Yes, I am always hear the beeps while I am at the gate area. I can hear the sound when the passengers is boarded. Which one first one is normal as E-Ticket.

Second one is twice beeps means is emergency exit row. If someone who sitting in exit row. Because I cannot sit there in Exit Row because I am hearing impaired policies.

Third one is Paper Boarding pass is not E-Ticket. They have different boarding pass as coupon for which specific is not normally the e-ticket.

Hope you will understandable which scanned is beep you can go ahead onboard the aircraft. Thank you for the understanding.