Comment by ansible

> What would be the best band for this kind of infrastructure? ( Disregarding any existing FCC licenses )

The frequency bands that have been licensed for cellular infrastructure.

Its all a trade-off. Higher frequencies get you better data bandwidth, but require more power and get attenuated more by stuff (buildings, trees). Lower frequencies get you much better range for a given power level and better building penetration, but lower data bandwidth.

Exceptions to this are the "crap" bands, like 2.4GHz and 60GHz. Microwave ovens (which are great interferers, BTW) use 2.4GHz because it is absorbed by water. Great for heating your food. No so great trying to transmit data in an outdoor environment with rain and fog.

60GHz gets absorbed by the oxygen in the atmosphere, so that's another band that's only good for very short ranges.

The bands the cellular carriers have now are a good trade-off between power requirements, data bandwidth, and other issues (like absorption). The ISM bands exist basically because nobody would pay to use them.