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Frequency divider

Started by sasilion January 18, 2003
Hi Guys,

My question has something to do with frequency multiplier and
divider in a PLL. For example, before a QPSK is fed into a PLL, i
have to pass the signal through a 4th power device and bandpass it.
I could do this by muliplying 4 times. However, i am not sure how to
divide the estimated carrier coming out from the PLL by 4 times.

Does anyone knows how to implement this frequency divider?

Thanks.



Hi,

You dont divide the carrier by 4 and then estimate it. Instead you estimate the
new carrier (which is 4 times the original carrier) and then divide the
estimate by 4.
For e.g.:
If your original carrier was Fc, after the frequency multiplier it will be
4*Fc. You estimate F' (~= 4*Fc) from this signal and F'/4 will be your estimate
for Fc.

-priyank

--- "sasilion <>" <> wrote:
> Hi Guys,
>
> My question has something to do with frequency multiplier and
> divider in a PLL. For example, before a QPSK is fed into a PLL, i
> have to pass the signal through a 4th power device and bandpass it.
> I could do this by muliplying 4 times. However, i am not sure how to
> divide the estimated carrier coming out from the PLL by 4 times.
>
> Does anyone knows how to implement this frequency divider?
>
> Thanks. >


__________________________________________________



Hi Priyank,

You mention something about estimating F'(~Oc) and then F'/4
will be my estimated carrier. My problem is how to implement this F'/4

Thanks.
--- In , Priyank Saxena <spriyank@y...> wrote:
> Hi,
>
> You dont divide the carrier by 4 and then estimate it. Instead you
estimate the
> new carrier (which is 4 times the original carrier) and then divide
the
> estimate by 4.
> For e.g.:
> If your original carrier was Fc, after the frequency multiplier it
will be
> 4*Fc. You estimate F' (~= 4*Fc) from this signal and F'/4 will be
your estimate
> for Fc.
>
> -priyank
>
> --- "sasilion <gundamzerowing9@y...>" <gundamzerowing9@y...> wrote:
> > Hi Guys,
> >
> > My question has something to do with frequency multiplier and
> > divider in a PLL. For example, before a QPSK is fed into a PLL, i
> > have to pass the signal through a 4th power device and bandpass
it.
> > I could do this by muliplying 4 times. However, i am not sure how
to
> > divide the estimated carrier coming out from the PLL by 4 times.
> >
> > Does anyone knows how to implement this frequency divider?
> >
> > Thanks.
> >
> >
> > __________________________________________________
>