Communications Blockset

Analog Filter Design

The Analog Filter Design block filters high frequencies out of the signal coming from the phase detector. The block uses a lowpass Butterworth filter. You can use a higher order filter or another filter type to improve the stability of the synthesized signal.

In the steady state of the model, the amplitude of the block's output signal will be approximately constant, with a value of .5. This is the average value of the output from the phase detector.

Phase Detector

Gain Block