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Yes exactly that. The FCC allocated spectrum for radalts to use, then set aside an equivalent amount of spectrum (which is an insane amount of spectrum for a g

Yes exactly that. The FCC allocated spectrum for radalts to use, then set aside an equivalent amount of spectrum (which is an insane amount of spectrum for a guard band, easily double what most uses get) above and below the radalts spectrum as guard bands that no one is allowed to use. The guard bands ensure that if there is a little spill over from 5G (which there won’t be because modern radios are better than that), or if the radalts have crappy filtering on their front ends (which it seems they do). Then nothing bad will happen, because the guard bands give everyone lots of space for sloppy engineering (which Boeing seems to be abusing)

p_l 5y ago
Boeing is not abusing anything - they just published a study on the models of altimeters that were sold with their planes, in specific configurations. Similar studies are performed by Airbus, Bombardier, Dassault, Cessna, etc. etc. And FCC rules only specified transmission frequency of radar altimeters, and radio is analog and perfect filtering is close to impossible (especially with the kind of chirping signal radar altimeters use, where whole 200MHz of spectrum is spanned in single chirp)