I was using the edimax nano adaprtor, and was disconected from the device often.
In fact the only way I could establish wifi communication was by connecting the ethernet cable and leave it hanging. I guess it add antena to the board.
I then got out and bought the WN722N Ver: 1.9
Very cheap and had a standard wifi antena.
fitting it between my beagle bone black and the OSBO board wasn’t easy, yet it works.
Now I don’t get disconnected , at all.
I didn’t need to add any drivers as it seems the image allready supprted the ath9k-htc module.
By te way linux fans can also use this wifi adaptor to achive miracast using the miraclecast project.
Enjoy,
Niv from Herzeliya