Patent Application
20210313666
The present disclosure is broadly directed to antenna housings utilized with wireless access points that provide coverage for local service areas. More specifically, the present disclosure is directed to antenna housings having multiple individual cooling paths.
In wireless communication networks, high-powered base stations (e.g., towers supporting antennas) commonly provide service over large geographic areas. Each base station is capable of serving wireless user devices in a coverage area that is primarily determined by the power of the signals that supported antennas can transmit. Frequently, high-powered base stations (e.g., macro stations) are located in a grid pattern with each base station mounting various antennas elevated on a tower. While such towers have previously provided adequate coverage for many wireless applications, such high-powered base stations tend to be too widely spaced for newer high-bandwidth wireless applications.
To improve wireless access, providers are moving toward smaller stations that provide enhanced coverage for more limited geographic areas. That is, to augment the coverage of the wireless network, wireless transceiver devices/antennas (e.g., access points) with relatively small coverage areas (and serving capacities) are deployed. Depending on their coverage area and serving capacities, these wireless transceiver devices are referred to as “femto” cells or “pico” cells. For simplicity and generality, the term “small cell pole” is used herein to refer to a wireless transceiver access point that is configured to serve wireless user devices over relatively small coverage areas as compared to a high-powered base station that is configured to serve a relatively large coverage area (“macro cell”).
The increasing use of RF bandwidth or ‘mobile data’ has required a corresponding increase in the number of access points to handle the increased data. By way of example, 5G wireless networks providing improved network speeds are currently being planned and implemented. Such networks typically require shorter RF transmission distances compared to existing networks and thereby require more dense networks of access points. Along these lines, access points are, in some instances, being installed in urban areas to serve several city blocks or even to serve a single city block. Such installations are often below roof-top level of surrounding buildings. That is, access points are being installed at ‘steel-level’ sites typically on small dedicated small cell poles as well as on existing utility poles (e.g., streetlights, stoplights, etc.). The increasing number of access points is sometimes referred to as densification of wireless infrastructure. Residents often object to such densification in their neighborhoods due to the aesthetic concerns of wireless antennas supported by various dedicated and/or existing utility poles. To help alleviate aesthetic concerns, wireless provider commonly conceal antennas supported by such poles within a shrouding or antenna housing. Antenna housings having a minimal form factor necessary to house an antenna are typically preferred to minimize to overall obtrusiveness of a set of antennas supported by a pole.
The present disclosure is directed to antenna housings utilized to house individual antennas. Such an individual antenna and individual housing may be considered a modular antenna unit. When modular antenna units are utilized, an access point will typically have three units disposed about a support pole to provide coverage for three 120 degree sectors. Variation is possible. Aspects of the present disclosure are based on the realization that the ever increasing antenna power to enhance coverage and/or data transfer in conjunction with efforts to minimize the size (e.g., small form factor) of antenna housings to address aesthetic concerns can result in thermal management concerns for modular antenna units. That is, the small form factor housing may not provide adequate ventilation to allow effectively cooling an antenna disposed within the housing. In this regard, heat generated by operation of the antenna is at least partially contained within the housing, which can result in the antenna operating in a thermal environment above recommended operation temperatures. Accordingly, the present disclosure is directed to a modular antenna housing that provides multiple ducting paths through the housing to provide better cooling and thereby reduce temperatures within an interior of the antenna housing.
In one implementation, an antenna housing is provided. The antenna housing is primarily configured to be mounted to a pole. The antenna housing may be a modular housing configured to hold a single antenna. Typically, such an antenna(s) is at least partially disposed within the interior of the antenna housing such that it is partially concealed. That is, the antenna(s) is at least partially enclosed within a sidewall and/or shrouding of the housing. When housing an antenna, an active or emitting surface of the antenna is typically directed outward from the interior of the housing. In some arrangements, an emitting surface may be exposed through an aperture in the sidewall and/or shrouding.
In order to provide cooling to an internal cooling duct of an antenna is disposed within the housing, the housing may further include an inlet duct and an outlet duct. These ducts extend through a sidewall of the housing. These ducts allow air to be drawn into the housing, pass through the internal cooling duct of the antenna unit and be exhausted from the housing. The inlet, cooling and outlet duct provide a closed (e.g., substantially sealed) airflow path into and out of the housing. Additionally, spaces between outside surfaces or the antenna unit and inside surfaces of the housing provide additional air flow paths (e.g., between various vents in the housing) around the antenna unit. These additional flow paths may be at least partially isolated from one another and provide. Further, the additional flow paths may provide an effective means for removing heat caused by solar irradiation from the housing.
Reference will now be made to the accompanying drawings, which at least assist in illustrating the various pertinent features of the presented inventions. The following description is presented for purposes of illustration and description and is not intended to limit the inventions to the forms disclosed herein. Consequently, variations and modifications commensurate with the following teachings, and skill and knowledge of the relevant art, are within the scope of the presented inventions. The embodiments described herein are further intended to explain the best modes known of practicing the inventions and to enable others skilled in the art to utilize the inventions in such, or other embodiments and with various modifications required by the particular application(s) or use(s) of the presented inventions.
The present disclosure is broadly directed to wireless antenna housings that are primarily intended to house individual wireless antennas. Such a combined housing and antenna may be referred to as a modular antenna unit. In various embodiments, the antenna housings are configured to at least partially conceal a wireless antenna within an enclosed interior of the housing to minimize the aesthetic obtrusiveness of the modular antenna unit. Various embodiments of the present disclosure are related to the recognition by the inventors that the use of increasingly more powerful wireless antennas in modular antenna units can result in thermal concerns. That is, when an antenna is at least partially concealed within an enclosed interior of an antenna housing, heat generated during operation of the antenna tends to build up within the housing. Additionally, it has been recognized that in many geographical locations, heating from exposure to the sun can significantly increase the overall heat load within the housing. This may be exacerbated when the antenna units are elevated, which commonly results in the antenna units being fully exposed to the sun. The combination of heat generated by the antenna and solar loading can result in the enclosed antenna operating in a thermal environment above recommended operation temperatures. Accordingly, the present disclosure is directed to an antenna housing that provides multiple cooling paths through the housing to regulate temperatures within the housing.
As previously noted, wireless providers continue to increase the power of the antennas utilized for local coverage. By way of example, previous generations of antennas (e.g., 4G antennas) often had operational powers of around 150 watts. A thermal load of an antenna enclosed within a housing could be managed by providing vents at or near the bottom of the housing and vents at or near the top of the housing. Such vents permitted removal of heat from the housing via natural or forced convention. However, newer antennas (e.g., 5G antennas) having higher operational power (e.g., 400-500 watts) may produce more heat than can be removed utilizing such simplified venting. When such an antenna is enclosed within a housing, heat generated during operation tends to build up. This is further complicated in applications where antenna housings are subject to direct sunlight. Specifically, heat from sunlight incident on front, sides and/or rear surfaces of the housing move tend to move upward into an upper portion of housing, further increasing the temperature within the upper housing. The combined heat within the housing may exceed the ability of vents in the upper surface of the housing to effectively cool the antenna. Accordingly, it is desirable to more effectively vent heat from within an antenna housing.
The rear shroud 150 includes a rear sidewall or surface 152, two elongated sidewalls 154a, 154b, an upper end wall 156 and a lower end wall 158. The sidewalls 154a, 154b (hereafter 154 unless specifically referenced) and end walls 156, 158 extend from the rear surface 152 to define a generally recessed interior of the rear shroud 150. That is, a forward or inside surface 160 of the rear shroud 150 is open and recessed. In the illustrated embodiment, the sidewalls and ends walls generally define a frustum. However, this is not a requirement. A backing plate assembly 190 attached to the to the rearward and side surfaces of the antenna unit 170 via various fasteners. Additionally, the backing plate assembly 190 provides connection points for attaching the front and rear shrouds. When assembled, peripheral edges of the end walls and sidewalls of the rear shroud 150 engage with peripheral edges of the end walls and sidewalls of the front shroud 130. The resulting housing 120 has an interior sized to receive the antenna unit 170. Variation of the housing is possible. By way of example, the front shroud may be similar to that described above while the rear shroud may be a substantially flat panel. What is important is that the housing define an interior area sized to house an antenna unit.
In the illustrated embodiment, the antenna unit 170 is a Streetmacro 6701 antenna produced by Ericsson. It will be appreciated that the antenna housing 120 disclosed herein may be utilized with a variety of antennas and that this particular antenna is presented by way of example only. Nonetheless, the Streetmarco antenna unit is representative of a general form of many 5G antenna units currently being installed. As illustrated, the antenna unit 170 includes a generally rectangular prism-shaped housing having a front surface 172 that includes the radome 173, which is a thin walled RF transparent area that protects the forward emitting surface of an RF antenna. The antenna further includes two elongated sidewalls 174a, 174b (hereafter 174 unless specifically referenced), a top end surface 176 a bottom end surface 178 and a rear surface 180. In addition, the antenna unit 170 includes an internal cooling duct 182 (shown in phantom in
To provide cooling for the antenna unit 170 when disposed within the housing 120, the housing includes a number of vents. The illustrated vents are formed as a plurality of elongated apertures extending through various surfaces of the antenna housing. Variation is possible. What is important is that the housing has a number of vent apertures, which in the present disclosure provide substantially sperate air flow paths through the housing 120. As illustrated, the bottom wall 138 of the front shroud 130, which is also the bottom surface of the housing in the illustrated embodiment, includes a vent 20 that allows air to enter into an interior of the lower portion of the housing. The top surface 136 of the front shroud, which is also the top surface of the housing in the illustrated embodiment, also includes a vent 22 that allows heated air to exit from the interior of the housing. Additionally, the side surfaces 134a, 134b include a first set of sidewall vents 24a, 24b, extending through the sidewalls. The first set of sidewall vents 24a, 24b are located toward the upper end of the sidewalls 134a, 134b (e.g., where the sidewalls 134 meet the upper wall 136). The first set of sidewall vents provide an exhaust exit on the sidewalls for spaces between the side surfaces of the antenna unit and on the sidewalls of the housing. The sidewall may also include an optional second set of sidewall vents 25a, 25b disposed through the sidewalls 134a, 134b, respectively, at a location above the first set of sidewall vents 24a, 24b. These sets of sidewall vents 24a, 24b and 25a, 25b, while each opening into an interior of the housing, may open to interior spaces that are at least partially isolated to define separate flow paths for cooling purposes. In the illustrated embodiment, the two sets of vents are separated by deflector plates 192a, 192b, as further discussed below.
The rear surface of the housing 120 as defined by the rear shroud 150, in the illustrated embodiment, includes two sets of vents. A first set of vents 26a, 26b extend through the rear surface 152 and/or sidewalls 154 to provide passive cooling (e.g., driven by thermal convection) for a space between the rear surface 180 of the antenna unit 170 and the inside surface 160 of the housing. The second set of vents 28 and 30 may provide venting for the cooling duct 182 of the antenna unit. In this regard, the second set of vents includes a lower air intake vent 28 and an upper air outlet vent 30 that extend through a surface of the shroud 150. In an embodiment, the intake vent 28 connects to the inlet 184 of the antenna unit cooling duct 182 via an intake duct 40 and the outlet vent 30 connects to the outlet 186 of the antenna unit cooling duct 182 via an outlet duct 42. These ducts, 40, 42 allow the antenna unit 170 to draw air from outside of the housing 120 through the cooling duct 182 (i.e., over a heat rejecting surface(s) of the antenna unit) and expel the air out of the housing 120. Such air may pass through the housing 120 without intermingling with air in the interior of the housing. In the absence of the inlet duct 40 and outlet duct 42, heated air from internal cooling duct 182 of the antenna unit 170 would be drawn from the interior of the antenna housing 120 and expelled back into the interior of the antenna housing 120. This would result in inefficient cooling of the antenna and an increased temperatures within the antenna housing.
To allow for drawing ambient air from outside of the antenna housing for cooling the antenna unit, the inlet duct 40 is attached to the bottom surface of the antenna unit 170 such that a hollow interior of the inlet duct 40 is in fluid communication with the inlet of the antenna cooling duct 182. See
As illustrated, the inlet duct 40 is a generally hollow structure having a sidewall 43 that extends from an inlet opening 44 to an outlet opening 46. In the illustrated embodiment, the inlet opening 44 includes two openings disposed side-by-side. However, it will be appreciated that a single opening may be utilized. As shown, front edge surfaces of the two inlet openings 44 are contoured for substantially flush engagement with a rear surface of the housing around the inlet vent 28 formed through the rear shroud 150 of the housing, when the antenna housing is assembled. Further it will be appreciated that a gasket may be disposed around the periphery or peripheries of the inlet(s) 44. Such a gasket may seal an interface between the inlet and the periphery the inlet vent 28 in the shroud, when the antenna housing is assembled. The outlet opening 46 is configured for engagement with the antenna unit 170. In this regard, the outlet may be contoured to engage a specific antenna unit. In an embodiment, a peripheral surfaces around the outlet opening contain an adhesive (e.g., pressure sensitive tape) for attaching the inlet duct 40 to the antenna unit 170. Other connection mechanisms are possible. Likewise, the outlet duct 42 is a generally hollow structure having a sidewall 53 that extends from an inlet opening (not shown) to an outlet opening 56. The inlet opening is configured for engagement with the outlet opening 186 in the top end surface 176 of the antenna unit 170. In this regard, the inlet opening may be contoured to engage a specific antenna unit. As above, the outlet opening may engage with the outlet vent 30.
In the illustrated embodiment, both the inlet duct 40 and outlet duct 42 are generally elbow-shaped. That is, each duct 40,42 has an inlet opening and an outlet opening that are generally disposed in different planes. This shape allows the ducts to extend to or through the sidewall surface (e.g., shroud) of the antenna housing while being able to connect to top and bottom surfaces of the illustrated antenna unit. However, it will be appreciated that the configuration of the ducts may be varied based on a configuration of the antenna housing and/or a configuration of an antenna unit disposed within the housing. What is important is that the ducts are configured to extend from openings or vent in a sidewall or end wall surface of the antenna housing and extend to a duct that is utilized to cool the antenna.
As noted above, the housing is sized such that a space exists between the sidewalls 174 of the antenna unit 170 and the sidewalls 134 of the housing. These spaces each define a separate flow path through the interior of the housing for use in cooling the housing. Further, these separate flow paths are particularly suited for dissipating heat resulting from solar radiation impinging on the outside surfaces of the housing 120. This is best shown by the partial cross-sectional view of
The foregoing description has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the inventions and/or aspects of the inventions to the forms disclosed herein. Consequently, variations and modifications commensurate with the above teachings, and skill and knowledge of the relevant art, are within the scope of the presented inventions. The embodiments described hereinabove are further intended to explain best modes known of practicing the inventions and to enable others skilled in the art to utilize the inventions in such, or other embodiments and with various modifications required by the particular application(s) or use(s) of the presented inventions. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art.
The present application is a continuation-in-part of U.S. patent application Ser. No. 16/837,234 having a filing date of Apr. 1, 2020, the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16837234 | Apr 2020 | US |
| Child | 17156779 | US |
