[Wormnet] filter design

[Peter Steen]

Hello folks!

Drop the bandpass fixation!

We have to analyze several hundreds of megahertz in paralell, not sweep it is 
way to slow process, you have to stay to long in each frequecy in order to 
detect carrier and such, at least 5 or ten radians. This way lower frequencies 
is wery slow and higher frequencies faster and faster the higher you get. It 
will take seconds or more to sweep the spectra in classic ways and you will also
miss all non fix carrier transmissions.

Bit deep is exactly in correspondence with the weakest signal you want to be 
able detect. Modern recievers can catch signals as low as -105 dBm and still 
you recieve many megabits per second. It is easy to do a small calculation
and see how many bits needed.

Also how should sweeping filter design deal with hopping frequency transmitters 
and direct sequency transmitters which become more and more popular.

No, drop the sweep filters they will not work here.

Regards //
       //  Peter Steen

Citerar mIB <marcel.bos at ing-steen.se>:

>  
> I am still figuring on this sweaping filter for the digital spectrum
> analyser.  I have found by mind that the bandpasfilter must be exact
> one wavelength of the given frequency one listens to so that the data from
> this given frequency can be sampled and stored.
> 
> Whats unclear is the bit deep for the A/D converter for the best silent
> sampling enviroument.. 
> 
> 
> 
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> 




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