Radar altimeters are inherently wideband devices, designed without any historical need for front-end rejection and the specifications for them reflect that - th

Radar altimeters are inherently wideband devices, designed without any historical need for front-end rejection and the specifications for them reflect that - the RF "testing mask" that's used isn't a sharp rolloff at the edge of the RA allocation. Typical implementations are, for example, only 20 dB down for frequency-dependent rejection by 3.5 GHz. With potentially high gains from beamforming, both the fundamental mode and spurious emissions from 5G radios exceed the safe interference limits for the current RA specifications by at least 10 dB.