A second-order PLL is implemented with a non ideal loop filter: H(s) = (s+a)/(s+b) in which b > 0 is very small.
(a) Applying small-signal analysis, determine the transfer function between Oe(s) and Oi(s).
(b) Find the steady state PLL phase error for an incoming phase Oi(t) = (w0 - wc)t + a0