Meaning Of Parameters - R&S 4200 Series Operating Manual

R&S XU 4200
3.3.2

Meaning of Parameters

Default setting description\Default setting description "Radio".doc
TX Audio Level
RX Audio Level
TX Output Power
Level Low
TX Output Power
Level Normal
S/N Squelch
Threshold
RSSI Squelch
Threshold
Carrier Override
S/N RSSI Logical
Operation
6166.5368.02.01
This parameter refers to the modulation input (connector X5.2/3). With the
default setting, the modulation sensitivity is of 0 dBm – which means that at
an AF level of 775 mV at this 600 ohm input, the AM transmitter is driven
and modulated at 90 % modulation. The input can be configured from
−30 dBm to +10 dBm in accordance with the line infrastructure and the
incoming signal levels. The sensitivity is greatest at −30 dBm, which
means that the full modulation of 90 % modulation is achieved even at a
low level.
This parameter refers to the audio output of the AM receiver
(connector X10.2/3). With the default setting of 0 dBm, an effective level of
775 mV is applied at 60 % AM modulation of the current receive signal.
The output can be configured from −30 dBm to +10 dBm in accordance
with the line infrastructure.
Using this parameter, you can define the transmit power between 5 W and
20 W. This value is then adopted with the Low setting (see chapter
3.4.7.2).
Using this parameter, you can define the transmit power between 5 W and
50 W. This value is then adopted with the Normal setting (see chapter
3.4.7.2).
The threshold value for the signal to noise (S/N) ratio can be set for the
squelch. If the squelch is activated, the RX audio output is muted until an
RF receive signal with a sufficient S/N ratio is applied.
The S/N threshold can be set in a range between 6 dB and 20 dB.
Note: The thresholds are defined for S/N. The corresponding value of
SINAD will be 2 dB higher (SINAD 12 dB value corresponds with S/N
10 dB value).
The RSSI threshold is based on the received signal level at the receiver's
input. The RSSI threshold can be set in a range between 1 μV and 50 μV.
This parameter refers to opening the squelch in presence of a carrier which
is higher than –85 dBm, even if other squelch criteria like S+N/N of the
audio signal are not met.
Note: If the parameter is enabled and the input level is above –85 dBm,
the other squelch settings S/N Squelch Threshold, RSSI Squelch
Threshold and S/N RSSI Logical Operation are insignificant.
It is possible to combine the S/N-squelch and RSSI-squelch. By default
both mechanisms are "OR" conjunct. The squelch opens the audio path if
only one condition is fulfilled. In case of the "AND" conjunction both
thresholds must be exceeded in order to open the audio path.
Note: For offset reception it is recommended to configure the conjunction
type to "OR".
Note: If the "AND" conjunction type is selected, the squelch attack time
can be longer for levels above the RSSI Squelch Threshold than in "OR"
conjunction type. If the "OR" conjunction type is selected for input signals
below the RSSI Squelch Threshold, the attack time can be longer.
3.14
Configuring with the R&S ZS 4200