CN217468809U - Reflector assembly for an active antenna unit, and active antenna unit and base station antenna with a reflector assembly - Google Patents

Abstract

The present disclosure relates to reflector assemblies for active antenna units and base station antennas having reflector assemblies. A reflector assembly is provided that is adaptable for use with an active antenna unit and/or a base station antenna, the reflector assembly including a reflector body and a lip extending around a perimeter of the reflector body, wherein a plurality of fin structures extend around the perimeter of the reflector body. The fin structure may be formed as a channel member, which may be formed from sheet metal, or provided as a separate extruded or die-cast member that may be coupled to the reflector body.

Description

Reflector assembly for an active antenna unit, and active antenna unit and base station antenna with a reflector assembly

Technical Field

The present invention relates generally to radio communications and, more particularly, to base station antennas for cellular communication systems.

Background

Cellular communication systems are well known in the art. In a cellular communication system, a geographic area is divided into a series of areas or "cells" that are served by respective macrocell base stations. Each macrocell base station can include one or more base station antennas configured to provide bidirectional radio frequency ("RF") communications with subscribers within a cell served by the base station. In many cases, each base station is divided into "sectors. In one common configuration, a hexagonal cell is divided into three 120 ° sectors in the azimuth plane, and each sector is served by one or more macrocell base station antennas having an azimuth half-power beam width (HPBW) of approximately 65 °. So-called small cell base stations may be used to provide service in high traffic areas within a portion of the cell. Typically, the base station antenna is mounted on a tower or other elevated structure, with the radiation pattern produced by the base station antenna directed outwardly.

Certain components of the base station antenna may generate heat. For example, the radio may generate heat. In the past, external heat fins have been provided in the housing of the base station antenna and in the body or chassis of the sub-unit/radio unit to help dissipate the generated heat. Further details of example conventional antennas can be found in co-pending WO2019/236203 and WO2020/072880, the contents of which are incorporated herein by reference as if fully set forth herein.

SUMMERY OF THE UTILITY MODEL

According to an embodiment of the present invention, a fin structure coupled to a reflector body is provided which does not require the fin structure to be integrated with the reflector body and/or a reflector main surface.

An embodiment of the utility model relates to a reflector assembly for base station antenna, this reflector assembly includes: a reflector body having an outer periphery providing a lip extending outwardly from the reflector body; and a plurality of fin structures stacked in a front-to-rear direction around the outer periphery.

The reflector body may have a front surface. The lip may extend laterally and/or longitudinally behind the front surface. A plurality of fin structures may be located in front of the lip.

The reflector body may be rectangular with a pair of long sides and a pair of short sides. The lip may be provided as a plurality of outwardly extending lip segments, at least one lip segment extending outwardly from each of the long and short edges.

The lip may be defined by at least one fold or bend in a portion of the sheet metal providing the reflector body.

The lip may have four lip segments. Adjacent end portions of at least first and second of the lip segments may be spaced apart and define an open corner space.

The reflector assembly may further include a coupling member extending across the open corner space.

At least some of the plurality of fin structures may be provided by a stacked set of U-shaped channels oriented such that open end faces of the U-shaped channels face outwardly away from the reflector body and closed ends of the U-shaped channels are adjacent or in close proximity to a side, top or bottom wall of the reflector body.

At least some of the plurality of fin structures may be provided by a stacked set of L-shaped channels oriented such that the short ends of the L-shaped channels are adjacent or in close proximity to a side, top or bottom wall of the reflector body.

The reflector body may have a pair of laterally spaced side walls and longitudinally spaced top and bottom walls surrounding the front surface of the reflector body, and wherein the side, top and bottom walls are perpendicular to and extend rearwardly in a front-to-rear direction between the lip and the front surface of the reflector body.

A first subset of the plurality of fin structures may be secured to the side wall and a second subset of the plurality of fin structures may be secured to the top wall or the bottom wall.

At least some of the plurality of fin structures may be welded, brazed and/or riveted to one or more of the top, bottom or side walls of the reflector body.

The reflector body may have a plurality of apertures, at least some of which have a lateral extension in the range of 20-90% of the lateral extension of the reflector body.

At least some of the plurality of apertures may also have a lateral extension in the range of 10-60% of the longitudinal extension of the reflector body.

The reflector body may be provided as a frame providing a lip. The reflector body may be configured to cooperate with one or more substrates for defining a reflector front surface behind the radiating element and in front of the radio device.

At least some of the plurality of fin structures may be provided by an elongate channel member that is bendable or foldable to define a respective fin structure comprising first and second sections that are coplanar and orthogonal to each other, whereby the bending forms a 90 degree bend joint, and wherein the first and second sections of the elongate channel extend in front of the lip.

The lip may extend laterally outward from and perpendicular to the right and left side walls. The lip may also extend longitudinally from and perpendicular to the top and bottom walls.

At least some of the plurality of fin structures may be provided by an extruded or die cast member as a separate component from the reflector body.

At least some of the plurality of fin structures may have a fin surface with at least one curvilinear, outwardly facing perimeter defining a recess configured to receive a respective securing member.

The reflector body and the plurality of fin structures may have a corrosion resistant surface treatment such as plating and/or coating or electroplating.

Some embodiments relate to an active antenna unit that includes a reflector assembly and a radio behind the reflector assembly, a radio housing holding the radio, and a radiating element in front of the reflector assembly.

Some embodiments relate to base station antennas that include reflector assemblies described herein.

Still other embodiments relate to a reflector assembly for a base station antenna, the reflector assembly comprising: a reflector body having a front face with a perimeter and a heat conducting fin structure comprising a plurality of stacked channel members. The stacked channel members are coupled to the reflector body and extend laterally and/or longitudinally outward from a perimeter of the reflector body.

The reflector assembly may further include a lip extending outwardly from and behind the perimeter of the front face of the reflector body.

The reflector body may have/be formed from sheet metal and the lip may be formed from at least one bend in a portion of the sheet metal.

The stacked channel members may comprise sheet metal U-shaped or L-shaped channels.

The stacked channel members may be provided as extruded or die cast members.

The reflector assembly may further comprise a dielectric liner located between the plurality of stacked channel members and the facing portion of the reflector body.

It should be noted that various aspects of the disclosure described with respect to one embodiment may be included in other different embodiments, even if not specifically described. In other words, features of all embodiments and/or any embodiments may be combined in any manner and/or combination as long as they do not conflict with each other.

Drawings

Fig. 1 is a front, side perspective and partially exploded view of a reflector assembly according to an embodiment of the invention.

Fig. 2 is a front, side perspective and assembly view of the reflector assembly shown in fig. 1.

Fig. 3 is a front, side, and partially exploded view of an active antenna module having the reflector assembly shown in fig. 1 and 2, in accordance with an embodiment of the present invention.

Fig. 4A is a front, side perspective view of another embodiment of a reflector assembly according to an embodiment of the present invention.

Fig. 4B is a partially exploded front perspective view of a portion of an example active antenna unit having the reflector assembly shown in fig. 4A, in accordance with an embodiment of the present invention.

Fig. 4C is a greatly enlarged view of a portion of the reflector assembly and radio shown in fig. 4B.

FIG. 5 is a greatly enlarged front, side perspective view of a corner of the reflector assembly shown in FIG. 2.

Fig. 6A is a front perspective view of another reflector assembly according to an embodiment of the present invention.

Fig. 6B and 6C are side, perspective views of example extruded or die-cast fin members including stacked fin groups according to some embodiments of the present invention.

Fig. 7 is a front, side perspective and partially exploded view of another embodiment of an active antenna element and reflector assembly according to an embodiment of the present invention.

Fig. 8A and 8B are assembly views of reflector assemblies having different metal surfaces according to embodiments of the present invention, wherein fig. 8B illustrates the reflector assembly with a surface treatment, thereby facilitating stability under harsh environmental conditions.

Fig. 9A and 9B are enlarged schematic views of a portion of a plurality of thermal fin and reflector assemblies and a thermally conductive liner according to an embodiment of the invention.

Fig. 9C and 9D are enlarged side perspective views showing corner portions of a reflector body according to alternative embodiments thereof according to embodiments of the present invention.

Fig. 10A-10E are enlarged schematic views of a portion of a reflector assembly and an example configuration of a plurality of thermal fins according to an embodiment of the invention.

Fig. 11A is a schematic diagram of a fin structure that may be bent to form a fin, according to an embodiment of the invention.

Fig. 11B is a schematic diagram of the fin structure shown in fig. 11A in a bent configuration to provide two sides of the fin structure (e.g., side fins and top fins or side fins and bottom fins) in accordance with an embodiment of the present invention.

Fig. 12 is a schematic diagram of a bent fin structure that may be provided by additional bends in a starting fin structure, according to an embodiment of the invention.

Fig. 13A is a top, side perspective view of another example starting fin structure having a plurality of preformed notches for bending in accordance with an embodiment of the present invention.

Fig. 13B is a front, side perspective view of the starting fin structure shown in fig. 13A bent at multiple places to form a frame-shaped fin structure, in accordance with an embodiment of the present invention.

Fig. 13C is a front, side perspective view of the fin structure shown in fig. 13B assembled to a reflector body, in accordance with an embodiment of the present invention.

Fig. 13D is a greatly enlarged view of a corner portion of the assembly shown in fig. 13C.

Fig. 14 is a rear perspective view of a base station antenna including an active antenna element with a reflector assembly that remains at least partially outside of a passive housing according to an embodiment of the present invention.

Fig. 15 is a simplified transverse cross-sectional view of a base station antenna having an active antenna element with a reflector assembly retained within the base station antenna in accordance with an embodiment of the present invention.

Detailed Description

The demand for cellular communication capabilities has grown at a high rate. As a result, the number of base station antennas has proliferated in recent years. Base station antennas are relatively large and heavy and, as mentioned above, are typically mounted on antenna towers. Due to wind loads on the antenna and the weight of the antenna and associated radio, cabling, etc., an antenna tower must be built to support significant loads. This increases the cost of the antenna tower.

In the following description, active antenna elements and their components for a base station antenna are described using terms that assume that the base station antenna is mounted for use on a tower with the longitudinal axis of the antenna extending along a vertical (or near vertical) axis and the front surface of the antenna mounted opposite the tower or other mounting structure so as to be directed toward the coverage area of the antenna.

Embodiments of the present invention will now be discussed in more detail with reference to the accompanying drawings.

Die cast or extruded reflector structures with integrated heat sinks in active antenna elements are described in co-pending PCT/CN2021/116847, the contents of which are incorporated herein by reference as if fully set forth herein. However, integrating the heat sink into the reflector structure may require relatively expensive tooling and/or manufacturing techniques. The present inventive concept provides an alternative reflector assembly configuration that may reduce cost and/or weight of the reflector structure.

Referring to fig. 1, 2 and 5, there is shown a reflector assembly 10 having a reflector body 10b with a lip 15 extending outwardly from the reflector body 10 b. The lip 15 may have a first 15 extending longitudinally from and perpendicular to the top and bottom walls 10t, 10w, 10t and 10w, respectively ₁ And a second 15 ₂ A lip section 15 s. The lip 15 may have a third 15 extending laterally outwardly from the right and left side walls 10s, 10s respectively ₃ And fourth 15 ₄ A lip section 15 s. As shown, the lip 15 is perpendicular to each of the right and left side walls 10s, 10s and the bottom and top walls 10w, 10 t. A plurality of fin structures 25 may be located in front of the lip 15, the plurality of fin structures 25 being thermally conductive heat dissipating fins. The fin structure 25 may be provided with a plurality of fin surfaces 25f, which plurality of fin surfaces 25f may be provided as parallel planar fin surfaces and may be located in front of the lip 15, generally flush with or behind the front surface of the reflector body 10 b.

In some embodiments, there are a plurality of fin surfaces 25f, typically 3-10, more typically 3-6, extending from all four sides (left and right sides and top and bottom sides) of the reflector body 10 b. However, the fin structure 25 may be provided on a subset of the sides, such as two or three sides, rather than all four sides as shown.

The fin surface 25f may extend from the main reflector body 10b a distance equal to, greater than, or less than the distance that the lip 15 extends from the reflector body 10 b. Different fin surfaces 25f may have different extension lengths.

The reflector body 10b may be formed of a sheet metal such as a metal including or defined by aluminum. The lip 15 may be formed by bending a portion of the sheet metal providing the reflector body 10 b. The lips 15 may have open corner spaces 11 between adjacent end portions of adjacent 15n lip segments 15 s.

In some embodiments, at least some of the fin structures 25 may be formed from a metal, such as sheet metal.

The reflector assembly 10 may comprise at least one coupling member 29, the at least one coupling member 29 extending between and above and/or behind the corresponding open corners 11. The coupling member 29 may be square or rectangular, but other shapes may be used. As shown, there are four coupling members 29 at the four corners, and the coupling members 29 can cooperate with the lip 15 to define an enclosed reflector perimeter surface to isolate the radio 50 from the radiating element 40 (fig. 3) and/or to provide a water-resistant or water-proof barrier.

The (main) reflector body 10b may have a rectangular shape in which a pair of long sides and a pair of short sides surround the front surface 10 f. In the working position (fig. 14), the long sides may extend longitudinally and the short sides may extend transversely.

The fin structure 25 may be provided by a mating fin structure attached to at least one of the side wall 10s, the top wall 10t, or the bottom wall 10w of the reflector body 10 b. The fin structure 25 may be a metal stamped or other metal shaped and formed member, and may be a separate component from the reflector body 10 b. The fin structure 25 need not be a die cast or extruded fin, but may be so configured (fig. 6A-6C).

The fin structure 25 may be attached to the reflector body 10b using any suitable attachment configuration, such as rivets, welding, solder joints, brazing, chemical bonding, and the like. For welds or welds, one or more spaced apart welds or weld joints may be provided along the outwardly facing surface of each facing fin structure 25 and one or both of each end wall 10t, 10w or each side wall. For staking, a TOX staking process may be used to facilitate a suitable sealing configuration. The TOX riveting process is a cold joining process, also known as "TOX-rivet", in which the sheet metals to be joined are force-joined and positively locked to each other in a continuous forming process during the riveting or crimping process.

In some embodiments, a subset of the fin structures 25 may be attached together and to the lip 15 without the need to be welded, or riveted to the side wall 10s, top wall 10t, or bottom wall 10 w. For example, the mating components may be secured together using a suitable arrangement and/or frictional engagement or the like. In still other embodiments, the fin structure 25 may be attached to the reflector body in other ways, and a reflector body without the lip 25 may be provided.

Referring to fig. 1, 2, 5 and 10A, for example, at least some of the plurality of fin structures 25 pass through a group 25 of stacked U-shaped channels 25U ₁ 、25 ₂ Provision is made for the orientation to be such that the open end 25e of the U-shaped channel 25U faces outwardly away from the reflector body 10b and the closed end 25c of the U-shaped channel 25U is adjacent or in close proximity to the side wall 10s, top wall 10t or bottom wall 10w of the reflector body 10 b. It will be understood that the term "U-shaped" is used broadly herein and encompasses, for example, channels in which the side walls and base wall meet at a sharp angle (e.g. a 90 ° angle), as opposed to a rounded joint, and encompasses structures in which the side walls do not extend outwardly the same length.

As shown in fig. 10B-10E, at least some of the plurality of fin structures 25 are provided by a set of stacked L-shaped channels 25L, oriented such that the short ends 25s of the L-shaped channels are adjacent or in close proximity to the side walls 10s, top wall 10t or bottom wall 10w of the reflector body 10B, and the long ends of the L-shaped channels extend outwardly from the short ends.

Referring to fig. 3, the reflector assembly 10 may be provided in the active antenna unit 110. The active antenna unit 110 may include a radome 30 and a radiation element 40 protruding to the front of the feed plate 40 f. The reflector assembly 10 is located behind the radiating element 40 and in front of a radio housing 50h containing the radio 50.

In some embodiments, radiating elements 40 may be configured as massive multiple input multiple output (mMIMO) arrays that may operate in the 3-4GHz frequency range. The radio housing 50h may include heat/thermal fins 50f extending rearwardly.

It is noted that the term "active antenna unit" is interchangeably referred to herein as an "active antenna module". The active antenna module may be deployed as a stand-alone base station antenna, or may be deployed in a base station antenna configured as a larger antenna structure that includes additional active antenna modules and/or a conventional "passive" antenna array that may be connected to radios external to the antenna structure.

Referring to fig. 4A-4C, at least some of the fin structures 25 of the reflector assembly 10 may have recesses 12. The recess 12 may have a curved line, for example a semi-circle or an arc. Other recess shapes may be used. The recesses 12 may be provided as a fan-cut pattern over the length of the respective surface 25f of the fin structure 25. The recess 12 may be configured to receive a securing member 115 (e.g., a screw) to couple the reflector assembly 10 to the radio housing 50 h. The radio housing 50h may include a mating aperture 50a that receives the securing member 115.

Referring to fig. 6A-6C, at least some of the fin structures 25 may be provided as stacked planar fin surfaces 25f provided by a die cast or extruded body 125. The die cast or extruded body 125 may include an inner wall 125w, which inner wall 125w may be coupled to the reflector body 10b, e.g., to one of the side wall 10s, the top wall 10t, or the bottom wall 10 w. In some embodiments, the rear wall 125b may be coupled to the lip 15 and/or positioned against the lip. In some embodiments, the inner wall 125w and the back wall 125b can be coupled to respective adjacent surfaces (e.g., the side wall 10s and the lip 15) of the reflector body 10 b. Fig. 6B and 6C illustrate die cast or extruded bodies 125 that may be provided in different lengths, e.g., a short side length 125s and a long side length 125l for the short side and the long side of the reflector body 10B, respectively.

As shown in fig. 7, the reflector body 10b may have a frame configuration, whereby the front surface 10f has a front perimeter with cut-outs and/or apertures 28, which apertures 28 extend between the side walls 10s and have a lateral extension La in the range of 20-99% of the lateral extension La of the reflector body 10 b. At least some of the plurality of apertures 28 may also have a longitudinal extension Lo in the range of 10-90% of the longitudinal extension Lo of the reflector body 10 b.

One or more bridges 128 may provide at least a portion of the front surface 10f and may extend between adjacent/neighboring apertures 28.

The aperture 28 may be located in front of the one or more cavity filters 60 and behind the feed plate 40f with the radiating element 40. The front surface 10f may surround the periphery of the feed plate 40f, and the cavity filter 60 may have a front surface that cooperates with the reflector body 10b to provide a reflective surface to provide a reflector function. The cavity filter 60 may be a resonant cavity filter as is well known to those skilled in the art. The radio may have a metal cover 50 c.

The cavity filter 60 may cooperate with the radio cover 50c and thus the reflector body 10b for defining a reflector for the radiating element 40 eliminates the need for a separate reflector behind the feed plate 40f and in front of the cavity filter 60 in conventional active antenna units.

Referring to fig. 8A and 8B, the reflector assembly 10 may have a surface treatment 75 whereby the surfaces of the fin structure 25 and the reflector body 10B are fabricated to improve preservation in harsh environments such as salt, fog, smoke, and other environmental exposures prior to assembly of the radiating element 40. The surface treatment may include plating, coating and/or electroplating of the metal(s) to provide a corrosion resistant surface.

Fig. 9A illustrates that the reflector assembly 10 may include a rivet 200, the rivet 200 extending through the walls 10t, 10w, 10s of the reflector body 10b and into the wall provided by the closed end 25e of the U-shaped channel 25U. The rivet 200 may also extend through a dielectric liner 210 located between the reflector body 10 and the U-shaped channel 25U. In some embodiments, the dielectric liner 210 may be formed of a thermally conductive material. Fig. 9B illustrates the dielectric liner 210 on the inner surface of the walls 10t, 10w, 10 s. Where used, the internal and external pads 210 may also be used together in some embodiments (not shown).

The dielectric liner 210 may reduce the risk that the interface between the walls 10t, 10w, 10s and the corresponding fin structures 25, 25', 125 (shown by way of example with U-shaped channels 25U) may act as a source of passive intermodulation distortion.

FIG. 9A also illustrates the use of three fin structures 25 ₁ 、25 ₂ 、25 ₃ Thereby providing 6 fin surfaces 25f defined by three stacked U-shaped channels 25U.

Fig. 9C illustrates that the lip 15 may have a forward facing end 15e, which forward facing end 15e projects forward of the major surface 15p of the lip 15. In some embodiments, a portion of the sheet metal may be bent twice to provide the lip 15 and the forward facing end 15 e. The set of fin structures may be slidably received by the lip 15 within the reflector body 10b and the forward facing end 15e, thereby facilitating ease of assembly/alignment.

In some embodiments, as shown in fig. 9D, the forward facing end 15e may itself be curved inwardly to provide a clamping surface to the fin structure.

Fig. 10A-10D show examples of reflector assemblies 10 having different arrangements and configurations of fin structures 25, 25'. Fig. 10B-10D show a fin structure 25' having L-shaped channels 25L, with the short end 25s abutting the reflector body 10B, or being located in close proximity to the reflector body 10B (e.g., wall 10s, 10t, or 10 w).

The term "close proximity" refers to a location 0-1mm from an adjacent wall, such as the bottom wall 10w, top wall 10t, or side wall 10s, to facilitate conductive heat transfer. If the dielectric liner is located between the components such that the fin structure 25, 25', 125 and reflector body 10b abut the dielectric liner, this distance can vary and the size of the close proximity increases the width of the dielectric liner.

Fig. 10A and 10D illustrate that different fin surfaces 25f may have different lengths, and some may be longer than the lip 15. Others may be shorter than the lip or have the same length.

FIGS. 10B, 10C and 10D illustrate the short of the wall 10s, 10t or 10w of the L-shaped channel 25L facing the reflector body 10BThe different directions of the sides 25 s. FIG. 10D illustrates four L-shaped channels 25L, 25 ₁ '、25 ₂ '、25 ₃ '、25 ₄ '. Fig. 10C illustrates three fin surfaces 25f, while fig. 10D illustrates four fin surfaces 25 f.

Fig. 10E illustrates that the fin structure 25 may be provided with an L-shaped channel 25L having an extra-long 25xl short side 25s, which extra-long 25xl short side 25s may be coupled to one or more other short sides 25s of other channel members, such as the L-shaped channel member 25L (or even a U-shaped channel member). Thus, the fin structure 25 may provide a nested configuration of L-shaped channels 25L, where one "L" has an extra long 25xl short side into which the other short side 25s is embedded and may be attached. This configuration may allow the fin structure 25 to be pre-assembled together and then attached as a unit to the reflector body 10 b.

Turning now to fig. 11A-11B, the fin structure may be provided by bending the channel structure at least once. Fig. 11A illustrates a starting fin structure 25 having at least one notch 26 defining a bend region 25 b. Fig. 11B illustrates the resulting fin structure whereby the first and second fin structure sections of the fin structure for the reflector assembly 10 are coplanar or parallel to each other and oriented at 90 degrees to each other and can be coupled to both sides of the reflector body 10B.

Fig. 12 illustrates a three-sided fin structure having two curved sections 25b that form first and second fin sides that are coplanar and first and second sections that are 90 degrees from each other, whereby the respective curves can define a 90 degree bend joint for adjacent curved sections (which would include two notches 26 in the starting fin structure of fig. 11A).

Referring to fig. 13A-13D, the starting fin structure may be configured to form a four-sided "frame" shaped fin structure having three curved sections (which would include three notches 26 in the starting fin structure). The notches 26 may be preformed or may be manufactured continuously as each continuation bend 25b is manufactured, or may be manufactured in a starting piece defining spaced apart locations. The notched section 26 may form a bridge 126 that connects and extends between the bent edges of the folded/bent fin structure. After the frame fin structure is formed, a corner 129 may be formed by the free ends of the abutting or closely spaced channel members.

The use of a multi-sided folded/curved fin channel structure, particularly a two-, three-, or four-sided curved channel fin structure, can provide increased stiffness to the reflector body 10b over a single-sided fin structure and allow for the use of a thinner reflector body 10 b.

In some embodiments, the active antenna unit 110 with the radio 50 may be configured as a 5G module. With the introduction of fifth generation ("5G") cellular technology, conventionally deployed base station antennas now have active beamforming capabilities. Active beamforming refers to the transmission of RF signals through a multi-column array of radiating elements, wherein the relative amplitudes and phases of the sub-components of the RF signals transmitted (or received) by different radiating elements of the array are adjusted such that the radiation patterns formed by the individual radiating elements beneficially combine in one or more desired directions to form a narrower antenna beam with higher gain. Using active beamforming, the shape and pointing direction of the antenna beams produced by a multi-column array may be varied, for example, on a time slot-by-time slot basis of a time division duplex ("TDD") multiple access scheme. Furthermore, in a multi-user MIMO scenario, different antenna beams may be generated simultaneously on the same frequency resource. More complex active beamforming schemes may apply different beams to different physical resource blocks, which are a combination of frequency resources and time resources by applying beam vectors in the digital domain. Base station antennas with active beamforming capability are often referred to as active antennas. When a multi-column array includes a large number of columns of radiating elements (e.g., sixteen or more), the array is often referred to as a massive MIMO array. A module comprising a multi-column array of radiating elements implementing an active antenna and associated RF circuitry (and possibly baseband circuitry) is referred to herein as an active antenna module.

Referring to fig. 14, a base station antenna 100 is shown in accordance with some embodiments. The base station antenna 100 includes a passive antenna assembly 190 having a plurality of inner linear arrays 111 of radiating elements arranged in a plurality of laterally spaced and adjacent longitudinally extending columns between the top 100t and bottom 100b of the base station antenna 100. In the exemplary embodiment, there are eight columns of the linear array 111 of radiating elements.

An active antenna element 110 may be held against the rear portion 100r of the housing 100h of the base station antenna 100 including the passive antenna component, the active antenna element 110 having a bracket assembly 112 with first and second laterally extending spaced brackets 113, 114 of the bracket assembly 112. The housing 100h has a front surface 100f and sides 100s and a back 100r that define a radome. The bracket assembly 112 may also mount the base station antenna housing 100h with the active antenna element 110 to a target structure such as a mast 10.

Fig. 15 illustrates another embodiment of a base station antenna 100 having a housing 100h, the base station antenna 100 including a passive antenna assembly 190 sized and configured to hold an active antenna element 110 within at least a portion thereof. In some embodiments, the reflector assembly 10 may be at least partially retained within the base station antenna housing 100h without requiring any or all of the components of the active antenna element 110.

The base station antenna 100 may include one or more arrays of low band radiating elements, one or more arrays of mid band radiating elements, and one or more arrays of high band radiating elements. The radiating elements may each be a dual polarized radiating element. Further details of the radiating element may be found in co-pending WO2019/236203 and WO2020/072880, the contents of which are incorporated herein by reference as if fully set forth herein. For further details regarding base station antenna housings having passive antenna components and exemplary active antenna modules, see co-pending U.S. patent application serial No. 17/209,562 and corresponding PCT patent application serial No. PCT/US2021/023617, the contents of which are incorporated herein by reference as if fully set forth herein.

The linear array 111 (of active antenna elements 110) and/or the passive antenna assembly 190 may be provided as a low-band radiating element, a mid-band radiating element, or a high-band radiating element. The high-band radiating elements may be configured to transmit and receive signals in the 3.3-4.2GHz band or portion thereof and/or signals in the 5.1-5.8GHz band or portion thereof. The mid-band radiating elements may be configured to transmit and receive signals in, for example, the 1.427-2.690GHz band or a portion thereof. The low-band radiating elements may be configured to transmit and receive signals in, for example, the 0.616-0.960GHz band or portion thereof.

It will be appreciated that other types of radiating elements may be used, more or fewer linear arrays may be included in the antenna, the number of radiating elements per array may vary, and planar arrays or staggered linear arrays may be used instead of the "straight" linear arrays shown in the figures in other embodiments.

Embodiments of the present invention have been described above with reference to the accompanying drawings, in which embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

In the above discussion, reference is made to a linear array of radiating elements typically included in a base station antenna. It will be understood that the term "linear array" is used broadly herein to encompass both arrays of radiating elements including a single column of radiating elements configured to transmit a sub-component of an RF signal and a two-dimensional array (e.g., a plurality of linear arrays) of radiating elements configured to transmit a sub-component of an RF signal. It will also be appreciated that in some cases the radiating elements may not be arranged along a single line. For example, in some cases, the linear array of radiating elements may include one or more radiating elements that are offset from a line along which the remaining radiating elements are aligned. Such "staggering" of the radiating elements can be done to design an array with a desired azimuth beamwidth. Such a staggered array of radiating elements is configured to transmit a sub-component of the RF signal encompassed by the term "linear array" as used herein.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It will be understood that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. It will also be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a similar manner (i.e., "between" and "directly between," "adjacent" and "directly adjacent," etc.).

The term "about" with respect to a number means that the stated number can vary by +/-20%.

As shown in the figures, relative terms, such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical," may be used herein to describe one element, layer or region's relationship to another element, layer or region. It will be understood that these terms are also intended to encompass different orientations of the device in addition to the orientation depicted in the figures.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used herein, specify the presence of stated features, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, operations, elements, components, and/or groups thereof.

The aspects and elements of all embodiments disclosed above may be combined in any manner and/or with aspects or elements of other embodiments to provide multiple additional embodiments.

Claims (27)

1. A reflector assembly for a base station antenna, the reflector assembly comprising:

a reflector body having an outer periphery providing a lip extending outwardly from the reflector body; and

a plurality of fin structures stacked in a front-to-back direction around the outer periphery.

2. The reflector assembly of claim 1, wherein the reflector body comprises a front surface, wherein the lip extends laterally and/or longitudinally behind the front surface, and wherein the plurality of fin structures are located forward of the lip.

3. The reflector assembly of claim 1 wherein the reflector body is rectangular having a pair of long sides and a pair of short sides, and wherein the lip is provided as a plurality of lip segments extending outwardly, at least one lip segment extending outwardly from each of the long sides and/or each of the short sides.

4. The reflector assembly of claim 1 wherein the lip is defined by at least one of folding or bending a portion of a metal sheet providing the reflector body.

5. The reflector assembly of claim 4 wherein the lip comprises four lip segments, wherein adjacent end portions of at least a first and a second of the lip segments are spaced apart and define an open corner space.

6. The reflector assembly of claim 5 further comprising a coupling member extending across the open corner space.

7. The reflector assembly of claim 1 wherein at least some of the plurality of fin structures are provided by a stacked set of U-shaped channels, oriented such that open end faces of the U-shaped channels face outwardly away from the reflector body and closed ends of the U-shaped channels are adjacent or in close proximity to a side, top or bottom wall of the reflector body.

8. The reflector assembly of claim 1 wherein at least some of the plurality of fin structures are provided by a stacked set of L-shaped channels oriented such that short ends of the L-shaped channels are adjacent or in close proximity to a side, top or bottom wall of the reflector body.

9. The reflector assembly of claim 1 wherein the reflector body has a pair of laterally spaced side walls and longitudinally spaced top and bottom walls surrounding a front surface of the reflector body, and wherein the side, top and bottom walls are perpendicular to and extend rearwardly in a front-to-rear direction between the lip and the front surface of the reflector body.

10. The reflector assembly of claim 9, wherein a first subset of the plurality of fin structures are secured to a side wall, and wherein a second subset of the plurality of fin structures are secured to a top wall or a bottom wall.

11. The reflector assembly of claim 1, wherein at least some of the plurality of fin structures are welded, brazed and/or riveted to one or more of the top, bottom or side walls of the reflector body, optionally with a dielectric liner between the respective fin structure and the corresponding top, bottom or side wall.

12. The reflector assembly of claim 1, wherein the reflector body comprises a plurality of apertures, at least some of the plurality of apertures having a lateral extension in the range of 20-90% of the lateral extension of the reflector body.

13. The reflector assembly of claim 12 wherein at least some of the plurality of apertures further have a longitudinal extension in the range of 10-60% of the longitudinal extension of the reflector body.

14. The reflector assembly of claim 1, wherein the reflector body is provided as a frame providing a lip, wherein the reflector body is configured to cooperate with one or more substrates for defining a front surface of the reflector behind the radiating element and in front of the radio.

15. The reflector assembly of claim 1 wherein at least some of the plurality of fin structures are provided by an elongated channel member that is bendable or foldable to define a respective fin structure comprising first and second sections that are coplanar and orthogonal to each other, whereby the bending forms a 90 degree bend joint, and wherein the first and second sections of the elongated channel extend in front of the lip.

16. The reflector assembly of claim 1 wherein the lip extends laterally outward from and perpendicular to the right and left side walls, and wherein the lip extends longitudinally from and perpendicular to the top and bottom walls.

17. The reflector assembly of claim 16 wherein at least some of the plurality of fin structures are provided by an extruded or die cast member that is a separate component from the reflector body.

18. The reflector assembly of claim 1, wherein at least some of the plurality of fin structures include a fin surface having at least one curvilinear outwardly facing perimeter defining a recess configured to receive a respective securing member.

19. A reflector assembly as claimed in claim 1, wherein said reflector body and said plurality of fin structures include a corrosion resistant surface treatment such as plating and/or coating or electroplating.

20. An active antenna unit, comprising:

the reflector assembly of any one of claims 1-19;

a radio behind the reflector assembly;

a radio housing holding the radio; and

a radiating element in front of the reflector assembly.

21. A base station antenna, characterized in that it comprises a reflector assembly according to any of claims 1-19.

22. A reflector assembly for a base station antenna, the reflector assembly comprising:

a reflector body including a front face having a perimeter; and

a heat conducting fin structure comprising a plurality of stacked channel members coupled to the reflector body and extending laterally and/or longitudinally outward from a perimeter of the reflector body.

23. The reflector assembly of claim 22 wherein the reflector assembly further comprises a lip extending outwardly from and behind a perimeter of the front face of the reflector body.

24. The reflector assembly of claim 23 wherein the reflector body comprises sheet metal, and wherein the lip is formed by bending at least one of a portion of the sheet metal.

25. The reflector assembly of claim 22 wherein said stacked channel member is a sheet metal U-shaped or L-shaped channel.

26. The reflector assembly of claim 22 wherein said stacked channel member is provided as an extruded or die cast member.

27. The reflector assembly of claim 22, further comprising a dielectric liner between the plurality of stacked channel members and the facing portion of the reflector body.

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