[mlyle]

> but excluding radio satellite they are mostly bellow 300 MHz...

The 70cm band (420-450MHz US) is heavily used. I'm sure cellular services would love it. On the other hand, it is a secondary allocation with other users (e.g. military radars) having priority.

The 23cm band is another secondary allocation, from 1240MHz to 1300MHz-- wide enough for 3 wifi channels. On the other hand, you'd have to kick out the radiolocation service, and it's not contiguous with a big block of channels to make it worthwhile.

Then above that amateur shares frequencies with some of wifi and then microwave frequencies that are so high that they are undesirable.

[arghwhat]

The 70cm band is just 30 MHz wide in the US. The point was that none of these other allocations are wide enough to be useful for things like WiFi, which is currently using up to 320 MHz channels and needing several of those channels to avoid clashing with other nearby networks.

[RF_Savage]

23cm is under fire in Europe to protect GNSS services from potential interference. Allowing unlicenced operation there is very unlikely to ever happen.

[ac29]

> 1240MHz to 1300MHz-- wide enough for 3 wifi channels

Wifi isn't necessarily a minimum of 20MHz. Wifi HaLow goes as low as 1 MHz.

[mlyle]

As in, something that happens to be called Wifi but is IOT focused and doesn't interoperate with normal consumer devices. It's not a wealth of spectrum in any case, and the fact that a lot of the radiolocation services are satellite based ... they're not going anywhere.