This Pixel 4 XL teardown shows just how small the Soli system is
Google made the unconventional (by 2019 standards) decision to skip the notch on the Pixel 4 in favor of an old-fashioned top bezel in order to fit in all of the advanced face unlock and Soli radar tech.
from https://www.theverge.com/circuitbreaker/2019/10/24/20930168/google-pixel-4-xl-teardown-ifixit-soli-radar-screen-repair-motion-sense
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