Parametric sound fields by phasecancellation excitation of primary waves
نویسندگان
چکیده
By radiating bifrequency primary waves from two ultrasonic emitters with changing the phases of the primary waves, we can obtain the sound fields that are different from the usual inphase excitation. Especially, for the excitation of out-phase by 180 degrees the difference frequency wave has the directivity of almost uniformity near the acoustic axis. Additionally, the sound pressure levels of the harmonic components of the difference frequency and the primary waves as well are suppressed by 10 dB and more.
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