R&S M3SR 4100 Series, Operating Manual

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M3SR Series 4100 Switching the Occupancy Detection On or Off
4.106 Operating Manual 6175.4760.02 – 01
4.4.5.16 Switching the Occupancy Detection On or Off
Softkey Type Description
Toggle 1. Press softkey to toggle Occupancy Detec-
tion on/off.
The new value is effective immediately.
Possible values:
• ON
• OFF
If occupancy detection is switched to on,
known waveforms will be detected and prohib-
its the link setup. If switched to off, no listen be-
fore transmit will be performed.
The ALE-3G is provided with a highly sophisti-
cated waveform detection system which is
called occupancy detection (OD) or listen be-
fore transmit (LBT). The feature could be used
in synchronous and asynchronous mode and
detects all waveforms which are shown in the
table below. If the feature was activated the
ALE-3G performs before every outgoing call a
listen before phase with a duration of 900ms.
If a known waveform on channel was detected
a message will be displayed in a way like
"channel occupied hf-modem".
In cases that a radio could not link in matter
of a local disturbance it is may be helpful to
deactivate the occupancy detection feature
to establish a link. Otherwise the operator
shall keep in mind that the transmitted or
received PDU (Protocol Data Unit) is cor-
rupted if the occupancy detection is deac-
tivated.