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Re:Apple Introduces AirTag by john_payette on Tuesday April 20, 2021 @02:34PM (#26879002)
This tag has an U1 chip using Ultra Wide Band (UWB) which means that iPhones 11 and above also equipped with those chips will be able to locate those tags from 80m away with a +/-30cm accuracy. U1 UWB uses short pulses at 6.24GHz and 8.2GHz and positioning is done by combining time of flight (ToF) and angle of arrival (AoA).
Re:Apple Introduces AirTag by snailmailman on Tuesday April 20, 2021 @03:59PM (#26880674)
I'm really curious how accurate this ends up being. Bluetooth location is one thing, but I've never seen bluetooth that can do anything more accurate than "X meters away"

These UWB chips claim to do "X meters away in Y direction". The direction aspect could be revolutionary if it works well. AirTags is the perfect use for it as well.

Re:Apple Introduces AirTag by andrewl-hn on Wednesday April 21, 2021 @06:38PM (#26896301)
Our company experiments with indoor location tracking using UWB beacons. We've got a few demo kits from different vendors to test it out.

Overall, If you have a UWB receiver devices installed ~ every 4-5 meters (15 feet) you can triangulate beacon's position to a pretty precise degree (around 10 cm / 4 inches accuracy). You can even detect the height of a beacon above the floor.

However, triangulation is the key. Often we have to install extra receivers just to deal with big columns and barriers, sources of intense electromagnetism (like big electric engines or microwaves), or some materials (glass doors turned out to be a major problem, wooden doors - not so much).

I'm not sure how accurate a positioning can be with your phone acting as a sole UWB receiver. Clearly Apple can make it work sufficiently well for an everyday use, but it won't be as precise as they show in carefully constructed demos.

Re:Apple Introduces AirTag by andiareso on Tuesday April 20, 2021 @05:04PM (#26881656)
"+/- 30cm" ?
Re:Apple Introduces AirTag by snailmailman on Tuesday April 20, 2021 @05:39PM (#26882131)
Compared to a dot on a map that usually just narrows it down to an entire building?

If the sound is muffled and you can’t hear it, this sounds like it could narrow it down to a specific room or maybe even area of a room. Which is a huge improvement.

I haven’t personally used a Tile before, but my impression was “you get what building it’s in, then have to search everywhere til it’s in earshot”

Re:Apple Introduces AirTag by oh_sigh on Tuesday April 20, 2021 @06:28PM (#26882730)
The finding app has an arrow on it, pointing you towards the signal. So maybe the map has only building-level resolution, but once you're in the building you just follow the arrow until it says you're standing on it.
Re:Apple Introduces AirTag by slimsag on Tuesday April 20, 2021 @09:28PM (#26884351)
Tile trackers are accurate within +-90cm based on some empirical tests I did for using them to monitor my cat's activity throughout my house.

So Apple's +-30cm does seem to be a fairly major improvement, if true.

Re:Apple Introduces AirTag by TechBro8615 on Tuesday April 20, 2021 @11:31PM (#26885132)
That’s a 60cm range, which is non trivial. It’s about the length of a human arm. Many desks are 120cm wide, so half of that.
Re:Apple Introduces AirTag by ericklestrange on Wednesday April 21, 2021 @12:16PM (#26891611)
im also super curious of this, i wanted to do a DIY angle of arrival necklace some time ago and last time i checked you required a whole mini antenna to achieve that!
Re:Apple Introduces AirTag by dakial1 on Sunday April 25, 2021 @10:49AM (#26933150)
I wonder if Apple will use this product as a Guinea Pig to test the possibility of building a device-to-device network over UWB. From what I've read (I'm not technical) this was tried sometime ago by a consortium but they gave up over the difficulties of sending communications over UWB. Maybe Apple will manage a breaktrough by pouring money and brains over it like it did with M1?
Re:Apple Introduces AirTag by ericklestrange on Wednesday April 21, 2021 @12:25PM (#26891767)
https://m.youtube.com/watch?v=jSDtUOQXJmo

two antennas using time of flight to achieve angle of arrival

Re:Apple Introduces AirTag by neop1x on Wednesday April 21, 2021 @07:21PM (#26896618)
UWB is also integrated in the newest Samsung phones https://www.theverge.com/2021/4/8/22373410/samsung-galaxy-sm...
Re:Apple Introduces AirTag by mentos on Tuesday April 20, 2021 @08:29PM (#26883883)
I wonder if you can repurpose these for motion capture? Glue one to each joint and increase the update frequency?
Re:Apple Introduces AirTag by paultopia on Tuesday April 20, 2021 @09:29PM (#26884360)
Does anyone have any clue about whether other devices with a U1 chip will also be able to do that? (I'm thinking about people like me, who have an apple watch 6---which does have the U1 chip---but are a few generations behind on the iphone)
Re:Apple Introduces AirTag by rx_tx on Wednesday April 21, 2021 @02:11AM (#26885955)
I would be surprised if the next airpods case doesn't have the UWB location feature as well.