General Description
R&S
®
CMW-KM645
12
User Manual 1173.9740.02 ─ 04
Fig. 3-3: FM Stereo Radio: RF Carrier Results
The table contains the following results:
●
Carrier Power:
Absolute power of the RF signal in dBm. The carrier power is mea-
sured in a 500 kHz IF bandwidth.
●
Carrier Freq. Error:
Difference between the measured RF frequency and the
selected center frequency of the analyzer ("RF Settings > Frequency"), which is
assumed to be the rated frequency of the RF channel.
●
Multiplex Deviation,
±
Peak / 2:
Frequency deviation of the RF signal due to the
composite multiplex signal (baseband signal, including the mono and stereo sig-
nals and the pilot; see
), half of the peak-to-peak value of the frequency
deviation.
The multiplex deviation is measured directly after the FM demodulator, before sep-
aration of the different baseband signal contributions; see
.
●
Multiplex Deviation, + Peak:
Maximum frequency deviation due to the baseband
signal relative to the rated RF frequency.
●
Multiplex Deviation,
–
Peak:
Minimum frequency deviation due to the baseband
signal relative to the rated RF frequency.
●
Multiplex Deviation, RMS:
RMS average of the multiplex deviation over an appro-
priate time interval (moving average). If the baseband signal consists of a single
sine wave (e.g., the pilot tone with no mono and stereo signal contributions added),
the RMS multiplex deviation corresponds to the "Multiplex Deviation,
±
Peak / 2"
divided by the square root of 2.
For an unmodulated carrier, the multiplex deviation is close to zero.
As shown below the peak-to-peak frequency deviation is independent of a possible
carrier frequency error.
Fig. 3-4: Definition of peak-to peak frequency error
Measurement Results
深圳德标仪器
135-1095-0799
