Site Surveys - Page 7
Compact DECT - Installation Manual
Page 7
38DHB0002UKFH – Issue 5 (27th October 2003)
Base Station Coverage: In Theory
Base Station Coverage: In Theory
Given ideal open field conditions, the range between a handset and base
station can be up to 600 metres. Within a building, with signal strength being
absorbed and reflected signals giving increased error rates, the effective
range (R) is more realistically between 50 metres and 150 metres.
A single base station's area of coverage is
Π
xR
2
.
Base Station
R
Be aware that the following is assumed:
– The building structure is even and so the CDBS has the same range in
all directions.
– That a CDBS does not only operate in 2-dimensions. In reality the signal
forms a sphere rather than a circle.
Base Station Coverage: In Practice
In practice, no rules can be given for base station coverage. Coverage is
affected by too many factors that are unique to each site. We can only guide
you as to those things that are likely to affect base station coverage.
Obvious causes of signals problems:
Metal surfaces.
Concrete thickness greater than one metre.
Beware of:
Windows with reflective film or specialised glass: (e.g. Pilkington 'K')
These produce increased signal reflection and reduced signal pass-
through.
Wire Meshes and Grills with apertures of less than 4cm:
These block signals as effectively as continuous metal sheet.
Fire Doors:
These block the signals. In multi-occupancy building such as hotels the
high number of fire-doors may be a problem.
Stair Wells:
In modern office buildings, stair wells frequently combine concrete building
supports, fire doors and the intervening floor material, making them a
special problem.
Screened Rooms:
Typically found in offices involved with TV, video and radio production, but
also possible in computer centers.
Opportunities to be aware of:
In multi-storey buildings, if the building construction allows, a base station on
one floor can also serve the floor above or below.