Originally Posted by
CKBA
Only partly true. The big problem is that 'legacy' systems (which today are probably anything older than a few months) are/were designed to deal the known frequencies/interference when they were built/first operated. New devices have expanded to frequencies close to these legacy systems and any minor out-of-bounds radiation can impact these older systems. The current battle beteen the FAA anf FCC is a case in point - related to the roll out of the 5G network and impacts on altimeters. FCC has recently refused to extend the roll out meaning that the airlines have to upgrade the older altimeters on their fleets to avoid interference. (At a cost to thr airlines, not the 5G networks, I might add).
There is no reason why a mobile/cellular operator should pay for the older altimeters' upgrade. Each national regulator (in this case, FCC) is responsible for assigning the radio frequencies. The frequencies are always assigned only for a limited time (e.g. 10 years). FCC started a frequency auction with the assumption that the frequency spectrum has already been cleared and not used by others. The whole process takes years (you can read more about this one here:
https://docs.fcc.gov/public/attachme...C-18-149A1.pdf).