[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Discuss-gnuradio] GOES LRIT???
From: |
Patrik Tast |
Subject: |
Re: [Discuss-gnuradio] GOES LRIT??? |
Date: |
Fri, 25 Oct 2013 18:14:53 +0300 |
On Fri, 2013-10-25 at 18:13 +0300, Patrik Tast wrote:
> Yeah, use a RTL-dongle and you could also use a $5 TV-inline amplifier
> (or 2x if you have a long line). TV-inline amplifier:s are noisy but who
> cares in your case, the GOES signal is strong at you location. You can
> find one at ebay or here
> http://www.sadoun.com/Sat/Order/Switches/inline_amplifier.htm
>
>
> Patrik
>
>
>
>
> On Fri, 2013-10-25 at 10:31 -0400, Raydel Abreu (CM2ESP) wrote:
> > Hi Patrick,
> >
> >
> > Thanks for the help. A full-disk is a nice start from scratch, and
> > perhaps later going better. I have an RTL-SDR dongle with a R820T
> > tuner, my idea is to eventually receive data with it, but it is a work
> > in progress. The dish and the LNA should be ready by January.
> >
> >
> > I live in Cuba, but I have a friend in Argentina who has a dish, a LNA
> > and a RTLSDR dongle working right now. I will ask him for record a WAV
> > file containing I/Q data from the dongle and then try here at my home
> > for demodulate his signal. If we had success, that will be excellent.
> >
> >
> > I have to wait until my ground station is complete, here in Cuba there
> > are no specialized stores for that so all the equipment has to be
> > homebrew. I am working on the dish and its feed and a friend in
> > Croatia sent me a 1500 MHz LNA which I have to try to re-tune to 1700,
> > when the postal package arrives next month... I have my fingers cross
> > hoping to have all ready by January.
> >
> >
> > So far I have only obtain APT imagery, but I guess APT will not be
> > active too long, so GOES seems to be the best choice...
> >
> >
> > Best regards,
> >
> >
> > Raydel
> >
> >
> > 2013/10/25 Patrik Tast <address@hidden>
> > 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
> >
>