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blosxom


Contact/Impressum

       
Thu, 03 Mar 2005
USRP has finally arrived - what next?

The regular reader of this blog already knows what the USRP is. The infrequent reader is referred to this blog entry.

So it has finally arrived, although I really don't have too much time of playing with it at the moment. I guess I'll do some basic functionality tests and then have to put it aside for some time.

One of the important issues remains the lack of readily available RF frontends. With the BasicRX frontend, you can basically sample amplified signals of up to 32MHz bandwidth below 200MHz.

I've investigated a lot of options with regard to RF frontends, and none of them is really promising:

  • A commercially available 20-3000Mhz tuner/down-converter WiNRADIO WR-G526e. That's what we all want. Unfortunately horribly expensive, I've read USD6k somewhere :(
  • Using a commercially available radio scanner with 10.7MHz IF output. This sounds like a good idea. The problem is that most of them seem to have ridiculously small IF bandwidths:
    • Yaesu VR-5000 (+- 100kHz IF bandwidth): ~ 500-600 EUR
    • AOR AR3000A (IF bandwith unknown): 780 EUR
    • AOR AR8600MK2 (IF bandwith +- 2 MHz): 710 EUR
    • AOR AR5000A (IF bandwith +- 5MHz): 1600EUR
    So if you want to go for high-bandwith signals such as DVB or 802.11, only the AR5000A would be usable... again quite pricey.
  • Using a DVB-{T,S,C} tuner to build your own USRP RF frontend. That sounds reasonably priced, but requires quite some amount of work. Issues include
    • Obtaining tuner samples from vendors like Sharp or Microtune
    • Designing the support circuitry (voltages, matching)
    • Writing software for tuning (mostly i2c bit banging)
    Possible Tuner Modules I've found so far

[ /linux/gnuradio | permanent link ]

Returned from FOSDEM

FOSDEM was a huge success, met lots of interesting developers working in various different areas. The conference facilities seemed more crowded than at any other conference - probably due to small hallways and really cold weather outside, combined with the lack for space where people could just sit and chill out.

One dinner with Alan Cox, one with the gnomemeeting crew and another one I ended up sitting next to the author of squashfs :)

I was a bit disappointed that Richard Stallman (although present at the event, delivering two speeches himself) did not attend my closing talk on GPL enforcement. Maybe he was already travelling home at that point, or he's really not that much interested in my first-hand experience on enforcing 'his' license.

Also, I got rid of the last batch of netfilter t-shirts, saving me from finding further excuses why I am not shipping them anymore ;) Also, this means we can now head for a new logo (stating Linux 2.6 instead of 2.4) and probably even black shirts, since I don't wear white shirts anyway ;)

[ /linux/conferences | permanent link ]

ctapi-CyberJack Version 2.0.8 has been released

I've made a new release of the ctapi-cyberjack driver for REINER-SCT. Until they put it up on their homepage, interested parties can always grab the latest source and rpms.

[ /linux/cyberjack | permanent link ]