Hello Bertus,Hello Vladimir,
Long time no see.
Welcome back.
For 45 degrees you can multiply the frequency with 8 and decode the wanted signals.
The multiplication can be done using a PLL.
Greetings,
Bertus
Unnhhh, I think that's going to yield 90 degrees phase shift, not 45.You can also turn the signal into a triangle wave with a integrator (which moves it 90°), then feed it to a comparator. Its not TTL, but it can feed TTL. It is definitely analog, but simple.