APPARATUS AND METHODS FOR DIRECTIONAL AUDIO RADIATION

摘要

The present invention relates to an apparatus and method for directional audio radiation in ultrasonic phase modulation or frequency modulation mode, using the linearity of an ultrasonic wave and the non-linearity of air as a medium for audio transmission. The present invention provides an apparatus for directional audio radiation comprises an ultrasonic phase modulation signal radiator or an ultrasonic frequency modulation signal radiator for receiving an audio signal, allowing the received audio signal to pass through a given correction device in order to obtain a correction signal, hase-modulating or frequency-modulating a first ultrasonic wave generated from an ultrasonic carrier wave generator using the correction signal, amplifying the phase­modulated or frequency-modulated first ultrasonic wave, and radiating the amplified ultrasonic wave; and an ultrasonic signal radiator for generating and amplifying a second ultrasonic wave having the same frequency as that of the first ultrasonic wave generated from the ultrasonic carrier wave generator, and radiating the amplified second ultrasonic wave into the air.