Signal To Noise Acoustic
Mostrando 13-16 de 16 artigos, teses e dissertações.
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13. Redução adaptativa de eco e de ruído para terminais viva-voz. / Speech enhancement and acoustic echo cancellation for hands-free sets.
There is currently great motivation in developing hands-free devices which offer users, engaged in a telephone conversation, a good level of naturalness and intelligibility. In this work, the goal is to present a solution for two well-known problems that occur when designing a hands-free device for use in automobile environments: (1) the acoustic echo coupli
Publicado em: 2002
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14. Uma contribuição a minimização de jitter acustico em sistemas solitonicos
As the transmission rates of fiber optic systems increase, effects arising from fiber nonlinearities need to be taken into account in analises and simulations. For high rate systems (10-20 Gbps per channel) with large spacings between amplifiers, high intensity optical pulses, capable of exciting the nonlinearities, are required so that adequate signal to no
Publicado em: 1999
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15. Vibro-acoustography: An imaging modality based on ultrasound-stimulated acoustic emission
We describe theoretical principles of an imaging modality that uses the acoustic response of an object to a highly localized dynamic radiation force of an ultrasound field. In this method, named ultrasound-stimulated vibro-acoustography (USVA), ultrasound is used to exert a low-frequency (in kHz range) force on the object. In response, a portion of the objec
The National Academy of Sciences.
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16. Ultrasonic tagging of light: Theory
A theory is provided for the detection efficiency of diffuse light whose frequency is modulated by an acoustical wave. We derive expressions for the speckle pattern of the modulated light, as well as an expression for the signal-to-noise ratio for the detector. The aim is to develop a new imaging technology for detection of tumors in humans. The acoustic wav
The National Academy of Sciences.