A Fifty-Node Lebedev Grid And Its Applications To Ambisonics

Lecomte P, Gauthier PA, Langrenne C, Berry A, Garcia A. A Fifty-Node Lebedev Grid And Its Applications To Ambisonics. J Audio Eng Soc. 2016;64(11):868-881. doi:10.17743/jaes.2016.0036

@article{Lecomte2016_18524,
  author = {Lecomte, Pierre and Gauthier, Philippe-Aubert and Langrenne, Christophe and Berry, Alain and Garcia, Alexandre},
  title = {{A Fifty-Node Lebedev Grid And Its Applications To Ambisonics}},
  journal = {Journal of the Audio Engineering Society},
  volume = {64},
  number = {11},
  pages = {868--881},
  year = {2016},
  month = nov,
  publisher = {Audio Engineering Society},
  doi = {10.17743/jaes.2016.0036},
  url = {https://doi.org/10.17743/jaes.2016.0036}
}

TY  - JOUR
TI  - A Fifty-Node Lebedev Grid And Its Applications To Ambisonics
AU  - Lecomte, Pierre
AU  - Gauthier, Philippe-Aubert
AU  - Langrenne, Christophe
AU  - Berry, Alain
AU  - Garcia, Alexandre
T2  - Journal of the Audio Engineering Society
J2  - J. Audio Eng. Soc.
VL  - 64
IS  - 11
SP  - 868
EP  - 881
PY  - 2016
DA  - 2016/11/06
DO  - 10.17743/jaes.2016.0036
UR  - https://doi.org/10.17743/jaes.2016.0036
PB  - Audio Engineering Society
LA  - en
AB  - Physical reconstruction or synthesis of three-dimensional sound fields can be implemented with Near Field Compensated Higher Order Ambisonics. This paper investigates the use of a fifty-node Lebedev grid, which is derived from rotationally-invariant quadrature rules. Special attention is paid to spatial aliasing artifacts at the capture and reproduction steps. While comparing a fifty-node Lebedev grid with a Fliege and a t-design grid that both use almost the same number of nodes, it is shown that the Lebedev grid provides the best performance in terms of sound field capture and reproduction. Finally, a multiband multiorder decoder is presented. These decoders take advantage of the inherent nested subgrids when following the rotationally-invariant quadrature approach. The importance of orthonormality of the spherical harmonics was highlighted in a context of physical encoding or reconstruction of a sound field with the Ambisonics approach. Simulation results are provided for the case of a three-band decoder using the three grids contained in the Lebedev grid. It was found that a multifrequency sound field can be reproduced accurately in the sweet-spot by using a combination of low-order decoder for low frequency and higher-order decoder for higher frequency.
ER  -