I was watching some PLL video lectures by Professor Elad Alon, and he explains why intuitively the jitter transfer function of the loop filter to the PLL output has a bandpass characteristic. He says that when you inject noise at the output of the loop filter, because there is an integration function before it (in the loop filter), any noise at DC is thrown away. I was not quite clear about this because while I understand an integrator's response to noise before it, what impact does an integrator have on a noise source injected at its output? Or am I interpreting this completely wrong?
The time stamp for this statement is here: http://www.infocobuild.com/education/audio-video-courses/electronics/EE290C-Spring2011-Berkeley/lecture-17.html at 35:35 minutes.
Also, at another point, he says the VCO's transfer function has a high-pass characteristic, because with the pole at 0, the infinite DC gain would cause any noise injected into it to go to zero. I am not quite sure I understand how this works-- is it because infinite DC gain of an integrator just mean that there is no steady state error at DC, and this is an analog of no jitter ? Sorry if these are stupid questions, it's been a long time since I started studying PLLs and I am quite rusty.