I want to learn more about PLL but I'm stuck with the concept of "rate of change of phase" which is said that is equal to frequency. At the moment I'm very ignorant at the topic so I need to understand this mathematical foundation before I can proceed.
I couldn't decide whether this is a math question or can also belong here since its about analog signal. Is there an easy way to relate the phase to frequency? How is frequency equal to the rate of change of phase and isn't the phase of a sine fixed always given a sinusoid? So is this about signals where their phases changing by time? I could find any easy derivation on the topic.
Best Answer
A sine wave can have a relative phase to another sine of the same frequency or be described as having a specific phase at time zero. This is not the type of phase they are discussing here.
They are referring to an instantaneous phase. The frequency is the derivative of the phase, ω = dθ / dt. All units are rads, of course.