Acoustic analog-to-digital converter using coupled waveguides in phononic crystals

Abstract

In this research, a novel application as an acoustic analog-to-digital converter (ADC) is introduced, utilizing all-solid phononic crystals. The structure consists of a two-channel directional coupler designed to achieve 2-bit quantization. As the input signal amplitude increases, additional stress is applied to the background, inducing a slight change in the mass density of the phononic crystal structure. This structure is composed of an array of iron scatterers embedded in a polymerization of methyl methacrylate (PMMA) medium, with a selected working frequency of 67.5 kHz. To guide the applied acoustic wave, a directional coupler is employed. In the proposed model, transmission values below 0.3 are interpreted as "0," while values exceeding 0.3 are considered "1." It is crucial that a transmission range of 0.4–0.6 signifies a logical "1" for both active outputs. The fabrication tolerance of the directional coupler rods has been calculated, and the maximum transmission change is equal to 0.03 in a 2 µm changing range around the central radius

Graphical Abstract

Keywords:

• Analog-to-digital converter
• mass density
• phononic crystals
• directional coupler

Acknowledgments

Not applied.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

None.