NF FRA5097, Instruction Manual

Page: 26 / 192

1.4 Principle of operation
FRA5097 1-10
Changing oscillator frequency
Changing preamplifier gain
Performing measurement and analysis
Changing oscillator frequency
Changing preamplifier gain
Performing measurement and analysis
ω
1
V1
(ω1)
V2
(ω1)
ω
2
Changing oscillator frequency ω
3
V1
(ω2)
V2
(ω2)
Fig. 1-2 Frequency sweep measurement with FRA
In addition, the discrete Fourier transform used for the FRA analysis has the following features:
z The discrete Fourier transform itself has a steep band-pass characteristic, and therefore,
the effect of noise and harmonics will be reduced.
z Measurement can be made within the time period that corresponds to the period of the
analysis frequency, since only about one (1) second is needed to measure the amplitude
and phase for 1 Hz.
z The freedom of setting measurement frequencies (frequency sweep density) is large, that
is, selection between linear/logarithmic sweep is possible, the number of measurement
points per sweep can be set as you like, etc.