That's cool.
Reminds me that scientists can use GPS to track earthquakes indirectly as it is interacting with the ionosphere: https://link.springer.com/article/10.1186/s40623-025-02211-y
Reminds me that scientists can use GPS to track earthquakes indirectly as it is interacting with the ionosphere: https://link.springer.com/article/10.1186/s40623-025-02211-y
This way you can - for example - track water height of a river next to a station. You basically receive the direct GNSS signal and the reflected one. Then do magic math.
Due to the low orbit of the GPS/Galileo/etc. satellites the reflection is basically "scanning" over the area of interest with an ultra precise signal.
It doesn't require super-cooled radio stuff and can be done with off-the-shelf-gear.