The range of these radio cells (also called “radius”) is hig-
hly variable. In good geographic conditions and with small
amounts of users, the radius of such cells can span sever-
al km. So, in rural areas, you might travel several km until
the phone changes cells. That is why in such areas, there
are mostly only a few large base stations. In contrast, if
many users are to be expected and reception quality is
decreased, like in cities with large amounts of buildings,
walls etc., these cells might just have a radius of 100m. To
take this into account, of course, the number of radio cells
in cities must be
increased significantly
. Thus, in big
cities like Munich, you will find hundreds of individual radio
cells. As even the capacity and range of these cells is often
not sufficient, they are often subdivided once more into
smaller, so-called micro cells. If even these are not small
enough, they are further subdivided into the so-called pico
cells. Micro and pico cells are very inconspicuous as they
are mostly mounted without any kind of mast or tower and
are also of an extremely small size by themselves. Thou-
sands of micro and pico cells can be found in most cities,
often on the walls of buildings, but also inside buildings.
As peoples’ acceptance of mobile communications facili-
ties constantly decreases, though, they are increasingly
being
disguised
. They are hidden in billboards, company
logos, spires, below roofs etc. For the new generation of
mobile communications (
UTMS
), the number of cells will
need to be tripled, meaning that hundreds of thousands of
new, well disguised cells will become necessary. These will
only be detectable with high-performance measurement
equipment like SPECTRAN.
Thus, you should keep checking your personal exposure
monthly, even though you can’t
see
any new antennas.
Would you have known?
Disguised base station
in a spire
Very hard to find:
A micro cell on a buil-
ding wall, above and
below a billboard
Radio cell map divided
into base stations,
micro- and pico cells
15.0 RF exposure in practice
54
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
Содержание SPECTRAN HF-2025
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