The iPhone 12 is rumored to get support for 802.11ay, a high speed and low latency Wi-Fi standard. Jason Cross posits that it could be used for Apple’s AR glasses.
The alternative is to make the headset a relatively dumb set of displays and cameras, with all the processing happening on some sort of base station—like your new iPhone 12. An ultra-high speed, super low-latency connection like that provided by 802.11ay is a necessity to make that work.
A popular thought is that Apple Glasses will be an iPhone accessory like Apple Watch is (or, started out) with most or all of the processing happening on the iPhone.
Check It Out: Could iPhone 12’s Fast 802.11ay Wi-Fi Be For AR Glasses?