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<br /> Association of Telecommunications Officers and and lattice,or self-support cowers,which have three or four
<br /> Administrators, the U.S.Conference of Mayors,the National sides of open-framed steel supports.Some cellular antennas can
<br /> League of Cities,and the National Association of Counties have occupy space on ocher types of communication towers when the
<br /> filed similar objections. engineering is feasible.This is known'as using a donor size to
<br /> troubleshoot a small gap or dead spot within the grid.A micro-
<br /> Hafnre of tbo T el6ao16" cell or repeater facility is installed on a preexisting tower to
<br /> Low-power mobile radio communication,also known as cellular ensure chat transmissions within that area tae clear.Antennas
<br /> communication,is accomplished by linking a wireless network tan also be placed on roofiops and ocher building features if the
<br /> of radio wave transmitting devices(portable phones,pagers,or building's height an accommodate their service arcs. In
<br /> car phones) co the conventional ground-wired communications addition,antennas have been mounted on silos,water tanks,
<br /> system(telephone lines) through a series of short-range, windmills,and smokestacks.As cellular use proliferates and the
<br /> contiguous cells that are part of an evolving cell grid. technology improves, the trend coward shorter towers and less
<br /> For example,a portable phone transmits a signal co the obtrusive mounting fixtures is likely to prevail.
<br /> nearest cellular antenna.The call is relayed from the antenna to Antennas are of three types:omnidirectional,directional,and
<br /> the nearesc land-based telephone line or microwave dish,and microwave. Omnidirectional antennas,also called whip
<br /> then to a central switching computer. From there,.the call is antennas,serve a 360-degree area.Directional antennas,also
<br /> sent to its destination,either a landrbased telephone via the known as panel antennas or rectangular antennas,are used to
<br /> land-based line or another mobile communiadon device via the achieve transmission or reception in a specific direction.
<br /> closest cellular antenna. Microwave antennas are used to link different types of
<br /> Calls can originate or be received from a wireless source telecommunications facilities,such as when a portable phone
<br /> bemuse antennas share a faced number of frequencies across the user calls a conventional telephone number.
<br /> cellular grid.In other words,while a caller may dial her destina-
<br /> tion number from within the radius of one cell antenna,she may Screening, Landscaping, and Setbacks
<br /> travel into the radius of another during the call.The call proceeds The most common objection to cellular cowers and antennas is
<br /> uninterrupted as the transmission is"patched"from one antenna their aesthetic impact.Residents,many of whom use the
<br /> co the next.While the caller is moving,the cellular antennas are technology,do noc want to see the towers cluttering their
<br /> automatically locating an unoccupied frequency on the next landscape or degrading property values.Planners and industry
<br /> antenna, thus enabling continued transmission. professionals have gone to great lengths to screen,conceal,and
<br /> When a caller cannot successfully place or maintain a call, set back cowers and their associated buildings.All the
<br /> either he is our of range or the nearest antenna is at full ordinances reviewed contain some sort of requirement for
<br /> capacity.Cellular tower technology differs from satellite, maintaining existing vegetation or installing landscaping for the
<br /> microwave,or land-based communications in that its based on purpose of screening the base of the tower and the storage
<br /> a network of short-range cell sites with a fixed capacity.If the building.Towers can also be camouflaged to blend with the
<br /> cells are not linked by cellular towers,microwave dishes,or surrounding environment through the use of color, materials,
<br /> ground-wired towers,transmission will fail.Similarly,if a cell is and design. For instance,Jefferson Parish,Louisiana,requires
<br /> crowded by coo many users,is must be"split"into two cells, that all cellular towers be disguised as trees:
<br /> each having its own radius:thus,only the cellular antennas of 1.The entire facility must be aesthetically and architecturally
<br /> separate carriers can share space on the same tower.It is compatible with its environment.The use of residentially
<br /> physically impossible for a single carrier to deliver service compatible materials such as wood.brick,or stucco is
<br /> successfully if its antennas are not dispersed. required for associated support buildings,which shall be
<br /> Most local regulations require that all technically available designed to architecturally match the exterior of residential
<br /> space on existing cowers within the jurisdiction be used before structures within the neighborhood.In no rase will metal
<br /> new towers are erected.In other words,cellular carriers must _ _ernriocs be allowed for accessory buildin .
<br /> lease space to ocher carrier:on their towers:the cellular indusay --2.The cower itself must be of such design and creaced avidLan
<br /> considers this leasing arrangement to be a less-than-ideal architectural material so that it is camouflaged to resemble a
<br /> solution.As the demand for cellular telecommunications woody tree with a single trunk and branches on its upper put.
<br /> increases,cells in a given area must be subdivided,or additional
<br /> carriers must be permitted to opetare there.The end result is the Setback distances can be guided by aesthetic and safety
<br /> need for more towem concerns.Most are expressed as a percentage of the tower
<br /> height.In ttrg-Pensacola,Florida,ordinance,the setback serves a
<br /> Towers mad Awlemeas primarily aesthetic purpose:
<br /> Towers may need.to nn¢in hertz from 50 to 200 feet so that (Tlhe distance between the base of the communications towers
<br /> antennas can overcome the challenges posed to communications and any residential zoning district or any historical or
<br /> by local topography.The requited height is usually proportional to architecturally significant building must equal 20 percent of the
<br /> a combination of the distance antennas can cover and the demand cower height.
<br /> within their radius:Higher cowers generally cover a larger
<br /> geographic area,but have a lower service demand,and are known Safety-oriented setbacks establish a dear zone for falling
<br /> as coverage sites.Shorter cowers.known as capacity sites,cover cower debris or the worst-case scenario,the cowers collapse.
<br /> smaller areas with a more concentrated demand.Tower height can Falling zones for towers vary with their design.At most,they
<br /> also vary according to engineering requirements for a specific site will collapse to a distance equal to their full height,but many
<br /> or the technical capabilities of the antennas being mounted. are designed to collapse first toward their base.The Oldham
<br /> In addition co dedicated.free-sanding cellular cowers County,Kentucky,setback provisions are designed with falling
<br /> (monopoles),there are guyed towers(anchored with guy wires) zones in mind-
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