After several initial targeted searches, I am still at a loss about one thing that needs confirmation and that no google search seems to be able to uncover. In the US, no significant RF communications can take place without being licensed by the FCC or licensed by Congress directly. Every radio service is made legal only through an FCC section of rules based on laws that govern the given radio service. Even the radio services that do not require anyone to obtain a license to use that service, have a set of rules that govern the use of those radio emissions. If no license is required of the user and the service also does not require a license to be obtained by some business, then that radio service is still licensed. It is licensed by statute for use by everyone. With all of this said, which set of FCC rules govern the use of the LoRa systems? Every search result I’ve been able to get has yielded only answers that say something like “LoRa uses the unlicensed bands”. This is an extremely ignorant answer. After twenty search results in a row repeat this ignorance, you want to pull your hair out. There are no unlicensed bands in the US that are legal for use. Some bands are licensed for use by everyone, by statute. But there are no actual unlicensed bands available for use. If there is no license, that means that no one is allowed to use it. This still doesn’t tell us under which section of the FCC rules the LoRa systems are governed. My guess is FCC part 15. But that is only a guess and may be wrong. This matters greatly because you can’t even play the game intelligently if you don’t know the rules. You need the applicable FCC rule book. Try reading FCC part 80, part 90, part 97, or part 15 (all easy to find from a simple search). Has anyone else here found the applicable rules, statutes, that define the limits of LoRa systems? The chip manufacturer’s datasheets are far to vague. An output power of 4.2mA with -22dbm says little about the actual output power and still says nothing about what the legal limits to output power are.
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