Installation manual

IP DECT Installation Page 20
15-601085 Issue 04f (11 June 2009)IP Office
2. Site Survey and Planning
Coverage In Theory
Given ideal open field conditions, the range between a handset and base station can be up to 600 metres (approximately
2000 feet). However where obstacles absorb signal strength and reflected signals giving increased error rates, the range
is more realistically between 30 metres (98 feet) indoors and 300 metres (984 feet) outdoors.
Coverage In Practice
In practice, no rules or guarantees can be given for base station coverage. Coverage is affected by too many factors that
are unique to each site. The following is a guide to those factors that can affect coverage and should be considered
during any site survey.
· Obvious causes of signals problems:
· Metal surfaces.
· Concrete thickness greater than 1 metre (3 feet).
· Also beware of:
· Windows with Reflective Film or Specialized Glass.
These produce increased signal reflection and reduced signal pass-through.
· Wire Meshes and Grills with Apertures of Less than 4cm (1.5 inches).
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.
· Empty Sites
Do not perform a survey on a site that is not yet occupied. The survey results will differ from those of the
same site once occupied by the customer business.
· Be Aware of:
· Signal Direction
The signal from a base station does not propagate evenly in all directions. The signal typically propagates
strongest in the horizontal plane. However the ability for a base station to serve callers located on floors
above or below it should not be ignored. This may allow coverage to be extended to areas not frequently used
and so not meriting a dedicated local base station.
· By default all the base stations are omni-directional. For the RFP33 and RF34, the aerials are connected
by TNC connectors and can be replaced with beam or dipole aerials. The use of beam aerials is not
supported in North America. The use of third-party aerials is not supported by Avaya.
· Radio Signals
The ability to receive normal broadcast radio signals in an area is not an indication that DECT signalling will be
received.