CROSS-REFERENCE TO RELATED APPLICATIONSThe present application claims priority to
U.S. Provisional Application No. 62/980,553, filed on February 24, 2020, and is related to
U.S. Provisional Patent Application Serial No. 62/779,468, filed December 13, 2018, to
U.S. Provisional Patent Application Serial No. 62/741,568, filed October 5, 2018, and to PCT Application No.
PCT/US2019/054661, the content of each of which is incorporated by reference herein as if set forth in its entirety.
The present inventive concepts generally relate 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.
According to some aspects of the present disclosure, a base station antenna assembly may include a base station antenna having a frame and a radome that covers the frame; and a first radio mounted to a radio support plate on a rear side of the base station antenna. The radio support plate may be configured to attach to the base station antenna by at least one guide rail that cooperates with one or more guide structures of the radio support plate.
In some aspects, the guide rail may include a slot, which may in some aspects have a generally C-shaped cross-section. In some aspects, the one or more guide structures may include a rod, which may be formed of a plastic material. In some aspects, the base station antenna may include a plurality of jumper cables that communicatively couple the base station antenna with the first radio. In some aspects, the base station antenna assembly may include at least two cables that communicatively couple the base station antenna with the first radio, with the at least two cables ganged together via a ganged connector. In some aspects, a rear surface of the radome may include a plurality of access holes, and the base station antenna assembly may include a plurality of connectorized cables soldered to components within an interior of the base station antenna that extend from the interior of the base station antenna through respective ones of the access holes. In some aspects, a rear surface of the radome may include a panel in which a plurality of connector ports are mounted.
According to some aspects of the present disclosure, a base station antenna assembly may 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. A first guide rail may be mounted on one of the base station antenna and the radio support plate and a first cooperating rod may be mounted on the other of the base station antenna and the radio support plate. The first guide rail and the first corresponding rod may be configured so that when the first cooperating rods are received within a slot in the first guide rail the radio support plate is mounted on the base station antenna.
In some aspects, the base station antenna assembly may include a first locking pin, where the first guide rail comprises top and bottom walls each having a first pin through hole therein which is dimensioned to receive the first locking pin. The first corresponding rod may include first pin through holes therein which are dimensioned to receive the first locking pin. In some aspects, the base station antenna assembly may include a second locking pin, where the top and bottom walls each have a second pin through hole therein which is dimensioned to receive the second locking pin. The first corresponding rod may include second pin through holes therein which are dimensioned to receive the second locking pin. In some aspects, the first guide rail may be mounted on the base station antenna and the first corresponding rod may be mounted on the radio support plate opposite the first radio.
According to some aspects of the present disclosure, a base station antenna assembly may include a base station antenna having a frame, a radome that covers the frame, and a bottom end cap; and a first radio mounted to the frame on a rear side of the base station antenna. A rear surface of the radome may include a first opening, and a panel having a plurality of access holes may be mounted in the first opening. A plurality of connectorized cables may be soldered to components within an interior of the base station antenna and may extend from the interior of the base station antenna through respective ones of the access holes.
In some aspects, the first radio may be mounted to the frame via a first radio support plate. A first guide rail may be mounted on one of the base station antenna and the radio support plate and a first cooperating rod may be mounted on the other of the base station antenna and the radio support plate. The first guide rail and the first corresponding rod may be configured so that when the first cooperating rods are received within a slot in the first guide rail the radio support plate is mounted on the base station antenna. In some aspects, the base station antenna assembly may include first locking pin, and the first guide rail may include top and bottom walls each having a first pin through hole therein which is dimensioned to receive the first locking pin. In some aspects, the first corresponding rod may include first pin through holes therein which are dimensioned to receive the first locking pin. In some aspects, the base station antenna assembly may include a second locking pin, and the top and bottom walls may each have a second pin through hole therein which is dimensioned to receive the second locking pin.
- FIG. 1 is a perspective view of a base station antenna according to embodiments of the present inventive concepts.
- FIG. 2 is a schematic cross-sectional view of the antenna assembly with the elements mounted behind the main backplane and the sub-module backplane omitted.
- FIG. 3 is a front perspective view of a base station antenna having a large number of RF connector ports.
- FIG. 4A is a front perspective view of a base station antenna according to further embodiments of the present inventive concepts.
- FIG. 4B is a back perspective view of the base station antenna ofFIG. 4A.
- FIG. 4C is a front view of the base station antenna ofFIG. 4A.
- FIG. 4D is a back view of the base station antenna ofFIG. 4A.
- FIG. 5A is a back view of the base station antenna ofFIGS. 4A-4D with a pair of active radios mounted thereon to provide an antenna assembly.
- FIG. 5B is a side view of the antenna assembly ofFIG. 5A.
- FIG. 5C is a back perspective view of the antenna assembly ofFIG. 5A.
- FIG. 5D is a partial back perspective view of the antenna assembly ofFIG. 5A with the radome removed.
- FIG. 6 is an end view of an antenna assembly that includes a base station antenna and a beamforming radio.
- FIG. 7 is an end view of an antenna assembly that includes a base station antenna and a beamforming radio.
- FIG. 8A is a rear perspective view of a base station antenna illustrating how guide rails may be mounted thereon that are used to mount beamforming radios on the back of the antenna.
- FIG. 8B is a rear perspective view of a base station antenna ofFIG. 8A illustrating how radio support plates may be mounted on the antenna using the guide rails.
- FIG. 8C is an perspective view illustrating how guide structures on the radio support plate may be received within one of the guide rails mounted on the antenna.
- FIG. 8D is an enlarged view of a portion ofFIG. 8C showing how the radio support plates may be locked in place after the radio support plates are mounted on the base station antenna.
- FIG. 8E is an enlarged partial view illustrating the jumper cables that connect the beamforming radio to the base station antenna.
- FIGS. 9A-9C are schematic back views illustrating alternative arrangements for the connector port arrays included in the base station antenna ofFIGS. 4A-4D.
DETAILED DESCRIPTIONEmbodiments of the present inventive concepts will now be described in further detail with reference to the attached figures.
FIGS. 1and2 illustrate abase station antenna100 according to certain embodiments of the present inventive concepts. In the description that follows, theantenna100 will be described using terms that assume that theantenna100 is mounted for use on a tower with the longitudinal axis L of theantenna100 extending along a vertical axis and the front surface of theantenna100 mounted opposite the tower pointing toward the coverage area for theantenna100.
Referring first toFIG. 1, thebase station antenna100 is an elongated structure that extends along a longitudinal axis L. Thebase station antenna100 may have a tubular shape with generally rectangular cross-section. Theantenna100 includes aradome110 and atop end cap120. Theradome110 and thetop end cap120 may comprise a single integral unit, which may be helpful for waterproofing theantenna100. One or more mounting brackets (not shown) may be provided on the rear side of theantenna100 which may be used to mount theantenna100 onto an antenna mount (not shown) on, for example, an antenna tower. Theantenna100 also includes abottom end cap130 which includes a plurality ofconnectors140 mounted therein. Theantenna100 is typically mounted in a vertical configuration (i.e., the longitudinal axis L may be generally perpendicular to a plane defined by the horizon) when theantenna100 is mounted for normal operation. Theradome110,top cap120 andbottom cap130 may form an external housing for theantenna100. An antenna assembly (not shown inFIG. 1) may be contained within the housing. The antenna assembly may be slidably inserted into theradome110, typically from the bottom before thebottom cap130 is attached to theradome110.
Briefly, as seen in the cross-sectional view ofFIG. 2, theantenna assembly200 may include amain backplane210 that has sidewalls212 and amain reflector214. Thebackplane210 may serve as both a structural component for theantenna assembly200 and as a ground plane and reflector for the radiating elements mounted thereon. Thebackplane210 may also include brackets or other support structures (not shown) that extend between thesidewalls212 along the rear of thebackplane210. InFIG. 2, various mechanical and electronic components of theantenna100 that are mounted in thechamber215 defined between thesidewalls212 and the back side of themain reflector214, such as phase shifters, remote electronic tilt units, mechanical linkages, controllers, diplexers, and the like, are omitted to simplify the drawing, and the cross-section of theradome110 is included inFIG. 3 to provide context.
Themain reflector214 may comprise a generally flat metallic surface that extends in the longitudinal direction L of theantenna100. Some of the radiating elements (discussed below) of theantenna100 may be mounted to extend forwardly from themain reflector214, 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 themain reflector214. Themain reflector214 may serve as a reflector and as a ground plane for the radiating elements of theantenna100 that are mounted thereon.
As shown inFIG. 2, theantenna100 may include a plurality of dual-polarized radiatingelements222, 232, 252. The radiating elements include low-band radiating elements222,mid-band radiating elements232, and high-band radiating elements252. The low-band radiating elements222 may be mounted to extend upwardly from themain reflector214 and, in some embodiments, may be mounted in two columns to form two linear arrays of low-band radiating elements222. Each low-band linear array may extend along substantially the full length of theantenna100 in some embodiments. The low-band radiating elements222 may be configured to transmit and receive signals in a first frequency band. In some embodiments, the first frequency band may comprise 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.).
Themid-band radiating elements232 may likewise be mounted to extend upwardly from themain reflector214 and may be mounted in two columns to form two linear arrays of firstmid-band radiating elements232. The linear arrays ofmid-band radiating elements232 may extend along the respective side edges of themain reflector214. Themid-band radiating elements232 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.).
The high-band radiating elements252 may be mounted in four columns in a portion of theantenna100 to form four linear arrays of high-band radiating elements252. The high-band radiating elements252 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 inFIG. 2. For example, the number of linear arrays of each type of radiating elements may be varied from what is shown, some types of linear arrays may be omitted and/or other types of arrays may be added, the number of radiating elements per array may be varied from what is shown, and/or the arrays may be arranged differently.
In the depicted embodiment, the low-band andmid-band radiating elements222, 232 may each be mounted to extend forwardly from themain reflector214. The high-band radiating elements252 may each be mounted to extend forwardly from a sub-module reflector, as will be described in further detail below.
Each linear array of low-band radiating elements222 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, eacharray232 of firstmid-band radiating elements232 and eacharray252 of high-band radiating elements252 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 may be configured to provide service to a sector of a base station.
Some or all of the radiatingelements222, 232, 252 may be mounted on feed boards (not shown) that couple RF signals to and from theindividual radiating elements222, 232, 252. One, or more than one, radiatingelements222, 232, 242, 252 may be mounted on each feed board. Cables (not shown) may be used to connect each feed board to other components of theantenna100 such as diplexers, phase shifters, calibration boards or the like.
In some embodiments, the base station antennas according to embodiments of the present inventive concepts may be reconfigurable antennas that include one or more self-contained sub-modules. Thebase station antenna100 includes onesuch sub-module300, which may be may be slidably received on themain backplane210. In some embodiments, themain reflector214 may have an opening (not shown) and the sub-module300 may be received in the general area of this opening when theantenna100 is fully assembled. However, it will be appreciated that embodiments of the present inventive concepts are not limited thereto, and that one or more smaller openings may be used in other embodiments, or the opening may be omitted entirely.
The sub-module
300 may include a
sub-module backplane310. The
sub-module backplane310 may include
sidewalls312 and a
sub-module reflector314. The four linear arrays of high-
band radiating elements252 may be mounted to extend forwardly from the
sub-module reflector314. As can best be seen in
FIG. 2, the
sub-module reflector314 may be mounted forwardly of the
main reflector214. This may advantageously position the high-
band radiating elements252 closer to the
radome110 so that the
radome110 is within the near field of the high-
band radiating elements252. Greater detail concerning the sub-module is provided in PCT Application No.
PCT/US2019/054661, which has already been incorporated by reference.
Theantenna assembly100 ofFIGS. 1 and2 may have a number of advantages over conventional antennas. As cellular operators upgrade their networks to support fifth generation ("5G") service, the base station antennas that are being deployed are becoming increasingly complex. For example, due to space constraints and/or allowable antenna counts on antenna towers of existing base stations, it may not be possible to simply add new antennas to support 5G service. Accordingly, cellular operators are opting to deploy antennas that support multiple generations of cellular service by including linear arrays of radiating elements that operate in a variety of different frequency bands in a single antenna. Thus, for example, it is common now for cellular operators to request a single base station antenna that supports service in three, four or even five or more different frequency bands. Moreover, in order to support 5G service, these antennas may include multi-column arrays of radiating elements that support active beamforming. Cellular operators are seeking to support all of these services in base station antennas that are comparable in size to conventional base station antennas that supported far fewer frequency bands. This raises a number of challenges.
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, theantenna assembly100 that is described with reference toFIG. 1 and2 may include two linear arrays of low-band radiating elements222, two linear arrays of firstmid-band radiating elements232, and a four column planar array of high-band radiating elements252. All of the radiatingelements222, 232, 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 thebase station antenna200 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 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, as seen inFIG. 1 at130. 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, inFIG. 3, which is a perspective view of a base station antenna having a large number ofRF connector ports532. When theRF connector ports532 are close together as is the case in the antenna illustrated inFIG. 3, it may be difficult for technicians to install (and properly tighten) coaxial jumper cables onto theRF connector ports532. If a jumper cable is not properly installed onto its correspondingRF connector port532, various problems including passive intermodulation distortion or even loss of the RF connection may occur, requiring expensive and time-consuming tower climbs to correct the situation. In addition, as the density ofRF connector ports532 is increased, so is the possibility that a technician will connect one or more of the jumper cables to the wrongRF connector ports532, again requiring tower climbs to correct. This problem may be exacerbated by the fact that the denser the array ofRF connector ports532 the less room there is on the bottom end cap for labels that assist the technician in the installation process.
Pursuant to embodiments of the present inventive concepts, 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 toFIGS. 4.
Turning first toFIGS. 4A-4D, abase station antenna510 is depicted that is designed so that a pair of cellular radios may be mounted on the back side of the housing thereof. In particular,FIGS. 4A and4B are a front perspective view and a rear perspective view, respectively, of thebase station antenna510, whileFIGS. 4C and4D are a front view and a rear view, respectively, of thebase station antenna510.
As shown inFIG. 4A-4D, thebase station antenna510 includes atop end cap512, abottom end cap514 and aradome520. Aback surface522 of theradome520 includes a pair of openings. Aconnector plate530 is mounted in each opening, and a plurality ofRF connector ports532 that form an array534 ofconnector ports532 are mounted in eachconnector plate530. In the depicted embodiment, eachconnector plate530 has a total of nineconnector ports532 mounted therein. Eachconnector port532 may comprise an RF connector port that may be connected to an RF port on a radio by a suitable connectorized cable such as, for example, a coaxial jumper cable. In one example embodiment, eachRF connector port532 may comprise a double-sided connector port so that respective coaxial jumper cables may be connected to each side of eachRF connector port532. Accordingly, first coaxial jumper cables (not shown) that are external to theantenna510 may extend between eachRF connector port532 and a respective RF connector port on a radio (not shown) that is mounted on the back of theantenna510, and second coaxial jumper cables (not shown) that are internal to theantenna510 may extend between eachRF connector port532 and one or more internal components of theantenna510.
FIGS. 5A-5D are various views that illustrate thebase station antenna510 ofFIGS. 4A-4D after twobeamforming radios550 have been mounted on the back side of the antenna to provide anantenna assembly500. In particular,FIG. 5A is a back view of theantenna assembly500,FIG. 5B is a side view of theantenna assembly500,FIG. 5C is a back perspective view of theantenna assembly500, andFIG. 5D is a partial back perspective view of theantenna assembly500 with theradome520 removed.
Referring toFIGS. 5A-5D, it can be seen that theantenna assembly500 includes thebase station antenna510 ofFIGS. 4A-4D and a pair ofcellular radios550 that are mounted on the back surface of theradome520. Ninecoaxial jumper cables560 extend between nine connector ports552 that are provided on eachradio550 and the nineconnector ports532 provided on a corresponding one of theconnector plates530.
As discussed above, in theantenna assembly500 according to embodiments of the present inventive concepts, two arrays534 ofRF connector ports532 are provided on the back surface of thebase station antenna510. One of the arrays534 ofconnector ports532 may comprise theRF connector ports532 for the four column planar array240 of second mid-band radiating elements242 and the other array534 ofRF connector ports532 may comprise theRF connector ports532 for the four column planar array250 of high-band radiating elements252. As shown inFIGS. 5A-5D, this allows the RF connector ports552 on each of thebeamforming radios550 to be connected to their correspondingRF connector ports532 on thebase station antenna510 by very shortcoaxial jumper cables560. This may result in as much as a 2-3 dB improvement in RF cable losses, which may provide a significant increase in throughput.
Additionally, by mounting thebeamforming radios550 directly onto thebase station antenna510, the cellular operator may avoid leasing tower costs for the tworadios550, as leasing costs are typically based on the number of elements that are separately mounted on an antenna tower. Additionally, by moving eighteen of theRF connector ports532 to the back of theantenna510, the number ofRF connector ports532 mounted on thebottom end cap514 may be reduced significantly (e.g., to eight RF connector ports in the example set forth above). This may make it easier for technicians to properly install thejumper cables560, and leaves plenty of room for easy to read labels that aid installation.
Moreover, in some embodiments, thebase station antenna510 may be designed so thatradios550 manufactured by a wide variety of different equipment manufacturers may be mounted thereon. For example, the frame of the base station antenna510 (which is located inside the radome520) may include rails or other vertically extending members along the back surface thereof that theradios550 may be mounted on. This may allow a cellular operator to order abase station antenna510 according to embodiments of the present inventive concepts from a first vendor, afirst beamforming radio550 from a second vendor and asecond beamforming radio550 from a third vendor and then combine the three together to form theantenna assembly500. This provides significant flexibility to the cellular operator to select vendors and/or equipment that best suit the needs of the cellular operator.
WhileFIGS. 4A-5D illustrate embodiments in which theRF connector ports532 for bothbeamforming radios550 are mounted on connector plates on the rear surface of basestation antenna assemblies500 and500A-500C, it will be appreciated that embodiments of the inventive concepts are not limited thereto. For example, any of these embodiments may be modified so that theRF connector ports532 for at least one of the twobeamforming radios550 are mounted on thebottom end cap514 of thebase station antenna510.
One example of such a
base station assembly500A in which the
RF connector ports532 for at least one
beamforming radios550 are mounted on the
bottom end cap514 of the
base station antenna510 is illustrated in
FIG. 6. As is further shown in
FIG. 6, while a first end of each jumper cable
870 may be received at a respective connector of the
beamforming radio550, the second end of each jumper cable
870 may be connected to one or more cluster connectors
880. A cluster connector may comprise a plurality of connectors that are fixedly premounted in a common plate. In the embodiment shown in
FIG. 6, two cluster connectors
880-1, 880-2 are provided, with five of the jumper cables
870 connected to the first cluster connector
880-1 and the remaining four jumper cables
870 connected to the second cluster connector
880-2. The
RF ports532 on
base station antenna510 may be arranged to mate with the two cluster connectors
880, and each cluster connector
880 may be pushed onto a corresponding group of four or five
RF connector ports532 in order to quickly and easily connect the jumper cables
870 to the
base station antenna510. Suitable cluster connectors are disclosed in
U.S. Patent Application Serial No. 16/375,530, filed April 4, 2019, the entire content of which is incorporated herein by reference. 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 radios550 and the
base station antenna510.The antenna assemblies according to embodiments of the present inventive concepts, such asantenna assemblies500 and500A, may also be designed so that theradios550 may be field-replaceable. Herein, a field-replaceable radio refers to aradio550 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. As is seen inFIG. 6, mountingbrackets570 that attach between theantenna assembly500 and the antenna tower (or other mounting structure) may connect to thebase station antenna510 as opposed to connecting to theradios550. Additionally, as shown inFIG. 6, the mountingbrackets570 may be spaced apart from theradios550 so that a technician can access and remove theradios550 while theantenna510 is mounted on the antenna tower. In some embodiments, cable guides872 may be provided within the mountingbrackets570. The cable guides872 may retain the jumper cables870, for example during replacement or repair of theradio550.
The various embodiments of theantenna assembly500 illustrated with respect toFIGS. 4A-6 useexternal jumper cables560/870 to connect the RF connector ports552 on thebeamforming radios550 to theRF connector ports532 that are mounted on the back surface of theradome520 or thebottom end cap514. Theexternal jumper cables560/870 have connectors on each end, which may be of the same type or of different types. The present disclosure is not limited to the use of such jumper cables, however. Pursuant to some embodiments of the present inventive concepts, theRF connectors532 included in theantenna assembly500 may be replaced with access holes.
FIG. 7 is a back view of anantenna assembly700 that includes such a design. As shown inFIG. 7, theantenna assembly700 includes abase station antenna710 that at least onebeamforming radio750 mounted on a rear surface thereof. Theradome720 ofantenna710 includes at least onepanel730 that hasaccess openings732 therein. Each access opening732 may be surrounded by a gland or seal to provide weatherproofing.Pigtail cables760 may be factory-coupled (e.g., soldered) to internal components within thebase station antenna710 and may extend from through acorresponding access hole732 to connect with a respectiveRF connector port752 on theradio750. As used herein, the term "pigtail cables" includes a cable with a connector on one end that may be factory-coupled to a component within thebase station antenna710, and may not be field-replaceable.
Pursuant to still further embodiments of the present inventive concepts, 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. Referring toFIG. 8A, in some embodiments, one ormore guide rails590 may be mounted on the rear surface of thebase station antenna510. For example, the frame of thebase station antenna510 may have support brackets (not shown) that extend between rearwardly-extending sidewalls of the frame, and eachguide rail590 may be mounted through theradome520 onto one of the support brackets using screws or other attachment mechanisms. In the embodiment shown inFIG.8A, a pair of horizontally-orientedguide rails590 is provided for eachbeamforming radio550.
As shown inFIG. 8A, eachguide rail590 may be implemented using a channel iron that has afront plate591, rearwardly extending top andbottom walls592, andlips593 that extend downwardly and upwardly from the respective top andbottom walls592 so that theguide rail590 has a generally C-shaped transverse cross-section that defines aninterior slot594. Mountingholes595 may be provided through thefront wall591 that receive screws orother fasteners596 that are used to mount eachguide rail590 on the support plate or other structural component (not shown) ofbase station antenna510. The guide rails590 may be formed of aluminum or steel in example embodiments.
As shown inFIG. 8B,radio support plates800 may be provided that are configured for mounting on the guide rails590. Eachradio support plate800 may comprise, for example, a substantially planar metal plate that has mountingholes810 therein. Theradio support plates800 need not be planar, however, and may include, for example, rearwardly-extendinglips820 or other non-planar features (e.g., theplate radio support800 may be a corrugated plate). The size of eachradio support plate800 and the location of the mountingholes810 may be customized based on the design of thebeamforming radio550 that is to be mounted on thebase station antenna510. Thus, differentradio support plates800 may be provided for different beamforming radio manufacturers and/or fordifferent beamforming radio550 models. For example, thebeamforming radios550 may include top and bottom mounting flanges (not shown) that have openings therein. The openings may be aligned with the mountingholes810 on theradio support plates800 so that eachbeamforming radio550 may be mounted on a respectiveradio support plate800 using screws, bolts or other fasteners.
FIG. 8C is a perspective view of the rear of thebase station antenna510. Referring toFIG. 8C, one or more guide structures830 may be mounted on the surface of theradio support plate800 that is configured to face thebase station antenna110. The guide structures may be mounted using, for example, screws or bolts. In the depicted embodiment, each guide structure830 comprises arod840. Theradio support plate800 and thebeamforming radio550 are not shown inFIGS. 8C and8D to better describe aspects of therod840 and the guide rails590.
Therod840 is sized to be received in theslot594 that is defined between thefront plate591, top andbottom walls592 andlips593 of one of the guide rails590. Accordingly, aradio support plate800 having guide structures830 in the form of therod840 may be mounted on one ormore guide rails590 by sliding theradio support plate800 laterally parallel to the guide rail(s)590 so that therod840 is received within theslots594 in the guide rail(s)590. As best seen inFIG. 8D, which is an enlarged view of a portion ofFIG. 8C, pin throughholes597 may be provided in the top andbottom walls592 at each end of the guide rails590. The pin throughholes597 may be dimensioned to receive alocking pin598. In some embodiments, therod840 may have corresponding through holes841 that are positioned along a length of therod840 such that, when therod840 is slid into position within theslot594, the corresponding through holes841 of therod840 align with the pin throughholes597 of the top andbottom walls592. As such, the lockingpin598 may be received through both theguide rail590 and therod840.
Alternatively, therod840 may be dimensioned to be slightly shorter in length than theguide rail594, and the corresponding through holes may be omitted from therod840. During installation, afirst locking pin598 at a first end of theguide rail590 may be inserted through the pin throughholes597 in both the top andbottom walls592 at the first end of theguide rail594. Theradio support plate800 may be mounted onto thebase station antenna510 by sliding therod840 into theslot594 from the second end of theguide rail590 until therod840 abuts the locking pin. Once theradio support plate800 is in place, asecond locking pin598 may be inserted through the pin throughholes597 at the second end of theguide rail590. Once therods840 on theradio support plate800 have been fully inserted into therespective slots594 of theguide rails590, and the first and second locking pins598 have been inserted in the pin throughholes597 at each end of theguide rails590, lateral movement of the radio support plate800 (and theradio550 mounted thereon) relative to thebase station antenna510 is hindered and/or effectively prevented.
In some embodiments, machining tolerances of theguide rails590 and/or therods840 of the radio support plate may result in a thickness of the rod being less than a distance from thefront plate591 to the inner surface of thelips593 of the guide rail. Moreover, even where machining tolerances are controlled, the thickness of therod840 may be less than the corresponding dimension of theslot840 so as to permit relatively easy sliding of therods840 relative to the guide rails590. Although lateral movement is prevented by the locking mechanisms, the thickness of therod840 relative to theguide rail590 may create a potential for slight movement of theradio support plate800 toward and away from thebase station antenna510. This movement, which may be exacerbated by wind loads at the installation site, may result in degradation of either internal components of thebeamforming radio550 and or the connectors electrically connecting thebeamforming radio550 with thebase station antenna510. To prevent such movement, a locking mechanism860 may be provided. As shown, the locking mechanism860 may include an offsetcam861 that is rotatable into position vialever862. After sliding of therods840 of theradio support plate800 into theguide rails590, thelever862 may be rotated, causing the offsetcam861 to pressrod840 into contact with thefront plate591 of theguide rail590. Such contact, which is maintained by the offsetcam861, hinders and/or effective prevents the movement of theradio support plate800 relative to thebase station antenna510.
In some aspects, therod840 may be formed of a plastic or other material selected to reduce or prevent the formation of passive intermodulation interference (PIM) products. PIM is a form of electrical interference that may occur when two or more RF signals encounter non-linear electrical junctions or materials along an RF transmission path. Such non-linearities may act like a mixer causing the RF signals to generate new RF signals at mathematical combinations of the original RF signals. PIM may result from inconsistent metal-to-metal contacts along an RF transmission path and/or the RF reception path, particularly when such inconsistent contacts are in high current density regions of the paths such as inside RF transmission lines, inside RF components, or on current carrying surfaces of an antenna. Such inconsistent metal-to-metal contacts may occur, for example, because of contaminated and/or oxidized signal carrying surfaces, loose connections between two connectors, metal flakes or shavings inside RF components or connections and/or poorly prepared soldered connections (e.g., a poor solder termination of a coaxial cable onto a printed circuit board). Other PIM may result from a metallic surface located within the transmission range of the antenna, such as a tower or mounting structure on which the antenna is mounted, or stationary or moving structures or objects nearby. The non-linearities that give rise to PIM may be introduced at the time of manufacture, during installation, or due to electro-mechanical shift over time due to, for example, mechanical stress, vibration, thermal cycling, and/or material degradation. As such, embodiments of the present inventive concepts include those in which therod840 and/or other components of theradio support plate 800 orguide rail590 are formed from non-metallic materials.
It will be appreciated that a wide variety of other guide structures could be used. It will also be appreciated that in still further embodiments the guide structures may be mounted on the rear surface of thebase station antenna510 and theguide rails590 may be mounted on theradio support plate800.
Referring toFIG. 8E,jumper cables560 may then be installed that electrically connect the connector ports552 on eachbeamforming radio550 to respectiveRF connector ports532 on thebase station antenna510, though the arrangement ofFIGS.8A-8E may be used with any cabling between thebeamforming radio550 and thebase station antenna510, including those illustrated inFIGS. 6 and7.
According to the present disclosure, thebeamforming radios550 may 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. Thebeamforming radios550 of basestation antenna assembly500 may be field replaceable without the need to detach thebase station antenna510 from an antenna mount. Instead, thejumper cables560 that extend between thebase station antenna510 and thebeamforming radios550 may be removed, and any stop mechanisms such as stop bolts or latches that are used to hold eachradio support plate800 with abeamforming radio550 mounted thereon in place (to prevent lateral movement of theradio support plate800 relative to the radio550) on thebase station antenna510 may also be removed or unlatched. Eachradio support plate800 with abeamforming radio550 mounted thereon may then be removed simply by sliding theradio support plate800 laterally until the guide structure(s)830 are free of theslots594 in the respective guide rails590. Then, adifferent beamforming radio550 that is mounted on an appropriateradio support plate800 may be positioned adjacent theguide rails590 so that the guide structures830 on theradio support plate800 are aligned with the guide rails590. The installer may then move the newradio support plate800 laterally so that the guide structures830 are captured by therespective guide rails590 on thebase station antenna510. Once the new radio support plate800 (withnew beamforming radio550 mounted thereon) is fully installed on theguide rails590, the above-discussed stop/latching mechanism(s) may be engaged to prevent lateral movement of the newradio support plate800 relative to thebase station antenna510. It should be noted that in some embodiments thenew beamforming radio550 may be installed without the use of any tools or with only a screwdriver.
In some of the example embodiments provided herein, thebase station antenna510 is configured so that the first array534-1 ofRF connector ports532 is mounted near the bottom of the back surface of theradome520, and the second array534-2 ofRF connector ports532 is mounted near the middle of the back surface of theradome520. Thebeamforming radios550 are mounted above their corresponding arrays534 ofRF connector ports532 in this design. It will be appreciated, however, that embodiments of the present inventive concepts are not limited to this configuration. For example,FIGS. 9A-9C are schematic back views illustrating alternative arrangements for the arrays534 ofRF connector ports532 that may be employed in base station antennas according to further embodiments of the present inventive concepts.
As shown inFIG. 9A, in a first alternative embodiment, anantenna assembly500B is provided in which the first array534-1 ofRF connector ports532 may be mounted near the top of the back surface of theantenna510, and the second array534-2 ofRF connector ports532 may be mounted near the middle of the back surface of theantenna510. In this embodiment, thebeamforming radios550 may be mounted below their corresponding arrays534 ofRF connector ports532. As shown inFIG. 9B, in a second alternative embodiment, anantenna assembly500C is provided in which the first and second arrays534-1, 534-2 ofRF connector ports532 may each be mounted near the middle of the back surface of theantenna510, with onebeamforming radio550 mounted above the arrays534 ofRF connector ports532 and theother beamforming radio550 mounted below the arrays534 ofRF connector ports532. As shown inFIG. 9C, in a third alternative embodiment, anantenna assembly500D is provided in which the first array534-1 ofRF connector ports532 may be mounted near the top of the back surface of theantenna510, and the second array534 ofRF connector ports532 may be mounted near the bottom of the back surface of theantenna510, and the twobeamforming radios550 may be mounted in between the two arrays534 ofRF connector ports532.
It will be appreciated that many modifications may be made to the antenna assemblies described above without departing from the scope of the present inventive concepts. For example, while some of 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 inventive concepts 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, 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.
Embodiments of the present inventive concepts have been described above with reference to the accompanying drawings, in which embodiments of the inventive concepts are shown. The inventive concepts 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 inventive concepts 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 inventive concepts. 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 inventive concepts. 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.
Particularly preferred aspects of this case are given in the following:
- 1. A base station antenna assembly, comprising: a base station antenna having a frame and a radome that covers the frame; a first radio mounted to a radio support plate on a rear side of the base station antenna; wherein the radio support plate is configured to attach to the base station antenna by at least one guide rail that cooperates with one or more guide structures of the radio support plate.
- 2. The base station antenna assembly of aspect 1, wherein the guide rail includes a slot.
- 3. The base station antenna assembly of the preceding aspects, in particular aspect 2, wherein the slot has a generally C-shaped cross-section.
- 4. The base station antenna assembly of any of the preceding aspects, in particular aspect 3, wherein the one or more guide structures comprises a rod.
- 5. The base station antenna assembly of any of the preceding aspects, in particular aspect 4, wherein the rod comprises a plastic material.
- 6. The base station antenna assembly of any of the preceding aspects, in particular aspects 1-5, further comprising a plurality of jumper cables that communicatively couple the base station antenna with the first radio.
- 7. The base station antenna assembly of any of the preceding aspects, in particular aspects 1-5, further comprising at least two cables that communicatively couple the base station antenna with the first radio, wherein the at least two cables are ganged together via a ganged connector.
- 8. The base station antenna assembly of any of the preceding aspects, in particular aspects 1-5, wherein a rear surface of the radome includes a plurality of access holes, and wherein the base station antenna assembly comprises a plurality of connectorized cables soldered to components within an interior of the base station antenna that extend from the interior of the base station antenna through respective ones of the access holes.
- 9. The base station antenna assembly of any of the preceding aspects, in particular aspects 1-5, wherein a rear surface of the radome includes a panel in which a plurality of connector ports are mounted.
- 10. A base station antenna assembly, comprising: a base station antenna having a frame and a radome that covers the frame; and a first radio mounted on a radio support plate;
wherein a first guide rail is mounted on one of the base station antenna and the radio support plate and a first cooperating rod is mounted on the other of the base station antenna and the radio support plate, wherein the first guide rail and the first corresponding rod are configured so that when the first cooperating rods are received within a slot in the first guide rail the radio support plate is mounted on the base station antenna. - 11. The base station antenna assembly of any of the preceding aspects, in particular aspect 10, further comprising a first locking pin, wherein the first guide rail comprises top and bottom walls each having a first pin through hole therein which is dimensioned to receive the first locking pin.
- 12. The base station antenna assembly of any of the preceding aspects, in particular aspect 11, wherein the first corresponding rod comprises first pin through holes therein which are dimensioned to receive the first locking pin.
- 13. The base station antenna assembly of any of the preceding aspects, in particular aspect 11 or aspect 12, further comprising a second locking pin, wherein the top and bottom walls each have a second pin through hole therein which is dimensioned to receive the second locking pin.
- 14. The base station antenna assembly of any of the preceding aspects, in particular aspect 13, wherein the first corresponding rod comprises second pin through holes therein which are dimensioned to receive the second locking pin.
- 15. The base station antenna assembly of any of the preceding aspects, in particular aspects 10-14, wherein the first guide rail is mounted on the base station antenna and the first corresponding rod is mounted on the radio support plate opposite the first radio.
- 16. A base station antenna assembly, comprising: a base station antenna having a frame, a radome that covers the frame, and a bottom end cap; and a first radio mounted to the frame on a rear side of the base station antenna; wherein 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 soldered to components within an interior of the base station antenna extend from the interior of the base station antenna through respective ones of the access holes.
- 17. The base station antenna assembly of any of the preceding aspects, in particular aspect 16, wherein the first radio is mounted to the frame via a first radio support plate, wherein a first guide rail is mounted on one of the base station antenna and the radio support plate and a first cooperating rod is mounted on the other of the base station antenna and the radio support plate, wherein the first guide rail and the first corresponding rod are configured so that when the first cooperating rods are received within a slot in the first guide rail the radio support plate is mounted on the base station antenna.
- 18. The base station antenna assembly of any of the preceding aspects, in particular aspect 17, further comprising a first locking pin, wherein the first guide rail comprises top and bottom walls each having a first pin through hole therein which is dimensioned to receive the first locking pin.
- 19. The base station antenna assembly of any of the preceding aspects, in particular aspect 18, wherein the first corresponding rod comprises first pin through holes therein which are dimensioned to receive the first locking pin.
- 20. The base station antenna assembly of any of the preceding aspects, in particular aspect 18 or aspect 19, further comprising a second locking pin, wherein the top and bottom walls each have a second pin through hole therein which is dimensioned to receive the second locking pin.
