[Wormnet] http://www.edn.com/contents/images/245648.pdf

[Peter Steen]

Hi FOlks!

Some simple calculus:

The FIR and FFT algorithms I developed for the m68k ten years ago consumed 
roughly 80-900 clock cycles for one analysis of 300-4500 Hz band.

The VHDL chips above do 250 to maby 450 MHz.
Sample rate nessesary for quality will bring the megaherz value down
to somewhere /3 to /10, say worst case /10 -> we are now down to 25-45MHz 
signal input. Ok calculus is now needed, we use the same calculus like the old 
FIR FFT story ten years ago (it is still the same math needed and will be in 
ten thosand years to) speed is not slowed down directly by 80 to 900 clock 
cycles but almost, let say some improvment can be made and we are down to 80 
clocks as max -> now our signal is down to 312,5Khz - 600Khz.

It is goot for LW RF signals ! And it is not the ISM band.

Workaround allways exists, let say we use several chips in an array who deal 
with a narrow band, speed can be improved a lot. But still we will need to use 
many paralell channels, mixing down HF the classic way in stripes of bands to 
comfortable bandwith of some hundred kiloherz each..

Maby I am wrong, comments please...

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

> 
> I am working here with your assigment and hopefully I will show you some 
> good work.
> the thing mr Bear told me is that you might need to realise things in 
> paralellism.  Yet
> Its DSP related. I will find the answers and  howtos.  I remember the ting 
> My old friend did to
> me he locked me in and did not open the door until I had solved it, same 
> here...
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> ----- Original Message ----- 
> From: "Peter Steen" <peter.steen at ing-steen.se>
> To: "mIB" <marcel.bos at ing-steen.se>
> Cc: <wormnet at polarhome.com>
> Sent: Friday, December 09, 2005 4:05 PM
> Subject: Re: [Wormnet] http://www.edn.com/contents/images/245648.pdf
> 
> 
> > Dear Marcel!
> >
> > Limiting to 200MHz will cause all wormnet device to be unlawful!
> > The ISM band's are nowdays all over 433MHz! The 27MHz ISM band will be 
> > closed
> > in very near future as well as the 40MHz ISM band.
> >
> > Wormnet is NOT of concern to only PR radio entusiasts and Amateur radio
> > entusiasts.
> >
> > The first working principles of wormnet must therefore be proven to work 
> > with
> > ISM bands and existing chips.
> >
> > VHDL solutions must wait until technology has been proven in other radio
> > situations, which is has not yet been. I did not find any commersial
> > implementations of strait VHDL based radio. Althought many VHDL solutions 
> > used
> > as stick between motherboard chipsets in the PC world. There are 
> > alternates to
> > VHDL which work out of the box for RF.
> >
> > Did any of you look on the Maxim, nRF and Chipcon products ?
> >
> > Regards //
> >       //  Peter Steen
> >
> > Citerar mIB <marcel.bos at ing-steen.se>:
> >
> >> http://www.edn.com/contents/images/245648.pdf About the signalprocessing
> >> inside VHDL and more.
> >>
> >> I spoke to some swedish friends around here and if we can limit ourselfs 
> >> to
> >> about 200 mhz then it might
> >> work.
> >>
> >>
> >
> >
> >
> >
> > -------------------------------------------------
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> > 
> 
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