Operation Manual

21
Taking measurements
Gigaset N720 DECT IP Multicell System / engbt / A31008-M2316-L101-2-7619 / measure.fm / 10.02.2012
Version 2, 06.08.2010
u Document the progress of the measurement by entering it in the layout plan (horizon-
tally and, where applicable, vertically) and in a measurement log.
u In order to be able to recognise subsequent changes, it is helpful to document the
planned assembly positions of the individual measurement series and their environ-
ment with photographs.
u If the PABX is to be used for several floors or very high rooms (e.g., with a gallery), you
must also measure the vertical range and enter it in a plan of the building. For further
information on this, please also refer to the DECT installations in special environ-
ments chapter
£ page 41.
Fluctuations in the measurement result
When you are performing the measurements, the signal strength displayed on the hand-
set can fluctuate strongly, particularly if you are moving around with the handset. The
base stations have two aerials, so the handset displays the values for the aerial for which
it receives the best signal. Since the measuring handset takes measurements at defined
time intervals (2.5 seconds as standard), the values can change quickly.
For example, if you block the signal for the aerial that is in a better position for the handset
with part of your body, the handset receives the signal from the weaker aerial. Turning
your body slightly can significantly alter the measurement value, since the handset is sud-
denly able to receive the signal from the "better" aerial. By moving around, you determine
an average value that you can use as the measurement value.
If the fluctuations are strong, it makes sense to perform the measurement while a connec-
tion is established as you then have an additional check based on the voice quality.
When the PABX is being operated in real-life situations, these fluctuations are barely
noticeable as the base stations automatically establish the connection with the best posi-
tioned aerial.
Defining limit values
During the measurement process, the measuring handsets receive wireless signals from
the measuring base station and display various characteristics for the reception quality.
The following are relevant for the reception quality:
u Reception power
u Connection quality
The values specified below are guidelines for determining limit values for operating the
DECT telephone system under optimum conditions. Since the DECT network can be
restricted by many factors that can also occur temporarily, we do not recommend posi-
tioning the base stations at the limit values. Instead, you should include a buffer accord-
ing to the requirements for grade of service and voice quality. It may be acceptable for
example, that voice quality is restricted at times in the basement, and that calls cannot
always be made there. In contrast, restrictions are unacceptable for meeting rooms where
telephone conferences are held.