the bandwidth of bandlimited signals.

Abstract—Image-scrambling schemes are designed to render the image content unintelligible. Wyner has proposed an elegant one-dimensional (1-D) scrambling scheme without bandwidth expansion, making use of the discrete prolate spheroidal sequences (DPSS). The DPSS are optimal regarding their energy

Many communication systems are bandwidthexpanding: the transmitted signal occupies a bandwidth larger than the symbol rate. The sampling theorems of Kotelnikov, Shannon, Nyquist et al. [1] shows that in order to represent a bandlimited signal, it is necessary to sample at what is popularly referred

. An example construction of a 2: n expansion mapping using the dissection technique is presented and is shown to exhibit optimal scaling of the MSE with the channel SNR. I.

is the method of choice -it is both effective and simple. Other methods to prematurely terminate the iterative solution of the correlation equations for conditioning is minimal. This report also discusses bandwidth expansion of the prediction coefficients after LP analysis using radial scaling of the z

Abstract — Recently, a new image scrambling (i.e., encryption) scheme without bandwidth expansion was proposed based on two-dimensional (2-D) discrete prolate spheroidal sequences (DPSS). A comprehensive cryptanalysis is given here on this image scrambling scheme, showing

We present a new statistical technique for the estimation of the high frequency components (4-8kHz) of speech signals from narrow-band (0-4 kHz) signals. The magnitude spectra of broadband speech are modeled as the outcome of a Polya Urn process, that represents the spectra as the histogram of the outcome of several draws from a mixture multinomial distribution over frequency indices. The multinomial distributions that compose this process are learnt from a corpus of broadband (0-8kHz) speech. To estimate high-frequency components of narrow-band speech, its spectra are also modeled as the outcome of draws from a mixture-multinomial process that is composed of the learnt multinomials, where the counts of the indices of higher frequencies have been obscured. The obscured high-frequency components are then estimated as the expected number of draws of their indices from the mixture-multinomial. Experiments conducted on bandlimited signals derived from the WSJ corpus show that the proposed procedure is able to aaccurately estimate the high frequency components of these signals.

We present a new statistical technique for the estimation of the high frequency components (4-8kHz) of speech signals from narrow-band (0-4 kHz) signals. The magnitude spectra of broadband speech are modelled as the outcome of a Pólya Urn process, that represents the spectra as the histogram of the outcome of several draws from a mixture multinomial distribution over frequency indices. The multinomial distributions that compose this process are learnt from a corpus of broadband (0-8kHz) speech. To estimate high-frequency components of narrow-band speech, its spectra are also modelled as the outcome of draws from a mixture-multinomial process that is composed of the learnt multinomials, where the counts of the indices of higher frequencies have been obscured. The obscured high-frequency components are then estimated as the expected number of draws of their indices from the mixture-multinomial. Experiments conducted on bandlimited signals derived from the WSJ corpus show that the proposed procedure is able to accurately estimate the high frequency components of these signals.

of bandwidth expansion is considered. The advantage in the protection ratio combined with the resulting expanded channel spacing are weighed using an equation devised by the authors to deduce whether or not such expansion is spectrally justifiable. Various analogue and digital systems,are considered

PAPER AWARD – Lossy transmission of a Gaussian source over an additive white Gaussian (AWGN) channel with side information at the decoder is tackled under the regime of bandwidth expansion. A previously known scheme, hybrid dig-ital/analog Wyner-Ziv (HDA-WZ) coding is shown to remain optimal when