In this paper, we propose a new smart ordering application for assigning sequence numbers to customers.This system has here advantages over existing ordering systems, for example, it does not require identifying information such as phone numbers or social network IDs, and could therefore protect customer data.In this system, inaudible high frequencies between 18 kHz and 22 kHz are used for communication between speaker and microphone.To evaluate performance, the system was tested across smart devices including the Galaxy S7 and S8, and iPhones 6, 7, and 8, and the results showed a success rate of 98.
7%.The proposed system could be a useful service technology for offline sites that need to assign sequence numbers to customers click here because of high visitor rates.