What protocol, frequency band and messaging style is used by typical popular true wireless earbuds between the two ears? Is it another Bluetooth connection? Bluetooth LE, or something proprietary to the chipset?
In typical popular true wireless earbuds, I understand in stereo mode only one bud communicates with the source device, and relays audio data to the other earbud over a secondary connection. Is my understanding correct? How do they deal with the challenge of transmitting through the wearer's head (or around)?
Thanks in advance for any pointers to a technical description. If there is no commonality between different devices, feel free to describe the model for a particular popular device eg AirPods, Jabra 65t, etc or chipset manufacturer (Qualcomm, Realtek etc)
Best Answer
I can't stand not knowing how this works so I did some research by reading some patents - their language is intentionally vague in some areas, but I did discover some commonalities in what they considered to be current normal practice:
The whole concept of true wireless earbuds is so new that almost everything published about it is from 2016 or later, and the devices back in 2016 and 2017 were primitive by today's standards.