Patent Grant
11575217
The present invention generally relates to radio communications and, more particularly, to base station antennas for cellular communications systems.
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. The base station may include one or more 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. In many cases, each cell is divided into “sectors.” In one common configuration, a hexagonally shaped cell is divided into three 120° sectors in the azimuth plane, and each sector is served by one or more base station antennas that have an azimuth Half Power Beamwidth (HPBW) of approximately 65°. 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. Base station antennas are often implemented as linear or planar phased arrays of radiating elements.
In order to accommodate the increasing volume of cellular communications, cellular operators have added cellular service in a variety of new frequency bands. While in some cases it is possible to use a single linear array of so-called “wide-band” radiating elements to provide service in multiple frequency bands, in other cases it is necessary to use different linear arrays (or planar arrays) of radiating elements to support service in the different frequency bands.
As the number of frequency bands has proliferated, and increased sectorization has become more common (e.g., dividing a cell into six, nine or even twelve sectors), the number of base station antennas deployed at a typical base station has increased significantly. However, due to, for example, local zoning ordinances and/or weight and wind loading constraints for the antenna towers, there is often a limit as to the number of base station antennas that can be deployed at a given base station. In order to increase capacity without further increasing the number of base station antennas, multi-band base station antennas have been introduced which include multiple linear arrays of radiating elements. One common multi-band base station antenna design includes two linear arrays of “low-band” radiating elements that are used to provide service in some or all of the 617-960 MHz frequency band and two linear arrays of “mid-band” radiating elements that are used to provide service in some or all of the 1427-2690 MHz frequency band. The four linear arrays are mounted in side-by-side fashion. There is also interest in deploying base station antennas that include one or more linear arrays of “high-band” radiating elements that operate in higher frequency bands, such as some or all of the 3.3-4.2 GHz frequency band. As larger numbers of linear arrays are included in base station antennas, it becomes more difficult, time-consuming and expensive to design, fabricate and test these antennas.
Pursuant to embodiments of the present invention, base station antennas are provided that include a first backplane that includes a first reflector, a vertically-extending array of first radiating elements mounted to extend forwardly from the first reflector, at least one first RF port that is coupled to the vertically-extending array of first radiating elements, and a sub-module that is attached to the first backplane. The sub-module includes a second backplane that includes a second reflector that is separate from the first reflector, a vertically-extending array of second radiating elements that is transversely spaced-apart from the vertically-extending array of first radiating elements, the second radiating elements mounted to extend forwardly from the second reflector, and a plurality of second RF ports that are coupled to the vertically-extending array of second radiating elements. The first radiating elements and the second radiating elements are configured to serve a common sector of a base station that includes the base station antenna.
In some embodiments, the sub-module may be configured to slidably mate with the first backplane prior to being attached thereto.
In some embodiments, at least one guide may extend forwardly from the first reflector and the second reflector includes a rail that is configured to slidably mate with the at least one guide.
In some embodiments, the second backplane includes a first transversely-extending projection that is configured to slide along a rear surface of the first reflector when the sub-module is slidably mated with the first backplane and a second transversely-extending projection that is configured to slide along a front surface of the first reflector when the sub-module is slidably mated with the first backplane. In such embodiments, a first insulating spacer may be interposed between first transversely-extending projection and the first reflector and a second insulating spacer may be interposed between second transversely-extending projection and the first reflector.
In some embodiments, a stop feature may extend forwardly from the first reflector.
In some embodiments, the second reflector may be positioned forwardly of the first reflector.
In some embodiments, the second reflector may be coplanar with the first reflector.
In some embodiments, the sub-module may further include a phase shifter coupled between the second RF ports and the vertically-extending array of second radiating elements. The phase shifter may be mounted on a rear side of the second backplane.
In some embodiments, the vertically-extending array of second radiating elements may be one of a plurality of vertically-extending linear arrays of second radiating elements included in the sub-module, and the sub-module may further include a calibration circuit that is coupled between the second RF ports and the vertically-extending array of second radiating elements.
In some embodiments, the sub-module may further include a phase shifter coupled between the second RF ports and the vertically-extending array of second radiating elements.
In some embodiments, the base station antenna may further include a first end plate that extends both forwardly and rearwardly along a lower edge of the first reflector, and an end cap that covers the first end plate. In some embodiments, the sub-module may include a second end plate that extends both forwardly and rearwardly along a lower edge of the second reflector. In some embodiments, the first end plate includes an opening, and the second end plate is received within the opening
In some embodiments, the base station antenna may further include a vertically-extending array of third radiating elements mounted to extend forwardly from the first reflector, and the vertically-extending array of second radiating elements may be positioned between the vertically-extending array of first radiating elements and the vertically-extending array of third radiating elements.
In some embodiments, the periphery of the first reflector may define a footprint when viewed along an axis that is perpendicular to the first reflector, and at least some of the second radiating elements may be within the footprint.
In some embodiments, the sub-module may be attached to the first backplane via a plurality of fasteners.
Pursuant to further embodiments of the present invention, base station antennas are provided that include a first backplane that includes a first reflector, a vertically-extending array of first radiating elements mounted to extend forwardly from the first reflector, a sub-module that includes a second reflector, the sub-module slidably mated with the first backplane, and a vertically-extending array of second radiating elements mounted to extend forwardly from the second reflector.
In some embodiments, the vertically-extending array of second radiating elements may be transversely spaced-apart from the vertically-extending array of first radiating elements.
In some embodiments, the second reflector may extend in parallel to the first reflector.
In some embodiments, the second reflector may be coplanar with the first reflector.
In some embodiments, the sub-module may further include a sub-module end plate that is mounted at the bottom of the second reflector, and a plurality of RF ports that are mounted in the sub-module end plate.
In some embodiments, at least one guide may extend forwardly from the first reflector and the second reflector may include a rail that is configured to slidably mate with the at least one guide.
In some embodiments, the second reflector may be part of a second backplane, and the second backplane may include a first transversely-extending projection that is configured to slide along a rear surface of the first reflector when the sub-module is slidably mated with the first backplane and a second transversely-extending projection that is configured to slide along a front surface of the first reflector when the sub-module is slidably mated with the first backplane.
In some embodiments, a first insulating spacer may be interposed between first transversely-extending projection and the first reflector and a second insulating spacer may be interposed between second transversely-extending projection and the first reflector.
In some embodiments, the second reflector may be part of a second backplane and the sub-module may further include a phase shifter coupled between a first of the second RF ports and the vertically-extending array of second radiating elements, where the phase shifter is mounted on a rear side of the second backplane.
In some embodiments, the sub-module may further include a plurality of RF ports, and the vertically-extending array of second radiating elements is one of a plurality of vertically-extending linear arrays of second radiating elements included in the sub-module, and the sub-module further includes a calibration circuit that is coupled between the RF ports and the vertically-extending array of second radiating elements.
In some embodiments, the base station antenna may further include a main end plate that extends both forwardly and rearwardly along a lower edge of the first reflector, and an end cap that covers the main end plate.
In some embodiments, the sub-module may further include a sub-module end plate that is mounted at the bottom of the second reflector, and a plurality of RF ports that are mounted in the sub-module end plate, and the main end plate may include an opening, and the sub-module end plate may be received within the opening.
In some embodiments, the periphery of the first reflector defines a footprint when viewed along an axis that is perpendicular to the first reflector, and at least some of the second radiating elements are within the footprint.
In some embodiments, the second reflector may be positioned forwardly of the first reflector.
Pursuant to still further embodiments of the present invention, base station antennas are provided that include a first backplane that includes a first reflector, a vertically-extending array of first radiating elements mounted to extend forwardly from the first reflector, and a sub-module that is attached by a plurality of fasteners to the first backplane. The sub-module includes a second reflector that is mounted forwardly of the first reflector, a vertically-extending array of second radiating elements that is transversely spaced-apart from the vertically-extending array of first radiating elements, the second radiating elements mounted to extend forwardly from the second reflector, and a plurality of RF ports that are coupled to the vertically-extending array of second radiating elements.
In some embodiments, the second reflector may be coplanar with the first reflector.
In some embodiments, the sub-module may be configured to slidably mate with the first backplane prior to being attached thereto.
In some embodiments, at least one guide may extend forwardly from the first reflector and the second reflector may include a rail that is configured to slidably mate with the at least one guide.
In some embodiments, the second reflector may be part of a second backplane that includes a first transversely-extending projection that is configured to slide along a rear surface of the first reflector when the sub-module is slidably mated with the first backplane and a second transversely-extending projection that is configured to slide along a front surface of the first reflector when the sub-module is slidably mated with the first backplane.
In some embodiments, the periphery of the first reflector may define a footprint when viewed along an axis that is perpendicular to the first reflector, and at least some of the second radiating elements may be within the footprint.
In some embodiments, the sub-module may further include a phase shifter coupled between the RF ports and the vertically-extending array of second radiating elements.
In some embodiments, the vertically-extending array of second radiating elements may be one of a plurality of vertically-extending linear arrays of second radiating elements included in the sub-module, and the sub-module may further include a calibration circuit that is coupled between the RF ports and the vertically-extending array of second radiating elements.
In some embodiments, the vertically-extending array of second radiating elements may comprise four vertically-extending linear arrays of radiating elements that are configured as a beamforming array.
Pursuant to still further embodiments of the present invention, base station antenna assemblies are provided that include a base station antenna having a frame, a radome that covers the frame, and a bottom end cap, and a radio mounted to the frame on a rear side of the base station antenna. The bottom end cap includes a plurality of upwardly extending connector ports.
In some embodiments, the bottom end cap includes a rearwardly-extending lip that extends further rearwardly than the radome, and the connector ports are mounted to extend upwardly from a top surface of the rearwardly-extending lip.
In some embodiments, the radio may be a beamforming radio that includes a plurality of downwardly-extending radio connector ports that face the connector ports that extend upwardly from a top surface of the rearwardly extending lip.
Pursuant to still further embodiments of the present invention, base station antenna assemblies are provided that include a base station antenna having a frame and a radome that covers the frame, and first and second radios mounted on the frame on a rear side of the base station antenna, with the second radio mounted above the first radio. A rear surface of the radome includes a first opening, and a plurality of connector ports extend through the first opening.
In some embodiments, a panel may be mounted in the first opening, and the plurality of connector ports may be mounted in the panel.
In some embodiments, the first opening may be located above the first radio and below the second radio.
In some embodiments, the base station antenna assembly may further include a second opening that is located below the first radio.
In some embodiments, the base station antenna assembly may further include a second opening that is located above the second radio.
In some embodiments, the base station antenna assembly may further include a second opening that is located above the first opening and below the second radio.
In some embodiments, the base station antenna assembly may further include a cover that covers both the plurality of connector ports and a plurality of radio connector ports on the first radio.
In some embodiments, the cover may include a plurality of heat vents.
In some embodiments, the base station antenna assembly may further include a baffle that that is positioned between the first radio and the second radio. The baffle may be configured to direct heat generated by the first radio away from the second radio.
In some embodiments, the first radio may be mounted on a plate, and the plate may be attached to the base station antenna by at least one guide rail that cooperates with one or more guide structures.
In some embodiments, the guide rail may include a slot.
In some embodiments, the slot may have a generally C-shaped cross-section.
In some embodiments, the one or more guide structures may comprise a plurality of wheels that are mounted on respective posts.
In some embodiments, the one or more guide structures may comprise a rod.
In some embodiments, the guide rail may be mounted on the base station antenna and the one or more guide structures may be mounted on the plate opposite the first radio.
Pursuant to still further embodiments of the present invention, base station antenna assemblies are provided that include a base station antenna having a frame and a radome that covers the frame, and a first radio mounted on a radio support plate that is attached to the frame on a rear side of the base station antenna. A first guide rail is mounted on one of the base station antenna and the plate and one or more cooperating guide structures are mounted on the other of the base station antenna and the radio support plate, where the guide rail and the one or more cooperating guide structures are configured so that when the one or more cooperating guide structures are received within a slot in the guide rail the radio support plate is mounted on the base station antenna.
In some embodiments, the slot may have a generally C-shaped cross-section.
In some embodiments, the one or more guide structures may comprise a plurality of wheels that are mounted on respective posts.
In some embodiments, the one or more guide structures may comprise a rod.
In some embodiments, the guide rail may be mounted on the base station antenna and the one or more guide structures may be mounted on the radio support plate opposite the first radio.
In some embodiments, the base station antenna assembly may further include a jumper cable assembly that includes a plurality of connectorized jumper cables, and a first connector of each jumper cable may be a blind mate connector.
In some embodiments, the first connector of each jumper cable may be mounted in respective openings in a mounting plate, and the openings may be arranged in a pattern identical to a pattern of the radio connector ports on the first radio.
In some embodiments, a second connector of each jumper cable may comprise a blind mate connector.
Pursuant to still further embodiments of the present invention, base station antenna assemblies are provided that include a base station antenna having a frame, a radome that covers the frame, and a bottom end cap, a first radio mounted to the frame on a rear side of the base station antenna, and a second radio mounted to the frame on a rear side of the base station antenna above the first radio. A rear surface of the radome includes a first opening, and a panel having a plurality of access holes is mounted in the first opening, and a plurality of connectorized cables extend from the interior of the base station antenna through respective ones of the access holes.
Pursuant to embodiments of the present invention, reconfigurable multi-band antennas are provided that include one or more self-contained sub-modules. These antennas may include a main module and at least one self-contained sub-module that may be attached to the main module. The main module includes at least a first array of radiating elements and the sub-module includes at least a second array of radiating elements. The sub-module may be completely self contained in that the RF paths between the one or more arrays of radiating elements included in the sub-module and the one or more RF ports that connect those arrays of radiating elements to a radio are contained within the sub-module. Thus, the sub-module may include, for example, the RF ports associated with the sub-module arrays, the RF transmission paths that extend between the RF ports and the radiating elements, and any phase shifters, power splitter/combiners, diplexers and the like that are included along the RF paths. If the sub-module includes arrays of radiating elements that are used to perform beamforming, then the sub-module may further include a calibration port along with appropriate calibration circuitry. The sub-module may optionally include other elements, such as, for example, RET actuators and/or mechanical linkages for any phase shifters included in the sub-module, although these components may alternatively be included in the main module and connected to the sub-module or omitted altogether. Each sub-module may have its own backplane and reflector that may be configured to optimize the performance of the sub-module.
In some embodiments, the sub-module may slidably mate with the main module. In other embodiments, the sub-module may simply be placed in or on the main module and fixed in place.
The antennas according to embodiments of the present invention that include self-contained sub-modules may have a number of advantages as compared to conventional antennas. First, since the sub-modules contain the complete RF path between the RF ports and the radiating elements, each sub-module may be fabricated and tested independently of any other sub-modules and the main module of an antenna. This allows various parts of the antenna to be fabricated and tested in parallel, which may reduce manufacturing time. Additionally, if some aspect of the sub-module needs to be redesigned, adjusted or replaced, then this work may be performed without any need to change the main module of the antenna. The sub-module approach also makes it easy to change various aspects of the sub-module, such as the distance of the sub-module reflector from the radome without impacting the remainder of the antenna design. The sub-module approach also makes the antenna reconfigurable, as a first sub-module may be taken out of the antenna and replaced with a different sub-module (e.g., a sub-module with a different configuration of arrays operating in different frequency bands) in order to change the capabilities of the antenna. The sub-module approach may be particularly advantageous with antennas that include beamforming capabilities, as the testing and calibration of the beamforming capabilities may be performed before the sub-module is mated with the remainder of the antenna.
In some embodiments, the base station antennas include a main module that has a first backplane that includes a first reflector. A vertically-extending array of first radiating elements is mounted to extend forwardly from the first reflector, and at least one first RF port is coupled to the vertically-extending array of first radiating elements. These antennas further include a sub-module that is attached to the first backplane. The sub-module includes a second backplane that has a second reflector that is separate from the first reflector. A vertically-extending array of second radiating elements is mounted to extend forwardly from the second reflector and is transversely spaced-apart from the vertically-extending array of first radiating elements. A plurality of second RF ports are coupled to the vertically-extending array of second radiating elements. The vertically-extending array of first radiating elements and the vertically-extending array of second radiating elements are configured to serve a common sector of a base station. For example, both arrays may be configured to provide coverage to a common 120° sector in the azimuth plane.
In other embodiments, the base station antennas include a first backplane that includes a first reflector. A vertically-extending array of first radiating elements may be mounted to extend forwardly from the first reflector. These antennas further include a sub-module that has a second reflector. The sub-module is slidably mated with the first backplane. A vertically-extending array of second radiating elements is mounted to extend forwardly from the second reflector.
In yet other embodiments, the base station antennas include a first backplane that includes a first reflector and a vertically-extending array of first radiating elements are mounted to extend forwardly from the first reflector. These antennas further include a sub-module that is attached by a plurality of fasteners to the first backplane. The sub-module includes a second reflector that is mounted forwardly of the first reflector so that the second reflector is closer to a front surface of the radome than is the first reflector. The sub-module further includes a vertically-extending array of second radiating elements that is mounted to extend forwardly from the second reflector and a plurality of second RF ports that are coupled to the vertically-extending array of second radiating elements so that the sub-module is a self-contained sub-module that includes the complete RF path for the vertically-extending array of second radiating elements. The vertically-extending arrays of first and second radiating elements may be is transversely spaced-apart from one another.
Embodiments of the present invention will now be described in further detail with reference to the attached figures.
Referring first to
The main backplane 210 defines a main module of the antenna assembly 200. One or more self-contained sub-modules 300 (
The main reflector 214 may comprise a generally flat metallic surface that extends in the longitudinal direction L of the antenna 100. Some of the radiating elements (discussed below) of the antenna 100 may be mounted to extend forwardly from the main reflector 214, and the dipole radiators of these radiating elements may be mounted approximately ¼ of a wavelength of the operating frequency for each radiating element forwardly of the main reflector 214. The main reflector 214 may serve as a reflector and as a ground plane for the radiating elements of the antenna 100 that are mounted thereon.
As shown in
The first mid-band radiating elements 232 may likewise be mounted to extend upwardly from the main reflector 214 and may be mounted in two columns to form two linear arrays 230-1, 230-2 of first mid-band radiating elements 232. The linear arrays 230-1, 230-2 of mid-band radiating elements 232 may extend along the respective side edges of the main reflector 214. The first mid-band radiating elements 232 may be configured to transmit and receive signals in a second frequency band. In some embodiments, the second frequency band may comprise the 1427-2690 MHz frequency range or a portion thereof (e.g., the 1710-2200 MHz frequency band, the 2300-2690 MHz frequency band, etc.). In the depicted embodiment, the first mid-band radiating elements 232 are configured to transmit and receive signals in the lower portion of the second frequency band (e.g., some or all of the 1427-2200 MHz frequency band). The linear arrays 230-1, 230-2 of first mid-band radiating elements 232 may be configured to transmit and receive signals in the same portion of the second frequency band or in different portions of the second frequency band
The second mid-band radiating elements 242 are mounted in four columns in the upper center portion of antenna 100 to form four linear arrays 240-1 through 240-4 of second mid-band radiating elements 242. The second mid-band radiating elements 242 may be configured to transmit and receive signals in the second frequency band. In the depicted embodiment, the second mid-band radiating elements 242 are configured to transmit and receive signals in an upper portion of the second frequency band (e.g., some or all of the 2300-2700 MHz frequency band). In the depicted embodiment, the second mid-band radiating elements 242 may have a different design than the first mid-band radiating elements 232.
The high-band radiating elements 252 are mounted in four columns in the lower center portion of antenna 100 to form four linear arrays 250-1 through 250-4 of high-band radiating elements 252. The high-band radiating elements 252 may be configured to transmit and receive signals in a third frequency band. In some embodiments, the third frequency band may comprise the 3300-4200 MHz frequency range or a portion thereof.
In other embodiments, the number of linear arrays of low-band, mid-band and high-band radiating elements may be varied from what is shown in
In the depicted embodiment, the low-band and mid-band radiating elements 222, 232, 242 may each be mounted to extend forwardly from the main reflector 214. The high-band radiating elements 252 may each be mounted to extend forwardly from a sub-module reflector, as will be described in further detail below.
Each array 220-1, 220-2 of low-band radiating elements 222 may be used to form a pair of antenna beams, namely an antenna beam for each of the two polarizations at which the dual-polarized radiating elements are designed to transmit and receive RF signals. Likewise, each array 232 of first mid-band radiating elements 232, each array 242 of second mid-band radiating elements 242, and each array 252 of high-band radiating elements 252 may be configured to form a pair of antenna beams, namely an antenna beam for each of the two polarizations at which the dual-polarized radiating elements are designed to transmit and receive RF signals. Each linear array 220, 230, 240, 250 may be configured to provide service to a sector of a base station. For example, each linear array 220, 230, 240, 250 may be configured to provide coverage to approximately 120° in the azimuth plane so that the base station antenna 100 may act as a sector antenna for a three sector base station. Of course, it will be appreciated that the linear arrays may be configured to provide coverage over different azimuth beamwidths. While all of the radiating elements 222, 232, 242, 252 are dual-polarized radiating elements in the depicted embodiment, it will be appreciated that in other embodiments some or all of the dual-polarized radiating elements may be replaced with single-polarized radiating elements. It will also be appreciated that while the radiating elements are illustrated as dipole radiating elements in the depicted embodiment, other types of radiating elements such as, for example, patch radiating elements may be used in other embodiments.
As shown best in
As noted above, the base station antennas according to embodiments of the present invention may be reconfigurable antennas that include one or more self-contained sub-modules. The base station antenna 100 includes one such sub-module 300.
As shown in
As shown in
Provision of the end plate 260 avoids any need to separate the bottom end cap 130 into two pieces, and hence provision of the end plate 260 makes it easy to use a standard one-piece bottom end cap 130. This may improve the ability of the antenna 100 to resist water/moisture ingress. The end plate 260 may be formed of a non-metal material (e.g., plastic) to avoid adding any additional metal-to-metal connections which may be potential source of passive intermodulation (“PIM”) distortion.
As shown in
The rear surface of the sub-module reflector 314 and the sidewalls 312 may define a chamber 316. A sub-module end plate 320 may be mounted on the bottom end of the sub-module 300. The sub-module end plate 320 may include a plurality of openings 322. Various connectors 330, 332 may be mounted in the openings 322. In particular, eight RF connectors or “ports” 330 may be provided that are used to couple high-band RF signals between a high-band radio (not shown) and the linear arrays 250 of high-band radiating elements 250 included in sub-module 300. Two RF ports are provided for each high-band linear array 250, namely a first RF port 330 that couples first polarization high-band RF signals between the high-band radio and the linear array 250 and a second RF port 330 that couples second polarization high-band RF signals between the high-band radio and the linear array 250. As the radiating elements 252 are slant cross-dipole radiating elements, the first and second polarizations may be a −45° polarization and a +45° polarization.
As shown best in
As shown in
As shown in
Notably, the sub-module 300 may comprise a self-contained sub-module that includes all of components of antenna 100 that are along the RF paths for the four high-band linear arrays 250 that are included in the sub-module 300. Consequently, the sub-module 300 may be fully operable to transmit and receive RF signals regardless of whether or not the sub-module 300 is mounted within the remainder of antenna 100. This may be highly advantageous as it allows the sub-module 300 to be tested and calibrated separately from the remainder of antenna 100. For example, if the sub-module 300 includes a beamforming antenna (as in the case of the antenna 100), then a calibration process must be performed to determine differences in the amplitude and/or phase along the RF paths so that these differences can be accommodated for by the radio. This calibration process may be performed after the sub-module 300 is fabricated but before the sub-module 300 is mated with the remainder of antenna 100. Likewise, various RF tests are performed for each linear array in order to identify any potential problems such as, for example, PIM sources along the RF path, faulty connections, misaligned elements and the like so that these problems may be corrected. Once again, since the sub-module 300 is self-contained, these tests and any necessary reworking of the sub-module 300 may be performed before the sub-module 300 is mated with the remainder of the antenna 100.
As shown in
As can best be seen in
As shown in
As can be seen in
In other embodiments, the stop 219 may be formed by mounting a forwardly-extending structure on the main reflector 214 instead of by forming upwardly (or downwardly) extending tabs in the main reflector 214.
As shown in
An insulating spacer 319 (
As shown in
Typically, the calibration circuit 340 of a beamforming antenna is interposed on the electrical paths between the RF ports 330 and the phase shifters 342, as is schematically shown in
While the antennas discussed above include main backplanes that include a lower end plate, and a one-piece bottom end cap 130 that covers the lower end plate, it will be appreciated that embodiments of the present invention are not limited thereto. For example, in other embodiments, the lower end plate may be omitted, and a bottom end cap 130′ may be provided that includes two separate pieces 132, 134, as shown in
It will also be appreciated that the sub-module need not be configured to slidably mate with the remainder of the antenna assembly. For example, in some embodiments, the sub-module may simply be placed on the main reflector and secured in place using, for example, fasteners. Such a design may be simpler and cheaper to implement. However, in some antennas, there may not be sufficient room to directly place the sub-module onto the main reflector in this fashion (i.e., without sliding) because some of the radiating elements may overlie the sub-module reflector in the completed antenna, and hence prevent simply placing the sub-module on the main reflector. This is the case, for example, with the base station antenna 100, as
The use of self-contained sub-modules may be particularly advantageous with respect to beamforming antennas, as beamforming antennas require additional calibration steps that increase the time required to configure the antenna. By forming some or all of the beamforming portion of a multi-band antenna using self-contained sub-modules, each sub-module may be calibrated and tested separately, allowing the calibration and test operations to be performed in parallel and hence completed more quickly. It may also be much easier to rework components of the sub-module that fail such tests, as technicians have ready access to the rear side of the sub-module reflector and the components mounted thereon. Thus, for example, it may be much easier to remove and replace faulty solder joints in a sub-module according to embodiments of the present invention.
Pursuant to further embodiments of the present invention, base station antennas are provided which have one or more radios mounted on the back of the antenna to provide an antenna assembly. The base station antennas included in these antenna assemblies may have arrays of connector ports (or other connections) for the radios mounted on the rear surface of the base station antenna, which may provide both design and performance advantages. In some embodiments, the base station antennas may be designed so that radios manufactured by any original equipment manufacturer may be mounted on the back of the antenna. This allows cellular operators to purchase the base station antennas and the radios mounted thereon separately, providing greater flexibility to the cellular operators to select antennas and radios that meet operating needs, price constraints and other considerations. Various embodiments of these base station antennas will be discussed in further detail with reference to
Turning first to
As shown in
Referring to
The antenna assembly 500 of
One challenge in implementing the above-described base station antennas is that the number of RF connector ports included on the antenna is significantly increased. Whereas antennas having six, eight or twelve connector ports were common in the past, the new antennas may require far more RF connections. For example, the base station antenna 200 that is described above includes two linear arrays 220 of low-band radiating elements 222, two linear arrays 230 of first mid-band radiating elements 232, a four column planar array 240 of second mid-band radiating elements 242 and a four column planar array 250 of high-band radiating elements 252. All of the radiating elements 222, 232, 242, 252 may comprise dual-polarized radiating elements. Consequently, each column of radiating elements will be fed by two separate connector ports on a radio, and thus a total of twenty-four RF connector ports are required on the base station antenna 200 to pass RF signals between the twelve separate columns of radiating elements and their associated RF connector ports on the cellular radios. Moreover, each of the four column planar arrays of radiating elements 230, 240 are operated as a beamforming array, and hence a calibration connector port is required for each such array, raising the total number of RF connector ports required on the antenna to twenty-six. Additional control ports are also typically required which are used, for example to control electronic tilt circuits included in the antenna.
Conventionally, the above-described RF connector ports, as well as any control ports, have been mounted in the lower end cap of a base station antenna. Mounting the RF connector ports in this location can help locate the RF connector ports close to remote radio heads that are mounted separate from the antenna, which may improve the aesthetic appearance of the installed equipment and reduce RF cable losses. Additionally, mounting the RF connector ports to extend downwardly from the bottom end plate helps protect the base station antenna from water ingress through the RF connector ports and may shield the RF connector ports from rain.
Unfortunately, as the number of RF connector ports required in some base station antennas is increased, while the overall size of the antennas are kept relatively constant, the spacing between the RF connector ports on the bottom end cap may be reduced significantly. This can be seen, for example, in
As discussed above, in the antenna assembly 500 according to embodiments of the present invention, two arrays 534 of RF connector ports 532 are provided on the back surface of the base station antenna 510. One of the arrays 534 of connector ports 532 may comprise the RF connector ports 532 for the four column planar array 240 of second mid-band radiating elements 242 and the other array 534 of RF connector ports 532 may comprise the RF connector ports 532 for the four column planar array 250 of high-band radiating elements 252. As shown in
Moreover, in some embodiments, the base station antenna 510 may be designed so that radios 550 manufactured by a wide variety of different equipment manufacturers may be mounted thereon. For example, the frame of the base station antenna 510 (which is located inside the radome 520) may include rails or other vertically extending members along the back surface thereof that the radios 550 may be mounted on. This may allow a cellular operator to order a base station antenna 510 according to embodiments of the present invention from a first vendor, a first beamforming radio 550 from a second vendor and a second beamforming radio 550 from a third vendor and then combine the three together to form the antenna assembly 500. This provides significant flexibility to the cellular operator to select vendors and/or equipment that best suit the needs of the cellular operator.
The base station antenna 510 is configured so that the first array 534-1 of RF connector ports 532 is mounted near the bottom of the back surface of the radome 520, and the second array 534-2 of RF connector ports 532 is mounted near the middle of the back surface of the radome 520. The beamforming radios 550 are mounted above their corresponding arrays 534 of RF connector ports 532 in this design. It will be appreciated, however, that embodiments of the present invention are not limited to this configuration. For example,
As shown in
As discussed above, one of the potential advantages of the antenna assemblies 500 according to embodiments of the present invention is that they may allow for very short jumper cables 560 extending between the beamforming radios 550 and the base station antenna 510, which may significantly reduce RF cable losses. By deliberately selecting the location for the arrays 534 of RF connector ports 532, a similar reduction in RF cable losses may be obtained with respect to the internal jumper cables that connect the RF connector ports 532 to internal components of the base station antenna 510. For example, when the radios 550 are beamforming radios, the internal jumper cables will typically extend between the RF connector ports 532 and corresponding phase shifter or calibration circuits. Thus, if the arrays 534 of RF connector ports 532 are located to be near the corresponding phase shifter (or calibration board), short internal jumper cables may be used, further reducing RF cable losses.
While
The antenna assemblies according to embodiments of the present invention, such as antenna assembly 500, may also be designed so that the radios 550 may be field-replaceable. Herein, a field-replaceable radio refers to a radio 550 that is mounted on a base station antenna that can be removed and replaced with another radio while the base station antenna is mounted for use on, for example, an antenna tower. In order to facilitate such field-replaceable capabilities, the antenna assembly 500 may be designed so that the mounting brackets 570 that attach between the antenna assembly 500 and the antenna tower (or other mounting structure) connect to the base station antenna 510 as opposed to connecting to the radios 550. Additionally, as shown in
Referring next to
The various embodiments of the antenna assembly 500 illustrated with respect to
Pursuant to further embodiments of the present invention, the RF connectors 532 included in the antenna assembly 500 may be replaced with access holes.
It will be appreciated that many modifications may be made to the antenna assemblies described above without departing from the scope of the present invention. For example, while the above embodiments illustrate two radios mounted on the back of the antenna, it will be appreciated that in other embodiments different numbers of radios may be mounted on the antenna. For example, one, three, four or more radios may be mounted on the back of the antenna in other embodiments depending, for example, on cellular operator requirements. It will also be appreciated that while the beamforming antennas are shown mounted on the back of the antennas described above, embodiments of the present invention are not limited thereto. For example, in other embodiments, the radios that connect to the passive linear arrays may be mounted on the back of the antenna. However, in many instances it may be advantageous to mount the beamforming radios on the back of the antenna (which typically operate as time division duplexed radios) because these radios may be smaller and/or lighter weight than the radios that feed the passive, frequency division duplexed linear arrays 220, 230, and as the beamforming radios typically have more RF connector ports, and hence mounting the beamforming radios on the back of the antenna and moving the associated RF connector ports to the back of the antenna as well frees up more space on the bottom end cap, simplifying the installation process.
As another example, antenna assemblies according to embodiments of the present invention are discussed above that use jumper cable connections or blind mate connectors to electrically connect the beamforming radios to the base station antenna. As will be discussed in further detail below, it will be appreciated that in still further embodiments press-fit connectors may be used. Such press-fit connectors operate in a similar manner to the above-described blind-mate connectors, but the press-fit connectors may be visible to the technician during installation, making it easier to install the radios, particularly when the installation is performed at the top of an antenna tower.
Pursuant to still further embodiments of the present invention, filters may be added between at least some of the RF connector ports on the radios mounted on the antenna assemblies according to embodiments of the present invention and the RF connector ports on the antenna. In some countries, the frequency bands associated with certain cellular radios may be partially reserved for other uses. In such countries, only a portion of the frequency band may thus be used. One way to accommodate such requirements is to deploy radios that are designed to operate in only a portion of the frequency band. However, by adding external filters between the radio and the antenna, the need to replace the radio may be eliminated. Moreover, in some cases, the filters may be implemented as inline devices that may connect, for example, to the jumper cables or that may even be integrated into the jumper cables in some embodiments.
Pursuant to still further embodiments of the present invention, methods of installing beamforming radios on base station antennas to provide base station assemblies are provided. Methods of installation are provided that are suitable for factory installation as well as methods for field installing (or replacing) beamforming radios on base station antennas. In the discussion that follows the installation methods will primarily be described with reference to installing the beamforming radios 550 of
Referring to
As shown in
As shown in
Referring to
Referring to
Implementing the guide structures 830 as rotatable wheels 832 that are mounted on posts 834 may provide for a very low friction interface that may make it easier for an installer to mount the radio support plate 800 (with or without a beamforming radio 550 mounted thereon) on the base station antenna 510. However, it will be appreciated that a wide variety of other guide structures 830 could be used. For example,
The beamforming radios 550 may also be readily replaced in the field. As is well known, base station antennas are typically mounted on towers, often hundreds of feet above the ground. Base station antennas may also be large, heavy and mounted on antenna mounts that extend outwardly from the tower. As such, replacing base station antennas may be difficult and expensive. The beamforming radios 550 of base station antenna assembly 500 may be field replaceable without the need to detach the base station antenna 510 from an antenna mount. Instead, the jumper cables 560 that extend between the base station antenna 510 and the beamforming radios 550 may be removed, and any stop mechanisms such as stop bolts or latches that are used to hold each radio support plate 800 with a beamforming radio 550 mounted thereon in place (to prevent lateral movement of the radio support plate 800 relative to the radio 550) on the base station antenna 510 may also be removed or unlatched. Each radio support plate 800 with a beamforming radio 550 mounted thereon may then be removed simply by sliding the radio support plate 800 laterally until the guide structure(s) 830 are free of the slots 594 in the respective guide rails 590. Then, a different beamforming radio 550 that is mounted on an appropriate radio support plate 800 may be positioned adjacent the guide rails 590 so that the guide structures 830 on the radio support plate 800 are aligned with the guide rails 590. The installer may then move the new radio support plate 800 laterally so that the guide structures 830 are captured by the respective guide rails 590 on the base station antenna 510. Once the new radio support plate 800 (with new beamforming radio 550 mounted thereon) is fully installed on the guide rails 590, the above-discussed stop/latching mechanism(s) may be engaged to prevent lateral movement of the new radio support plate 800 relative to the base station antenna 510. It should be noted that in some embodiments the new beamforming radio 550 may be installed without the use of any tools or with only a screwdriver.
As discussed above, conventional jumper cables 560 may be used to connect each connector port 552 on a beamforming radio 550 to a respective RF connector port 532 on the base station antenna 510. The RF connector ports 532 may be mounted, for example, on a plate 530 on the rear surface of the antenna 510 or on the bottom end cap 514 of the antenna 510, as discussed above. Any appropriate RF connectors may be used for the RF connector ports 532 such as, for example, 4.3/10 connectors. In other embodiments, blind mate connectors may be used on either the beamforming radio 550 or on the antenna to simplify electrically connecting the beamforming radios 550 to the base station antenna 510.
For example, referring to
As is further shown in
In other embodiments (not shown), the end of each jumper cable 870 that is not mounted in the connector plate 860 may have a conventional RF connector mounted thereon. In such embodiment, each jumper cable 870 may be individually connected by an installer to a respective RF connector port 532 on the base station antenna 510. In still other embodiments (also not shown), the second ends of the respective jumper cables 870 may be mounted in a second connector plate 860 and the second connector plate 860 may be pushed into place onto the RF connector ports 532 of the base station antenna 510 in order to connect all of the jumper cables 870 to the base station antenna 510 in a single operation.
It will also be appreciated that jumper cable assemblies that have cluster connectors on both ends of the cables may be used in other embodiments or alternatively be used to provide the RF connections between the beamforming radios 550 and the base station antenna 510.
Embodiments of the present invention have been described above 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. Like numbers refer to like elements throughout.
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 like fashion (i.e., “between” versus “directly between”, “adjacent” versus “directly adjacent”, etc.).
Relative terms such as “below” or “above” or “upper” or “lower” or “horizontal” or “vertical” may be used herein to describe a relationship of one element, layer or region to another element, layer or region as illustrated in the figures. It will be understood that these terms are 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” “comprising,” “includes” and/or “including” 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.
Aspects and elements of all of the embodiments disclosed above can be combined in any way and/or combination with aspects or elements of other embodiments to provide a plurality of additional embodiments.
The present application is a (voluntary) divisional application of U.S. patent application Ser. No. 17/280,960, filed Mar. 29, 2021 which is a 35 USC § 371 US national stage application of PCT/US2019/054661, filed Oct. 4, 2019, which claims priority under 35 U.S.C. § 119 to U.S. Provisional Patent Application Ser. No. 62/779,468, filed Dec. 13, 2018, and to U.S. Provisional Patent Application Ser. No. 62/741,568, filed Oct. 5, 2018, the entire content of each of which is incorporated herein by reference as if set forth in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 8743008 | Kim | Jun 2014 | B2 |
| 9888391 | Ho | Feb 2018 | B2 |
| 20050206575 | Chadwick et al. | Sep 2005 | A1 |
| 20110237299 | Boss et al. | Sep 2011 | A1 |
| 20120280874 | Kim et al. | Nov 2012 | A1 |
| 20140313095 | Pu et al. | Oct 2014 | A1 |
| 20160066476 | Gu | Mar 2016 | A1 |
| 20160099745 | Ho | Apr 2016 | A1 |
| 20160119796 | Ho | Apr 2016 | A1 |
| 20160240916 | Rucki | Aug 2016 | A1 |
| 20160365618 | Kim | Dec 2016 | A1 |
| 20170149115 | Sierzenga | May 2017 | A1 |
| 20170215192 | Lipowski et al. | Jul 2017 | A1 |
| 20170365921 | Webb et al. | Dec 2017 | A1 |
| 20190390797 | Bell et al. | Dec 2019 | A1 |
| 20210218156 | Patel et al. | Jul 2021 | A1 |
| Number | Date | Country |
|---|---|---|
| 201233948 | May 2009 | CN |
| 103490175 | Jan 2014 | CN |
| 208782034 | Apr 2019 | CN |
| 0994524 | Apr 2000 | EP |
| 3217475 | Sep 2017 | EP |
| 2015050669 | Mar 2015 | JP |
| 2013191800 | Dec 2013 | WO |
| 2016036951 | Mar 2016 | WO |
| 2016095960 | Jun 2016 | WO |
| 2018140305 | Aug 2018 | WO |
| Entry |
|---|
| International Search Report and the Written Opinion of the International Searching Authority corresponding to International Patent Application No. PCT/US2019/054661 (14 pages) (dated Feb. 14, 2020). |
| Extended European Search Report corresponding to European Patent Application No. 19869997.7 (11 pages) (dated Jun. 7, 2022). |
| Number | Date | Country | |
|---|---|---|---|
| 20210218156 A1 | Jul 2021 | US |
| Number | Date | Country | |
|---|---|---|---|
| 62779468 | Dec 2018 | US | |
| 62741568 | Oct 2018 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17280960 | US | |
| Child | 17218601 | US |
