The IR signal will be very powerful to make certain the earpiece can pick it up regardless of positioning.
A radio earpiece is risky because that is the most expected device...IR earpieces are OLD technology.
IR signals can even pass through human flesh....you can test this by pressing your TV remote into your palm and placing your hand close to the TV set remote pickup...the signal goes right through your hand. And that is a weak TV remote signal.
I built an high-powered IR array on a piece of perfboard and hooked it to a TV-Be-Gone transmitter and was able to turn TV sets off in the homes across the street...lol
