Hailstorm in 12GHz

Yesterday, there was a big hailstorm in my town. During the storm, I rushed to the radio shack to see if this produced any effects in my Ku-band satellite receiver. This is a 95cm dish pointing to the 26ºE geostationary orbital position, and it will be used to receive Es'hail-2 in the future. In the image below, you can see that the difference is huge.

11699MHz H pol, during a hailstorm (above) and just after the storm (below)
11699MHz H pol, during a hail storm (above) and just after the storm (below)

In the waterfall, you can see several beacons from broadcast satellites. It is clear that during the hailstorm the noise floor was much higher. In fact, 2.5dB higher. This is probably caused by scattering of DVB-S signals from satellites in other orbital positions, scattering of thermal ground noise, or a combination of both. Also, although it is not easy to see in the waterfall, the beacons of the satellites where weaker during the hailstorm. For instance, the beacon of BADR-5 was 0.9dB weaker, due to the increased attenuation caused by hail.

These differences may not seem large, but in fact they are. I have a cheap DVB-S2 decoder connected to the system. It usually receives fine several channels from the BADR satellites (on some other channels, the signal is not good enough, apparently). However, during the hailstorm, this receiver couldn't even get a lock on the DVB signal.

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