NOAA Satellite Image Reception

Did you ever think : How does my phone know what the weather is going to be like? Well, the answer to that question is pretty simple : It gets images from low earth orbit satellites which it then uses to predict what the weather is going to be like.

Now, for some time I knew that these image signals can be intercepted and an image can be decoded (courtesy to The Though Emporium : ), however I kept putting this project of because I simply had other priorities at that time. This summer though, I heard that the NOAA 15 and NOAA 19 weather satellites were being decommissioned, in August of 2025, so just like that, this project jumped at the top of my priorities list :)

For signal reception I chose a cross dipole antenna as it is non directional, simple to build and can have great results. I found various sources of how to build one, though none went into great detail, so I will condense a few things that I trouble-shot myself, and I consider important :

-All coaxial center conductors connect to upward pointing ends of the 4 dipoles.

-The antenna doesn’t have to be very high up. Mine worked best when I was crouched near the ground, holding it.

-This antenna works only after the satellite has risen above 20-30 degrees.

For signal reception and processing I followed a similar route to many other hobbyists, by using a USB SDR like RTL-SDR that can go down to very low sampling rates. HACK RF does NOT work !!! It has a minimum sampling rate of 8 MHz which is too high as it introduces too much noise. When it comes to the software, I had a lot of headaches trying to make this work with SDR++, but to this day, I have no idea why, but signal quality is awful on it. SDR Sharp is the way to go, and it offers quite a good result too!

To decode the image, save yourself the trouble of trying different softwares and just use WX to IMG or SatDump. They both work great.

In the end I managed to capture roughly 2 dozen high quality images, of which I will post a few below.