Mobile Based Trigger System Using Near Ultrasonic Waves
Nilav Vaghasiya, Kevalkumar Ramoliya, Kaviraj Soni, Milap Bhatt · 2018 International Conference on Smart City and Emerging Technology (ICSCET) · 2018
High-frequency sound waves have a wide spectrum of application in multifarious fields making them an ideal choice for short distance data transmission. A trigger system based on audio beacon uses inaudible high-frequency sound waves to trigger an action on the target user's mobile device. The fundamental idea is to encode the information bits in the sound waves by varying the phase property of the carrier wave, for which phase shift keying is implemented. The beacon emits specific inaudible audio signals, which when received by the device results into some action on the target device. There is no such requirement of special hardware as the audio signals can be played on any traditional speaker set and received by most of the current mobile devices having a microphone. The accuracy of the system strongly relies on the proximity and the amount of noise interference between the beacon and user device. Few of the use cases for such systems include customer tracking inside a shopping mall i.e. in which shop the customer is and showcase of relevant ads based on how long the customer has been in there, approximate location tracking of the user within a premise, using the trigger system as a secondary authentication factor, invoking a certain function or a combination of functions on a mobile device by triggering audio signals.