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The so-called Localized Waves (LW), and the "Frozen Waves" (FW), have arisensignificant attention in the areas of Optics and Ultrasound, because of theirsurprising energy localization properties. The LWs resist the effects ofdiffraction for large distances, and possess an interesting self-reconstruction(self-healing) property, after obstacles with size smaller than the antenna's;while the FWs, a sub-class of theirs, offer the possibility of arbitrarilymodeling the field longitudinal intensity pattern inside a prefixed interval,for instance 0 < z < L, of the wave propagation axis. More specifically, theFWs are localized fields "at rest", that is, with a static envelope (withinwhich only the carrier wave propagates), and can be endowed moreover with ahigh transverse localization. In this paper we investigate by simulatedexperiments, various cases of generation of ultrasonic FW fields, withfrequency f_o = 1 MHz in a water-like medium, taking account of the effects ofattenuation. We present results of FWs for distances up to L=80 mm, inattenuating media with absorption coefficients alpha in the range 70 < alpha <170 dB/m. Such simulated FW fields are constructed by using a proceduredeveloped by us, via appropriate finite superpositions of monochromaticultrasonic Bessel beams. We pay due attention to the selection of the FWparameters, constrained by the tight restrictions imposed by experimentalAcoustics, and to some practical implications of the transducer design. Theenergy localization properties of the Frozen Waves can find application even inmany medical apparatus, such as bistouries or acoustic tweezers, and fortreatment of diseased tissues (in particular, for the destruction of tumorcells, without affecting the surrounding tissues; besides for a safe kidneystone shuttering, etcetera).

Producing acoustic 'Frozen Waves': Simulated experiments with diffraction/attenuation resistant beams, in lossy media