Tài liệu Advanced DSP and Noise reduction P11 pdf

... Additive White Noise. IEEE Trans. Acoustics, Speech and Signal Processing, ASSP-26, 5, pp. 471–472. L INHARD K. and K LEMM H. (1997) Noise Reduction with Spectral Subtraction and Median Filtering ... mean and the variance of the noise. Note that the amount over-subtracted is the standard deviation of the noise. This heuristic formula is appealing because at one extreme...

Ngày tải lên: 26/01/2014, 07:20

... 80 Hz; band 2 is band-pass and covers 80 Hz to 3 kHz; band 3 is high-pass and covers above 3 kHz; and band 4 is also high-pass and covers above 9 kHz. At the encoder the gain of each band is ... time delay, and can be adjusted to coherently combine the signals. The magnitude frequency response of each filter can be used to remove the out–of–band noise. 1.3.8 Dolby Noise...

Ngày tải lên: 21/01/2014, 07:20

... Autocorrelation and power spectrum of impulsive noise. Impulsive noise is a random, binary-state (“on/off”) sequence of impulses of random amplitudes and random time of occurrence. In Chapter 12, a random ... speech and noise are at least in part random. The concept of randomness is closely associated with the concepts of information and noise. Indeed, much of the work on t...

Ngày tải lên: 21/01/2014, 07:20

... Additive Noise Reduction Consider a signal x(m) observed in a broadband additive noise n(m)., and model as y ( m ) = x ( m ) + n ( m ) (6.45) Assuming that the signal and the noise are ... signal, the noise- free signal and the noise respectively, and r xy is the cross- correlation vector of the noisy signal and the noise- free signal. Substitution of Equati...

Ngày tải lên: 21/01/2014, 07:20

... v N } span the noise subspace and have σ n 2 as their eigenvalues. Since the signal and noise eigenvectors are orthogonal, it follows that the signal subspace and the noise subspace are ... matrices of the signal x and the noise as I 2H n σ+= += SPS RRR nnxx yy (9.93) where R xx =SPS H and R nn = σ n 2 I are the autocorrelation matrices of the signal and n...

Ngày tải lên: 26/01/2014, 07:20

... impulsive noise removal system should utilise (a) the distinct features of the noise and the signal in the time and/ or frequency domains, (b) the statistics of the signal and the noise processes, and ... Impulsive Noise 359 12.1.1 Autocorrelation and Power Spectrum of Impulsive Noise Impulsive noise is a non-stationary, binary-state sequence of impulses with...

Ngày tải lên: 26/01/2014, 07:20

... convergence. The sub-band- based system is shown in Figure 14.11. The sub-band analyser splits the input signal into N sub-bands. Assuming that the sub-bands have equal bandwidth, each sub-band occupies ... telephone and data telecommunication systems, and acoustic feedback echoes from microphone–loudspeaker systems. E Advanced Digital Signal Processing and Noise Reduction, Seco...

Ngày tải lên: 26/01/2014, 07:20

... noise or any wideband noise whose spectrum has a non-flat shape; examples are pink noise, brown noise and autoregressive noise. (e) Impulsive noise: consists of short-duration pulses of random ... Estimation and Modulation Theory. Parts I, II and III. Wiley, New York. 2 NOISE AND DISTORTION 2.1 Introduction 2.6 Thermal Noise 2.2 White Noise 2.7 Shot...

Ngày tải lên: 21/01/2014, 07:20

... with mean vector µ x and covariance matrix Σ xx , and that the noise n (m) is also Gaussian with mean vector µ n and covariance matrix Σ nn . The signal and noise pdfs model the prior ... () 2 ,),())(( xxX mxmxf σµ N = and () 2 ,),())(( nnN mnmnf σµ N = are the Gaussian pdfs of the signal and noise respectively. Substitution of the signal and noise pdfs in Equ...

Ngày tải lên: 21/01/2014, 07:20

... signal and the noise HMMs maybe expressed as ()       = η ,,,maxmaxarg noisesignalsignal noise signal M ssYs Y s s f MAP (5.46) and ()         = η ,,,maxmaxarg noisesignalnoise signal noise M ssYs Y s s f MAP ... filtering and the spectral subtraction methods described in Chapters 6 and 11) or by combining the noise and the signal models to model the n...

Ngày tải lên: 21/01/2014, 07:20