Patent
System using plurality of adaptive digital filters
TLDR
In this article, a main adaptive digital filter and a sub-adaptive digital filter are provided, and these two adaptive digital filters share a filter coefficient to be controlled, on the side of the main adaptive filter, the shared coefficient is updated so that the difference between the output and a desired response is minimized.Abstract:
A main adaptive digital filter and a sub adaptive digital filter are provided, and these two adaptive digital filters share a filter coefficient to be controlled. On the side of the main adaptive digital filter, the shared coefficient is updated so that the difference between the output and a desired response is minimized and on the side of the subadapted digital filter, the above-stated shared filter coefficient is updated so that the output is minimized. A prescribed limitation is given to the frequency characteristic of a filter coefficient to be adapted, by treating the input of the sub adaptive digital filter as a signal weighted on the frequency or a noise having its band limited with respect to the input signal or the output signal of the main adaptive digital filter, and coefficient updating control is conducted so that the coefficient will not go beyond the limitation.read more
Citations
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TL;DR: In this paper, a noise control system includes an error detector for detecting an error signal between the control sound and noise, an adaptive filter for outputting a control signal; and a coefficient updator for updating a coefficient of the adaptive filter.
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TL;DR: In this paper, the authors proposed a signal enhancement system that includes delay logic, a partitioned adaptive filter, and signal reinforcement logic to improve the understandability of speech or other audio signals.
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Adaptive equalizer having a variable step size influenced by output from a trellis decoder
TL;DR: In this paper, an adaptive equalizer comprises a decision device, a decision feedback equalizer coupled with the decision device; an FIR filter coupled to the decision unit; and a trellis decoder coupled with a decision unit to provide a reliability output and a decoded output.
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Coefficient updating method for an adaptive filter
TL;DR: In this paper, a coefficient updating method is used to stop updating filter coefficients for a plurality of adaptive filters when a convergence condition is achieved, i.e., when a minimum average value is reached.
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Active adaptive control system with weight update selective leakage
Jerry J. Trantow,Brian M. Finn +1 more
TL;DR: In this paper, a weight update signal is provided in response to a given condition of a given parameter, preferably output power of the correction signal, to control performance of the model, to selectively degrade same according to need.
References
More filters
PatentDOI
Electronic noise attenuation system
Minoru Takahashi,Tanetoshi Miura,Hareo Hamada,Hideki Hyoudo,Ryusuke Gotoda,Yasushi Yoshimura,Takashi Kuribayashi,Akio Akasaka +7 more
TL;DR: In this article, an electronic noise attenuation system for attenuating a sound wave propagated from a source of noise by generating another sound wave 180° out of phase and having the same sound pressure with the propagated sound wave from electro-mechanic transducer means disposed in a propagation passage of sound waves is presented.
Patent
Adaptive recursive least mean square error filter
TL;DR: In this article, an adaptive recursive filter is disclosed which comprises first and second adaptive transversal filters selectively coupled together to minimize the mean square error of the output data of recursive filter based upon observations of input data to the recursive filter.
Proceedings ArticleDOI
Acoustic noise suppression using regressive adaptive filtering
TL;DR: In this paper, the authors used a finite-impulse response adaptive filter with the stochastic gradient adaptation algorithm to achieve up to 12 dB of noise cancellation in the low end of the noise spectrum.