Anritsu Field Master MS2070A Measurement Manual page 118

3-21 AM/FM Modulation Measurement (Option 509) Spectrum Analyzer Measurements
3-21 AM/FM Modulation Measurement (Option 509)
The AM/FM modulation measurement evaluates the quality of the baseband signal retrieved from the
modulated signal. The graphical representation of the baseband signal indicates the pattern of modulation
depth/deviation versus frequency and time.
The AM/FM audio provides quantitative measurements of analog radio transmitters using amplitude and
frequency modulation. In addition to numeric results, AM/FM modulation measurement provides a new audio
spectrum display and audio demodulated signal vs time (oscilloscope) display.
The ALL MEASUREMENTS view consists of the graphical representations of AUDIO SPECTRUM, AUDIO
TIME DOMAIN, RF SPECTRUM in addition to AUDIO RESULTS table.
The audio spectrum displays the frequency spectrum of the demodulated audio signal.
The audio time domain provides an oscilloscope style display of the demodulated audio signal in amplitude
versus time.
The RF spectrum display is the standard RF spectrum of the modulated carrier.
The audio results table consists of several numerical measurements such as SINAD (Signal-to-Noise and
Distortion) ratio, THD (Total Harmonic Distortion), depth and deviation.
The ALL MEASUREMENTS view is available only if Option 509 is installed. See Figure 3-81.
To select All Measurements view navigate to MEASURE>MEASUREMENT>AM/FM AUDIO>VIEW>ALL
MEASUREMENTS.
6
5
1 2 3
4
7
8
9
Figure 3-81. AM/FM Audio – All Measurements View
3-100 PN: 10580-00447 Rev. E Spectrum Analyzer MG