An approach to designing the ultrasonic transducer emission array

In the field of directional sound source transmission, an important device for electro-acoustic energy conversion is the ultrasonic transducer. To achieve sound source clustering, it is necessary to make the wavelength of the sound wave much smaller than the diameter of the loudspeaker, in the range of ordinary audible sound frequencies, theoretically requires a traditional loudspeaker with a diameter of up to thousands of meters, which is unrealistic and cannot make the sound source directional. Using the characteristics of high frequency and short wavelength of ultrasound to modulate low frequency acoustic signals to high frequency ultrasound, the modulated signal is emitted by an emitting transducer, which is demodulated by the non-linear characteristics of air during propagation to produce low frequency audible sound, so that the directional transmission of sound waves is obtained. In this chapter, the basic working principle of the parametric emission array is studied, the factors affecting the directivity of the transducer array are analysed, the expression for the directivity of the uniform linear transducer array is derived, and the Matlab simulation test program is written according to the formula, and the three factors affecting the directivity of the acoustic beam, such as array element spacing, array size and emission frequency, are simulated and analysed one by one and conclusions are drawn.