I know uwb positioning used in apple devices and similar uses time of flight and angle of arrival to calculate positions of devices. But how do those systems make sure they're receiving a signal directly from the transmitter instead of a signal bouncing off a wall? I know uwb is low frequency and can go through most walls but assuming it bounces off, how can this be calculated?
1 Answer
Apple’s implementation is very good in my testing. The main calculation is time of flight and doppler and signal strength together making it very hard for reflections to dramatically alter the answer you get.
I’ve played with one tag and now have 5 and they are amazingly accurate in challenging RF environments. I haven’t been able to trip up the algorithm or the sensors so Apple has clearly put a lot of engineering and testing into these small items.
