CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application claims priority to Chinese Patent Application No. 202110645287.3, filed June 10, 2021, the entire content of which is incorporated herein by reference as if set forth fully herein.

FIELD

[0002] The present disclosure relates to communication systems, and more specifically, to an antenna assembly and a feed element for an antenna

BACKGROUND

[0003] An antenna generally includes a radiator for emitting electromagnetic radiation, a reflector for redirecting the electromagnetic radiation to propagate substantially forward of the antenna, and a feed network for feeding the radiator. The feed network may include a feed line located in a stalk, a feed line located on a feed board, a feed line located in a phase shifter, and connection lines among these feed lines, etc. The stalk is located between the reflector and the radiator and is used to fix the radiator at a position with a specific distance in front of the reflector. The feed board is fixed on a front surface of the reflector and is used to feed one or more radiators. The phase shifter may be located in the rear of the reflector, and the phase shifter divides a received RF signal into a plurality of sub-components and applies a phase taper to the sub-components. As those skilled in the art know, by applying a phase taper to the sub components of an RF signal fed to different radiators in one column (or a plurality of columns), it is possible to apply an electronic down tilt to an antenna beam generated by the antenna, and this can be used to adjust the size of an area “covered” by the antenna beam. SUMMARY

[0004] According to a first aspect of the present disclosure, an antenna assembly is provided, comprising: a cross-dipole radiator, which has a generally flat first surface, a first slot and a second slot in the first surface that respectively extend along a first direction, and a third slot and a fourth slot in the first surface that respectively extend along a second direction that is perpendicular to the first direction; a conductive supporting member, which is configured to fix the cross-dipole radiator at a specific distance in front of a reflector; a first feed element, including a first power divider, and a first feed line, a second feed line, and a third feed line respectively coupled to an input end, a first output end, and a second output end of the first power divider, wherein the first feed line and the conductive supporting member form a first microstrip transmission line, the second feed line and the cross-dipole radiator form a second microstrip transmission line, and the third feed line and the cross-dipole radiator form a third microstrip transmission line, and the second feed line and the third feed line respectively cross the first slot and the second slot; and a second feed element, including a second power divider, and a fourth feed line, a fifth feed line, and a sixth feed line respectively coupled to an input end, a first output end, and a second output end of the second power divider, wherein the fourth feed line and the conductive supporting member form a fourth microstrip transmission line, the fifth feed line and the cross-dipole radiator form a fifth microstrip transmission line, and the sixth feed line and the cross-dipole radiator form a sixth microstrip transmission line, and the fifth feed line and the sixth feed line respectively cross the third slot and the fourth slot.

[0005] According to a second aspect of the present disclosure, a feed element for an antenna is provided, comprising: a power divider; a first feed line extending forward from a reflector of the antenna to be coupled to an input end of the power divider, the first feed line being configured to form a first microstrip transmission line with a conductive supporting member, wherein the conductive supporting member is configured to fix a radiator in front of the reflector; a second feed line extending from a first output end of the power divider parallel to a main surface of the radiator, the second feed line being configured to form a second microstrip transmission line with the radiator; and a third feed line extending from a second output end of the power divider parallel to the main surface of the radiator, the third feed line being configured to form a third microstrip transmission line with the radiator, wherein the second feed line and the third feed line excite the radiator through a first excitation position and a second excitation position of the radiator, respectively.

[0006] According to a third aspect of the present disclosure, a feed element for an antenna is provided, comprising: an input section, a first end of which is coupled to a phase shifter; and a feed line extending forward from a reflector of the antenna to be coupled to a line for exciting a radiator, the feed line being configured to form a first microstrip transmission line with a conductive supporting member, wherein the conductive supporting member is configured to fix the radiator at a specific distance in front of the reflector, wherein a second end of the input section is coupled to the feed line.

[0007] Other features and advantages of the present disclosure will be made clear by the following detailed description of exemplary embodiments of the present disclosure with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWING

[0008] Fig. l is a perspective view of an antenna assembly according to an embodiment of the present disclosure.

[0009] Fig. 2 is a side view of the antenna assembly shown in Fig. 1.

[0010] Fig. 3 is a perspective view of the antenna assembly shown in Fig. 1 from another viewing angle.

[0011] Fig. 4 is a top view of the antenna assembly shown in Fig. 1.

[0012] Fig. 5 is a perspective view of a radiating element in the antenna assembly shown in Fig. 1.

[0013] Fig. 6 is a perspective view of a feed element in the antenna assembly shown in

Fig. 1.

[0014] Fig. 7 is a side view of the feed element shown in Fig. 6.

[0015] Fig. 8 is a perspective view showing a connection between an input section of the feed element shown in Fig. 6 and a phase shifter.

[0016] Note, in the embodiments described below, the same signs are sometimes jointly used between different attached drawings to denote the same parts or parts with the same functions, and repeated descriptions thereof are omitted. In some cases, similar labels and letters are used to indicate similar items. Therefore, once an item is defined in one attached drawing, it does not need to be further discussed in subsequent attached drawings. [0017] For ease of understanding, the position, dimension, and range of each structure shown in the attached drawings and the like may not indicate the actual position, dimension, and range. Therefore, the present disclosure is not limited to the position, size, range, etc. disclosed in the attached drawings.

DETAILED DESCRIPTION

[0018] The present disclosure will be described below with reference to the attached drawings, which show several examples of the present disclosure. However, it should be understood that the present disclosure can be presented in many different ways and is not limited to the examples described below. In fact, the examples described below are intended to make the present disclosure more complete and to fully explain the protection scope of the present disclosure to those skilled in the art. It should also be understood that the examples disclosed in the present disclosure may be combined in various ways so as to provide more additional examples.

[0019] It should be understood that the terms used herein are only used to describe specific examples, and are not intended to limit the scope of the present disclosure. All terms used herein (including technical terms and scientific terms) have meanings normally understood by those skilled in the art unless otherwise defined. For brevity and/or clarity, well-known functions or structures may not be further described in detail.

[0020] As used herein, when an element is said to be “on” another element, “attached” to another element, “connected” to another element, “coupled”/“coupling” to another element, or “in contact with” another element, etc., the element may be directly on another element, attached to another element, connected to another element, coupled to another element, or in contact with another element, or an intermediate element may be present. In contrast, if an element is described “directly” “on” another element, “directly attached” to another element, “directly connected” to another element, “directly coupled”/“ directly coupling” to another element or “directly contacting” another element, there will be no intermediate elements. As used herein, when one feature is arranged “adjacent” to another feature, it may mean that one feature has a part overlapping with the adjacent feature or a part located above or below the adjacent feature.

[0021] In this Specification, elements, nodes or features that are “connected” together may be mentioned. Unless explicitly stated otherwise, “connected” means that one element/node/feature can be mechanically, electrically, logically or otherwise connected with another element/node/feature in a direct or indirect manner to allow interaction, even though the two features may not be directly connected. That is, “connected” means direct and indirect connection of components or other features, including connection using one or a plurality of intermediate components.

[0022] As used herein, spatial relationship terms such as “upper”, “lower”, “left”,

“right”, “front”, “back”, “high” and “low” can explain the relationship between one feature and another in the drawings. It should be understood that, in addition to the orientations shown in the attached drawings, the terms expressing spatial relations also comprise different orientations of a device in use or operation. For example, when a device in the attached drawings rotates reversely, the features originally described as being “below” other features now can be described as being “above” the other features”. The device may also be oriented by other means (rotated by 90 degrees or at other locations), and at this time, a relative spatial relation will be explained accordingly.

[0023] As used herein, the term “A or B” comprises “A and B” and “A or B”, not exclusively “A” or “B”, unless otherwise specified.

[0024] As used herein, the term “exemplary” means “serving as an example, instance or explanation”, not as a “model” to be accurately copied”. Any realization method described exemplarily herein may not be necessarily interpreted as being preferable or advantageous over other realization methods. Furthermore, the present disclosure is not limited by any expressed or implied theory given in the above technical field, background art, summary of the invention or specific embodiments.

[0025] As used herein, the word “basically” means including any minor changes caused by design or manufacturing defects, device or component tolerances, environmental influences, and/or other factors. The word “basically” also allows the gap from the perfect or ideal situation due to parasitic effects, noise, and other practical considerations that may be present in the actual realization.

[0026] In addition, for reference purposes only, “first”, “second” and similar terms may also be used herein, and thus are not intended to be limitative. For example, unless the context clearly indicates, the words “first”, “second” and other such numerical words involving structures or elements do not imply a sequence or order. [0027] It should also be understood that when the term “comprise/include” is used herein, it indicates the presence of the specified feature, entirety, step, operation, unit and/or component, but does not exclude the presence or addition of one or a plurality of other features, steps, operations, units and/or components and/or combinations thereof.

[0028] According to an embodiment of the present disclosure, a feed element is provided. The feed element is formed of sheet metal as a monolithic structure. The feed element may couple an output of a phase shifter (for example, a cavity phase shifter) to a corresponding radiator. In many conventional feed networks, feed cables are routed along (or form) the feed stalk of a radiating element, and these coaxial cables connect to a feed board printed circuit board (PCB) in order to feed the radiating element. The monolithic feed element according to an embodiment of the present disclosure may replace the feed cables and the feed board (as well as the connections therebetween) of the above-described conventional feed network. The feed element with the aforementioned configuration can avoid the use of cables and printed circuit boards, and thus may have reduced cost as compared to the above-described conventional feed network. In addition, since the feed element is formed of sheet metal as a monolithic structure, soldered connections that are provided between the feed cables and the feed board PCB in the conventional feed network are not needed when the feed networks according to embodiments of the present disclosure are used. This may result in improved passive intermodulation (PIM) performance and facilitate high transmission efficiency. According to an embodiment of the present disclosure, an antenna assembly including the aforementioned feed element is further provided.

[0029] Figs. 1 to 4 show an antenna assembly 100 according to an embodiment of the present disclosure. The antenna assembly 100 includes a radiating element, and a feed element 130 and a feed element 140 respectively formed by sheet metal as monolithic structures. Fig. 5 shows the radiating element in the antenna assembly 100. Figs. 6 and 7 show the feed element 130 and the feed element 140 in the antenna assembly 100. Fig. 8 shows a connection of the feed element 130 and the feed element 140 with a phase shifter.

[0030] The radiating element includes a cross-dipole radiator 110 and a conductive supporting member 120. In the illustrated embodiment, the cross-dipole radiator 110 has a symmetrical bowl shape. The cross-dipole radiator 110 may be implemented by sheet metal. The conductive supporting member 120 fixes the cross-dipole radiator 110 at a specific distance in front of a reflector 150. It should be noted that in the present disclosure, the “front” or "forward" direction refers to a direction that is substantially perpendicularly pointing to the radiator 110 from the reflector 150, and a direction to the “rear” refers to a direction opposite to the forward direction. The conductive supporting member 120 may have a hollow column shape. In the illustrated embodiment, the conductive supporting member 120 has a rectangular cross section.

A central portion of the cross-dipole radiator 110 has an opening 115 that has a shape that matches a shape of the front end of the conductive supporting member 120. The cross-dipole radiator 110 and the conductive supporting member 120 are formed as a monolithic structure.

The cross-dipole radiator 110 has a main surface that is generally flat and extends substantially parallel to the reflector 150. The cross-dipole radiator 110 further has slots 111 to 114 in the main surface. The slots 111 and 112 respectively extend to edges of the cross-dipole radiator 110 along a direction 171 on two opposite sides of the opening 115, and the slots 113 and 114 respectively extend to edges of the cross-dipole radiator 110 along a direction 172 on two opposite sides of the opening 115. The direction 171 and the direction 172 are perpendicular to each other. The direction 171 is inclined by +45° relative to a longitudinal axis 170 of the antenna assembly 100, and the direction 172 is inclined by or -45° relative to the longitudinal axis 170 of the antenna assembly 100.

[0031] The feed element 130 includes a power divider 131, a feed line 132, a feed line 133, and a feed line 134. At least most of the feed element 130 may be mounted forwardly of the reflector 150. In particular, the feed line 132 extends forwardly from the reflector 150 to be coupled to an input end of the power divider 131. The feed line 133 is coupled to a first output end of the power divider 131 and extends from the first output end of the power divider 131 parallel to a main surface of the cross-dipole radiator 110. The feed line 134 is coupled to a second output end of the power divider 131 and extends from the second output end of the power divider 131 parallel to the main surface of the cross-dipole radiator 110. The feed line 133 and the feed line 134 respectively extend symmetrically from the power divider 131. Each feed line includes an inductive element 1331 extending from the power divider 131 and a capacitive element 1332 extending from the inductive element 1331. The feed line 133 and the feed line 134 extend until they cross the slot 111 and the slot 112 respectively (for example, to make the capacitive element 1332 of each feed line cross the slot), so as to excite the cross-dipole radiator 110 through an excitation position 116 and an excitation position 117 of the cross-dipole radiator 110, respectively.

[0032] The feed element 130 extends toward the front of the antenna assembly 100 outside the conductive supporting member 120 to the rear side of the cross-dipole radiator 110. The conductive supporting member 120 includes a side wall 121 parallel to the direction 171, that is, a side wall 121 corresponding to a side of its rectangular cross section that is parallel to the direction 171. The feed line 132 is fixed at a specific position outside the conductive supporting member 120 (for example, by a dielectric screw). The conductive supporting member 120 is coupled to the reflector 150 to provide a ground plane for the strip conductor feed line 132, so that the feed line 132 and the side wall 121 form an air microstrip transmission line to transmit a radio frequency (RF) signal. The feed line 133 and the feed line 134 are respectively fixed at specific positions in the rear of the cross-dipole radiator 110. The cross-dipole radiator 110 is coupled to the reflector 150 through the conductive supporting member 120 to provide a ground plane for the strip conductor feed line 133 and the feed line 134, so that the feed line 133 and the feed line 134 respectively form air microstrip transmission lines with the cross-dipole radiator 110 to transmit RF signals on the feed line 133 and the feed line 134.

[0033] The feed element 140 includes a power divider 141, a feed line 142, a feed line 143, and a feed line 144. At least most of the feed element 140 may be mounted forwardly of the reflector 150. In particular, the feed line 142 extends forwardly from the reflector 150 to be coupled to an input end of the power divider 141. The feed line 143 is coupled to a first output end of the power divider 141 and extends from the first output end of the power divider 141 parallel to the main surface of the cross-dipole radiator 110. The feed line 144 is coupled to a second output end of the power divider 141 and extends from the second output end of the power divider 141 parallel to the main surface of the cross-dipole radiator 110. The feed line 143 and the feed line 144 respectively extend symmetrically from the power divider 141. Each feed line includes an inductive element extending from the power divider 141 and a capacitive element extending from the inductive element. The feed line 143 and the feed line 144 extend until they cross the slot 113 and the slot 114 respectively (for example, to make the capacitive element of each feed line to cross the slot), so as to excite the cross-dipole radiator 110 through corresponding excitation positions 118 and 119 of the cross-dipole radiator 110, respectively. [0034] The feed element 140 extends toward the front of the antenna assembly 100 through the hollow column-shaped interior of the conductive supporting member 120 and extends to the front side of the cross-dipole radiator 110 through the opening 115. The conductive supporting member 120 includes a side wall 122 parallel to the direction 172, that is, a side wall 122 corresponding to a side of its rectangular cross section that is parallel to the direction 172. The feed line 142 is fixed at a specific position inside the conductive supporting member 120 (for example, by a dielectric screw). The conductive supporting member 120 is coupled to the reflector 150 to provide a ground plane for the strip conductor feed line 142, so that the feed line 142 and the side wall 122 form an air microstrip transmission line to transmit a radio frequency (RF) signal. The feed line 143 and the feed line 144 are respectively fixed at specific positions in front of the cross-dipole radiator 110 (for example, by fixing members 181 and 182). The cross-dipole radiator 110 is coupled to the reflector 150 through the conductive supporting member 120 to provide a ground plane for the strip conductor feed line 143 and the feed line 144, so that the feed line 143 and the feed line 144 respectively form air microstrip transmission lines with the cross-dipole radiator 110 to transmit RF signals on the feed line 143 and the feed line 144.

[0035] The feed element 130 further includes an input section 135 and a bending section 136 that may be positioned on the rear side of the reflector 150. A first end of the input section

135 is configured to receive downlink RF signals from, for example, a phase shifter 161 that is positioned rearwardly of the reflector 150 and to transmit uplink RF signals to the phase shifter 161. A second end of the input section 135 is coupled to the feed line 132 located in front of the reflector 150 through the bending section 136. The input section 135 and a housing 160 of the phase shifter 161 form a microstrip transmission line (for example, an air microstrip transmission line). The bending section 136 and the reflector 150 may likewise form a microstrip transmission line (for example, an air microstrip transmission line). In the illustrated embodiment (see, e.g., FIG. 2), the phase shifter 161 is a cavity phase shifter, and a strip conductor transmission line in the phase shifter 161 extends parallel to the reflector 150. The main surface of the feed line 132 extends parallel to the direction 171 so as to feed the cross-dipole radiator 110. The main surface of the input section 135 extends parallel to the housing 160 of the phase shifter 161, that is, along the longitudinal axis 170, so as to be connected with the phase shifter 161. The bending section

136 is connected between the second end of the input section 135 and the feed line 132 to adapt an extension direction of the main surface of the feed line 132 to an extension direction of the main surface of the input section 135. The bending section 136 includes a flat portion 1361 extending parallel to the main surface of the reflector 150, a bending portion 1362 which is bent backwards relative to the main surface of the reflector 150 to a plane extending from the main surface of the input section 135, and a bending portion 1363 which is bent forwards relative to the main surface of the reflector 150 to a plane extending from the main surface of the feed line 132. The bending section 136 can be easily formed by a process such as die casting and pultrusion when the feed element 130 is monolithically formed by sheet metal. The first end of the input section 135 is provided with a connection groove 1353 (FIG. 8), and an output portion 1612 of the phase shifter 161 passes through the connection groove 1353 and is soldered to the first end of the input section 135, so that the input section 135 receives an RF signal from the phase shifter 161 and transmits an RF signal to the phase shifter 161.

[0036] The feed element 140 further includes an input section 145 and a bending section 146 that may be positioned on the rear side of the reflector 150. A first end of the input section 145 is configured to receive downlink RF signals from, for example, a phase shifter 162 that is positioned behind the reflector 150 and to transmit uplink RF signals to the phase shifter 162. A second end of the input section 145 is coupled to the feed line 142 located in front of the reflector 150 through the bending section 146. The input section 145 and a housing 160 of the phase shifter 162 form a microstrip transmission line (for example, an air microstrip transmission line). The bending section 146 and the reflector 150 may likewise form a microstrip transmission line (for example, an air microstrip transmission line). In the illustrated embodiment, the phase shifter 162 is a cavity phase shifter, and a strip conductor transmission line in the phase shifter 162 extends parallel to the reflector 150. The main surface of the feed line 142 extends parallel to the direction 172 so as to feed the cross-dipole radiator 110. The main surface of the input section 145 extends parallel to the housing 160 of the phase shifter 162, that is, along the longitudinal axis 170, so as to be connected with the phase shifter 162. The bending section 146 is connected between the second end of the input section 145 and the feed line 142 to adapt an extension direction of the main surface of the feed line 142 to an extension direction of the main surface of the input section 145. The bending section 146 includes a flat portion 1461 extending parallel to the main surface of the reflector 150, a bending portion 1462 which is bent backwards relative to the main surface of the reflector 150 to a plane extending from the main surface of the input section 145, and a bending portion 1463 which is bent forwards relative to the main surface of the reflector 150 to a plane extending from the main surface of the feed line 142. The bending section 146 can be easily formed by a process such as die casting and pultrusion when the feed element 140 is monolithically formed of sheet metal. The first end of the input section 145 is provided with a connection groove 1453, and an output portion 1622 of the phase shifter 162 passes through the connection groove 1453 and is soldered to the first end of the input section 145, so that the input section 145 receives an RF signal from the phase shifter 162 and transmits an RF signal to the phase shifter 162.

[0037] In the illustrated embodiment, the housing 160 of the phase shifter 162 extends along the longitudinal axis 170. It should be understood that in other embodiments, the main surface of the housing 160 of the phase shifter may extend in a plane parallel to the direction 171 or the direction 172, and the main surfaces of the input sections 135 and 145 connected to the output portion of the phase shifter extend parallel to the main surface of the housing 160. In such an embodiment, it is possible that only one of the feed elements 130 and 140 includes a bending section. Taking the case in which the main surface of the housing 160 and the main surfaces of the input sections 135 and 145 extend parallel to the direction 171 as an example, since the main surface of the feed line 132 also extends parallel to the direction 171, the main surface of the input section 135 of the feed element 130 and the main surface of the feed line 132 may be on the same plane. Therefore, the feed element 130 may not include a bending section. The main surface of the feed line 142 extends parallel to the direction 172, and the main surface of the input section 145 of the feed element 140 and the main surface of the feed line 142 are not on the same plane. Therefore, the feed element 140 may include the bending section 146 to adapt the extension direction of the main surface of the feed line 142 to the extension direction of the main surface of the input section 145.

[0038] In the illustrated embodiment, the feed elements 130 and 140 respectively form corresponding air microstrip transmission lines with the housing 160 of the phase shifter, the reflector 150, the conductive supporting member 120, and the cross-dipole radiator 110. It should be understood that in other embodiments, a non-air dielectric microstrip transmission line may be formed.

[0039] Although some specific examples of the present disclosure have been described in detail by examples, those skilled in the art should understand that the above examples are only for illustration, not for limiting the scope of the present disclosure. The examples disclosed herein can be combined arbitrarily without departing from the spirit and scope of the present disclosure. Those skilled in the art should also understand that various modifications can be made to the examples without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the Claims attached.