Base station antenna

Abstract

An assembly for a radio frequency antenna includes: a cavity housing having a ceiling, a first side wall, and a dividing panel, wherein the ceiling, the dividing panel and the first side wall define a first cavity; a first phase shifter printed circuit board (PCB) mounted in the first cavity; a first input trace holders mounted to the cavity housing outside the first cavity; a first input trace mounted in the first input trace holder, the first input trace electrically connected with the first phase shifter PCB via a first finger extending through the first side wall and engaging the first phase shifter PCB; and a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing and electrically connected with the first phase shifter PCB and with the cavity housing.

Description

Attorney Docket No.9833.7336.WO BASE STATION ANTENNA Related Application

[0001] The present application claims priority from and the benefit of U.S. Provisional Patent Application No.63 / 675,359, filed July 25, 2024, the disclosure of which is hereby incorporated herein by reference in full. Field of the Invention

[0002] The present invention relates generally to telecommunication antennas, and more specifically to radio frequency base station antennas. Background of the Invention

[0003] Cellular communications systems are well known in the art. In a cellular communications system, a geographic area is divided into a series of regions that are referred to as "cells" which are served by respective base stations. Each base station may include one or more base station antennas that are configured to provide two-way radio frequency ("RF") communications with mobile subscribers that are within the cell served by the base station. Typically, the base station antennas are mounted on a tower or other raised structure, with the radiation patterns (also referred to herein as "antenna beams") that are generated by the base station antennas directed outwardly.Attorney Docket No.9833.7336.WO

[0004] A common base station configuration is the three-sector configuration in which a cell is divided into three 120º "sectors" in the azimuth (horizontal) plane. A separate base station antenna provides coverage (service) to each sector. Typically, each base station antenna will include multiple vertically-extending columns of radiating elements that operate, for example, using second generation ("2G"), third generation ("3G") or fourth generation ("4G") cellular network protocols. These vertically-extending columns of radiating elements are typically referred to as "linear arrays," and may be straight columns of radiating elements or columns in which some of the radiating elements are staggered horizontally to narrow the beamwidths of the generated antenna beams in the azimuth (horizontal) plane. Most modern base station antennas include both "low-band" linear arrays of radiating elements that support service in some or all of the 617-960 MHz frequency band and "mid-band" linear arrays of radiating elements that support service in some or all of the 1427-2690 MHz frequency band. These linear arrays are typically formed using dual-polarized radiating elements, which allows each linear array to be connected to a pair of radios (or radio ports of a single radio) so that the linear array can transmit and receive RF signals at two orthogonal polarizations (i.e., an antenna beam is generated at each orthogonal polarization).

[0005] Each of the above-described linear arrays of dual-polarized radiating elements is coupled to two ports of a radio (one port for each polarization). An RF signal that is to be transmitted by the linear array is passed from the radio to the antenna where it is divided into a plurality of sub-components, with each sub- component fed to a respective subset of the radiating elements in the linear array (typically each sub-component is fed to between one and three radiating elements). The sub-components of the RF signal are transmitted through the radiating elements to generate an antenna beam that covers a generally fixed coverage area,Attorney Docket No.9833.7336.WO such as a 120⁰ sector of a cell. Typically these linear arrays will have remote electronic tilt ("RET") capabilities which allow a cellular operator to change, from a control center, the pointing angle of the generated antenna beams in the elevation (vertical) plane in order to change the size of the sector served by the linear array (since the more that the antenna beam is downtilted in the elevation plane, the less the area that is illuminated by the antenna beam, and hence the smaller the size of the area covered by the antenna beam). Since the antenna beams generated by the above-described 2G / 3G / 4G linear arrays are static antenna beams that only change in shape due to adjustments in the downtilt angle of the antenna beam, they are often referred to as "passive" linear arrays.

[0006] Cellular operators are currently upgrading their networks to support fifth generation ("5G") cellular service. One important component of 5G cellular service is the use of multi-column "active" beamforming arrays that operate in conjunction with beamforming radios. The beamforming radios change the amplitudes and / or phases of the sub-components of a signal that is to be transmitted. The sub-components of the signal are passed to respective subsets of the radiating elements of the active beamforming array in order to dynamically adjust the size, shape and pointing direction of the antenna beams that are generated by the active beamforming array. These active beamforming arrays are typically formed using "high-band" radiating elements that operate in higher frequency bands, such as some or all of the 3.3-4.2 GHz and / or the 5.1-5.8 GHz frequency bands, although active beamforming radios may also be provided that operate in other frequency bands such as the upper portion (e.g., 2.5-2.7 GHz) of the mid-band frequency range. The radiating elements in each vertically-extending column of such an active beamforming array are typically coupled to a respective port of a beamforming radio so that each column of radiating elements is fed aAttorney Docket No.9833.7336.WO different sub-component of the signal to be transmitted. The beamforming radio may be a separate device, or may be integrated with the active antenna array. As discussed above, the beamforming radio may adjust the amplitudes and phases of the sub-components of an RF signal that are fed to each port of the radio (and hence to each respective column of radiating elements in the multi-column beamforming array) in order to generate antenna beams that have narrowed beamwidths in the azimuth plane (and hence higher antenna gain). These narrowed antenna beams can be electronically steered throughout the sector by proper selection of the amplitudes and phases of the sub-components of the RF signal. In order to avoid having to increase the number of antennas at cell sites, 5G antennas that include such beamforming arrays also often include passive linear arrays that support legacy 2G, 3G and / or 4G cellular services.

[0007] FIGS.32A and 32B illustrate a conventional base station antenna 100 that includes both passive low-band and mid-band linear arrays and a high-band active beamforming array. In particular, FIG.32A is a front perspective view of the base station antenna 100, and FIG.32B is a schematic front view of the base station antenna 100 with the radome thereof removed. In FIGS.32A and 32B, the axes illustrate the vertical (V), horizontal (H) and forward (F) directions of the base station antenna system 100. In the description that follows, each antenna will be described using terms that assume that the antenna is mounted for use on a tower with the longitudinal axis L of the antenna extending along a vertical axis and the front surface of the antenna mounted opposite the tower pointing toward the coverage area for the antenna.

[0008] Referring to FIG.32A, the base station antenna 170 has a tubular shape with a generally rectangular cross-section. The base station antenna 170 includes a radome 172 a top end cap 174 and a bottom end cap 176. One or moreAttorney Docket No.9833.7336.WO mounting brackets (not shown) may be provided on the rear side of the antenna 170 which may be used to mount the antenna 170 onto an antenna mount (not shown) on, for example, an antenna tower. A plurality of RF ports 178 in the form of RF connectors are mounted in the bottom end cap 176. The RF ports 178 extend through the bottom end cap 176 and are used to electrically connect the base station antenna 170 to external radios (not shown). The radome 172, top end cap 174 and bottom cap 176 may form an external housing for the antenna 170. An antenna assembly (FIG.32B) is contained within the housing.

[0009] FIG.32B is a schematic front view of the antenna assembly that is contained within the housing of base station antenna 170. As shown in FIG.32B, the antenna assembly includes a reflector 150. The reflector 150 may serve as both a structural component for the antenna assembly and as a ground plane and reflector for at least some of the radiating elements (discussed below) of antenna 150. The reflector 150 includes a generally flat metallic surface that extends in the longitudinal direction L of the antenna 170. Various mechanical and electronic components of base station antenna 170 (not shown) are mounted behind the reflector 150.

[0010] The antenna assembly further includes first and second low-band arrays 122-1, 122-2 of low-band radiating elements 124, first and second mid-band arrays 132-1, 132-2 of first mid-band radiating elements 134A, third through sixth mid-band arrays 132-3 through 132-6 of second mid-band radiating elements 134B, and a multi-column high-band array 142 of high-band radiating elements 144. The low-band arrays 122 and mid-band arrays 132 are each implemented as vertically-extending linear arrays of radiating elements. The low-band and mid- band linear arrays 122, 132 may support, for example, 2G, 3G and / or 4G cellular service. Each of the low-band and mid-band linear arrays 122, 132 are passiveAttorney Docket No.9833.7336.WO arrays that generate static antenna beams that provide coverage to a predefined coverage area (e.g., antenna beams that are each configured to cover a 120⁰ sector of a base station), with the only change to the coverage area occurring when the electronic downtilt angles of the generated antenna beams are adjusted (e.g., to change the size of the cell).

[0011] The high-band radiating elements 144 are mounted in four columns in the lower center portion of the reflector 110 to form the multi-column array 142 of high-band radiating elements 144. Each column of the multi-column array 142 may be coupled to a pair of ports (one for each polarization) of a beamforming radio so that the multi-column array 142 operates as an active beamforming array that generates narrowed antenna beams that can be steered in the azimuth plane throughout the coverage area.

[0012] The low-band radiating elements 124 are configured to transmit and receive signals in the 617-960 MHz frequency range or a portion thereof (e.g., the 617-896 MHz frequency band, the 696-960 MHz frequency band, etc.). The first mid-band radiating elements 134A are configured to transmit and receive signals in the 1427-2690 MHz frequency range or a portion thereof (e.g., the 1427-1710 MHz frequency band, the 1427-2200 MHz frequency band, etc.). The second mid- band radiating elements 134B are configured to transmit and receive signals in the 1695-2690 MHz frequency range or a portion thereof (e.g., the 1710-2200 MHz frequency band, the 2300-2690 MHz frequency band, etc.). The second mid-band radiating elements 134B may have a different design than the first mid-band radiating elements 134A. The high-band radiating elements 144 are configured to transmit and receive signals in the 3300-4200 MHz frequency range or a portion thereof. The radiating elements 124, 134A, 134B, 144 are mounted to extend forwardly from the reflector 110.Attorney Docket No.9833.7336.WO

[0013] The low-band and mid-band radiating elements 124, 134A, 134B may each be implemented as dual-polarized radiating elements that each include first and second radiators that are configured to transmit and receive RF energy at orthogonal polarizations. For example, the low-band and mid-band radiating elements 124, 134A, 134B may be implemented as slant -45⁰ / +45⁰ cross-dipole radiating element that include a -45⁰ dipole radiator and a +45⁰ dipole radiator that are arranged to form a cross when the radiating elements 124, 134A, 134B are viewed from the front. The dipole radiators of each low-band and mid-band radiating element 124, 134A, 134B are mounted on a feed stalk (not visible in FIGS.32A and 32B) that passes RF signals between the dipole radiators and an associated feed network.

[0014] While the conventional base station antenna 100 of FIGS.32A-32B can support a wide range of communications services, in practice it can be difficult to manufacture. There is also a push for “green” manufacturing processes for many components, including base station antennas. As such, it may be desirable to provide alternative antenna configurations that can be easily manufactured. Summary of the Invention

[0015] As a first aspect, embodiments of the invention are directed to an assembly for a radio frequency base station antenna comprising: a cavity housing having a ceiling, a first side wall, and a dividing panel, wherein the ceiling, the dividing panel and the first side wall define a first cavity; a first phase shifter printed circuit board (PCB) mounted in the first cavity; a first input trace holders mounted to the cavity housing outside the first cavity; a first input trace mounted in the first input trace holder, the first input trace electrically connected with the first phase shifter PCB via a first finger extending through the first side wall andAttorney Docket No.9833.7336.WO engaging the first phase shifter PCB; and a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing and electrically connected with the first phase shifter PCB and with the cavity housing.

[0016] As a second aspect, embodiments of the invention are directed to an assembly for a radio frequency antenna comprising: a cavity housing having a ceiling, first and second side walls, and a dividing panel between the first and second side wall, wherein the ceiling, the dividing panel and the first side wall define a first cavity, and the ceiling, the dividing panel, the second side wall define a second cavity; first and second phase shifter printed circuit boards (PCBs) mounted in, respectively, the first and second cavities; first and second input trace holders mounted to the cavity housing outside, respectively, the first and second cavities; first and second input traces mounted in, respectively, the first and second input trace holders, each of the first and second input traces electrically connected with, respectively, the first and second phase shifter PCBs via first and second fingers extending through, respectively, the first and second side walls and engaging the first and second phase shifter PCBs; and a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing and electrically connected with the first and second phase shifter PCBs and with the cavity housing.

[0017] As a third aspect, embodiments of the invention are directed to an assembly for a radio frequency antenna comprising: a cavity housing having a ceiling, a first side wall, and a dividing panel, wherein the ceiling, the dividing panel and the first side wall define a first cavity; a first phase shifter printed circuit board (PCB) mounted in the first cavity; a first input trace holder mounted to the cavity housing outside the first cavity; a first input trace mounted in the first input trace holder, the first input trace electrically connected with the first phase shifterAttorney Docket No.9833.7336.WO PCB; and a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing, each of the feed stalks electrically connected with the first phase shifter PCB via a mechanical clip, each of the feed stalks also electrically connected with the cavity housing. Brief Descriptions of the Figures

[0018] FIG. 1 is a perspective view of a portion of a base station antenna according to embodiments of the invention.

[0019] FIG. 2 is an exploded perspective view of the portion of the base station antenna of FIG.1.

[0020] FIG. 3 is a perspective view of a cavity housing for the base station antenna of FIG.1.

[0021] FIG. 4 is an end view of the cavity housing of FIG.3.

[0022] FIG. 5 is an end perspective view of the cavity housing of FIG.3.

[0023] FIG.6 is a perspective view of an input trace holder of the base station antenna of FIG.1.

[0024] FIG.7 is an end view of the input trace holder of FIG.6.

[0025] FIG.8 is a perspective view of an input trace of the base station antenna of FIG.1.

[0026] FIG.9 is a top perspective view of a feed stalk holder of the base station antenna of FIG 1.

[0027] FIG.10 is a bottom perspective view of the feed stalk holder of FIG.9.

[0028] FIG.11 is an alternative bottom perspective view of the feed stalk holder of FIG.9.

[0029] FIG.12 is a perspective view of the feed stalk holder of FIG.9 and a feed stalk.Attorney Docket No.9833.7336.WO

[0030] FIG. 13 is a side section view of the feed stalk holder and feed stalk of FIG.12.

[0031] FIG. 14 is a perspective view of the feed stalk and grounding plate of the base station antenna of FIG.13.

[0032] FIG. 15 is an opposite perspective view of the feed stalk and grounding plate of FIG.14.

[0033] FIG. 16 is a bottom perspective view of the feed stalk and grounding plate of FIG.14.

[0034] FIG.17 is a perspective view of a clip employed to attach the feed stalk of FIG.14 to a phase shifter PCB.

[0035] FIG.18 is an end perspective view of the base station antenna of FIG. 1 without the reflector.

[0036] FIG.19 an end view of the base station antenna as in FIG.18.

[0037] FIG.20 is a perspective view of a feed stalk and feed stalk holder mounted on the cavity housing as in FIG.18.

[0038] FIG.21 is a top, end perspective view of the base station antenna of FIG.1 showing the finger of the input trace contacting the phase shifter PCB.

[0039] FIG.22 is a greatly enlarged perspective view of portions of a feed stalk, a feed stalk holder, and a clip of FIG.17 used to attach the feed stalk to the phase shifter PCB, with the feed stalk holder shown as transparent.

[0040] FIG.23 is an end view of the base station antenna of FIG.1.

[0041] FIG.24 is an end perspective view of the base station antenna of FIG. 1 with the input trace and input trace holder exploded from the remainder of the assembly.

[0042] FIG.25 is a partial end perspective view of the base station antenna of FIG.1 showing the attachment of an input cable to the input trace.Attorney Docket No.9833.7336.WO

[0043] FIGS. 26 and 27 are exploded and assembled views of four sets of feed stalks and cavity housings and a reflector of the base station antenna of FIG.1.

[0044] FIG. 28 is an end perspective view of the base station antenna of FIG. 25 with a calibration PCB in place at one end.

[0045] FIG. 29 is an end view of the base station antenna of FIG.28.

[0046] FIGS. 30A and 30B are perspective views illustrating assembly steps for an input trace according to alternative embodiments of the invention. FIG.30C is an end view of one assembled side of the cavity housing.

[0047] FIGS.31A and 31B are perspective views illustrating assembly steps for an input trace according to further alternative embodiments of the invention. FIG.31C is an end view of one assembled side of the cavity housing.

[0048] FIG.32A is a front perspective view of a conventional base station antenna that includes both passive 2G / 3G / 4G linear arrays and an active beamforming array.

[0049] FIG.32B is a schematic front view of the conventional base station antenna of FIG.32A with the radome removed. Detailed Description of the Invention

[0050] The present invention now is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This 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.

[0051] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of theAttorney Docket No.9833.7336.WO invention are shown. Like numbers refer to like elements throughout and different embodiments of like elements can be designated using a different number of superscript indicator apostrophes (e.g., 10', 10'', 10''').

[0052] In the figures, certain layers, components or features may be exaggerated for clarity, and broken lines illustrate optional features or operations unless specified otherwise. This 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.

[0053] It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention. The sequence of operations (or steps) is not limited to the order presented in the claims or figures unless specifically indicated otherwise.

[0054] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized orAttorney Docket No.9833.7336.WO overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and / or clarity.

[0055] 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 in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0056] As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean "between about X and about Y." As used herein, phrases such as "from about X to Y" mean "from about X to about Y."

[0057] It is noted that aspects of the invention described with respect to one embodiment, may be incorporated in a different embodiment although not specifically described relative thereto. That is, all embodiments and / or features of any embodiment can be combined in any way and / or combination. Applicant reserves the right to change any originally filed claim and / or file any new claim, accordingly, including the right to be able to amend any originally filed claim to depend from and / or incorporate any feature of any other claim or claims although not originally claimed in that manner. These and other objects and / or aspects of the present invention are explained in detail in the specification set forth below. Further features, advantages and details of the present invention will be appreciated by thoseAttorney Docket No.9833.7336.WO of ordinary skill in the art from a reading of the figures and the detailed description of the preferred embodiments that follow, such description being merely illustrative of the present invention.

[0058] Referring now to the drawings, schematic illustrations of a portion of a linear array of a base station antenna, designated broadly at 20, are shown in FIGS. 1 and 2. The portion of the liner array 20 illustrated in FIGS. 1 and 2 includes a cavity housing 22 that includes two cavities 24, two input trace holders 26 that hold input traces 27, two phase shifter printed circuit boards (PCBs) 28, and a plurality of feed stalks 30 (each of which is connected to and part of a respective radiating element such as those discussed above). FIGS.26 and 27 illustrate that the antenna 170 may include four of the linear arrays 20, wherein each linear array 20 has a cavity housing 22 with feed stalks 30 mounted thereon, all of which are mounted on the reflector 150 and aligned in columns along the length of the antenna 170. These components are discussed in more detail below. It will be appreciated that FIGS.26 and 27 only show a sub-assembly of the antenna 170.

[0059] As seen in FIGS.3-5, the cavity housing 22 is a single elongated piece of metal (typically aluminum) of essentially constant cross-section. The cavity housing 22 includes an inner wall 40, two outer walls 42, a floor 44 that underlies the inner and outer walls 40, 42, and a ceiling 46 that overlies the inner and outer walls 40, 42. Two cavities 24 are formed: one each by the inner wall 40, one of the outer walls 42, the floor 44 and the ceiling 46. The floor 44 includes two recesses 48 (one in each cavity 24), and the ceiling includes two recesses 49. Straight flanges 50 extend laterally from each side edge of the ceiling 46. L-shaped flanges 52 extend laterally, then downwardly, from upper portions of the outer walls 42. Recesses 51 are present on the lower portion of the inner surface of each of the L-shaped flanges for mounting of the input trace holders 26.Attorney Docket No.9833.7336.WO

[0060] The cavity housing 22 includes multiple slots and openings along its length to allow components housed in one of the cavities 24 to be connected with components positioned outside of the cavities 24. There are a number of transverse slots 53 present in the ceiling 46 for the mounting of the feed stalks 30 (the slots 53 are best seen in exploded view of FIGS.3 and 5). Also, vertical slots 54 are present in each of the outer walls 42 to allow input traces 27 mounted in the input trace holders 26 to connect with the phase shifter PCBs 28 that are mounted in the cavities 24.

[0061] Referring back to FIGS.1 and 2, the phase shifter PCBs 28 are elongate PCBs with circuitry mounted thereon to induce phase shifting of the RF signals. Such circuitry is well-known and need not be described in detail herein. U.S. Patent No.11,677,141 discloses a variety of cavity phase shifter assemblies and discusses the operation thereof. The entire content of U.S. Patent No. 11,677,141 is hereby incorporated herein by reference.

[0062] As can be seen in FIGS.18 and 19, each of the phase shifter PCBs 28 is positioned within a respective cavity 24. A lower edge of each phase shifter PCB 28 is nested within one of the recesses 48 in the floor 46. The upper edge of each phase shifter PCB 28 is maintained in position by the recesses 49.

[0063] Referring now to FIGS. 6 and 7, each input trace holder 26 is an elongate piece, typically formed of a polymeric material, that has an essentially constant cross-section. As shown in FIGS.6 and 7, the input trace holder 26 has a vertical main body 60, upper and lower inner arms 62, 64 that extend inwardly from the main body 60, and upper and lower outer arms 66, 68 that extend outwardly from the main body 60. Short nubs 70, 72 extend upwardly from the ends of the upper inner and outer arms 62, 66. A ridge 74 extends downwardly from the inner upper arm 62, and a ridge 75 extends upwardly from the inner lower arm 64. Flanges 74,Attorney Docket No.9833.7336.WO 76 extend downwardly from the ends of the lower inner and outer arms 64, 68. A nub 78 extends outwardly from the ends of the flange 76.

[0064] As shown in FIGS. 18, 19, 21 and 22, each input trace holder 26 is positioned within a respective L-shaped flange 52. The nub 78 is received in the recess 51. The flange 74 and the nub 70 abut the outer wall 42 of the cavity housing 22, and the flange 76 and the nub 72 abut the inner surface of the L-shaped flange 52.

[0065] Referring now to FIG.8, each input trace 27 is an elongate component formed of metal. The input trace 27 comprises a vertical panel 80 with a contact finger 82 extending inwardly from a lower edge therefrom. As can be seen in FIGS. 18 and 19, the upper and lower edges of the vertical panel 80 are captured by the ridges 74, 75 of the input trace holder 26. The fingers 82 extend through the vertical slots 54 in the outer walls 44 to engage and create electrical contact with the phase shifter PCBs 28.

[0066] Referring now to FIGS. 14-16, an exemplary feed stalk 30 is shown therein. The feed stalk 30 includes a PCB 90 that has metal traces 92, 94 on one side thereof. The opposite side of the PCB 90 has a metal ground layer that is covered with a thin solder mask. A metal ground plate 96 overlies the opposite side of the PCB 90 and provides a capacitive ground therewith. As shown in FIG. 14, the ground plate 96 includes a main body 99 and a flange 101 that arcs away from the main body 99 to a horizontal disposition. A gasket 110 is sandwiched between the flange 101 and the ceiling 46 of the cavity housing 22 to create a capacitive electrical connection between the cavity housing 22 and the ground plate 96.

[0067] Referring now to FIGS.10-12, a plastic stalk holder 98 is mounted on the ceiling 46 of the cavity housing 22. The stalk holder 98 has an upper block 100 with a slot 102 therein that receives the PCB 90 and the main body 99 of the groundAttorney Docket No.9833.7336.WO plate 96 of the feed stalk 30. Two slots 101 extend vertically through the upper block 100. A mounting panel 106 is positioned below the upper block 100 and extends away from the upper block 100 to overlie the ceiling 46 of the cavity housing 22. The mounting panel 106 also has a recess 107 in its lower surface that is contiguous with the slot 102.

[0068] The flange 101 of the ground plate 96 is positioned in the recess 107. Capture ridges 104 extend downwardly from the mounting panel 106 to receive the upper edges of the phase shifter PCBs 28 (see FIGS. 18 and 19). Rivets 112 pass through the mounting panel 106, the flange 101, and the gasket 110 to fasten the stalk holder 98 and the ground plate 96 to the ceiling 46.

[0069] Referring now to FIGS. 12 and 15-17, each of the feed stalks 30 is mounted to the antenna and connected to the phase shifter PCBs 28 via clips 120. As seen in FIG.17, each clip 120 includes opposing fingers 120f that are configured to receive the upper edge of one of the phase shifter PCBs 28. Also, each clip includes two wings 120w, each of which extends laterally from one of the fingers 120f.

[0070] The assembly of the antenna 20 can be envisioned by reference to the figures. As an initial step, each of the phase shifter PCBs 28 are inserted lengthwise into a respective cavity 24. The input traces 27 are mounted onto the input trace holders 26, with the input trace 27 being held in place as shown in FIGS.18 and 19. The input trace holders 26 (with the input traces 27 mounted therein) are then mounted to the cavity housing 22, with the nub 78 of the input trace holder 26 being received in the recesses 51 in the L-shaped flanges 52 of the cavity housing 22 (see FIGS.6-8, 23 and 24). The contact fingers 82 extend through the vertical slots 54 in the outer walls 42 of the cavity housing 22 to establish mechanical and electrical contact with the phase shifter PCBs 28 (see FIG.23), with the electrical contact inAttorney Docket No.9833.7336.WO some embodiments being a capacitive coupling (due to a thin layer of solder mask on the contact of the PCB 28). In the illustrated embodiment, a coaxial cable 130 is connected with each input trace 27 with a cable transition block 128 mounted to the outer wall 42 and the input trace holder 26 (see FIG. 25). The inner conductor of the cable 130 is soldered to the input trace 27, and the outer conductor of the cable 130 is soldered to the cable transition block 128.

[0071] Next, the feed stalks 30 and ground plates 96 are each individually mounted into respective stalk holders 98 (see FIG.13). Then each feed stalk 30 and ground plate 96 is lowered through one of the transverse slots 53 in the ceiling 46 of the cavity housing 22, with the stalk holder 98 resting on the upper surface of the ceiling 46 (FIGS.13 and 18-22). Two clips 120 are already in place (FIG.12), with the wings 120w of each within the slot 102 and contacting a contact pad on the feed stalk 30 (FIGS.15 and 16), and the fingers 120f residing in the slots 101 and, once lowered into place, making contact with contact pads on one of the phase shifter PCBs 28 (FIGS.18, 19 and 22). The upper edges of the phase shifter PCBs 28 are positioned within pairs of capture ridges 104 (FIGS. 18 and 19). This mounting establishes mechanical and electrical connection between the feed stalks 30 and ground plates 96 and the phase shifter PCBs 28. (Any or all of the contacts with contact pads discussed above may be capacitive contacts created via a thin layer of solder mask on the contact pads).

[0072] Once the feed stalks 30 and their accompanying ground plates 96 and stalk holders 98 are mounted on the cavity housing 22, the rivets 112 (e.g., push-in plastic rivets) are used to fix the stalk holder 98 (and in turn the feed stalk 30 and the grounding plate 96) to the ceiling 46 of the cavity housing 22 (FIG.20). A reflector 150 is then overlain onto the ceiling 46 of the cavity housing 22 (FIGS.23 and 24). The reflector 150 includes longitudinal slots 152 (FIG.26) through which the feedAttorney Docket No.9833.7336.WO stalks 30 and ground plates 96 pass. The reflector 150 is fixed in place with rivets 154 (e.g., plastic push-in rivets) that are inserted through the reflector 150 and into the ceiling 46 (FIG.19).

[0073] FIGS. 28 and 29 illustrate that the base station antenna 170 may also include a calibration PCB 190 attached at one end below the reflector 150

[0074] The foregoing demonstrates that the antenna 20 can be assembled with very little soldering (as described above, soldering is limited to the attachment of the coaxial cable 130 to the input trace 27 and the transition block 132). The other electrical connections are made via mechanical engagement of components: (a) the input trace 27 is connected with the phase shifter PCBs 28 via engagement of the contact fingers 82; (b) the phase shifter PCBs 28 are connected with the feed stalks 30 via the clips 120; and (c) the reflector 150 is connected to the cavity housing via the rivets 154 (wherein any or all of these connections may be capacitive connections). Minimizing soldering can help to provide a more “eco-friendly” manufacturing process.

[0075] Those of skill in this art will appreciate that the antenna 20 may be configured differently. For example, referring to FIGS.30A-C, an alternative linear array 220 is shown therein. The input trace 227 is configured as a straight metal bar. Contact fingers 282 are formed as separate pieces that extend between the input trace 227 and the phase shifter PCB 228. A plastic retainer 250 holds the contact finger 282 and slides upwardly into position, where it engages with the input trace shoulder 226 to maintain the contact finger 282 in its correct position. Alternatively, as shown in FIGS. 31A-C, the input trace 227’ may be a straight metal bar similar to input trace 227, but the contact finger 282’ may be held in place by a separate retainer 250 that is shaped in profile like the input trace holder. In each of these embodiments the soldering steps needed to provide connections are very limited.Attorney Docket No.9833.7336.WO

[0076] The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention.

Claims

Attorney Docket No.9833.7336.WO What is Claimed is:

1. An assembly for a radio frequency antenna, comprising: a cavity housing having a ceiling, a first side wall, and a dividing panel, wherein the ceiling, the dividing panel and the first side wall define a first cavity; a first phase shifter printed circuit board (PCB) mounted in the first cavity; a first input trace holder mounted to the cavity housing outside the first cavity; a first input trace mounted in the first input trace holder, the first input trace electrically connected with the first phase shifter PCB via a first finger extending through the first side wall and engaging the first phase shifter PCB; and a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing and electrically connected with the first phase shifter PCB and with the cavity housing.

2. The assembly defined in Claim 1, wherein the first finger is unitarily formed with the first input trace.

3. The assembly defined in Claim 1, wherein the first finger is a separate and distinct component from the first input trace.

4. The assembly defined in Claim 3, wherein the first finger is mounted in a retainer that is mounted in the input trace holder.

5. The assembly defined in Claim 1, wherein the cavity housing includes a first L-shaped flange mounted to the first side wall, and wherein the first input trace holder is mounted to the first L-shaped flange and to the first side wall.Attorney Docket No.9833.7336.WO 6. The assembly defined in Claim 1, wherein each of the feed stalks is electrically connected to the first phase shifter PCB via a first clip.

7. The assembly defined in Claim 1, wherein each of the feed stalks is electrically connected to the ceiling via a ground plate that partially overlies the ceiling.

8. The assembly defined in Claim 7, wherein each of the feed stalks is mounted to the ceiling via a feed stalk holder, the feed stalk holder at least partially overlying the ground plate.

9. The assembly defined in Claim 1, wherein the electrical connection between the first input trace and the first phase shifter PCB is devoid of a solder joint.

10. The assembly defined in Claim 1, wherein the electrical connection between the feed stalks and the first phase shifter PCB is devoid of a solder joint.

11. An assembly for a radio frequency antenna, comprising: a cavity housing having a ceiling, first and second side walls, and a dividing panel between the first and second side wall, wherein the ceiling, the dividing panel and the first side wall define a first cavity, and the ceiling, the dividing panel, the second side wall define a second cavity; first and second phase shifter printed circuit boards (PCBs) mounted in, respectively, the first and second cavities; first and second input trace holders mounted to the cavity housing outside, respectively, the first and second cavities;Attorney Docket No.9833.7336.WO first and second input traces mounted in, respectively, the first and second input trace holders, each of the first and second input traces electrically connected with, respectively, the first and second phase shifter PCBs via first and second fingers extending through, respectively, the first and second side walls and engaging the first and second phase shifter PCBs; a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing and electrically connected with the first and second phase shifter PCBs and with the cavity housing; and a reflector that overlies the ceiling of the reflector, the feed stalks extending through slots in the reflector.

12. The assembly defined in Claim 11, wherein the first finger is unitarily formed with the first input trace.

13. The assembly defined in Claim 11, wherein the first finger is a separate and distinct component from the first input trace.

14. The assembly defined in Claim 13, wherein the first finger is mounted in a retainer that is mounted in the input trace holder.

15. The assembly defined in Claim 11, wherein the cavity housing includes first and second L-shaped flanges mounted to, respectively, the first and second side walls, and wherein the first and second input trace holders are mounted to the first and second L-shaped flanges and to the first and second side walls.Attorney Docket No.9833.7336.WO 16. The assembly defined in Claim 11, wherein each of the feed stalks is electrically connected to the first and second phase shifter PCBs via first and second clips.

17. The assembly defined in Claim 11, wherein each of the feed stalks is electrically connected to the ceiling via a ground plate that partially overlies the ceiling.

18. The assembly defined in Claim 17, wherein each of the feed stalks is mounted to the ceiling via a feed stalk holder, the feed stalk holder at least partially overlying the ground plate.

19. The assembly defined in Claim 11, wherein the electrical connection between the first input trace and the first phase shifter PCB is devoid of a solder joint.

20. The assembly defined in Claim 11, wherein the electrical connection between the feed stalks and the first phase shifter PCB is devoid of a solder joint.

21. An assembly for a radio frequency antenna, comprising: a cavity housing having a ceiling, a first side wall, and a dividing panel, wherein the ceiling, the dividing panel and the first side wall define a first cavity; a first phase shifter printed circuit board (PCB) mounted in the first cavity; a first input trace holder mounted to the cavity housing outside the first cavity; a first input trace mounted in the first input trace holder, the first input trace electrically connected with the first phase shifter PCB; a plurality of feed stalks, each of the feed stalks mounted on the ceiling of the cavity housing, each of the feed stalks electrically connected with the first phaseAttorney Docket No.9833.7336.WO shifter PCB via a mechanical clip, each of the feed stalks also electrically connected with the cavity housing.

22. An antenna, comprising: an assembly as defined in any of Claims 1-21; and a reflector that overlies the ceiling of the cavity housing, the feed stalks extending through slots in the reflector.

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