gr-ais with osmosdr

Nick Foster nick at ettus.com
Mon Aug 6 22:20:30 UTC 2012


Looking forward to seeing it. Would be very nice to have ACARS data
alongside ADS-B.

--n

On Mon, Aug 6, 2012 at 3:05 PM, <friedtj at free.fr> wrote:

> not sure what "I've been doing gr-air-modes development in anticipation of
> our ..." means,
> but since ACARS was being discussed as an addition to gr-air-modes, please
> let me announce that I am
> about to complete an ACARS-decoding block which was quite well tested on
> the rtl-sdr.
>
> JM
>
> ----- Mail original -----
> De: "Nick Foster" <nick at ettus.com>
> À: "Christian Gagneraud" <chris at techworks.ie>
> Cc: osmocom-sdr at lists.osmocom.org
> Envoyé: Dimanche 5 Août 2012 17:13:14
> Objet: Re: gr-ais with osmosdr
>
>
> On Sun, Aug 5, 2012 at 11:45 AM, Christian Gagneraud < chris at techworks.ie> wrote:
>
>
> Hi there,
>
> I saw a message in the July archive (I wasn't subscribed yet at that date)
> about updating gr-ais with osmosdr support.
> I was working on the same thing recently, so i decided to publish my fixes
> on top of Antoine's one.
> The result can be found here:
> https://github.com/chgans/gr- ais
>
> I got it working with both an FCD and an RTL:
> ais_rx.py --rate 96e3 --gain 30 --error -17 -d -D fcd=0
> ais_rx.py --rate 1024e3 --gain 30 --error -110 -d -D rtl=0
>
>
>
> Thanks for doing this. I haven't been looking at gr-ais lately as I've
> been doing gr-air-modes development in anticipation of our DefCon talk. Now
> that that's over, I'll have some time to integrate these changes and
> hopefully modernize a few things in gr-ais which I've been putting off.
>
>
>
> Strangely passing freq_err=XX parameter to the source (using -D), doesn't
> work, the use of --error is thus needed (which will do a set_freq_corr()).
>
> Antoine, if you want sample file, just let me know.
>
> Nick, are you willing to integrate these changing back in gr-ais, Apart
> from the added automatic decimation filter, the changes are not intrusive
> at all.
>
>
>
> Yep, I'll pull it back in. I'm also going to need your help vetting the
> changes against the FCD, as I don't have one. I do have an RTL dongle I can
> do some testing with. Have you had much success with AIS on RTL?
>
>
> --n
>
>
>
>
>
> The default settings for UHD are 256Khz sampling with decimation filter 4,
> with this change, the decimation is one when using FCD (96KHz fixed
> frequency) and 16 for RTL when used at 1.024MHz (this was the minimum
> working frequency for me).
> Or maybe would you prefer to allow the user to set it manually, and use
> this technique as a fall back only.
>
> Please let me know what you guys think.
>
> Thx,
> Chris
>
> --
> Christian Gagneraud,
> Embedded systems engineer.
> Techworks Marine
> 1 Harbour road
> Dun Laoghaire
> Co. Dublin
> Ireland
> Tel: + 353 (0) 1 236 5990
> Web: http://www.techworks.ie/
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/osmocom-sdr/attachments/20120806/ea2d2d1a/attachment.html>


More information about the osmocom-sdr mailing list