CN117134106A

CN117134106A - Printed antenna and communication device

Info

Publication number: CN117134106A
Application number: CN202210547280.2A
Authority: CN
Inventors: 武东伟; 邵金进; 石操
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-05-19
Filing date: 2022-05-19
Publication date: 2023-11-28
Also published as: WO2023221681A1

Abstract

A printed antenna and a communication device are disclosed to improve the horizontal plane gain and beam width of the printed antenna. The printed antenna is printed on a dielectric plate, and a radio frequency circuit board is further arranged on the dielectric plate and used for providing feed signals for the printed antenna, and the printed antenna comprises a printed array antenna and a printed feed network. The printed array antenna comprises N unit antennas, each unit antenna comprises a feed input end and a grounding end, the grounding ends are connected with the grounding point of the radio frequency circuit board, and N is an integer greater than or equal to 2. The printed feed network comprises a feed input port and N feed output ports, wherein the feed input port is connected with a feed point of the radio frequency circuit board, and the N feed output ports are connected with feed input ends of the N unit antennas one by one.

Description

Printed antenna and communication device

Technical Field

The present application relates to the field of wireless communications technologies, and in particular, to a printed antenna and a communication device.

Background

Printed circuit board (printed circuit board, PCB) printed antennas have the advantages of low cost, low manufacturing complexity, short feed lines and high efficiency, and are used in wireless products such as mobile terminals, routers and Access Points (APs).

PCB printed antennas can be classified into internal antennas and external antennas according to the deployment location in the product. The external antenna has better out-of-roundness of the radiation pattern and high average gain of the horizontal plane because the radiation surface is not shielded or reflected. However, the external antenna is far away from the single board, so that the printed microstrip line feed cannot be adopted, and the coaxial cable needs to be contacted from the circuit board to the antenna end feed. When the number of antenna channels is large, the wiring and wire arrangement costs of the coaxial cable become high, and manufacturability becomes poor.

Compared with an external antenna, the internal antenna can print microstrip line feed on a PCB, so that an additional coaxial cable is not needed, and the manufacturing and the assembly are simple. However, due to the reflection effect of the PCB, the problems of low horizontal plane gain, small effective coverage angle with high directivity, poor out-of-roundness and the like exist. How to improve the horizontal gain, beam width and reduce the out-of-roundness of the beam of a printed antenna of a PCB is a problem to be solved.

Disclosure of Invention

The application provides a printed antenna and communication equipment, which are used for improving the horizontal plane gain and beam width of the PCB printed antenna and reducing out-of-roundness.

A first aspect provides a printed antenna. The printed antenna is printed on a dielectric plate, a radio frequency circuit board is further arranged on the dielectric plate, the radio frequency circuit board and the printed antenna are formed integrally in a coplanar mode, and the radio frequency circuit board is used for providing feed signals for the printed antenna. The printed antenna comprises a printed array antenna 11 and a printed feed network. The printed array antenna is used for providing horizontal omnidirectional radiation and comprises N unit antennas, each unit antenna comprises a feed input end and a grounding end, the grounding end is connected with a grounding point of the radio frequency circuit board, and N is an integer greater than or equal to 2. The printed feed network comprises a feed input port and N feed output ports, wherein the feed input port is connected with a feed point of the radio frequency circuit board, and the N feed output ports are connected with feed input ends of the N unit antennas one by one. The printed array antenna is formed by a plurality of unit antennas through the printed feed network, so that the beam width and the horizontal plane gain are improved, the out-of-roundness of the horizontal beam of the printed antenna is reduced, and the printed feed network is free from cable integration, and has simple assembly and low cost.

In one possible implementation, the printed feed network is used to feed N unit antennas in parallel or in a series-parallel hybrid.

In one possible implementation, each unit antenna is a loop antenna. The loop antenna is small in size and high in reliability, so that miniaturization and high reliability of the printed antenna can be realized.

In one possible implementation, the printed array antenna includes a first unit antenna and a second unit antenna, and the printed feed network is used to feed the first unit antenna and the second unit antenna in parallel. Thus, the current distribution of each unit antenna can be well controlled to be uniform and the phase is consistent.

In one possible implementation manner, the printed array antenna is disposed on a first surface of the dielectric plate, the printed feed network includes a first feed output port and a second feed output port, the feed input port of the printed feed network and the first feed output port are disposed on the first surface of the dielectric plate, the first feed output port is connected with the feed input end of the first unit antenna, the second feed output port is disposed on a second surface of the dielectric plate through a first metallized via hole, and the second feed output port is connected with the feed input end of the second unit antenna through a second metallized via hole so as to avoid a grounding end of the second unit antenna, and the first surface and the second surface of the dielectric plate are opposite.

In one possible implementation, each unit antenna is a printed dipole antenna. The printed dipole is light in weight, so that miniaturization of the printed antenna and reduction of manufacturing cost can be realized.

In one possible implementation, each unit antenna includes a first dipole radiating arm, a second dipole radiating arm, and an L-shaped coupling feed line for balanced feeding of the first dipole radiating arm and the second dipole radiating arm, the first dipole radiating arm including a first ground terminal, the second dipole radiating arm including a second ground terminal, the first ground terminal and the second ground terminal being connected to a radio frequency circuit board, the L-shaped coupling feed line including a feed input terminal.

In one possible implementation, the L-shaped coupling feed line and the printed feed network are disposed on a first surface of the dielectric plate, and the first dipole radiating arm and the second dipole radiating arm are disposed on a second surface of the dielectric plate, the first surface and the second surface of the dielectric plate being opposite.

In one possible implementation manner, the N unit antennas are arranged in a linear shape, and a space between any two adjacent unit antennas in the N unit antennas meets an in-phase requirement. The N unit antennas maintain the same radiation phase, and can improve radiation gain.

A second aspect provides a communication device comprising a housing, a radio frequency circuit board and a printed antenna as claimed in any one of claims 1 to 9, the printed antenna and the radio frequency circuit board being disposed within the housing, the printed antenna being connected to the radio frequency circuit board, the radio frequency circuit board being arranged to provide a feed signal to the printed antenna.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of a PCB printed antenna according to the present application;

fig. 2 is a schematic structural diagram of an embodiment of a printed antenna according to the present application;

fig. 3 is an enlarged schematic view of a printed antenna according to the present application;

fig. 4 is a schematic structural diagram of another embodiment of a printed antenna according to the present application;

FIG. 5 is a schematic diagram of an embodiment of the printed antenna of FIG. 4 from a second surface perspective of the dielectric plate;

FIG. 6 is a schematic structural view of another embodiment of the printed antenna of FIG. 4 from a second surface perspective of the dielectric sheet;

FIG. 7 is a simulation of the surface current distribution of the printed antenna of FIG. 4;

FIG. 8 is a comparison of different printed antenna horizontal patterns;

FIG. 9 is a diagram comparing the simulation of the printed antenna of FIG. 2 with a horizontal pattern of a physical object;

fig. 10 is a schematic structural diagram of a printed antenna according to another embodiment of the present application;

FIG. 11 is a schematic view of the printed antenna of FIG. 10 from a second surface of the dielectric sheet;

fig. 12 is a schematic structural diagram of a printed antenna according to another embodiment of the present application;

FIG. 13a is a three-dimensional pattern of a conventional dipole printed antenna;

FIG. 13b is a three-dimensional pattern of the printed antenna of FIG. 9;

FIG. 13c is a three-dimensional pattern of the printed antenna of FIG. 10;

FIG. 14 is a comparison of different printed antenna horizontal patterns;

fig. 15 is a schematic structural diagram of an embodiment of a communication device according to the present application.

Detailed Description

The terms "first," "second," "third," "fourth" and the like in the description and in the claims and in the above drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments described herein may be implemented in other sequences than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The printed antenna is a printed antenna, and in order to reduce the volume of the antenna and reduce the power consumption under the condition of ensuring the transmission efficiency, the printed antenna can be designed on a dielectric plate so as to be suitable for the requirements of low-power-consumption and portable wireless communication products.

Fig. 1 is a schematic structural diagram of an embodiment of a PCB printed antenna according to the present application. In this embodiment, the printed antenna 10 is disposed on the dielectric plate 20. The dielectric plate 20 is also provided with a radio frequency circuit board 30. The dielectric plate 20 includes an antenna clearance area 21 and a copper-clad area 22, the printed antenna 10 is disposed in the antenna clearance area 21, and the radio frequency circuit board 30 is disposed in the copper-clad area 22. The radio frequency circuit board 30 is integrally formed with the printed antenna 10 in a coplanar manner. The printed antenna 10 is disposed on one side of the radio frequency circuit board 30. The radio frequency circuit board 30 is connected to the printed antenna 10 for feeding the printed antenna 10. The printed antenna 10 of the application is integrated with the radio frequency circuit board 30 in a coplanar manner without the need of profile height, can be formed by one-step processing, and has the advantages of no cable integration, simple assembly and low cost.

The material of the dielectric plate 20 is, for example, glass fiber epoxy (FR 4). Of course, the dielectric plate 20 may be a dielectric substrate made of other materials with high dielectric constant, which is not limited by the present application.

The radio frequency circuit board 30 may include a feed point 31 and a ground point (GND) 32. One end of the printed antenna 10 is connected to a feeding point 31 of the radio frequency circuit board 30 so that the radio frequency circuit board 30 can feed in a signal exciting the printed antenna 10. At least two other ends of the printed antenna 10 are connected to the ground point 32 of the radio frequency circuit board 30.

Specifically, the printed antenna 10 of the present application includes a printed array antenna 11 and a printed feed network 12. The printed feed network 12 is used to provide the required amplitude and phase for the printed array antenna 11, meeting the performance requirements of the printed array antenna 11.

The printed array antenna 11 includes N unit antennas 110, N being an integer greater than or equal to 2. Each unit antenna 110 includes a feed input 1101 and a ground 1102. The printed feed network 12 includes a feed input port 121 and N feed output ports 122. The ground 1102 of each unit antenna 110 is connected to the ground 32 of the radio frequency circuit board 30. The N feed output ports 122 of the printed feed network 12 are respectively connected with the feed input ends 1101 of the N unit antennas 110 one by one, that is, each feed output port 122 of the printed feed network 12 is respectively connected with the feed input end 1101 of one unit antenna 110, and the feed output ports 122 are in one-to-one correspondence with the feed input ends 1101. The feed input port 121 of the printed feed network 12 is connected to the feed point 31 of the radio frequency circuit board 30. Thus, the printed feed network 12 receives the feed signal transmitted from the radio frequency circuit board 30 through the feed point 31 and delivers the feed signal to the N unit antennas 110 to excite the N unit antennas 110.

In the present application, a printed array antenna 11 is used to provide horizontal omnidirectional radiation. The printed array antenna 11 is an ultra-wide beam antenna, i.e. the half-power beamwidth of the printed array antenna 11 is greater than 180 °, approaching a horizontal omni-directional antenna.

The N unit antennas 110 may be arranged in a straight line, so that the area occupied by the printed antenna 10 can be saved. Of course, when the number of the unit antennas 110 is large, the N unit antennas 110 may be arranged in a matrix or tree form, which is not limited in the present application.

The printed feed network 12 may feed N unit antennas 110 in parallel, or may feed N unit antennas 110 in series-parallel.

The spacing between any two adjacent unit antennas 110 of the N unit antennas 110 satisfies the in-phase requirement. Specifically, the interval between any two adjacent unit antennas 110 is 0.5 to 0.8 wavelength, thereby realizing in-phase radiation between the unit antennas 110.

In the present application, the sizes of the N unit antennas 110 may be uniform or non-uniform, and may be specifically determined according to the feeding method adopted in practical application, the center frequency of the printed antenna 10, and other factors, which are not limited herein.

The unit antenna 110 may be in the form of a loop antenna or a printed dipole antenna. The number of unit antennas 110 in the printed array antenna 11 is greater than or equal to 2. The number of unit antennas 110 may be specifically determined according to the gain expected to be obtained and the overall size of the printed array antenna 11, for example, the larger the gain expected to be obtained, the larger the number of unit antennas 110 may be, or the larger the overall size of the printed array antenna 11 can be designed, the larger the number of unit antennas 110 may be, which is not limited in the present application.

Fig. 2 is a schematic structural diagram of an embodiment of a printed antenna according to the present application, as shown in fig. 2 and 3; fig. 3 is an enlarged schematic view of a printed antenna according to the present application. In fig. 2, the unit antenna 110 is a loop antenna, and includes a first loop antenna 111 and a second loop antenna 112. The loop antenna has the advantages of small volume, high reliability and low cost, and becomes an ideal antenna of a microminiature communication product.

As shown in fig. 3, the first loop antenna 111 includes a first feed input 1111 and a first ground 1112. The first feed input 1111 and the first ground 1112 have a spacing therebetween, that is, the first feed input 1111 and the first ground 1112 are electrically disconnected. The first loop antenna 111 further includes, for example, a first loop antenna body 1113. The connection between the first feed input 1111 and the first ground 1112 and the first loop antenna body 1113 may form a closed loop. The feeding signal is input from the first feeding input 1111, flows through the first loop antenna body 1113, and is output from the first ground 1112, so that the first loop antenna body 1113 can be excited to emit a radiation signal.

The first loop antenna body 1113 may be formed by winding the first feeding input 1111 to the first ground 1112, or may be formed by winding the first ground 1112 to the first feeding input 1111. The loop antenna may be square as shown in fig. 1, but may be any other loop shape, such as a circular loop, a triangular loop, a diamond loop, etc., which is not limited herein.

The second loop antenna 112 includes a second feed input 1121, a second ground 1122, and a second loop antenna body 1123. The structure of the second loop antenna 112 is the same as that of the first loop antenna 111, and thus will not be described again.

The printed feed network 12 is illustrated as a parallel feed of the first loop antenna 111 and the second loop antenna 112. The printed feed network 12 includes a feed input port 121, a first feed output port 1221, and a second feed output port 1222. The radio frequency circuit board 30 includes a first ground point 321 and a second ground point 322. The feed input port 121 of the printed feed network 12 is connected to the feed point 31 of the radio frequency circuit board 30, the first feed output port 1221 is connected to the first feed input 1111 of the first loop antenna 111, and the second feed output port 1222 is connected to the second feed input 1121 of the second loop antenna 112. The first ground 1112 of the first loop antenna 111 is connected to the first ground 321, and the second ground 1122 of the second loop antenna 112 is connected to the second ground 322.

The feeding point 31 of the radio frequency circuit board 30 is located, for example, between the first ground point 321 and the second ground point 322, and the printed feeding network 12 is disposed between the two unit antennas 110. The printed feed network 12 further comprises, for example, a power divider 123, the power divider 123 being configured to divide the feed signal equally, so as to achieve a constant amplitude in-phase feed of the first loop antenna 111 and the second loop antenna 112. In fig. 3, the power divider 123 is exemplified as a T-type halving power divider, and the power divider 123 may be in other forms, which is not limited herein. The input of the power divider 123 communicates with the feed input port 121, the first output of the power divider 123 communicates with the first feed output port 1221, and the second output of the power divider 123 communicates with the second feed output port 1222, so that the overall structure of the printed feed network 12 also exhibits a T-shape. The feeding signal inputted through the feeding input port 121 is divided into two by the power divider 123, and is fed to the first loop antenna 111 and the second loop antenna 112 in-phase with equal amplitude through the first feeding output port 1221 and the second feeding output port 1222, respectively. Thus, the constant-amplitude in-phase feeding requirement between the unit antennas 110 is achieved with a simple parallel feeding structure, and a wide impedance band is provided.

With the loop antenna structure and the feeding network structure, the line of the second feeding output port 1222 connected to the second feeding input/output port 1121 of the second loop antenna 112 intersects the second ground 1122 of the second loop antenna 112. To avoid the second ground 1122, the present embodiment provides the second feed output port 1222 on the other side of the dielectric plate 20.

Specifically, the dielectric plate 20 includes first and second opposed surfaces. The printed array antenna 11 and the main body portion of the printed feed network 12 are disposed on a first surface of the dielectric plate 20. The main body portion of the printed feed network 12 includes a power divider 123, a feed input port 121, and a first feed output port 1221. Fig. 2 is a schematic diagram of a second surface structure of the printed antenna 10 according to an embodiment of the application. The second feeding output port 1222 is disposed on the second surface of the dielectric plate 20, one side of the second feeding output port 1222 is connected to the main body of the printed feeding network 12 through the first metallized via 131, and is connected to the second output end of the power divider 123, and the other side is connected to the second feeding input end 1121 of the second loop antenna 112 through the second metallized via 132, so as to avoid the second grounding end 1122 of the second loop antenna 112.

Fig. 4 is a schematic structural diagram of another embodiment of a printed antenna according to the present application. The printed antenna 10 in fig. 4 differs from the printed antenna 10 in fig. 1 in that the printed antenna 10 in fig. 4 further comprises a third loop antenna 113. The third loop antenna 113 includes a third feed input 1131 and a third ground 1132. The third loop antenna 113 has the same structure as the first loop antenna 111, and thus will not be described again.

The printed feed network 12 may feed the first loop antenna 111, the second loop antenna 112, and the third loop antenna 113 by series-parallel hybrid feeding. Specifically, the printed feed network 12 further includes a third feed output port 1223 and the radio frequency circuit board 30 further includes a third ground point 323. The third feed output port 1223 is connected to the third feed input 1131 and the third ground 1132 is connected to the third ground point 323. Here, taking the power divider 123 of the printing feed network 12 as a T-shaped power divider as an example, an input end of the power divider 123 is connected to the feed input port 121, a first output end of the power divider 123 is connected to the first feed output port 1221, and a second output end of the power divider 123 is connected to the second feed output port 1222 and the third feed output port 1223. I.e. the third feeding output port 1223 is located on the same side of the power divider 123 as the second feeding output port 1222. Thus, the printed feed network 12 enables series-parallel hybrid feeding of the first loop antenna 111, the second loop antenna 112, and the third loop antenna 113. Namely, the second loop antenna 112 and the third loop antenna 113 are fed in series, and the first loop antenna 111 is fed in parallel with the second loop antenna 112 and the third loop antenna 113. The series-parallel hybrid feeding can have the advantages of both series feeding and parallel feeding, that is, the printed feeding network 12 structure of the series-parallel hybrid feeding form has the advantages of relatively simplicity, wider impedance band, lower power consumption, smaller area, shorter feeding line, and the like.

To avoid the second ground 1122 of the second loop antenna 112 and the third ground 1132 of the third loop antenna 113, the second feed output port 1222 and the third feed output port 1223 may be disposed on the second surface of the dielectric plate 20. There are various ways in which the printed feed network 12 bypasses the second ground 1122 and the third ground 1132. For example, as shown in fig. 5, fig. 5 is a schematic structural diagram of an embodiment of the printed antenna in fig. 4 from a second surface perspective of the dielectric plate. A series feed 124 in the printed feed network 12 that communicates with the second feed output port 1222 and the third feed output port 1223 may be provided on the first surface of the dielectric plate 20. The manner in which the second feed output port 1222 is turned away from the second ground 1122 of the second loop antenna 112 is described above, and thus will not be described in detail herein. The printed feed network 12 also includes, for example, a third metallized via 133 and a fourth metallized via 134. One end of the series feed line 124 is connected to the second feed output port 1222, the other end of the series feed line 124 is connected to one end of the third feed output port 1223 through the third metallized via 133, and the other end of the third feed output port 1223 is connected to the third feed input 1131 of the third loop antenna 113 through the fourth metallized via 134. Therefore, the third feeding output port 1223 is prevented from avoiding the third grounding end 1132, the circuit is simple, and the manufacturing is easy.

Also for example, as shown in fig. 6, fig. 6 is a schematic structural view of another embodiment of the printed antenna of fig. 4 from a second surface perspective of the dielectric sheet. A series feed 124 in the printed feed network 12 that communicates with the second feed output port 1222 and the third feed output port 1223 may be provided on the second surface of the dielectric plate 20. In this embodiment, the series feed line 124 includes a second feed output port 1222 and a third feed output port 1223, and one end side of the series feed line 124 is the second feed output port 1222 and the other end side is the third feed output port 1223. The printed feed network 12 includes, for example, a fifth metallized via 135, a sixth metallized via 136, and a seventh metallized via 137. One end of the series feed line 124 is connected to the second output end of the power divider 123 through a fifth metallized via hole, and the other end of the series feed line 124 is connected to the third feed input end 1131 of the third loop antenna 113 through a seventh metallized via hole. A sixth metallized via 136 is located between the fifth metallized via 135 and the seventh metallized via 137 for connecting the series feed 124 with the second feed input 1121 of the second loop antenna 112, i.e., connecting the second feed output port 1222 and the second feed input 1121. Thus, there are relatively few metallized vias, which can reduce manufacturing complexity.

When the number of unit antennas 110 of the printed array antenna 11 is greater than 3, the printed feed network 12 may be a series-parallel mixed feed of a plurality of unit antennas 110 in the form of fig. 3. For example, the printed array antenna 11 further includes a fourth loop antenna (not shown), and the printed feed network 12 may adopt a structure in which three of the fourth loop antenna, the second loop antenna 112, and the third loop antenna 113 are fed in parallel with the first loop antenna 111, and the fourth loop antenna is fed in series with the second loop antenna 112 and the third loop antenna 113. Alternatively, the printed feed network 12 may also adopt a structure in which a fourth loop antenna is fed in series with the first loop antenna 111, and the fourth loop antenna, the first loop antenna 111, and both the second loop antenna 112 and the third loop antenna 113 are fed in parallel. In the case of including more unit antennas 110, the feeding form and the like, the spacing between each adjacent unit antennas 110 may satisfy the in-phase feeding requirement, which is not limited herein.

To verify the feasibility and effect of the printed antenna 10 of fig. 2 and 4, simulations were performed on a conventional loop printed antenna 10 and the printed antenna 10 of fig. 1 and 3, respectively. The dielectric sheet 20 is sized 145mm by 105mm. As shown in fig. 7, fig. 7 is a simulation diagram of the surface current distribution of the printed antenna of fig. 4. The 3 unit antennas 110 in fig. 4 are all set to 1 wavelength mode, and it can be seen that the loop antenna body has two current phase reversals, and three loop antenna current distributions satisfy the in-phase radiation condition, which indicates that the spacing of the three loop antennas meets the requirement of in-phase radiation.

As shown in fig. 8, fig. 8 is a comparison of different printed antenna horizontal patterns. The pattern, also called radiation pattern, refers to a pattern in which the relative field strength (normalized modulus) of the radiation field varies with direction at a distance from the antenna, and is usually represented by two perpendicular planar patterns in the maximum radiation direction of the antenna. Among other things, patterns of the pattern may include horizontal omni-directional, horizontal directional, and vertical coverage. It can be seen that as the number of unit antennas 110 increases, the 360 ° average gain of the radiation level of the printed antenna 10 becomes high and the out-of-roundness decreases. The average gain of the conventional loop printed antenna 10 was 0.39dB (out-of-roundness 20 dB), the printed antenna 10 in fig. 2 had a beamwidth of 2.17dBi (out-of-roundness 9.3 dB), and the printed antenna 10 in fig. 4 had a beamwidth of 3.54dBi (out-of-roundness 9.7 dB). The average gain in horizontal plane within half power beamwidth is: the average gain of the conventional loop printed antenna was 3.13dBi over 244 ° of beamwidth, the average gain of the printed antenna in fig. 2 was 4.37dBi over 225 ° of beamwidth, and the average gain of the printed antenna in fig. 4 was 5.82dBi over 227 ° of beamwidth.

The printed antenna 10 in fig. 2 was subjected to physical processing according to the dimensions of the simulation model (145 mm x 105 mm) and tested. As shown in fig. 9, fig. 9 is a diagram comparing the simulation of the printed antenna in fig. 2 with the horizontal pattern of the real object. It can be seen that the horizontal plane test pattern gain of the printed antenna 10 in fig. 2 is substantially identical to the simulation result, the maximum gain is 5.3dB, the out-of-roundness is 8.5dB, and the average gain difference is 0.4dB, mainly from the feeder loss and the difference between the material parameters of the actual board and the simulation.

The unit antenna 110 may be a printed dipole antenna, in addition to a loop antenna. Compared with the traditional dipole antenna, the printed dipole antenna has smaller volume, lighter weight and easy integration; on the other hand, the printing is smaller in size, lighter in weight and easy to integrate on the one hand; on the other hand, the printed dipole antenna has the advantages of relatively wide bandwidth, stable radiation direction and the like.

Fig. 10 is a schematic structural view of a printed antenna according to another embodiment of the present application, as shown in fig. 10 and 11; fig. 11 is a schematic structural view of the printed antenna of fig. 10 as seen from the second surface of the dielectric plate. As shown in fig. 10 and 11, the printed array antenna 11 includes a first dipole antenna 114 and a second dipole antenna 115 as an example. The first dipole antenna 114 includes a first dipole radiating arm 1141, a second dipole radiating arm 1142, a first L-shaped coupling feed line 1143, a first feed input terminal 1144, a first ground terminal 1145, and a second ground terminal 1146. The second dipole antenna 115 includes a third dipole radiating arm 1151, a fourth dipole radiating arm 1152, a second L-shaped coupling feed line 1153, a second feed input 1154, a third ground 1155, and a fourth ground 1156. The first L-shaped coupling feed line 1143 and the printed feed network 12 are disposed on a first surface of the dielectric plate 20, and the first dipole radiating arm 1141 and the second dipole radiating arm 1142 are disposed on a second surface of the dielectric plate 20. The first L-shaped coupling feed line 1143 is used for balanced feeding of the first dipole radiating arm 1141 and the second dipole radiating arm 1142, i.e., the first L-shaped coupling feed line 1143 can implement conversion from unbalanced feed to balanced feed and impedance transformation. The second dipole antenna 115 is identical to the first dipole antenna 114, and therefore will not be described in detail.

The first dipole radiating arm 1141 and the second dipole radiating arm 1142 have the same shape and structure, and a gap is arranged in the middle, and the first dipole radiating arm 1141 and the second dipole radiating arm 1142 are arranged in a mirror symmetry manner. The printed dipole antenna may be generally T-shaped in shape, with the first dipole radiating arm 1141 including a first portion 11411 parallel to the X-direction in fig. 10 and a second portion 11412 parallel to the Y-direction in fig. 10. The second dipole radiating arm 1142 is similar. The first portion 11411 of the first dipole radiating arm and the first portion 11421 of the second dipole radiating arm may be arranged co-linearly, thereby forming a dipole pair for facilitating polarization.

The first grounding end 1145 is located at an end of the first dipole radiating arm 1141 near the rf circuit board 30, and the second grounding end 1146 is located at an end of the second dipole radiating arm 1142 near the rf circuit board 30. The third ground 1155 is located at an end of the third dipole radiating arm 1151 adjacent to the rf circuit board 30, and the fourth ground 1156 is located at an end of the fourth dipole radiating arm 1152 adjacent to the rf circuit board 30. The radio frequency circuit board 30 includes a first ground point 321, a second ground point 322, a third ground point 323, and a fourth ground point 324. The first ground 1145 to the fourth ground 1156 are connected to the first ground 321 to the fourth ground 324 of the rf circuit board 30 one by one.

As shown in fig. 10, the first L-shaped coupling feed line 1143 includes a first portion 11431 parallel to the X-direction, the first portion 11431 of the first L-shaped coupling feed line being adjacent to the first portion 11411 of the first dipole radiating arm 1141 and the first portion 11421 of the second dipole radiating arm. One end of the first portion 11431 of the first L-shaped coupling feeder is connected to the second portion 11432 parallel to the Y direction, and the other end of the first portion 11431 of the first L-shaped coupling feeder is connected to the third portion 11433 parallel to the Y direction. The first L-shaped coupling feeder 1143 has an inverted L shape. The first feed input 1111 is located at an end of the second portion 11432 of the first L-shaped coupling feed line remote from the first portion 11431 of the first L-shaped coupling feed line. The second L-shaped coupling feeder 1153 is identical to the first L-shaped coupling feeder 1143, and thus will not be described again.

The first feed input 1144 is located at an end of the second portion 11432 of the first L-shaped coupling feed line adjacent to the radio frequency circuit board 30, and the second feed input 1154 is located at an end of the second portion 11432 of the second L-shaped coupling feed line 1153 adjacent to the radio frequency circuit board 30.

As shown in fig. 10, the feed output ports of the printed feed network 12 specifically include, for example, a first feed output port 1221 and a second feed output port 1222. The first feed output port 1221 is connected to the first feed input 1144 and the second feed output port 1222 is connected to the second feed input 1154. Thus, a feed signal is input from the first feed input 1144 to the first L-shaped coupling feed line 1143, so that the first L-shaped coupling feed line 1143 can excite the first dipole radiating arm 1141 and the second dipole radiating arm 1142. The feeding signal is inputted to the second L-shaped coupling feeder line 1153 from the second feeding input terminal 1154, so that the second L-shaped coupling feeder line 1153 can excite the third dipole radiating arm 1151 and the fourth dipole radiating arm 1152.

Specifically, the projection of the second portion 11432 of the first L-shaped coupling feed line in the thickness direction of the dielectric plate 20 overlaps the second portion 11412 of the first dipole radiating arm, which are parallel to each other across the dielectric plate 20, so that the first L-shaped coupling feed line 1143 can couple-feed the first dipole radiating arm 1141. The projection of the third portion 11433 of the first L-shaped coupling feed line in the thickness direction of the dielectric plate 20 overlaps the second portion 11422 of the second dipole radiation arm, and the two are parallel to each other across the dielectric plate 20. The first dipole antenna 114 may also include an eighth metallized via 138. The eighth metallized via 138 is used to connect the second dipole radiating arm 1142 and the first L-shaped coupling feed line 1143 of the first dipole antenna 114, thereby forming a balun structure capable of increasing the impedance bandwidth.

The printed feed network 12 may feed the first dipole antenna 114 and the second dipole antenna 115 by way of parallel feeding. The printed feed network 12 of the parallel feed structure is described with reference to the above related descriptions, and will not be repeated here. Unlike the printed feed network 12 in fig. 1, since the ground terminals of the unit antennas 110 are all located on the second surface of the dielectric plate 20 in this embodiment, the printed feed network 12 as a whole can be located on the first surface of the dielectric plate 20, and the ground terminals do not need to be avoided by means of metallized vias, so that the printed feed network 12 is simpler in structure.

Fig. 12 is a schematic structural diagram of a printed antenna according to another embodiment of the present application. The printed array antenna 11 of the present embodiment is different from the printed antenna 10 in fig. 10 and 11 in that the printed array antenna 11 further includes a third dipole antenna 116. The third dipole antenna 116 has the same structure as the first dipole antenna 114, and thus will not be described herein.

The printed feed network 12 may feed the first dipole antenna 114, the second dipole antenna 115, and the third dipole antenna 116 by series-parallel hybrid feeding. The printed feed network 12 of the series-parallel hybrid feed structure is described with reference to the above related descriptions, and thus will not be described in detail herein. Also, unlike the printed feed network 12 of fig. 3, since the ground terminals of the unit antennas 110 are all located on the second surface of the dielectric plate 20 in this embodiment, the printed feed network 12 as a whole can be located on the first surface of the dielectric plate 20 without avoiding the ground terminals by means of metallized vias.

When the number of unit antennas 110 of the printed array antenna 11 is greater than 3, the printed feed network 12 may be a series-parallel mixed feed of a plurality of unit antennas 110 in the form of fig. 3. For example, the printed array antenna 11 further includes a fourth dipole antenna, and the printed feed network 12 may adopt a structure in which the fourth dipole antenna, the second dipole antenna 115, and the third dipole antenna 116 are fed in parallel with the first dipole antenna 114, and the fourth dipole antenna is fed in series with the second dipole antenna 115 and the third dipole antenna 116. Alternatively, the printed feed network 12 may also employ a structure in which a fourth dipole antenna is fed in series with the first dipole antenna 114, and both the fourth dipole antenna, the first dipole antenna 114, and both the second dipole antenna 115 and the third dipole antenna 116 are fed in parallel. In the case of including more unit antennas 110, the feeding form and the like, the spacing between each adjacent unit antennas 110 may satisfy the in-phase feeding requirement, which is not limited herein.

To verify the feasibility and effect of the printed antenna 10 of fig. 10 and 12, simulations were performed on a conventional dipole printed antenna and the printed antenna 10 of fig. 10 and 12, respectively. As shown in fig. 13 and 14, fig. 13a is a three-dimensional pattern of a conventional dipole printed antenna; FIG. 13b is a three-dimensional pattern of the printed antenna of FIG. 9; FIG. 13c is a three-dimensional pattern of the printed antenna of FIG. 10; fig. 14 is a comparison of different printed antenna horizontal patterns. It can be seen that as the number of unit antennas 110 increases, the vertical plane beam becomes narrower, the horizontal plane beam becomes wider, and the 360 ° average gain of the horizontal plane of the printed array antenna 11 becomes higher. The average gain of the conventional dipole printed antenna 10 is-0.13 dB, the average gain of the printed antenna 10 in fig. 10 is 1.77dBi, and the average gain of the printed antenna 10 in fig. 12 is 2.78dBi. The average gain in horizontal plane within half power beamwidth is: the average gain of a conventional dipole printed antenna over a beam width of 202 deg. is 2.18dBi, the average gain of the printed antenna in fig. 10 over a beam width of 211 deg. is 4.19dBi, and the average gain of the printed antenna in fig. 12 over a beam width of 224 deg. is 4.85dBi.

The printed array antenna 11 is formed by combining the feed structure and the series feed, the printed antenna 10 with wide wave beam and high gain can be realized, and the printed array antenna is integrated with a PCB cable-free antenna, and has simple assembly and low cost, thereby solving the congenital problems of small gain, quick gain fading, inconsistent coverage and inferior performance of the conventional printed directional antenna and external high gain antenna.

The printed antenna of each embodiment provided by the application can be applied to communication equipment, so that the wireless coverage capability under different scenes is greatly improved. Fig. 15 is a schematic structural diagram of an embodiment of a communication device according to the present application.

In this embodiment, the communication device 150 includes a housing 151, a radio frequency circuit board 152, and a printed antenna 153 in any of the embodiments described above. The radio frequency circuit board 152 and the printed antenna 153 are disposed within the housing 151. The printed antenna 153 is connected to a radio frequency circuit board 152, and the radio frequency circuit board 152 is used for providing a feeding signal for the printed antenna 153.

Specifically, the radio frequency circuit board 152 may include a feeding point (not shown) and a ground point (not shown). The printed antenna 153 includes a printed array antenna (not shown) and a printed feed network (not shown). The printed array antenna includes N unit antennas (not shown), N being an integer greater than or equal to 2. Each unit antenna comprises a feed input terminal and a ground terminal. The printed feed network includes a feed input port and N feed output ports. The grounding end of each unit antenna is connected with the grounding point of the radio frequency circuit board. The N feed output ports of the printed feed network are respectively connected with the feed input ends of the N unit antennas one by one, namely, each feed output port of the printed feed network is respectively connected with the feed input end of one unit antenna, and the feed output ports are in one-to-one correspondence with the feed input ends. The feed input port of the printed feed network is connected with the feed point of the radio frequency circuit board. Thus, the printed feed network receives the feed signal transmitted by the radio frequency circuit board 152 through the feed point and delivers the feed signal to the N unit antennas to excite the N unit antennas. Therefore, the communication equipment 150 with the printed antenna 153 and the radio frequency circuit board 152 provided by the application has larger horizontal gain, higher wireless coverage capability and improved wireless propagation performance of the communication equipment.

Network device 150 is, for example, a home gateway, a wireless AP, or other wireless device requiring beam-level omni-directional coverage.

And (3) home gateway: is a network device located inside a modern home, and has the function of enabling a home user to connect to the Internet, enabling various intelligent devices located in the home to be served by the Internet, or enabling the intelligent devices to communicate with each other. In short, the home gateway is a bridge for networking various intelligent devices inside a home and for interconnecting from inside the home to an external network. From a technical point of view, the home gateway implements bridging/routing, protocol conversion, address management and conversion inside the home and from inside to outside, assumes the role of a firewall, and provides possible VoIP/Video over IP and other services.

Wireless AP: an AP (Access Point), a wireless Access node, a session Point, or an Access bridge, is a generic name that includes not only a simple wireless Access Point (wireless AP), but also a wireless router (including a wireless gateway and a wireless bridge).

It should be noted that the above embodiments are only for illustrating the technical solution of the present application, and are not limiting. Although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. The utility model provides a print antenna, its characterized in that, print antenna print on the dielectric plate, still be provided with the radio frequency circuit board on the dielectric plate, the radio frequency circuit board with print antenna coplanar integrated into one piece, the radio frequency circuit board is used for print antenna provides the feed signal, print antenna includes:

the printed array antenna is used for providing horizontal omnidirectional radiation and comprises N unit antennas, each unit antenna comprises a feed input end and a grounding end, the grounding end is connected with a grounding point of the radio frequency circuit board, and N is an integer greater than or equal to 2;

the printed feed network comprises feed input ports and N feed output ports, wherein the feed input ports are connected with the feed points of the radio frequency circuit board, and the N feed output ports are connected with the feed input ends of the N unit antennas one by one.

2. The printed antenna of claim 1, wherein the printed feed network is configured to feed the N unit antennas in parallel or in a series-parallel hybrid.

3. A printed antenna according to claim 1 or 2, wherein each of the unit antennas is a loop antenna.

4. A printed antenna according to claim 3, wherein the printed array antenna comprises a first unit antenna and a second unit antenna, the printed feed network being for feeding the first unit antenna and the second unit antenna in parallel.

5. The printed antenna of claim 4, wherein the printed array antenna is disposed on a first surface of the dielectric plate, the printed feed network comprises a first feed output port and a second feed output port, the feed input port and the first feed output port of the printed feed network are disposed on the first surface of the dielectric plate, the first feed output port is connected to the feed input end of the first unit antenna, the second feed output port is disposed on a second surface of the dielectric plate through a first metallized via, the second feed output port is connected to the feed input end of the second unit antenna through a second metallized via to avoid the ground terminal of the second unit antenna, and the first surface and the second surface of the dielectric plate are opposite.

6. The printed antenna of claim 1 or 2, wherein each of the unit antennas is a printed dipole antenna.

7. The printed antenna of claim 6, wherein each of the unit antennas comprises a first dipole radiating arm, a second dipole radiating arm, and an L-shaped coupling feed line for balanced feeding of the first dipole radiating arm, the second dipole radiating arm, the first dipole radiating arm comprising a first ground terminal, the second dipole radiating arm comprising a second ground terminal, the first and second ground terminals being connected to the radio frequency circuit board, the L-shaped coupling feed line comprising the feed input terminal.

8. The printed antenna of claim 7, wherein the L-shaped coupling feed line and the printed feed network are disposed on a first surface of the dielectric plate, the first dipole radiating arm and the second dipole radiating arm are disposed on a second surface of the dielectric plate, and the first surface and the second surface of the dielectric plate are opposite.

9. The printed antenna of any of claims 1-8, wherein the N unit antennas are arranged in a line, and a spacing between any two adjacent ones of the N unit antennas satisfies an in-phase requirement.

10. A communication device comprising a housing, a radio frequency circuit board and a printed antenna according to any one of claims 1 to 9, the printed antenna and the radio frequency circuit board being arranged in the housing, the printed antenna being connected to the radio frequency circuit board, the radio frequency circuit board being arranged to provide a feed signal for the printed antenna.