Antenna and communication apparatus

An antenna includes: a dielectric layer having first and second surfaces opposite to each other; a radiating layer on the first surface, and having therein a slit; a first shielding layer on the second surface, and being electrically connected to the radiating layer; a first insulating layer on an upper side of the radiating layer; and a switch unit on an upper side of the first insulating layer, and corresponding to the slit. Each switch unit includes: a first electrode, a second insulating layer, a connecting portion, and a second electrode on the first insulating layer sequentially. Orthogonal projections of the first and second electrodes on the dielectric layer overlap each other. The connecting portion is connected to the second electrode to form a gap between the first and second electrodes. Orthogonal projections of the second electrode and a corresponding slit on the dielectric layer overlap each other.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a National Phase Application filed under 35 U.S.C. 371 as a national stage of PCT/CN2021/074275 filed on Jan. 29, 2021, the content of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to the field of communication technology, and in particular, to an antenna and a communication apparatus.

BACKGROUND

A radial line slot antenna has the advantages of small loss of a waveguide slot array, simple structure of a microstrip antenna, and low profile, and thus, is widely applied to millimeter wave microwave systems. Generally, the radial line slot antenna is composed of an upper metal plate and a lower metal plate that have therebetween a distance less than ½ wavelengths, to form a radial waveguide, and designed slots are formed in the upper metal plate, so that any polarization mode or radiation characteristic can be realized.

SUMMARY

Embodiments of the present disclosure provide an antenna and a communication apparatus.

In a first aspect, embodiments of the present disclosure provide an antenna, which includes:a dielectric layer having a first surface and a second surface opposite to each other in a thickness direction of the dielectric layer;a radiating layer on the first surface of the dielectric layer, and having therein at least one slit;a first shielding layer on the second surface of the dielectric layer, and being electrically connected to the radiating layer;wherein the antenna further includes:a first insulating layer on a side of the radiating layer distal to the first surface of the dielectric layer;at least one switch unit on a side of the first insulating layer distal to the dielectric layer, and being in one-to-one correspondence with the at least one slit; andeach switch unit includes: a first electrode, a second insulating layer, at least one connecting portion, and a second electrode that are sequentially arranged in a direction away from the first insulating layer, wherein an orthogonal projection of the first electrode on the dielectric layer and an orthogonal projection of the second electrode on the dielectric layer overlap each other, the at least one connecting portion is connected to the second electrode to form a certain gap between the second electrode and the first electrode, and the orthogonal projection of the second electrode on the dielectric layer and an orthogonal projection of a corresponding slit on the dielectric layer at least partially overlap each other.

In an embodiment, the orthogonal projection of the second electrode on the dielectric layer covers a center of the orthogonal projection of the corresponding slit on the dielectric layer.

In an embodiment, the first electrode includes a first sub-electrode and a second sub-electrode, and orthogonal projections of the first sub-electrode and the second sub-electrode on the dielectric layer are respectively on both sides, which are along a lengthwise direction of the orthogonal projection of the corresponding slit on the dielectric layer, of the orthogonal projection of the corresponding slit on the dielectric layer, and the at least one connecting portion is on a portion of the second insulating layer on at least one of the first sub-electrode and the second sub-electrode of each switch unit.

In an embodiment, each switch unit includes two connecting portions, the two connecting portions are respectively connected to two opposite ends of the second electrode in a lengthwise direction of the second electrode, and the lengthwise direction of the second electrode in each switch unit intersects with a lengthwise direction of the slit corresponding to the switch unit.

In an embodiment, each switch unit includes one connecting portion connected to one end of the second electrode in a lengthwise direction of the second electrode, and the lengthwise direction of the second electrode in each switch unit intersects with a lengthwise direction of the slit corresponding to the switch unit.

In an embodiment, the dielectric layer includes a first sub-dielectric layer and a second sub-dielectric layer, a surface of the first sub-dielectric layer distal to the second sub-dielectric layer serves as the first surface of the dielectric layer, a surface of the second sub-dielectric layer distal to the first sub-dielectric layer serves as the second surface of the dielectric layer, the antenna further includes a second shielding layer between the first sub-dielectric layer and the second sub-dielectric layer, and an edge of an orthogonal projection of the second shielding layer on the first sub-dielectric layer and a corresponding edge of an orthogonal projection of the first shielding layer on the first sub-dielectric layer have a certain distance therebetween.

In an embodiment, an orthogonal projection of a center of the first shielding layer on the first sub-dielectric layer and an orthogonal projection of a center of the second shielding layer on the first sub-dielectric layer overlap each other.

In an embodiment, the at least one slit includes a plurality of slits, and the plurality of slits are arranged to form one of the following:a spiral shape;concentric circles; anda linear shape.

In an embodiment, the antenna further includes a feeding element for feeding an electromagnetic wave signal into the dielectric layer, and a feeding point of the feeding element is at a center of the radiating layer.

In an embodiment, the dielectric layer includes a material of glass.

In a second aspect, embodiments of the present disclosure provide a communication apparatus, which includes the antenna according to any one of the foregoing embodiments.

DETAILED DESCRIPTION

To enable one or ordinary skill in the art to better understand technical solutions of the present disclosure, the present disclosure will be further described in detail below with reference to the accompanying drawings and exemplary embodiments.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which the present disclosure belongs. The terms “first”, “second”, and the like used in the present disclosure are not intended to indicate any order, quantity, or importance, but rather are used for distinguishing one element from another. Further, the term “a”, “an”, “the”, or the like used herein does not denote a limitation of quantity, but rather denotes the presence of at least one element. The term of “comprising”, “including”, or the like, means that the element or item preceding the term contains the element or item listed after the term and its equivalent, but does not exclude other elements or items. The term “connected”, “coupled”, or the like is not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect connections. The terms “upper”, “lower”, “left”, “right”, and the like are used only for indicating relative positional relationships, and when the absolute position of an object being described is changed, the relative positional relationships may also be changed accordingly.

It should be noted that a structure of an antenna according to an embodiment of the present disclosure includes, but is not limited to, a cylinder, a rectangular parallelepiped, a cube, or the like. In the following description of an embodiment, the structure of a slot antenna is exemplified as a cylinder. In an embodiment of the present disclosure, a material of a dielectric layer of the slot antenna includes, but is not limited to, glass, i.e., the dielectric layer may be made of glass. In fact, the material of the dielectric layer may alternatively be any insulating material capable of forming a structure with a flat surface, such as quartz, polyimide, transparent optical adhesive, or the like. Further, a dielectric constant of the dielectric layer is not limited, and an adopted thickness of the dielectric layer depends on the dielectric constant and an operating frequency of the antenna. In the following embodiments, description will be made by taking an example in which the dielectric layer is a glass dielectric layer, but this is not intended to limit the scope of the embodiments of the present disclosure.

In a first aspect, an embodiment of the present disclosure provides an antenna, andFIG.1is a schematic diagram showing the antenna according to the present embodiment.FIG.2is a top view of the antenna shown inFIG.1.FIG.3is a schematic diagram showing a turn-on state of a switch unit60according to the present embodiment, andFIG.4is a schematic diagram showing a turn-off state of the switch unit60according to the present embodiment. As shown inFIGS.1to4, the antenna includes a dielectric layer10, a first shielding layer30, a radiating layer20, a first insulating layer61, and at least one switch. The dielectric layer10includes a first surface and a second surface opposite to each other, the first surface being an upper surface of the dielectric layer10inFIG.1, and the second surface being a lower surface of the dielectric layer10inFIG.1. The radiating layer20is arranged on the first surface of the dielectric layer10, and is provided with at least one slit (or slot)21therein. The first shielding layer30is disposed on the second surface of the dielectric layer10, and is electrically connected to the radiating layer20disposed on the first surface of the dielectric layer10. One switch unit60in the present embodiment may be disposed corresponding to one slit21, and for example, switch units60are disposed to be in one-to-one correspondence with slits21. Each switch unit60may include a first electrode62, a second insulating layer63, at least one connecting portion64, and a second electrode65, which are sequentially disposed along a direction away from the first insulating layer61. For example, an orthogonal projection of the first electrode62on the dielectric layer10and an orthogonal projection of the second electrode65on the dielectric layer10overlap each other. Each connecting portion64is connected to the second electrode65such that a certain gap (or distance) exists between the second electrode65and the first electrode62. An orthogonal projection of the second electrode65on the dielectric layer10at least partially overlaps an orthogonal projection of a corresponding slit21on the dielectric layer10. Optionally, the antenna including slits21(i.e., slot antenna) further includes a feeding element50and the like, and the feeding element50is for feeding an electromagnetic wave into the dielectric layer10through the first shielding layer30.

It should be noted that, the first shielding layer30and the radiating layer20may be electrically connected to each other through a through hole penetrating through an edge region of the dielectric layer10. The number of through holes40may be two or more, and the two or more through holes are spaced apart from each other.

Since one switch unit60is disposed on each slit21of the antenna according to the present embodiment, and a certain gap exists between the first electrode62and the second electrode65of each switch unit60, when no voltage is applied across the first electrode62and the second electrode65, the switch unit60is in a turn-on state as shown inFIG.3, and a microwave signal fed into the dielectric layer by the feeding element50may be radiated out of the dielectric layer through the slit21. When a direct current (DC) bias voltage is applied across the first electrode62and the second electrode65, the second electrode65is pulled down to a surface of the corresponding slit21under the action of static electricity, and at this time, the switch unit60is in a turn-off state as shown inFIG.4. In this case, a microwave signal fed into the dielectric layer by the feeding element50cannot be radiated out of the dielectric layer, i.e., the switch serves as a shielding electrode. In addition, when the antenna includes a plurality of slits21and a plurality of switch units60, a direct current bias voltage may be selectively applied across the first electrodes62and the second electrodes65of some of the switch units60, so that a microwave signal may be radiated out of the dielectric layer through some of the slits21, but cannot be radiated out of the dielectric layer through other of the slits21, thereby adjusting a radiation direction of the microwave signal.

In some examples, the orthogonal projection of the second electrode65of each switch unit60on the dielectric layer10covers a center of the orthogonal projection of the corresponding slit21on the dielectric layer10. In this case, when a direct current bias voltage is applied across the first electrode62and the second electrode65of each switch unit60, the second electrode65is driven by an electrostatic force to cover the slit21to shield a microwave signal. It should be noted that, in general, the orthogonal projection of the second electrode65on the dielectric layer10may not completely cover the orthogonal projection of the corresponding slit21on the dielectric layer10. A length of each slit21is generally much greater than a width of the corresponding second electrode65.

In order to make the structure of each switch unit60according to an embodiment of the present disclosure more clear, two specific structures of each switch unit60will be described below.

In an example, each switch unit60is a MEMS (micro-electro-mechanical system) switch, and the first electrode62of each switch unit60includes a first sub-electrode621and a second sub-electrode622. Further, an orthogonal projection of the first sub-electrode621on the dielectric layer and an orthogonal projection of the second sub-electrode622on the dielectric layer10are arranged on both sides of a lengthwise direction of the orthogonal projection of the corresponding slit21on the dielectric layer10, respectively. Each switch unit60includes two connecting portions64, which are respectively connected to two opposite ends of the corresponding second electrode65in a lengthwise direction of the corresponding second electrode65. Further, one of the two connecting portions64is located on a portion of the second insulating layer63on the first sub-electrode621, and the other of the two connecting portions64is located on a portion of the second insulating layer63on the second sub-electrode622. In addition, an orthogonal projection of each of the first sub-electrode621and the second sub-electrode622on the dielectric layer10overlaps the orthogonal projection of the corresponding second electrode65on the dielectric layer10. In some examples, the two connecting portions64and the corresponding second electrode65have a one-piece structure, and may be formed through a single patterning process.

In another example,FIG.5is a schematic diagram showing a turn-on state of another switch unit60according to an embodiment of the present disclosure.FIG.6is a schematic diagram showing a turn-off state of the another switch unit60according to an embodiment of the present disclosure. The switch unit60shown inFIGS.5and6is substantially the same as that shown inFIG.3, except that the switch unit60shown inFIGS.5and6includes only one connecting portion64, and other structures thereof are the same as those of the switch unit60shown inFIG.3, thus detailed description thereof being omitted here.

It should be noted that, for the switch unit60shown inFIG.5, the second insulating layer63and the first electrode62(which is, in particular, the second sub-electrode622) may not be provided below an end, at which the connecting portion64is not provided, of the second electrode65. In this case, as long as a direct current bias voltage applied across the first sub-electrode621and the second electrode65is controlled so that the switch unit60may be in a turn-off state as shown inFIG.6, the second electrode65may also be driven by an electrostatic force to be in contact with the corresponding slit21in the radiating layer20.

In some examples,FIG.7is a schematic diagram showing another antenna according to an embodiment of the present disclosure. As shown inFIG.7, a dielectric layer10of the antenna includes a first sub-dielectric layer11and a second sub-dielectric layer12, and the antenna including slits21further includes a second shielding layer70disposed between the first sub-dielectric layer11and the second sub-dielectric layer12. Further, an edge of an orthogonal projection of the second shielding layer70on the first sub-dielectric layer11and a corresponding edge of an orthogonal projection of the first shielding layer30on the first sub-dielectric layer10have a certain distance therebetween. For example, a surface of the first sub-dielectric layer11distal to the second sub-dielectric layer12serves as the first surface of the dielectric layer10, and a surface of the second sub-dielectric layer12distal to the first sub-dielectric layer11serves as the second surface of the dielectric layer10. The radiating layer20is formed on the surface of the second sub-dielectric layer12distal to the first sub-dielectric layer11, and the first shielding layer30is formed on the surface of the first sub-dielectric layer11distal to the second sub-dielectric layer12. The radiating layer20and the first shielding layer30are connected to each other through a through hole40penetrating through the first sub-dielectric layer11and the second sub-dielectric layer12. The second shielding layer70may be formed on a surface of the first sub-dielectric layer11proximal to the second sub-dielectric layer12, or on a surface of the second sub-dielectric layer12proximal to the first sub-dielectric layer11. The following description will be made by taking an example in which the second shielding layer70is formed on the surface of the first sub-dielectric layer11proximal to the second sub-dielectric layer12. Each through hole40in the first sub-dielectric layer11and the second sub-dielectric layer12may be formed as a TGV (e.g., through glass via), and may be metalized, i.e., a metal conductive layer may be formed on an inner wall of each through hole40or a metal may be filled in each through hole40. The radiating layer20and the second shielding layer70may be formed on upper and lower surfaces of the first sub-dielectric layer11by using an electroplating process, respectively, and slits21in the radiating layer20may be formed by a patterning process. The first shielding layer30may be formed on a lower surface of the second sub-dielectric layer12by an electroplating process, and the first sub-dielectric layer11and the second sub-dielectric layer12may be aligned and assembled into a cell by a VAS (e.g., vacuum aligning technology), so as to result in a double-layer feeding layer with an extremely high alignment accuracy. The thickness of the dielectric layer10depends on the operating frequency of the antenna including slits21, and the thickness of the dielectric layer10is selected to be smaller for a higher operating frequency of the antenna including slits21. That is, in an embodiment of the present disclosure, a thickness of each of the first sub-dielectric layer11and the second sub-dielectric layer12of the dielectric layer10may be designed according to an operating frequency of the antenna including slits21. In an embodiment of the present disclosure, each of the first sub-dielectric layer11and the second sub-dielectric layer12may be single-layer glass or multi-layer glass.

In the antenna including slits21with such a structure, there is no electrical connection between the second shielding layer70and any through hole40, and the second shielding layer70mainly serves as making an electromagnetic wave fed into the dielectric layer10be distributed uniformly. Specifically, an electromagnetic wave fed by the feeding element50enters into the first sub-dielectric layer11, propagates from a center line of the first sub-dielectric layer11along a radial direction of the antenna including slits21, and then propagates to the second sub-dielectric layer12from an edge of the second shielding layer70. That is, the electromagnetic wave propagates from a center to an edge of the first sub-dielectric layer11, propagates from an edge to a center of the second sub-dielectric layer12, and then is radiated out of the dielectric layer through the slits21in the radiating layer20. In this way, the transmission and radiation of the electromagnetic wave is more uniform.

In some examples, the radiating layer20may have therein a plurality of slits21, and the plurality of slits21may be arranged in a plurality of loops (or turns or rings or circles). Further, the slits21in each loop are uniformly spaced apart from each other, and a distance between any adjacent two of the plurality of loops is a constant. As such, a electromagnetic wave radiated by the antenna including slits21according to an embodiment of the present disclosure is distributed uniformly. It should be noted that, as shown inFIG.2, in an embodiment of the present disclosure, the structure of the slot antenna is exemplified as a cylinder, and therefore, the slits21in each loop are arranged on a circle (or arranged to form a circle). If the slot antenna has a structure of a cube, the slits21in each loop may be arranged on a square (or arranged to form a square). Alternatively, as shown inFIG.2, the radiating layer20may have a shape of a circle, and the slits21in each loop are arranged on a circle (or arranged to form a circle), while a profile of an edge of the radiating layer20may be a square. That is, a shape of the profile of the antenna including slits21may be different from a shape of a radiation area, i.e., may be different from a shape formed by the arrangement of the slits21in each loop in the radiation area.

It should be noted that, a shape of each slit21is not limited in an embodiment of the present disclosure, and includes, but is not limited to, a linear shape or the like.

In addition, the plurality loops of slits21are concentrically arranged, and a feeding point of the feeding element50corresponds to a center of the plurality loops of slits21. Such an arrangement can result in more uniform radiation of an electromagnetic wave.

In some examples, the radiating layer20have therein a plurality of slits21, and the plurality of slits21are arranged in a spiral shape (or arranged to from a spiral shape). Further, a distance between any adjacent two of the plurality of slits21is constant along an arrangement direction of the plurality of slits21(or along a direction in which the plurality of slits21are arranged). It should be noted that, in a case where the plurality of slits21are arranged in a spiral shape, the arrangement direction of the plurality of slits21refers to a direction of a curve formed by successively connecting centers of the plurality of slits21together. As such, an electromagnetic wave radiated from the antenna including slits21according to the present embodiment is distributed uniformly.

In some embodiments, the feeding point of the feeding element50is located at a center of the first shielding layer30, which facilitates uniform radiation of an electromagnetic wave.

In some examples, the thickness of the dielectric layer10ranges from about 100 μm to about 10 mm, and depends on the dielectric constant of the dielectric layer10and the operating frequency of the antenna.

In some examples, the feeding element50may be a probe. An opening is disposed in the first shielding layer30, and a half-hole (or semi-hole) is formed in the dielectric layer10at a position corresponding to the opening. The probe is fed into the half-hole of the dielectric layer10through the opening in the first shielding layer30, and the feeding element50is connected to the first shielding layer30by welding.

For the antenna shown in each ofFIGS.1to7, since the slits21of the antenna are arranged to form concentric circles or a spiral shape, and the feeding element50feeds power upwards from the first shielding layer30, the antenna is a two-dimensional scanning antenna.FIG.8is a schematic diagram showing a simulation of one switch unit60in the antenna shown in each ofFIGS.1to7, and the result (which is optional) of the simulation is as follows. When the switch unit60is in a turn-on state, i.e., a certain gap exists between the first electrode62and the second electrode65, the antenna can achieve a gain of −7.89 dB. When the switch unit60is in a turn-off state, i.e., the first electrode62is in contact with the corresponding slit21in the radiating layer20, the antenna can achieve a gain of −15.88 dB. The result indicates that the radiation and shielding of a microwave can be achieved by controlling the state of the switch unit60.

In some examples,FIG.9is a top view showing another antenna according to an embodiment of the present disclosure, andFIG.10is a side view of the antenna shown inFIG.9. As shown inFIGS.9and10, the slits21of the antenna are arranged side by side on a straight line, and one switch unit60is arranged at a position corresponding to each of the slits21. The antenna is a one-dimensional scanning antenna, and a feeding element50of the antenna may be arranged at each of the left and right sides of the antenna. The arrows shown inFIGS.9and10illustrate a configuration of feeding a microwave into the antenna from the left side. A turn-on state and a turn-off state of each switch unit60may be realized in the same manner as described above, thereby realizing the radiation and shielding of a microwave.

In some examples, each of the first shielding layer30, the second shielding layer70, the radiating layer20, the first electrode62, the second electrode65, and the connecting portion64may be made of a material of metal, which in particular includes, but is not limited to, a low-resistance and low-loss metal such as copper, gold, silver, or the like, and may be manufactured by magnetron sputtering, thermal evaporation, electroplating, and/or the like.

In a second aspect, an embodiment of the present disclosure provides a communication apparatus, which includes the antenna according to any one of the foregoing embodiments. The communication apparatus can achieve the same advantages as those of the antenna, and detailed description thereof is omitted here.

It should be noted that the above embodiments are merely exemplary embodiments adopted to illustrate the principles of the present disclosure, and the present disclosure is not limited thereto. It will be apparent to one of ordinary skill in the art that various modifications and improvements may be made therein without departing from the spirit and scope of the present disclosure, and such modifications and improvements are also considered to fall within the scope of the present disclosure.