Abstract:
A device comprises a housing and antenna elements. The housing has an outer surface portion and a plurality of projection portions. The projection portions dissipate heat and are disposed to extend to a first height from the outer surface portion. The antenna elements are disposed below the first height at a position of the outer surface portion and in between the projection portions. Accordingly, the antenna elements are protected by the projection portions.

Description:
BACKGROUND 
       [0001]    Cable mesh is a relatively new type of high-capacity wireless broadband delivery system. A cable mesh network comprises a cable infrastructure (e.g., a hybrid fiber-coaxial or HFC infrastructure) and a one or more cable mesh nodes deployed at various locations and interfaced directly to the cable infrastructure. 
         [0002]      FIG. 1  illustrates a conventional cable mesh node  100 . A cable mesh node such as node  100  typically includes a cable modem that connects to an HFC network and a Wi-Fi access point (AP) installed together in a common housing or enclosure. The AP includes an antenna for connecting to the cable mesh network and for providing network access to users. As illustrated in  FIG. 1 , conventional cable mesh node  100  employs bolt-on antenna elements  102   1 - 102   n  (hereinafter collectively referred to as “antenna elements  102 ”) that bolt on to a housing  104  of cable mesh node  100 . Antenna elements  102  are separate from housing  104 . As also illustrated, a typical housing  104  contains heat-dissipating fins  106  for thermal dissipation of heat. 
         [0003]    Cable mesh nodes such as node  100  are typically attached to elevated structures, such as poles, and are typically attached in areas of other utility services, such as high voltage electrical lines and public switched telephone network (PSTN) telephone lines. The operators of cable mesh nodes must typically negotiate access rights for placement of the cable mesh nodes and generally are confined to a defined area. A technician typically must carry the housing of the cable mesh node up a ladder and mount the housing on the pole, for example. Then, the technician typically must also mount the antenna onto the housing (and the pole), which often requires a mechanical support rod to secure the antenna. Accordingly, the size and bulkiness of the AP often makes installation of a cable mesh node difficult, time consuming and potentially hazardous, due to the potentially close proximity to high voltage electrical lines. 
         [0004]    An improvement on the previously described conventional cable mesh node is disclosed in U.S. patent application Ser. No. 11/734,494 (the &#39;494 application) to James Rahm, the entire disclosure of which is incorporated herein by reference. In the &#39;494 application, and for example as illustrated here in  FIG. 2 , antenna elements are integrated into housing  206  of a cable mesh node  200 . Housing  206  of cable mesh node  200  includes an upper half  202  and a lower half  204 . The interior of upper half  202  includes beam forming electronics  208 , which are electrically connected to antenna elements  210   1 - 210   n  (hereinafter collectively referred to as “antenna elements  210 ”). Exterior to upper half  202  are a plurality of heat-dissipating fins  214   1 - 214   n  (hereinafter collectively referred to as “heat-dissipating fins  214 ”). Antenna elements  210  are aligned with heat-dissipating fins  214  and fixed to and separated from antenna elements  210  by way of dielectric spacers  212 . With this type of structure that includes antenna elements on the heating elements of the cable mesh node, no additional mechanical support is required to secure the antenna. However, as antenna elements  210  are on top of heat-dissipating fins  214 , they are susceptible to damage. Further, this type of structure does not eliminate the need for additional mechanical volume in the cable mesh node. 
         [0005]    What is needed is a cable mesh node with an integrated antenna that does not require additional mechanical volume and is less susceptible to damage. 
       BRIEF SUMMARY 
       [0006]    In accordance with an aspect of the present invention a device comprises a housing and an antenna element. The housing has an outer surface portion and a projection portion. The projection portion is disposed to extend to a first height from the outer surface portion. The antenna element is disposed below the first height at a position of the outer surface portion. 
         [0007]    Additional advantages and novel features of the invention are set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
     
    
     
       BRIEF SUMMARY OF THE DRAWINGS 
         [0008]    The accompanying drawings, which are incorporated in and form a part of the specification, illustrate an exemplary embodiment of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings: 
           [0009]      FIG. 1  illustrates a plan view of a conventional cable mesh node; 
           [0010]      FIG. 2  illustrates a cross-sectional view of a cable mesh node with an integrated antenna; 
           [0011]      FIG. 3  illustrates a cross-sectional view of a cable mesh node having a heat-dissipating projection and an antenna element in accordance with an exemplary embodiment of the present invention; 
           [0012]      FIG. 4  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and an antenna element in accordance with another exemplary embodiment of the present invention; 
           [0013]      FIG. 5  illustrates a cross-sectional view of a cable mesh node having a heat-dissipating projection and more than one antenna element in accordance with another exemplary embodiment of the present invention; 
           [0014]      FIG. 6  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the heat-dissipating projections have the same height, in accordance with another exemplary embodiment of the present invention; 
           [0015]      FIG. 7  illustrates a plan view of the cable mesh node of  FIG. 6 ; 
           [0016]      FIG. 8  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the heat-dissipating projections do not have the same height, in accordance with another exemplary embodiment of the present invention; 
           [0017]      FIG. 9  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the antenna elements are disposed on an outer portion of the housing, in accordance with another exemplary embodiment of the present invention; 
           [0018]      FIG. 10  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the antenna elements are disposed in an outer portion of the housing, in accordance with another exemplary embodiment of the present invention; and 
           [0019]      FIG. 11  is an oblique view of a cable mesh node in accordance with another exemplary embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Several exemplary cable mesh nodes in accordance with the present invention, for use with broadband cable television (CATV) mesh systems, will be described with reference to  FIGS. 3-11 . 
         [0021]      FIG. 3  illustrates a cross-sectional view of a cable mesh node having a heat-dissipating projection and an antenna element in accordance with an exemplary embodiment of the present invention. Cable mesh node  300  includes a housing  302 . Beam forming electronics  310  are disposed within housing  302 . Disposed atop housing  302  is heat-dissipating projection  306 . In this embodiment, heat-dissipating projection  306  is an integral part of housing  302 . Set into housing  302  is antenna element  308 . Specifically, in this embodiment, the upper surface of antenna element  308  is flush with the outer surface of housing  302 . 
         [0022]    The positional relationship between heat-dissipating projection  306  and antenna element  308  enables heat-dissipating projection  306  to protect antenna element  308  from damage. If, during installation or use, an object were to come into contact with cable mesh node  300 , the height of heat-dissipating projection  306  above housing  302  and the fact that antenna element  308  is recessed into housing  302  results in the object impacting heat-dissipating projection  306 , protecting antenna element  308 . 
         [0023]    In this embodiment, because beam forming electronics  310  only control a single antenna element, antenna element  308 , they may be of very rudimentary design, e.g., an on/off switch. 
         [0024]      FIG. 4  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and an antenna element in accordance with another exemplary embodiment of the present invention. In the figure, cable mesh node  400  includes a housing  402 . Beam forming electronics  412  are disposed within housing  402 . Disposed atop housing  402  are heat-dissipating projections  406  and  408 . Set into housing  402  is antenna element  410 . 
         [0025]    In this embodiment, a plurality of heat-dissipating projections  406  and  408  provide better heat-dissipation than a single heat-dissipating projection, such as projection  306  as shown in  FIG. 3 . Further, positional relationship between heat-dissipating projections  406  and  408  and antenna element  410  enable heat-dissipating projections  406  and  408  to protect antenna element  410  from damage in a manner similar to the embodiment discussed above with respect to  FIG. 3 . Specifically, if, during installation or use, an object were to come into contact with cable mesh node  400 , the height of heat-dissipating projections  406  and  408  above housing  402  and the fact that antenna element  410  is recessed into housing  402  results in the object impacting heat-dissipating projections  406  and  408 , protecting antenna element  410 . Still further, based on well known Maxwell&#39;s equations, the spacing, size, shape and material of heat-dissipating projections  406  and  408  can be chosen to optimize the performance of antenna element  410 . 
         [0026]    Similar to the embodiment discussed above with reference to  FIG. 3 , in this embodiment, because beam forming electronics  412  only control a single antenna element, antenna element  410 , they may be of very rudimentary design, e.g., an on/off switch. 
         [0027]      FIG. 5  illustrates a cross-sectional view of a cable mesh node having a heat-dissipating projection and more than one antenna element in accordance with another exemplary embodiment of the present invention. In the figure, cable mesh node  500  includes a housing  502 . The inner portion of housing  502  includes Beam forming electronics  512  are disposed within housing  502 . Disposed atop housing  502  is heat-dissipating projection  506 . Set into housing  502  are antenna elements  508  and  510 . 
         [0028]    In this embodiment, a plurality of antenna elements  508  and  510  allow for advanced beam shaping by beam forming electronics  512 . Beam forming electronics  512  may use techniques including, but not limited to, magnitude adjustment and phase delay to steer or amplify the beam. 
         [0029]    Similar to the embodiments discussed above, the positional relationship of heat-dissipating projection  506  and antenna elements  508  and  510  enables heat-dissipating projection  506  to protect antenna elements  508  and  510  from damage. Further, the size, shape and material of heat-dissipating projection  506  can be chosen to optimize the performance of antenna elements  410 . 
         [0030]      FIG. 6  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the heat-dissipating projections have the same height, in accordance with another exemplary embodiment of the present invention.  FIG. 7  illustrates a plan view of cable mesh node  600 . In  FIGS. 6 and 7 , cable mesh node  600  includes housing  602  comprising a lower section  604  and upper section  606 . In this embodiment, upper section  606  contains beam forming electronics  612 , a plurality of heat dissipating projections  608   1 - 608   n , and waveguide elements  614   1 - 614   n . Also in this embodiment, section  606  has a portion of thicker metal  610  to increase the rigidity of housing  604 . 
         [0031]    Each of waveguide elements  614   1 - 614   n  rest in one of cavities  616   1 - 616   n  and are flush with the upper surface of upper section  606 . In one embodiment of the present invention, each of cavities  616   1 - 616   n  has a corresponding waveguide element  614   1 - 614   n . In other embodiments, some of cavities  616   1 - 616   n  may be empty or the associated waveguide element  614   1 - 614   n  may be non-radiating. 
         [0032]      FIG. 8  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the heat-dissipating projections do not have the same height, in accordance with another exemplary embodiment of the present invention. In the figure, cable mesh node  800  includes housing  802  having outer portion  804 . The inner portion of housing  802  includes beam forming electronics  812 . Disposed atop outer portion  804  is a plurality of heat-dissipating projections  806 , wherein some of plurality of heat-dissipating projections  806  extend to different heights above outer portion  804 . Set into outer portion  804  are antenna elements  808 . 
         [0033]    This embodiment illustrates that heat-dissipating projections  806  are not equal in height. These height differences may be determined to provide specific heat transfer characteristics in addition to meeting specific volume requirements for a particular cable mesh node. Further, the spacing, size, shape and material of heat-dissipating projections  806  can be chosen to optimize the performance of antenna elements  808 . 
         [0034]      FIG. 9  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the antenna elements are disposed on an outer portion of the housing, in accordance with another exemplary embodiment of the present invention. In the figure, cable mesh node  900  includes housing  902  having outer portion  904 . The inner portion of housing  902  contains beam forming electronics  910 . Disposed atop outer portion  904  is a plurality of heat-dissipating projections  906 . 
         [0035]    In this embodiment, antenna elements  908  are disposed on top of outer portion  904 . The positional relationship between heat-dissipating projections  906  and antenna elements  908  enables heat-dissipating projections  906  to protect antenna elements  908  from damage, in a manner similar to the embodiments discussed above. Further, the spacing, size, shape and material of heat-dissipating projections  906  can be chosen to optimize the performance of antenna elements  908 . Additionally, in contrast to the embodiment illustrated in  FIG. 7 , having antenna elements  908  on top of outer portion  904  may result in simpler manufacturing of cable mesh node  900  or may allow outer portion  904  to be thinner while still maintaining the desired rigidity of housing  902 . 
         [0036]      FIG. 10  illustrates a cross-sectional view of a cable mesh node having more than one heat-dissipating projection and more than one antenna element, wherein all the antenna elements are disposed partially within an outer portion of the housing, in accordance with another exemplary embodiment of the present invention. In the figure, cable mesh node  1000  includes housing  1002  having outer portion  1004 . The inner portion of housing  1002  includes beam forming electronics  1012 . Disposed partially within outer portion  1004  is a plurality of heat-dissipating projections  1006 , the plurality of heat-dissipating projections  1006  extending different heights above outer portion  1004 . 
         [0037]    In this embodiment, antenna elements  1008  are disposed partially within outer portion  1004  so as not to be flush. The positional relationship between heat-dissipating projections  1006  and antenna elements  1008  enables heat-dissipating projections  1006  to protect antenna elements  1008  from damage in a manner similar to the embodiments discussed above. Further, the spacing, size, shape and material of heat-dissipating projections  1006  can be chosen to optimize the performance of antenna elements  1008 . Additionally, in contrast to the embodiment illustrated in  FIG. 7 , having antenna elements  1008  disposed partially within outer portion  1004  may allow outer portion  1004  to be thinner while still maintaining the desired rigidity of housing  1002 . Further, in contrast to the embodiment illustrated in  FIG. 9 , having antenna elements  1008  disposed partially within outer portion  1004  may provide more rigidity of antenna elements  1008 . 
         [0038]      FIG. 11  is an oblique view of a cable mesh node  1100  in accordance with another exemplary embodiment of the present invention. Housing  1102  of cable mesh node  1100  includes a left side  1104 , a top side  1106 , a front side  1108 , a bottom side  1110 , a back side  1112  and a right side  1114 . Heat-dissipating projections  1116  extend from top side  1106  and are parallel to left side  1104  and right side  1114 . Heat-dissipating projections  1118  extend from fronts side  1108  and are shown at an angle. Heat-dissipating projections  1120  extend from bottom side  1110  and are parallel to left side  1104  and right side  1114 . Heat-dissipating projections  1122  extend from  1112  and are angled similar to heat-dissipating projections  1118 . As shown, the heat-dissipating projections may be on any side of the housing and may be positioned at varied angles with respect to the housing. 
         [0039]    Antenna elements may be disposed in housing  1102  in accordance with the present invention in any combination of the embodiments discussed above. Further, such antenna elements may be combined with one or a plurality of beam forming electronics to customize beam steering characteristics. 
         [0040]    In the embodiments discussed above, the antenna elements have a rectangular shape. In other embodiments, the antenna elements may have a different shape including, but not limited to, an elliptical shape. Any shape may be used to provide desired wave propagation parameters. 
         [0041]    In the embodiments discussed above that have more than one antenna element, all the antenna elements within a single cable mesh node have the same shape. In other embodiments, the antenna elements of a single cable mesh node may have different shapes. 
         [0042]    In the embodiments discussed above, the antenna elements may be adapted to emit linearly or circularly polarized electromagnetic waves. 
         [0043]    In the embodiments discussed above, the heat-dissipating projections are shown as fins. In other embodiments, the heat-dissipating projections may have different shapes, non-limiting examples of which include spikes, or elongated dashed portions having a width wider than a spike but narrower than a fin as illustrated for example in  FIG. 7 . 
         [0044]    In the embodiments discussed above, each antenna element may be an open-ended waveguide that may comprise a hollow metal outer portion filled with one or more dielectric substances. Any known dielectric substance or combination of dielectric substances may be used to fill the hollow metal outer portion to provide desired waveguide properties. A non-limiting example of a dielectric substance includes air. If the dielectric substance, or combination of dielectric substances, is other than air, the antenna elements are more resistant to environmental damages, a non-limiting example of which includes impact. 
         [0045]    In the embodiments discussed above, the waveguide elements are illustrated as a one-dimensional array that are aligned horizontally and spaced by heat-dissipating projections, for example as illustrated in  FIG. 7 . In other embodiments, the waveguide elements comprise an n-dimensional array wherein a plurality of spaced waveguide elements are aligned vertically in addition to the horizontal alignment as illustrated in  FIG. 7 . In these other embodiments, any number of waveguide elements may be spaced vertically to provide desired wave propagation parameters. 
         [0046]    The foregoing description of various preferred embodiments of the invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments, as described above, were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.