Re:FAA says 5G could impact radio altimeters on most Boeing ...
by amirhirsch on Thursday February 24, 2022 @12:55AM
(#30450974)
The conclusions in the report are more severe than your comments are presenting. I don't think this is a good forum to discuss it further though. There is another comment suggesting a clash of two vastly different safety cultures that really hits the nail on the head, and I think that even the hypothesized/speculative risk to aviation needs addressing, though you are also probably right that the aircraft industry wants cash from the telcos for a retrofit that they should pay for themselves and were willing to drag their feet assuming FAA would trump the FCC in this matter (they will). Frankly if they want digital pulse-compression radar altimeters that are going to operate even with adversarial interference, I built/am-building the most advanced matched filter in the world though it will cost a bit more than a sub-$1K High Pass Filter plugged in line with the antennae which is probably sufficient (though avionics safety requirements will probably find a way to make it $100K anyway)
Re:FAA says 5G could impact radio altimeters on most Boeing ...
by amirhirsch on Wednesday February 23, 2022 @11:52PM
(#30450424)
Thanks for sharing. Iām going to read this report now. Are you in Radar? Potentially looking for a job at a well-funded startup making very high powered phased arrays in c and x bands?
Re:FAA says 5G could impact radio altimeters on most Boeing ...
by upofadown on Wednesday February 23, 2022 @09:56PM
(#30449702)
>...unless the radar bandpass filters are from the 1960's ...
Were filters particularly bad in the '60s? If you claim to have run the numbers you will have to reveal your assumptions.
this is the white paper that the FAA bases their concerns on https://www.rtca.org/wp-content/uploads/2020/10/SC-239-5G-In...
that is the issue they are raising
I have run the numbers and there is no way even at phone full power that it can interfere unless it was less than 2m away even then it would have to be free space, etc.
the body losses, airframe, antenna back scatter all taken into account, very very unlikely unless the radar bandpass filters are from the 1960's