An Array Filtering Implementation of a Constant-Beam-Width Acoustic Source

Harrell JA, Hixson EL. An Array Filtering Implementation of a Constant-Beam-Width Acoustic Source. J Audio Eng Soc. 1990;38(4):221-230. Available from: https://aes.org/publications/elibrary-page/?id=6040

@article{Harrell1990_6040,
  author = {Harrell, Jefferson A. and Hixson, Elmer L.},
  title = {{An Array Filtering Implementation of a Constant-Beam-Width Acoustic Source}},
  journal = {Journal of the Audio Engineering Society},
  volume = {38},
  number = {4},
  pages = {221--230},
  year = {1990},
  month = apr,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=6040}
}

TY  - JOUR
TI  - An Array Filtering Implementation of a Constant-Beam-Width Acoustic Source
AU  - Harrell, Jefferson A.
AU  - Hixson, Elmer L.
T2  - Journal of the Audio Engineering Society
J2  - J. Audio Eng. Soc.
VL  - 38
IS  - 4
SP  - 221
EP  - 230
PY  - 1990
DA  - 1990/04/06
UR  - https://aes.org/publications/elibrary-page/?id=6040
PB  - Audio Engineering Society
LA  - en
AB  - For acoustic arrays (microphones or loudspeakers) the main beam width of the radiation pattern is determined by the spacing between the elements in terms of the wavelength. Thus the beam pattern depends on the frequency. It is demonstrated that by controlling the spacing and the frequency response of a pair of superposed arrays, constant directivity of the main beam lobe over a wide frequency range can be achieved. Large powers can be achieved with relatively low energy densities at each element. A procedure is described by which line arrays of loudspeakers can be superposed with appropriate signal conditioning to control the main beam coverage with frequency. This methodology is extended to an X-shaped planar array for three-dimensional beam control with frequency. Computer models and experiments verify the process for one octave, and models are used to extend the method to wider frequency ranges and more optimal beam synthesis.
ER  -