Goes lrit?

Hello,

Is there any GOES LRIT decoder available under Linux and GNU Radio with
support for USRP or RTL-SDR. In case there is only USRP compatibility,
perhaps with the GRC file freely available it can be attempted to be
converted for RTL-SDR?

I have found some tools but only for POES HRPT…

Thanks,

Raydel

Raydel,
There was included in Gnuradio3.3 an example called usrp_rx_lrit which
has since I assume been depreciated. I have never actually used it. so I
can’t comment on how well it might have worked. It is attached here for
your reference, though I suspect it will be a major effort to get it to
work with a modern version of gnu radio.

-Ian

Hi,

See https://github.com/mbsat/gr-poes-weather/tree/master/apps/GOES/gui
You need to upgrade the code to work with latest GR (to use cmake and
stuff)

To decode frames into images you need to use the RICE algorithm.

Patrik

Hello Ian and all,

Thanks for the attached files, i tested it but when opening it says that
some blocks are not defined, a costas loop in one case and I don’t
remember
the other one…

After browsing a little bit on the GNU Radio website I found a folder
that
includes that files, perhaps, downloading the entire folder and building
it
would fix the missing files error.

Thanks!!!

Raydel

2013/10/25 Ian B. [email protected]

Hi Rydel,

Right, you will first get CCSDS frames (bpsk-demodulated) let us call
that file lrit-frames.dat. To create images from the frames
(lrit-frames.dat) we need to unpack the data (lrit-frames.dat) using the
RICE algorithm to a new file say goes-13-lrit-frames.lrit. Since the
data rate is low we could rice-decode the frames (10 frames/earth disk)
on the fly, of course.

The (NASA) RICE algorithm seems to be fairly easy BUT I haven’t bothered
to try since the result (full-disk) ain’t that valuable for weather.
You’ll get nice images of Tellus, that’s 4 sure.

The RICE lib from NOAA is found here
http://www.noaasis.noaa.gov/LRIT/software.html It doesn’t link (on
linus), we’ve asked if they could release source-code so we could make
it cross-platform (last year)…

We will support you if you want to have a go. We have antennas standing
by at LA (Los Alamitos)

Patrik

Inorder to port it to GR the C++ code is needed (where all the fiddling
is done).
Can you give us a link?

Patrik

Patrick,

Thanks for the link!!! I have visited your repository before, but I
failed
to dig deeper, that’s why I didn’t found the GOES I believed it was only
for HRPT, that’s a great opportunity, I will try to build it.

Quick question, you mention I need to do RICE for obtaining images, so
if I
understand correct your application produces the frame files, a
(dot)lrit
file if I am correct? If that’s the case I can use your program for the
receiving chain, dump the lrit files into a shared folder and then
processing the images with compatibles windows programs I am familiar
too.
Am I correct?

Thanks!

Raydel

2013/10/25 Patrik T. [email protected]

This forum is not affiliated to the Ruby language, Ruby on Rails framework, nor any Ruby applications discussed here.

| Privacy Policy | Terms of Service | Remote Ruby Jobs