[amsat-bb] NOAA Weather Satellite receiver

[Iain Young, G7III]

Hi,

I used a Funcube Dongle and gnuradio. You do need the 40 (34)kHz bw.
Google for OZ9AEC, Gnuradio, NOAA.

Alex has done it in gnuradio. I have also done it in gnuradio [to be
honest most of it was "borrowed" from Alex]

See http://hal.g7iii.net/POES/FlowGraphs/POES_Live_Decode_Annotated.png

If you patch in a resampler (to 11.025kHz) between the FM Demod and
Audio sink blocks, you can send that to an ALSA loopback sound device,
and connect wxtoimg to the other end.

See (unannotated, and with extra debug, dual output so I could compare,
and other features):

http://hal.g7iii.net/POES/FlowGraphs/POES_Live_WXtoIMG.grc.png

Plenty of received pictures at http://hal.g7iii.net/POES/


Iain

On 05/12/14 22:29, jkelly wrote:
> I believe the bandwidth is less - but due to doppler they spec a 40khz
> bandpass so
> the 34khz signal can slide within the 40khz receiver.
>
> This link might be helpful:
>
> http://en.wikipedia.org/wiki/Automatic_Picture_Transmission
>
> Jeff
> K2SDR
>
> http://wx.k2sdr.com
>
>
>
> On 12/5/2014 4:34, Rupesh Lad wrote:
>> Hello all;
>>
>> I am an undergraduate Engineering student and a SWL. I have tracked many
>> Amateur satellites from COEP Ground station, VU2COE.
>>
>> I want to Home brew a NOAA satellite image receiver as my academic
>> project.
>> I will be using WXtoImg to decode the image transmitted by NOAA satellite
>> on APT frequency. So the task for me is to get the audio frequency
>> output.
>>
>> Literature says that NOAA satellites transmit a signal of 40 kHz
>> bandwidth.
>> I have also observed the spectrum on Spectrum analyzer using my antenna.
>> Want to know whether this is only RF bandwidth? and if it is so, then
>> what
>> is IF bandwidth of such signals?
>>
>> Can anyone help us in designing the receiver?
>>
>>
>
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