TY - JOUR
T1 - Local Time-Domain Spherical Harmonic Spatial Encoding for Wave-Based Acoustic Simulation
AU - Bilbao, Stefan
AU - Politis, Archontis
AU - Hamilton, Brian
PY - 2019/4/1
Y1 - 2019/4/1
N2 - Volumetric time-domain simulation methods, such as the finite difference time domain method, allow for a fine-grained representation of the dynamics of the acoustic field. A key feature of such methods is complete access to the computed field, normally represented over a Cartesian grid. Simple solutions to the problem of extracting spatially encoded signals, necessary in virtual acoustics applications, result. In this letter, a simple time-domain representation of spatially encoded spherical harmonic signals is written directly in terms of spatial derivatives of the acoustic field at the receiver location. In a discrete setting, encoded signals may be obtained, at very low computational cost and latency, using local approximations with minimal number of grid points, and avoiding large convolutions and frequency-domain block processing of previous approaches. Numerical results illustrating receiver directivity and computed time-domain responses are presented, as well as numerical solution drift associated with repeated time integration.
AB - Volumetric time-domain simulation methods, such as the finite difference time domain method, allow for a fine-grained representation of the dynamics of the acoustic field. A key feature of such methods is complete access to the computed field, normally represented over a Cartesian grid. Simple solutions to the problem of extracting spatially encoded signals, necessary in virtual acoustics applications, result. In this letter, a simple time-domain representation of spatially encoded spherical harmonic signals is written directly in terms of spatial derivatives of the acoustic field at the receiver location. In a discrete setting, encoded signals may be obtained, at very low computational cost and latency, using local approximations with minimal number of grid points, and avoiding large convolutions and frequency-domain block processing of previous approaches. Numerical results illustrating receiver directivity and computed time-domain responses are presented, as well as numerical solution drift associated with repeated time integration.
KW - acoustic field
KW - acoustic signal detection
KW - acoustic signal processing
KW - encoding
KW - finite difference time-domain analysis
KW - frequency-domain analysis
KW - time-domain analysis
KW - repeated time integration
KW - computed time-domain responses
KW - frequency-domain block processing
KW - spatially encoded spherical harmonic signals
KW - simple time-domain representation
KW - virtual acoustics applications
KW - spatially encoded signals
KW - computed field
KW - fine-grained representation
KW - finite difference time domain method
KW - volumetric time-domain simulation methods
KW - wave-based acoustic simulation
KW - local time-domain spherical harmonic spatial encoding
KW - Time-domain analysis
KW - Acoustics
KW - Encoding
KW - Harmonic analysis
KW - Finite difference methods
KW - Three-dimensional displays
KW - Receivers
KW - Finite difference time domain (FDTD)
KW - room acoustics
KW - spatial audio
KW - microphone array
KW - spherical harmonics
KW - ambisonics
U2 - 10.1109/LSP.2019.2902509
DO - 10.1109/LSP.2019.2902509
M3 - Article
VL - 26
SP - 617
EP - 621
JO - IEEE Signal Processing Letters
JF - IEEE Signal Processing Letters
SN - 1070-9908
IS - 4
ER -