Why is the lowpass-filter coming right after the local oscillator when mixing an RF? In the book, instead of having a band- or lowpass-filter before mixing, it's coming right after mixing, which makes sense, considering there's gonna be a high-frequency component, which has to be filtered out.

But the lowpass-filter is called RF Image Rejection Filter, which irritates me, since that would be a band-pass instead and not something done after, but before mixing.

Curiously, afterwards there's an IF Band Selection Filter, which is meant to filter images?
Today I received an answer from the authors of the book. It turns out that figure 1.7a was wrong, and they sent me the updated one.

The corrected diagram will be added in this Summer's update!