User`s guide

Interpreting views (plots)
• FFT - Time amplitude vs. frequency content of jitter
• Summary - View data in a text format and save user notes
FFT View
This is the FFT of the acquired data. This plot shows the spectral power density of the jitter component
frequencies from the carrier frequency to the Maximum Frequency entered in the options.
In the following plot example, a phase noise measurement is made on a clock signal with injected phase
noise.
The signal source is a Marconi 2041 low noise signal generator. The signal has a carrier frequency of f
0
= 1 GHz. The carrier is frequency modulated with white noise and deviation of ∆
f = 50 kHz.
The bright magenta line is the phase noise measurement of the carrier with noise added. The dim
magenta line is the same measurement without noise and corresponds to the ~1/
f noise floor of the
instrument.
The x-axis shows the frequency offset from the carrier.
The y-axis shows the measured phase noise.
Section 4 - GigaView © WAVECREST Corporation 2005
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