[Sorry for the noobish question...]
I have a signal which is known to be generated by a process operating at some known rate $f$ Hz and the sampling rate is also know to be $K$ Hz. Now I do a periodogram of the signal and its first peak (aka fundamental frequency, right?) closely corresponds to $f$ - so I'm quite happy.
But now I want to estimate the amplitude and phase using a standard algorithm which I am taking from this good book (Algorithm 9.2). The snag is that there the frequency $f_{0}$ is supposed to satisfy $0 < f_{0} <\frac{1}{2}$ and I am at a loss as to how to convert my $f$ to Kay's $f_{0}$. I tried to take $f_{0}=\frac{f}{K}$ but got gibberish results.