Lambda SR1, Руководство по эксплуатации, Страница: 166 / 317

SR1 Operation Manual 166
© 2014 Stanford Research Systems
Harmonic
Distortion Bins, ( A/
B)
The vector containing only the bins that represent harmonics of tones present in
the generator signal.
IMD Distortion
Bins, (A/B)
The vector containing intermodulation products of the tones up to the order
specified on the analyzer panel. 2nd order IMD products, for instance, fall at
frequencies equal to f
1
±f
2
where f
1
and f
2
are tones in the generator signal. Note
that not all IMD products of a given order may fall within the analysis range.
Noise Bins (A/B)
This vector contains bins that contain no tones or distortion products. If "Noise
Analysis" is enabled this vector will contain all the odd bins in the analyzer FFT.
If noise analysis is not enabled the analyzer examines each bin and only
includes bins in the noise vector that contain no tone, harmonic of a tone, or IMD
product of tones.
Total Distortion
Bins (A/B)
This vector measurement is only active when "Noise Analysis" is selected. For
each non-tone bin pair, the power in the odd bin (noise) is subtracted from the
power in the corresponding even bin (noise+distortion). The resulting vector is a
good indicator of the total distortion at each frequency.
Frequency
Response Mag.(A/
B)
The vector containing the ratio of the received amplitudes at the tone locations
relative to the generated tone amplitudes.
Frequency
Response Phase
(A/B)
The vector containing the phase at the tone locations relative to the phase of
each generated tone. For the phase measurement to be meaningful several
conditions must be met. First the MTA must be running in synchronous mode.
Second, the analyzer must be triggered, so that the analyzer's FFT time record
maintains a consistent position with respect to the generator signal. The
frequency response phase is calibrated only when using the generator trigger
source. Be sure to set the trigger source on the "Trigger" tab of the analyzer to
"Generator" and set the "Generator Trigger Source" to either Analog or Digital
depending on which generator is being used.
THD+N vs. Freq. (A/
B)
The vector of the ratios of the sum of the harmonics for each tone and the noise
amplitude to the received amplitude at the tone frequency. For this measurement
it useful to select a tone frequency distribution such as "log prime" or "linear
prime" so that harmonics of different tones do not fall on the same frequencies.
THD vs. Freq (A/B)
The vector of the ratios of the sum of the harmonics amplitudes for each tone to
the received amplitude at the tone frequency. For this measurement it useful to
select a tone frequency distribution such as "log prime" or "linear prime" so that
harmonics of different tones do not fall on the same frequencies.
IMD vs. Freq (A/B)
The vector of the ratios of the sum of all IMD products involving a given tone to the
received tone amplitude at the tone frequency.
Crosstalk (A/B)
This measurement is only active when the stereo mode is enabled on the
Multitone Configuration Panel since it relies on tones being present at different
frequencies for the two channels. The Crosstalk vector is the ratio of received
amplitudes in bins that do not have tones in the measurement channel to the
amplitudes of corresponding bins in the other channel that do have tones.