Abstract:
A small-footprint portable modular cellular antenna site capable of being deployed on any substantially level, flat piece of ground, the cellular antenna site being easily assembled, disassembled, and moved without the aid of heavy equipment. The cellular antenna site does not require a permanent foundation, but instead is anchored by weighting with a non-damaging ballast material sufficient to support a small diameter 30 to 60 foot high antenna pole at wind speed ratings up to 100 miles per hour. The cellular antenna site includes a modular base configurable in different geometric arrangements that retains the ballast material and supports a segmented monopole antenna, an electrical cabinet, perimeter fencing with an access gate, and any auxiliary cabinets, enclosure, or shelters as may be required.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates generally to devices for cellular telephone transmission equipment and more particularly to a self-contained cellular antenna site adapted to be small in footprint, quickly assembled without the use of heavy equipment, and easily disassembled for transporting. 
   The continued proliferation and widespread use of wireless telecommunications equipment has brought with it the need for more self-contained cellular antenna sites. Typical methods of deploying cellular antennas are on permanent structures such as towers or monopoles, or on rooftops. When based on the ground, the permanent structures are normally supported on conventional foundations such as reinforced concrete slabs or pads, and often the concentrated weight of a tall antenna tower has required a relatively substantial and separate foundation member such as a deep reinforced concrete pier. Therefore, these structures often require special zoning and permitting, soil core sampling, engineering, excavation, and the use of heavy equipment and cranes to perform installation, all of which may be costly and time consuming. In addition, the time required to pour and cure a concrete foundation may delay the erection of an antenna and ultimately the operation of the cellular site. Further, such a permanent tower or monopole is not readily removed and redeployed at another site, and even if the tower or monopole itself is removed, the permanent foundation remains. 
   U.S. Pat. No. 6,131,349 [Hill] illustrates an attempt in the prior art to eliminate the need for construction of a separate foundation to support a cellular antenna tower. However, the apparatus disclosed utilizes the supporting foundation of the adjacent telecommunications equipment enclosure to provide load bearing support for the cellular antenna tower and therefore this design is not self-contained, is integrally connected to a permanent foundation, and cannot be quickly assembled or easily removed and relocated. 
   Developments in the newer generations of wireless systems have allowed both the antenna systems and the signal processing electronics packages to become smaller. A smaller antenna atop a pole of approximately 6 to 12 inches in diameter and a total height of 30 feet to 60 feet can now provide reasonable cellular coverage, enabling the design of cellular sites with decreased visual impact and decreased wind loading requirements. The present invention is designed to take advantage of these developments to provide a cellular antenna site which is much more flexible in its deployment than sites presently available. 
   Therefore, it is an object of the present invention to provide a cellular antenna site that is modular and inexpensive, and can be easily and quickly assembled, disassembled, and moved by hand without the use of heavy equipment. It is another object of the present invention to provide a cellular antenna site that is sufficiently anchored to support a small diameter 60 foot tall antenna pole under the sufficient loading to meet a 100 mile per hour wind speed rating. It is a further object of the present invention to provide a cellular antenna site that requires only a small footprint and can be situated on any relatively level and flat piece of ground. 
   It is yet another object of the present invention to provide a cellular antenna site that creates minimal environmental and visual impact in order to potentially ease zoning and permitting requirements and in order to allow for deployment in environmentally sensitive areas. It is still a further object of the present invention to provide a cellular antenna site that can accommodate an electrical cabinet and other required equipment, enclosures, or shelters, within a fenced and secure area. 
   Other objects will appear hereinafter. 
   SUMMARY OF THE INVENTION 
   The present invention overcomes the disadvantages inherent in the types of cellular antenna sites known in the prior art. The cellular antenna site of the present invention is of a modular construction that can be assembled from components and pre-fabricated sub-structures that are small and light enough to be manipulated by a team of two people. The cellular antenna site does not penetrate the ground on which it rests and can be situated on any relatively level and flat piece of ground, including a parking lot, a gravel lot, or a patch of grass or undeveloped land. 
   The base of the cellular antenna site of the present invention does not require any excavation or permanent foundation, but is instead anchored to the ground by a ballast comprising either concrete blocks, crushed gravel, poured concrete, or an equivalent material. Except in the case of poured concrete ballast, the entire cellular antenna site can be completely disassembled into its original component parts and removed from the location without leaving a trace of its having been installed. In the case of poured concrete ballast, the cellular antenna site may still be removed but it may require the removal of the entire base as one piece instead of disassembling the base into its component modules. The ballast material, when placed in the base modules, will form a substantially flat, level decking surface regardless of which of the ballast materials is actually used. 
   The cellular antenna site of the present invention, when assembled with three base modules each measuring 10 feet long by 3 feet 4 inches wide by 1 foot high and outfitted with a 6 to 12 inch diameter antenna pole ranging in overall height between 30 and 60 feet, has a nominal weight of approximately 2000 to 3000 pounds and a nominal footprint of 10 feet by 10 feet. When loaded with a ballast of concrete blocks, the site increases to a weight of about 10,000 pounds and is capable of achieving a 75 mile per hour wind speed rating. When loaded with a ballast of poured concrete, the site increases to a weight of about 15,000 pounds and is capable of achieving a 100 mile per hour wind speed rating. 
   In view of the preceding example, it is noted that due to the modular construction of the base, the site can be assembled into a wide variety of configurations and footprint dimensions, depending on the requirements of the specific deployed location. Expansion of the cellular antenna site base can be achieved by bolting additional base modules to any of the four sides of the base. It is also noted that the design concept of the cellular antenna site of the present invention can be applied using base modules of any nominal dimensions. It is further noted that the base modules need not be of rectangular shape and could in fact be of any geometric shape with straight edges to allow for interconnecting and mating with other base modules, including cooperating triangular and hexagonal shapes. 
   The base of the cellular antenna site of the present invention provides integral means for securing an electrical cabinet which houses the required telecommunications electronics, as well as means for mounting any other auxiliary enclosures, cabinets, or shelters. The base also includes integral means for mounting the hinged antenna base, so that the antenna may be first attached in a horizontal position and then erected by simply hoisting it into a vertical position about a hinge, avoiding any need for a crane. Once erected, the hinged antenna base can be secured to maintain the antenna in the vertical position. A simple weatherproof wiring harness electrically connects the antenna to the electrical cabinet. Additionally, the base of the cellular antenna site provides means for connection of a grounding stake to ensure that the entire apparatus of the present invention is properly grounded. 
   The base of the cellular antenna site further provides integral means for the mounting of fence posts to support a fence, e.g., wire mesh or wooden post, encircling the base and surrounding the antenna, electrical cabinet, and any auxiliary equipment, in addition to a hinged gate allowing easy access to the site while providing a measure of security, personnel safety, and protection of the wireless telecommunications equipment. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For the purpose of illustrating the invention, there is shown in the drawings forms which are presently preferred; it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. 
       FIG. 1  is a perspective view of the temporary cellular antenna site of the present invention. 
       FIG. 2  is a top view of the temporary cellular antenna site of the present invention shown with concrete block used as the anchoring ballast. 
       FIG. 2A  is a top view of the temporary cellular antenna site of the present invention shown with poured concrete used as the anchoring ballast. 
       FIG. 2B  is a top view of the temporary cellular antenna site of the present invention shown with gravel used as the anchoring ballast. 
       FIG. 3  is a side view of the temporary cellular antenna site of the present invention. 
       FIG. 4  is a front view of the temporary cellular antenna site of the present invention. 
       FIG. 5  is a perspective view of a partially assembled base of the temporary cellular site comprising a number of base modules attached to one another by fastening means in a predetermined configuration. 
       FIG. 6  is a perspective view of a base assembly of a second embodiment of the temporary cellular site comprising a number of base modules having a trapezoidal configuration arrayed around a smaller number of base modules having a diamond configuration attached to one another by fastening means in the arrangement shown. 
     FIG  7  is a partial perspective view of the temporary cellular site of the present invention showing the hinge between the lower and upper portions of the antenna. 
     FIG  8  is a side view of the temporary cellular site of the present invention showing the hinge between the lower and upper portions of the antenna. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The following detailed description is of the best presently contemplated mode of carrying out the invention. The description is not intended in a limiting sense, and is made solely for the purpose of illustrating the general principles of the invention. The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings. 
   Referring now to the drawings in detail, where like numerals refer to like parts or elements, there is shown in  FIG. 1  a perspective view of the temporary cellular antenna site apparatus  10 . The apparatus  10  is of modular construction comprising a base  16 , an antenna system  18 , an electrical cabinet  12 , fencing  38 , and a grounding means (not shown). An additional component required for the functioning of the apparatus  10  is anchoring ballast, which may be in the form of concrete blocks  40 , poured concrete  40   a , crushed gravel  40   b , or another equivalent material, as shown in  FIGS. 2 ,  2 A, and  2 B, respectively. 
   The apparatus  10  is fabricated as a set of components, some of which are pre-assembled into sub-structures to facilitate onsite deployment. The apparatus  10  is easily transported to a required location and can be fully assembled and commissioned by two workers in a single day. Each base module  20  is approximately 10 feet long by 3 feet 4 inches wide by 1 foot high. The dimensions of a base module  20  are constrained to keep within a manageable weight and size, noting that many other sizes, shapes, and aspect ratios could be fabricated within the same weight range. The antenna pole  14  is available in lengths from 30 feet to 60 feet. Although a single length is preferred, the antenna pole  14  may be comprised of one or more segments. The antenna pole, or elongated support means  14 , may be manufactured of metal, fiberglass, or composite materials and may be configured as either a monopole or as a lattice work tower, however for descriptive purposes, a monopole type antenna support  14  will serve as a model encompassing all of the other configurations. 
   Prior to assembly of the apparatus  10 , a location should be selected that is relatively flat and level. Acceptable site locations include a parking lot, a gravel lot, a flat rooftop capable of supporting the required weight, and a relatively flat and level patch of grass or undeveloped ground. A temporary and non-damaging installation may be achieved by using an anchoring ballast of concrete blocks  40  or gravel  40   b.  A slightly more permanent installation may be achieved by using an anchoring ballast of poured concrete  40   a.  When using the concrete block ballast  40  or the gravel ballast  40   b,  a 60 foot antenna pole  14  is capable of achieving a 75 mile per hour wind speed rating. When using the poured concrete ballast  40   b,  the wind speed rating for a 60 foot antenna pole  14  is increased to 100 miles per hour. 
   The detailed construction of the base  16  is best described in reference to  FIG. 1  and the top view shown in  FIG. 2 . The base  16  is assembled from a combination of similar base modules  20 . Each rectangular base module  20  comes pre-assembled and is formed by joining the ends of two side rails  22  with the ends of two end rails  24 . The rails are joined by bolting, welding, or other equivalent joining means. Each side rail  22  and each end rail  24  is a galvanized steel C-channel member, although a similar lightweight and strong form such as a rectangular tube or I-beam may be used. When assembled to form the frame of a base module  20 , a side rail  22  thereof is capable of being butted up against and bolted to the side rail  22  or the end rail  24  of another base module  20 ; likewise an end rail  24  thereof is capable of being butted up against and bolted to the end rail  24  or the side rail  22  of another base module  20 . In this manner, base modules  20  may be interconnected to create a base  16  of various sizes, shapes, and aspect ratios. See  FIG. 5 . 
   Further comprising each base module  20  is an expanded metal grating or screen  26  which is rigidly attached along all four of its edges to the underside of the side rails  22  and the end rails  24  thereof to form a lightweight mesh bottom of the base module  20 . The mesh bottom formed by the metal grating  26  is capable of supporting and retaining the ballast material  40 ,  40   a,  or  40   b . The ballast material of concrete blocks  40 , poured concrete  40   a  or crushed stone or gravel  40   b , when placed in the base modules  20 , will form a substantially flat, level decking surface  50  between the plurality of perimeter rails  22 ,  24  of each base module  20  of the antenna base  16  of the present invention. In each case the ballast material  40 ,  40   a  or  40   b  will extend upward to approximately the height of the perimeter rails  22 ,  24  of the base modules  20  as shown in  FIGS. 1 ,  2 ,  2 A and  2 B. In this fashion a flat, level decking surface  50  is formed using the ballast material instead of having to construct such a deck using either prefabricated materials or other materials fabricated on site. 
   Fence post sleeves  28 , integrally secured along the inner edges of the side rails  22  and the end rails  24  of the base  16 , provide a means for mounting the perimeter fencing  38 . Pre-drilled mounting holes at various positions along the side rails  22  are adapted for bolting the base plate  46  and hinged antenna base  44  and the electrical cabinet support members  42 . Optional mounting support members  48  may be connected across any base module  20  between the side rails  22  thereof, also utilizing the mounting holes, to provide additional structural integrity and to provide means to mount auxiliary equipment cabinets, enclosures, or shelters as desired. 
   Thus, each base module  20  is a rectangular frame comprising the two side rails  22 , the two end rails  24 , the metal grating  26  across the bottom thereof, the fence post sleeves  28  facing vertically upward, and the mounting means to attach the hinged antenna base  44 , the electrical cabinet support members  48 , and the optional support members  42 , as required. Once each base module  20  is positioned where desired on the ground, multiple base modules  20  are interconnected to form the base  16 . The base may be of various configurations. For example, in  FIG. 1 , four base modules  20  are connected side-to-side to form the base  16 . In another example, in  FIG. 2 , six base modules  20  are interconnected in a three by two configuration with two sets of three base modules  20  each connected side-to-side and then the two sets of three connected to each other end-to-end to form the base  16 . See also,  FIG. 5 . Other similar, and different geometric configurations may be conceived. 
   Before continuing with a further description of the base assembly  16  of the temporary cellular site, a second arrangement of interconnected base modules can be assembled. This arrangement of base modules  120  in a hexagonal base  116  is shown in  FIG. 6 . There are two types of base modules in this arrangement, a trapezoidal base module  120   a  and a diamond base module  120   b.  The trapezoidal base modules  120   a  are arrayed around three central diamond base modules  120   b.  The diamond base modules  120   b  are shown having like triangular sections of equal length legs with a support member  142  extending along the common base of the triangular sections. The dimensional relationship of this base assembly  116  is similar to the rectangular base assembly  16  in that the overall dimension across the hexagonal shape is a similar twenty (20) feet taken along a line directly through the center of the hexagon from an interconnection point between two adjacent trapezoidal base modules  120   a  to the same interconnection point between two adjacent trapezoidal base modules  120   a  on the opposite side of the hexagon. In this way the dimensional footprint of the temporary cellular antenna site remains substantially the same regardless of the base assembly configuration. 
   Each triangular section of the diamond base modules  120   b  has an external sidewall  122  for interconnecting to the outer ring of trapezoidal base modules  120   a  and to the other diamond base modules  120   b.  Likewise, each of the trapezoidal base modules  120   a  has an external sidewall  122  for interconnecting to the other trapezoidal base modules  120   a  and to the diamond base modules  120   b.  The trapezoidal base modules  120   a  also have an external sidewall  122  facing outward forming one base of the trapezoid shape. The other base of the trapezoid shape is dimensioned to be of equal length to one of the legs of a triangular section of the diamond base modules  120   b  such that the external sidewalls  122  of the base modules  120   a,    120   b  fit tightly together. The interconnecting sidewalls  122  are held together by fastening means as described in connection with the other base assembly  16 . 
   At the center of the interconnected diamond base modules  120   b  are three segmented antenna base members  144   a, b, c,  each such segment being mounted to one of the three diamond base modules  120   b.  The three segments of the antenna base  144   a, b , and  c  cooperatively engage to form a hexagonal base member  144  to which the antenna pole  14  is bolted through the respective mounting holes. To support the antenna base  144  and to keep the base from tilting from the horizontal position, support arms  150  are arranged to extend adjacent to and beneath the edges of the antenna base member  144 . The support arms  150  extend between interconnecting sidewalls  122  of adjacent triangular sections of each diamond base module  120   b,  supported at their respective approximate midpoints by the support members  142  extending across the diamond base modules  120   b.  At the center of the antenna base member  144  is a triangular reinforcing member  145  to provide added stabilization to the base connection for support of the antenna tower  14 . 
   Extending across the distance between the bases of the trapezoidal base modules  120   a  are support members  142  to provide substantial rigidity to the sidewalls  122  of the base modules. This strengthening of the base  116  provides the rigidity to withstand deformation or distortion of the base from wind forces against the elongated support member  14  and the antenna  15 . Along the downward facing edges of the sidewalls  122  of the base modules  120   a,    120   b  metal grating  126  is attached to retain anchoring ballast to provide a sufficient weight factor to withstand the wind or shear forces exerted against the antenna tower. 
   Although this embodiment has a different configuration than that of  FIGS. 1–5 , the similar elements permit for the assembly of the base systems along with the peripheral elements described more fully below in connection with the first embodiment. It is to be understood that each of the elements described below can be fitted to be used with the hexagonal base assembly  116  in a similar fashion and being attached or mounted in a similar way as that described below. 
   The next step in assembly of the temporary cellular antenna site apparatus  10  is to anchor the base  16  at its desired location. A temporary and easily removable anchoring ballast of concrete blocks  40  or crushed gravel  40   b  may be used. A more permanent but still removable ballast of poured concrete  40   a  may be used, since the metal grating  26  creates a floor for the poured concrete form that prevents the concrete from binding to the surface below. 
   As described above, the ballast material of concrete blocks  40 , poured concrete  40   a  or crushed stone or gravel  40   b , when placed in the base modules  20 , will form a substantially flat, level decking surface  50  between the plurality of perimeter rails  22 ,  24  of each base module  20  of the antenna base  16  of the present invention. The ballast material  40 ,  40   a  or  40   b  will extend upward to approximately the height of the perimeter rails  22 ,  24  of the base modules  20  as shown in  FIGS. 1 ,  2 ,  2 A and  28  creating a flat, level decking surface  50  using the ballast material instead of having to construct the decking using either prefabricated materials or other materials fabricated on site. 
   Once the base  16  is constructed and anchored with the ballast material  40 ,  40   a,  or  40   b,  the electrical cabinet  12  is mounted. The electrical cabinet support members  42  are connected across a base module  20  and secured between the side rails  22  thereof using predrilled mounting holes, at the position on the base  16  where the electrical cabinet  12  will be located. The members  42  provide structural support for mounting the electrical cabinet  12  within the perimeter fencing  38  surrounding the base  16 . The cabinet  12  may also be free standing outside of the perimeter fencing  38 , if the size of the electrical cabinet  12  and the physical constraints of the mounting location on the base  16  are exceeded. The electrical cabinet  12  is secured to the cabinet support members  42 . A grounding stake (not shown), electrically connected to the electrical cabinet  12 , is used to provide an earth ground for the electrical cabinet  12  as well as for the entire apparatus  10 . External wiring  52  connects the electrical cabinet components to the antenna  15  as described below. 
   Prior to installing the perimeter fencing  38 , the antenna system  18  is installed. First, the base plate  46  is positioned in a desired location on the base  16  and secured to the side rails  22  at the base module  20  at that location using the predrilled mounting holes. The bottom portion of the hinged antenna base  44  is mounted to the base plate  46  using appropriately sized mounting hardware. The tapered aluminum antenna pole  14 , or the bottom segment  14 C of the antenna pole, is attached in a horizontal position to the top pivoting portion of the hinged antenna base  44 . A hinge  50 , extending along an entire side, connects the top pivoting portion and the bottom portion of the hinged antenna base  44 . Additional antenna pole segments  14 B and  14 A are then added and secured to the previously mounted segment, if a segmented antenna pole is being utilized, and the antenna  15  is positioned at the top of the assembly. The assembled antenna system  18  is then erected to its standing position by being hoisted in a pivoting motion about the hinge  50  of the antenna base  44 . See,  FIGS. 7 and 8 . Once erected the antenna pole  14  is secured in a vertical position by bolting, clamping, or equivalent removable securing means. Signal connections are accomplished between the antenna  15 , along the antenna pole  14  and into the electrical cabinet  12  by means of a waterproof electrical wiring harness  52 . 
   Perimeter fencing  38  may be erected by inserting the fence posts  30  into the fence post sleeves  28  and securing the desired fencing material  32  to the fence posts  30  around the perimeter of the base  16 . The fencing may be of wire mesh, wooden post, or any similar fencing material providing securable access to the antenna system on the temporary cellular antenna system  18 , etc. A hinged access gate  36  is provided to fit between one pair of fence posts  30  to provide for personnel access to the antenna system  18 , to the electrical cabinet  12  if it is inside the perimeter fencing  38 , and to the interior of the fenced space of the apparatus  10 . 
   After assembling the base  16  from the base modules  20 , anchoring the base  16  with the ballast material  40 ,  40   a,  or  40   b,  mounting the electrical cabinet  12 , erecting the antenna system  18 , connecting the wiring harness  52  between the antenna  15  and the electrical cabinet  12 , and erecting the fencing  38  around the perimeter of the base  16 , the temporary cellular antenna site apparatus  10  is ready for use. The only external connections required are the power and communication links. The apparatus  10  can be operated for as long as is required. If and when it is desired to remove the apparatus  10  for use in another location or in favor of a more permanent cellular antenna site, the apparatus  10  may be disassembled into its component parts and removed. 
   Disassembly of the apparatus  10  is the reverse of assembly. The perimeter fencing  38  is removed by detaching the fence  32  and the hinged access gate  36  from the fence posts  30  and by removing the fence posts  30  from the fence post sleeves  28 . The wiring harness  52  is detached from the antenna  15  and the electrical cabinet  12 . The antenna pole  14  is lowered by pivoting about the hinge of the hinged antenna base  44  and is disconnected from the antenna base  44  and disassembled from the hinged base  44 . The antenna base  44  is then removed from the side rails  22  of the base module  20  to which it was mounted. The electrical cabinet  12  is removed from its support members  42 , and the support members  42  are disconnected from the side rails  22  of the base module  20  to which they were mounted. The grounding stake (not shown) disconnected from the electrical cabinet  12  and is pulled from the ground. 
   If a temporary ballast such as concrete blocks  40  or gravel  40   b  was used, this ballast is removed and the base modules  20  are disconnected from each other. If a more permanent ballast such as poured concrete  40   a  was used, removal of the ballast and disconnection of the base modules  20  from each other may not be possible and the base  16  may need to be removed as one piece. The components of the apparatus  10  may be relocated and reassembled as described previously. 
   The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, the described embodiments are to be considered in all respects as being illustrative and not restrictive, with the scope of the invention being indicated by the appended claims, rather than the foregoing detailed description, as indicating the scope of the invention as well as all modifications which may fall within a range of equivalency which are also intended to be embraced therein.