1. Field of the Invention
The present invention is in the field of cellular radio frequency communication system antennas and in particular heat dissipation from them.
2. Related Art
Antennas for cellular radio frequency communication systems, for example cellular telephone antennas, are advantageously arranged in configurations having a length that substantially exceeds the width of the antenna. A typical antenna may be two meters long and 30 centimeters wide. These antennas are usually mounted so that their long axis is substantially vertical. They are most frequently mounted on a cell phone tower that is often as high as 200 feet.
The antennas contain electrical components including modular radios, power supplies and/or transformers, radio frequency emitters and other components. In operation, these components generate heat. This heat should be dissipated in order to keep the operating electrical components at an advantageous temperature for effective and durable operation.
The antennas usually have a radome on one side. The antennas are typically mounted with the radome outermost, and with a back surface of the antenna facing the tower, as well as other structure, antennas and equipment that may also be mounted on the tower.
Active cooling components such as fans are problematic to install high on antenna towers, and so it is desirable to dissipate heat from antennas by passive means. Preexisting designs mounted heat dissipating fins on the back of the antenna. However, these fins were vertically aligned along the length of the antenna. Air heated by the components in the lower portion of the antenna would rise along the fins. The upper portions of the fins receiving this pre-heated air could not transfer heat from the upper components of the antenna efficiently. Further complicating considerations include the presence of the antenna in the open air during normal operations and the orientation of the heat exchanging (back) surface of the antenna towards the tower structure and other equipment mounted there. Of course, economy and the fabrication of components remains a consideration.
A cellular communication antenna has a base with a length that exceeds its width and an inside surface with internal mounts for a plurality of electrical components that generate heat when in operation. A top encapsulates the electrical components and incorporates a radome. A plurality of fins are mounted on the outside surface of the base. They may be non-parallel with the length of the base. They may all be substantially the same length. They are further constructed and arranged to be in thermal communication with the electrical components such that heat generated by the electrical components is dissipated by the fins. Each fin may be in thermally conductive communication with more than one electrical component. Fins may be arranged in groups, and separated by gaps. The gaps may include baffles.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
Referring now to the drawings wherein like reference numbers indicate like elements, Cellular telephone antenna 10 includes a curved, front radome 12 and a rear housing back 14. The radome and back maintain a space therebetween in which electrical antenna components are mounted.
The cellular communications antenna 10 is dimensioned to have a length L. Electrical components are arranged generally in line along the length L of cellular communications antenna 10.
As depicted in
In the depicted embodiment the fins 16 are divided into groups 20 which in
In still air, the configuration of the present invention allows convection to create advantageous air flow through the spaces 18 and between fins 16. The configuration of the present invention is further advantageous in windy conditions, in that the opening of the spaces to the side of the antenna readily allows ingress of air into all spaces 18 between all fins 16.
Each fin is substantially the same length in the depicted embodiment. Each fin is non-parallel to the length of the overall antenna. In the depicted embodiment, the fins are at an angle between about 40 degrees and about 75 degrees from horizontal, thereby allowing convection to cause air to move through the spaces 18 between the fins 16 as the heated air rises. Vertical or near vertical angles are avoided. Fin arrays with spaces that do not open to the side of the antenna are avoided. Thus, the invention avoids air heated in the lower portion of the antenna to disadvantageously enter the space between fins dissipating heat from the top portions of the antenna.
An interior view of the base 14 is shown without electrical components in
In the embodiment depicted in
In the embodiment depicted in
In a breeze, the opening of spaces 118 and baffles 130 to the side of the fin array allows for moving air to be more readily received into the spaces 118 between fins 116, thereby further promoting cooling.
In another embodiment depicted in
In a another alternative embodiment depicted in
As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.
This application claims priority to U.S. Provisional Application No. 61/119,224 filed on Dec. 2, 2008 and to U.S. Provisional Application No. 61/119,270, also filed on Dec. 2, 2008.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US09/66260 | 12/1/2009 | WO | 00 | 7/18/2011 |
Number | Date | Country | |
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61119224 | Dec 2008 | US | |
61119270 | Dec 2008 | US |