| Autor: |
Flanagan, J. L., Shipley, K. L., Nelson, J. R., Johnston, J. D., Bottone, P. |
| Zdroj: |
Journal of the Acoustical Society of America; 1981, Vol. 70 Issue S1, pS79-S79, 1p |
| Abstrakt: |
Two recent advances in acoustics technology open new possibilities for improving teleconferencing in large rooms. High-quality, inexpensive electret microphones can be used in sizeable numbers to form controllable arrays, or can be constructed as planar mosaics to which beam-forming computation can be applied. Ever-diminishing cost of digital computation, in the form of microcomputers, makes sophisticated per-channel processing feasible. We describe in this report the design of one-dimensional and two-dimensional microphone arrays, and their control for simple beam-forming by microprocessors. Computation essentially in real-time permits the beam to scan a given conference room space. Detection of speech at any given position can halt the scan and allow the beam to remain in that position until the signal subsides. We give calculated and measured responses for preliminary array designs, and circuit details for beam control by an MC68000 microprocessor. Extension of the technique to more sophisticated processing, such as matched filtering to achieve volume selectivity, is also discussed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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