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Published on: April 4, 2016
Acoustic reciprocity: An extension to spherical harmonics domain
Prasanga Samarasinghe1, Thushara D Abhayapala1, Walter Kellermann2
1Research School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia prasanga.samarasinghe@anu.edu.au, thushara.abhayapala@anu.edu.au.
Acoustic reciprocity, a key wavefield property, is extended beyond simple sources. This study formulates the theory for directional transducers using spherical harmonics, enhancing acoustic measurements.
Area of Science:
- Acoustics
- Wave Propagation
- Transducer Technology
Background:
- Acoustic reciprocity is a fundamental principle simplifying acoustic measurements.
- The traditional reciprocity theorem applies to monopole point sources and receivers.
- Extending reciprocity to complex transducers is crucial for advanced applications.
Purpose of the Study:
- To formulate acoustic reciprocity theory for directional sources and receivers.
- To extend the application of reciprocity beyond simple monopole transducers.
- To analyze reciprocity in the spherical harmonics domain for higher-order directivity.
Main Methods:
- Formulation of acoustic reciprocity in the spherical harmonics domain.
- Theoretical analysis of directional transducers with higher-order directivity patterns.
- Mathematical derivation of the extended reciprocity theorem.
Main Results:
- A generalized acoustic reciprocity theory for directional transducers is presented.
- The formulation successfully incorporates higher-order directivity patterns.
- Demonstration of the applicability of the extended theorem in the spherical harmonics domain.
Conclusions:
- The study successfully extends the acoustic reciprocity theorem to directional transducers.
- This generalized theory simplifies measurements involving complex acoustic systems.
- The spherical harmonics domain provides a robust framework for analyzing directional acoustic reciprocity.
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