Fixed-point acoustic wave emission device based on the principle of parametric array

Abstract

The invention discloses a fixed-point sound wave emitting device based on the principle of a parameter array, and belongs to the technical field of directional sound wave emission. In order to solve the technical problem that the existing parametric array speakers can only transmit directionally but cannot limit the length of the sound field, and further improve the degree of control over the concentrated position of the sound field formed by the parametric array speakers, the present invention proposes a method that can limit the length of the sound field Fixed-point sound wave transmitter. The present invention limits the length of the sound field formed by the main modulation signal by inversely modulating and emitting the collected audio signal with an additional different carrier frequency, and realizes the function of limiting the length of the sound wave emitted by the parametric array loudspeaker. On the basis of the high directivity of the parametric array loudspeaker, the spatial position where it forms the sound field is further limited. At the same time, it also provides a more accurate and effective sound field formation method for the confidential transmission of sound, active noise control and other fields.

Description

technical field [0001] The invention belongs to the technical field of directional sound wave emission, and in particular relates to a fixed-point sound wave emission device based on the principle of parametric array. Background technique [0002] Parametric array loudspeaker is a modern sound field forming technology used to limit the range of sound field. The parametric array speaker is mainly composed of a signal acquisition module, a signal processing module and an ultrasonic transducer array. Its working method is to collect the audio signal to be transmitted through the signal collector and convert it into a digital signal and send it to the signal processor. Then, the signals are output to the ultrasonic transducer array by the signal processor for alignment, modulation, digital-to-analog conversion or pulse density modulation and power amplification. The signal modulated to the ultrasonic frequency band is transmitted into the air or other nonlinear medium through ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to propose a fixed-point sound wave emission device based on the principle of parametric array in order to solve the technical problem that the existing parametric array loudspeaker can only transmit directionally but cannot limit the length of the sound field.

Images