Mitel MiVOICE BUSINESS, Инструкция по инженерии

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Phones and Voice Applications
71
TYPICAL OPERATING RANGE
Based on the building material and the number and type of obstructions within the operating
space, you can roughly calculate the coverage area for an individual Cordless Module. It is still
necessary, however, to carry out a thorough planning survey to guarantee coverage.
Typical Attenuation of building materials at 1.9 GHz (values are approximate) are listed below:
The output of a Cordless Module is determined at +20 dBm. The minimum receive field strength
is given as -83 dBm in the DECT Standard. There remains a theoretical range of approximately
100 dB. This range is dependent on a number of environmental factors and is practically reduced
to 85 dB.
Therefore the operating range in an unobstructed open space is between 100 m and 300 m
(300' to 900').
The operating range in a typical office environment will be reduced due to obstructions and
interference to approximately 50 m (150') for the Mitel Cordless (DECT) Handset and 30m
(100') for the Mitel Cordless Headset.
RANGE EXAMPLE
The radio cell can penetrate only one brick wall.
• Maximum dynamic range + 85dB
• Brick wall at customer site -12 dB
• Remaining dynamic range + 73 dB
As the open space attenuation for a radio cell length of 50 m already stands at 72 dB, the
distance of the Handset/Headset from the installed Cordless Module should be less than 50
m. Performance may vary due to building construction, office furniture and radio frequency
interference. The impact of interference and obstructions can be minimized by conducting an
RF site survey prior to installation.
RF SITE SURVEY
For installations that call for only a small quantity of cordless accessories a simple trial and
error test with the actual cordless accessories might be sufficient to ensure satisfactory
operation.
Inner partition walls 2-5 dB
Wood-/thin material walls 5 dB
Steel shelves/cupboards 15 dB
Various brick types 6-12 dB
Concrete walls 10-20 dB
Concrete ceilings 20 dB
Elevator cars 20-30 dB