Re: [Discuss-gnuradio] FHSS

[Eric Blossom]

On Tue, Jul 05, 2005 at 04:45:06AM -0400, Joshua Davis wrote:
> 
>   Hi.  First time caller.

Welcome!

> Are any FHSS (frequency hopping spread
> spectrum) options avail in software for gnuradio/USRP?  Or do I need to
> create one by hand?  If someone else has implemented this, can someone
> provide a pointer to code, so that I can use their ideas?

We haven't implemented anything at this point, but we've given it
quite a bit of thought.  One of the questions that needs be answered
depending on your application/hardware, is would you be hopping by
controlling the RF front end, or are you hopping over a narrow enough
range of frequencies that we could do it all in software/FPGA?

There are of course the normal wide band / dynamic range issues if you
try to do the hopping all in software/FPGA, but it would be pretty
straight-forward.  You could also hop at a ridiculously high rate
since you don't have to wait for an analog PLL to settle.

It might we worth taking a look at the FM3TR spec for a starting
point.

http://mccoy.ucsf.edu/emondi/Public/FM3TR/FM3TR_Summary.html
http://www.computing.surrey.ac.uk/personal/pg/E.Willink/wdl/Fm3tr.html
http://www.sdrforum.org/MTGS/mtg_25_sep01/01_i_0056_v0_00_fm3tr_97_09_10_01.pdf


Eric

>    ----
>    Joshua Davis
>    Transient Infrastructure Security Solutions
> 

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