22
Taking measurements
Reception power
The reception field strength is measured to assess the quality of transmission. The reception
power (proportional to the field strength) is displayed on the measuring handset in
). A very good reception power is approximately –50 dBm. Systems that are
measured at up to –60 dBm generally offer a good quality. For measurements up to –70 dBm,
the measurement must be checked and evaluated with an audio connection to ensure suffi-
cient quality. A handover is no longer possible in this area.
Different limit values can be used for the measurement, based on the quality or use of
specific areas (e.g., office, corridor, basement). Different quality requirements can also be
defined at the various base stations within a partial system.
Typical limit values for normal, low-interference environments are:
§§1§§
Limit value for secured voice quality: –65 dBm
This is the value at which a handset must receive the signal of a base station for a sub-
scriber to be able to benefit from good quality telephony. For an interference-free
handover, the handset must receive both base stations at this level of quality.
§§2§§
Limit value for synchronisation: –70 dBm
This is the value at which a base station must receive the signal of another base station
to be able to synchronise.
The following table gives an initial guideline for the quality of the wireless connection.
Reception power
Evaluation of the quality
–50 dBm
Very good
–60 dBm
Good
–65 dBm
Satisfactory
–70 dBm
Adequate
–73 dBm
Weak, not suitable
–76 dBm
Poor, not suitable
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