Why do satellite frequencies overlap with Wi-Fi?

In the SatNOGS DB I just saw that while there are a great deal of satellites that transmit in the 2200-2300 MHz range, there are even more in the 2400-2435 MHz range - overlapping Wi-Fi channels 1-7! Why in the world would anyone place those to - more or less mutually exclusive - services in the same frequency range? It would explain the immense levels of noise I’m experiencing in that band, but why place satellites there in the first place?

Microwave ovens, RC cars, RC boats, RC planes us that part of the spectrum as well. As I understand it, it is another one of those bands which are unregulated do as you like bands. Perhaps someone can offer a better explanation and educate both of us.

There also appear to be many more satellites using amateur band frequencies while providing no benefit to the amateur community. Who knows where this will all end up?

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Does it matter? Are weak 2.4GHz satellite signals likely to penetrate in to buildings? Most people have difficulty when their router is in the room next door :slight_smile: Likewise, is wifi that much of a problem to highly directional dishes that are outdoors?

Lots of 2.4GHz ISM band stuff is supposed to be spread-spectrum (DSSS/FHSS) so that it has some immunity to interference from other signals, as well.

Well, to be honest, I’m not sure. But if you look at this observation, for example, I strongly suspect that what you’re seeing in the waterfall is Wi-Fi, because my antenna is two meters away from my Wi-Fi access point. It’s a highly directional antenna (24 dBi) and it’s pointed towards local zenith, but I can’t shake the feeling that Wi-Fi is interfering anyway.

An antenna will have side lobes. Try switching to a different wifi channel. It looks like you are looking for a narrowband signal, so you you can move your wifi well away from the frequency you are looking at.

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