Abstract: A mobile terminal converts token information corresponding to card information to a sound wave signal and transmits the sound wave signal to a magnetic field conversion device, and the magnetic field conversion device restores the token information from the received sound wave signal, converts the token information to a magnetic field signal, and transmits the magnetic field signal to a merchant terminal, to perform payment.

Abstract: A mobile terminal converts token information corresponding to card information to a sound wave signal and transmits the sound wave signal to a magnetic field conversion device, and the magnetic field conversion device restores the token information from the received sound wave signal, converts the token information to a magnetic field signal, and transmits the magnetic field signal to a merchant terminal, to perform payment.

Abstract: An IoT switchgear operation system using sound wave communication including: a communication terminal for requesting, from an IoT switchgear via sound wave communication, one or more operations among manager registration, user registration, transmission of a changed password, transmission of a one-time digital key for a user, which is for the user himself/herself to open or close the IoT switchgear, and transmission of a one-time digital key for another person, which is for a terminal of another user to open or close the IoT switchgear; and the IoT switchgear for performing manager registration, user registration, a change of a password, storage of a one-time digital key for a user, and opening or closing of a door by using a one-time digital key for another person, which are requested by the communication terminal via sound wave communication with the communication terminal.

Abstract: A short-range payment system according to an embodiment of the present invention may include: a user terminal configured to transmit and receive a card information sound wave signal, which is a sound wave signal including card information, during operation in payment mode; a magnetic field converter configured to, when receiving the card information sound wave signal, extract the card information from the card information sound wave signal and generate a magnetic field that matches the extracted card information; and an MST payment device configured to perform payment processing by using the magnetic field generated by the magnetic field converter.

Abstract: A short-range payment system according to an embodiment of the present invention may include: a user terminal configured to transmit and receive a card information sound wave signal, which is a sound wave signal including card information, during operation in payment mode; a magnetic field converter configured to, when receiving the card information sound wave signal, extract the card information from the card information sound wave signal and generate a magnetic field that matches the extracted card information; and an MST payment device configured to perform payment processing by using the magnetic field generated by the magnetic field converter.

Abstract: A device for sound wave communication, including: a hardware correction table for setting a correction frequency band; a sound wave transmission unit for generating data frequencies at a predetermined base decibel level, generating separate reception filter frequencies at the base decibel level for receiving data carried by a sound wave transmitted from the nearest location when sound waves are received, and generating the correction reference frequency at the base decibel level for correcting hardware transmission; and a sound wave reception unit for receiving a sound wave signal transmitted from the sound wave transmission unit, extracting decibel levels at each of the data frequencies to form an array of decibel levels, correcting the array by shifting the array by a correction value extracted using the hardware correction table, and reconstructing data.

Abstract: A device for sound wave communication, including: a hardware correction table for setting a correction frequency band; a sound wave transmission unit for generating data frequencies at a predetermined base decibel level, generating separate reception filter frequencies at the base decibel level for receiving data carried by a sound wave transmitted from the nearest location when sound waves are received, and generating the correction reference frequency at the base decibel level for correcting hardware transmission; and a sound wave reception unit for receiving a sound wave signal transmitted from the sound wave transmission unit, extracting decibel levels at each of the data frequencies to form an array of decibel levels, correcting the array by shifting the array by a correction value extracted using the hardware correction table, and reconstructing data.