We investigate multilevel threshold systems with signal-dependent noise that transmit a common random input signal. We demonstrate the occurrence of M-ary suprathreshold stochastic resonance caused by the signal-depen...
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We investigate multilevel threshold systems with signal-dependent noise that transmit a common random input signal. We demonstrate the occurrence of M-ary suprathreshold stochastic resonance caused by the signal-dependent noise, and quantify the information enhancement that results relative to the absence of noise. We also find that in the case of Mary threshold systems, the values of mutual information and signal-to-quantization-noise ratio are larger than the corresponding values in the case of binary threshold systems. These results are potentially useful for understanding the encoding mechanism of inner-ear hair cells and other biological sensory systems. (C) 2017 Published by Elsevier B.V.
Newton's rings fringe pattern is often encountered in optical measurement. The digital processing of the fringe pattern is widely used to enable automatic analysis and improve the accuracy and flexibility. Before ...
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Newton's rings fringe pattern is often encountered in optical measurement. The digital processing of the fringe pattern is widely used to enable automatic analysis and improve the accuracy and flexibility. Before digital processing, sampling and quantization are necessary, which introduce quantization errors in the fringe pattern. quantization errors are always analyzed and suppressed in the Fourier transform (FT) domain. But Newton's rings fringe pattern is demonstrated to be a two-dimensional chirp signal, and the traditional methods based on the FT domain are not efficient when suppressing quantization errors in such signals with large bandwidth as chirp signals. This paper proposes a method for suppressing quantization errors in the fractional Fourier transform (FRFT) domain, for chirp signals occupies little bandwidth in the FRFT domain. This method has better effect on reduction of quantization errors in the fringe pattern than traditional methods. As an example, a standard Newton's rings fringe pattern is analyzed in the FRFT domain and then 8.5 dB of improvement in signal-to-quantization-noise ratio and about 1.4 bits of increase in accuracy are obtained compared to the case of the FT domain. Consequently, the image quality of Newton's rings fringe pattern is improved, which is beneficial to optical metrology. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)
The minimization of cost, power consumption and time-to-market of DSP applications requires the development of methodologies for the automatic implementation of floating-point algorithms in fixed-point architectures. ...
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ISBN:
(纸本)0780374029
The minimization of cost, power consumption and time-to-market of DSP applications requires the development of methodologies for the automatic implementation of floating-point algorithms in fixed-point architectures. In this paper, a new methodology for evaluating the quality of an implementation through the automatic determination of the signal to quantizationnoiseratio (SQNR) is presented. The modelization of the system at the quantizationnoise level and the expression of the output noise power is detailed for linear systems. Then, the different phases of the methodology are explained and the ability of our approach for computing the SQNR efficiently is shown through examples.
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