Many times, the system phase noise is given with an internal reference oscillator or a test oscillator
used as a reference for measurement purposes.
An unusual feature of this test oscillator
is that the power supply is a low frequency square-wave.
Single-element-controlled sinusoidal oscillators find numerous applications in communication, control systems, signal processing, instrumentation, and measurement systems as test oscillators
or signal generators [7-11].
These phase-locked frequency synthesizers are ideally suited for use as low cost solutions for broadband test oscillators
. Supplied as fixed-frequency or serially-programmable precision phase-locked oscillators, the synthesizers are designed to cover the frequency range from 50 MHz to 12 GHz in up-to-octave bandwidths.