The big problem here is the spectrum, any spectrum, is being SOLD..
Spectrum use should come at a cost based on % of revenue or Profit paid back the people and used for common programs. Not a one time free where by then the private company owns it for all time
As for spectrum usage, I can only talk about my region, but I have been monitoring all of 70-1000 MHz at ~10 second intervals and storing the data since 2014. For periods of that I monitor 700-2700 MHz as well. The cell operators are not letting their bands sit idle as far as I can tell. It's nothing like what the top level comment thread implies re: ISM vs. Cell bands. If anything it's the reverse.
But that doesn't mean they should get this 6-7 GHz of new ISM spectrum the FCC returned the original owners: the people. They really, really shouldn't. And they shouldn't be allowed to operated unlicensed LTE in the ISM bands either.
It's a good case of dual-use of spectrum, though more spectrum should be made public either way.
For 70-1000 MHz it's just a homemade discone antenna hooked to an rtlsdr dongle running rtl_power. I have written a little bash script that automates calling heatmap.py to render the 30k pixel wide image, imgcnv to slice it into image tiles, and generate an PanoJS HTML page to display the tiles.