[time-nuts] WWVB BPSK Receiver Project? (fwd)

[Poul-Henning Kamp]

In message <20120317111119.9536107ebf82050fe14ee85c at kinali.ch>, Attila Kinali w
rites:
>On Sat, 17 Mar 2012 10:01:13 +0000

>Could you explain why? Yes, you need a higher BW for Loran-C,
>but the phase(f) function will give you only a distortion of
>the signal and a constant time delay in your signal recovery.
>But that shouldnt degrade the usefullness of the system.
>What am i missing here?

Either you need to characterize the exact behaviour of your filter
and build the necessary compensation for its phase/frequency behaviour
into your receiver, or you need a very flat filter (both freq+phase)
in order to reliably recognize the proper zero-crossing to track.

The more you disturb a Loran-C pulse, the more it just looks like
a bit of a sine-function, and the harder it is to lock on the right
zero-crossing.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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