Signal Analyzer

bsw TestSystems & Consulting AG (bsw)

The simplest way to measure the phase noise is to compare the Device-Under-Test (DUT) to the source of a spectrum analyzer. With the SA set at the same frequency as the OUT, you see the sum of the SA's and DUT's sideband-power spectrum on the SA display. It is a simple and straight forward method well suited for free running VCO's where the SA is easily an order better.You can improve on this method by establishing a Phase Lock (PLL) between the DUT and the Local Oscillator and create a zero-IF or base-band spectrum analyzer system.