unit according to claim 1, wherein the top part is further provided with reinforcing ribs.
The microstrip radiation unit according to claim 1, wherein the radiation circuit and the feed circuit are both symmetrically arranged based on the central axis of the dielectric substrate.
The microstrip radiation unit according to claim 1, wherein the microstrip radiation unit comprises four groups of the feeder circuits, and the four groups of feeder circuits are centered on the central axis of the dielectric substrate. Evenly distributed.
The microstrip radiation unit according to claim 6, wherein the welding part includes four pins uniformly distributed around the central axis of the dielectric substrate, and each of the feed circuits is wrapped One of the pins.
8. The microstrip radiation unit according to claim 7, wherein a slot is provided between any two adjacent pins of the welding part.
8. The microstrip radiation unit according to any one of claims 1 to 8, wherein the microstrip radiation unit is a three-dimensional molded interconnection device.
An array antenna, characterized in that it comprises a plurality of microstrip radiating units according to any one of claims 1 to 9, and a feed network for installing each of the microstrip radiating units.