The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
S. Varho - One of the best experts on this subject based on the ideXlab platform.
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A new predictive method for all-Pole modelling of speech spectra with a compressed set of parameters
1999 IEEE International Symposium on Circuits and Systems (ISCAS), 1999Co-Authors: S. Varho, P. AlkuAbstract:This paper presents a new linear predictive method for speech processing, Linear Prediction with Linear Extrapolation (LPLE). The proposed method reformulates the computation of linear prediction by combining preceding samples of x(n) into pairs of consecutive samples. Each sample pair determines a line, which is then extrapolated at time instant n to be used as a data sample in the prediction. Consequently, from p normal equations the LPLE-technique yields an all-Pole Filter of order 2p, while the corresponding all-Pole Filter given by conventional linear prediction (LP) is of order p. It appears that LPLE is able to model the spectrum of voiced speech more accurately than conventional LP with small p-values. In this paper the effect of the prediction order is studied by varying the p-value from 1 to 12 for both conventional LP and the LPLE-method. Finally, the resulting all-Pole spectra as well as the residual energies are compared.
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Regressive linear prediction with triplets-an effective all-Pole modelling technique for speech processing
1998 IEEE International Symposium on Circuits and Systems (ISCAS), 1998Co-Authors: S. Varho, P. AikuAbstract:This paper presents a new linear predictive method for speech processing, Regressive Linear Prediction with Triplets (RLPT). The RLPT-algorithm yields from p normal equations an all-Pole Filter of order 2p+1 (i.e., an all-Pole Filter of order 2p+1 is defined from p numerical values). In comparison to conventional linear prediction of order p RLPT takes into account 2p+1 preceding samples of x(n) in the computation of the linear prediction. Consequently, the obtained all-Pole Filter is able to model the spectrum of voiced speech more accurately than conventional linear prediction, especially with very small p-values. The experiments show that the RLPT-method is effective in finding one or two lowest resonances in voiced speech spectra when p equals 1 or 2.
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Spectral estimation of voiced speech with regressive linear prediction
9th European Signal Processing Conference (EUSIPCO 1998), 1998Co-Authors: S. Varho, Paavo AlkuAbstract:A new predictive algorithm for the spectral estimation of voiced speech, Regressive Linear Prediction (RLP), is presented in this paper. Unlike conventional linear prediction (LP), RLP first combines the values that preceed the sample x(n) into groups of three consecutive samples (i.e., x(n-i), x(n-i-1), x(n-i-2)). Each of these p groups is then used to determine a regression line the value of which at time n are used as a data sample in the prediction. The prediction is optimised by minimising the square of the error between the original sample and the predicted value according to the autocorrelation criterion. With the same number p of unknowns in the normal equations, RLP yields an all-Pole Filter of order p+2, whilst the all-Pole Filter given by LP is of order p. The additional Poles of the RLP Filter improve the spectral modelling of voiced speech. This is shown in the present study by comparing the performance of conventional LP and the RLP method.
M J Lancaster - One of the best experts on this subject based on the ideXlab platform.
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the design of microstrip six Pole quasi elliptic Filter with linear phase response using extracted Pole technique
IEEE Transactions on Microwave Theory and Techniques, 2001Co-Authors: M J LancasterAbstract:The development of microstrip Filters has been in great demand due to the rapid growth of wireless communication systems in this decade. Quasi-elliptic response Filters are very popular in communication systems because of their high selectivity, which is introduced by a pair of transmission zeros. A number of ways of implementing the quasi-elliptic response Filter on microstrip have been studied over the last two decades, i.e., the cascaded quadruplet Filter, canonical Filter, and extracted-Pole Filter. However, there is very little information in the literature giving the design details for microstrip extracted-Pole Filters. In this paper, design equations of the extracted-Pole Filter for microstrip are reviewed. A new class of microstrip Filter is also presented here. This class of Filter will have a quasi-elliptic function response and at the same time linear phase in the passband. The linear phase of the Filter is introduced by an in-phase cross coupling, while the transmission zero is realized using an extracted-Pole technique. Experimental results, together with a theoretical comparison between the group delay of this design, and the conventional quasi-elliptic six-Pole Filter are also presented.
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design of highly selective microstrip bandpass Filters with a single pair of attenuation Poles at finite frequencies
IEEE Transactions on Microwave Theory and Techniques, 2000Co-Authors: Jiasheng Hong, M J LancasterAbstract:This paper presents the design of a class of highly selective microstrip bandpass Filters that consist of microstrip open-loop resonators that exhibit a single pair of attenuation Poles at finite frequencies. A practical design technique for this class of Filters is introduced, including tables and formulas for accurate and fast Filter synthesis. Two design examples of a six-Pole Filter with a fractional bandwidth of 7.331% at 955 MHz and an eight-Pole Filter with a fractional bandwidth of 10.359% at 985 MHz are described. Theoretical and experimental results are presented. The compact size and the excellent performance of this class of Filters have been demonstrated.
Paavo Alku - One of the best experts on this subject based on the ideXlab platform.
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All-Pole modeling technique based on weighted sum of LSP polynomials
IEEE Signal Processing Letters, 2003Co-Authors: Tom Bäckström, Paavo AlkuAbstract:This study presents a new technique called weighted-sum line spectrum pair (WLSP) where an all-Pole Filter is defined by using a sum of weighted line spectrum pair polynomials. The WLSP yields a stable all-Pole Filter of order m, whose autocorrelation function coincides with that of the input signal between indices 0 and m-1. By sacrificing the exact matching at index m, the WLSP models the autocorrelation of the input signal at the indices above m more accurately than conventional linear prediction (LP). Experiments with vowels show that, in comparison to the conventional LP, WLSP yields all-Pole spectra that model formants with an increased dynamic range between formant peaks and spectral valleys.
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ICASSP - All-Pole modeling technique based on the Weighted Sum of the LSP polynomials
IEEE International Conference on Acoustics Speech and Signal Processing, 2002Co-Authors: Paavo Alku, Tom BäckströmAbstract:With the order of prediction equal to m, conventional linear prediction (LP) yields an all-Pole Filter that matches exactly the autocorrelation function of the input signal between indices 0 and m. This study presents a new technique, Weighted-Sum Line Spectrum Pair (WLSP), where an all-Pole Filter is defined by using a sum of weighted LSP polynomials. WLSP yields a stable all-Pole Filter of order m, whose autocorrelation function coincides to that of the input signal between indices 0 and m −1. By sacrificing the exact matching of the autocorrelations at index m, WLSP models the autocorrelation of the input signal at the indices above m more accurately than conventional LP. The current paper presents mathematical properties of WLSP together with preliminary results on modeling of vowels. The results indicate that WLSP, in comparison to conventional LP is able to yield all-Pole Filters that model especially the upper formants with a larger dynamic range between formant peaks and spectral valleys.
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Spectral estimation of voiced speech with regressive linear prediction
9th European Signal Processing Conference (EUSIPCO 1998), 1998Co-Authors: S. Varho, Paavo AlkuAbstract:A new predictive algorithm for the spectral estimation of voiced speech, Regressive Linear Prediction (RLP), is presented in this paper. Unlike conventional linear prediction (LP), RLP first combines the values that preceed the sample x(n) into groups of three consecutive samples (i.e., x(n-i), x(n-i-1), x(n-i-2)). Each of these p groups is then used to determine a regression line the value of which at time n are used as a data sample in the prediction. The prediction is optimised by minimising the square of the error between the original sample and the predicted value according to the autocorrelation criterion. With the same number p of unknowns in the normal equations, RLP yields an all-Pole Filter of order p+2, whilst the all-Pole Filter given by LP is of order p. The additional Poles of the RLP Filter improve the spectral modelling of voiced speech. This is shown in the present study by comparing the performance of conventional LP and the RLP method.
Jiasheng Hong - One of the best experts on this subject based on the ideXlab platform.
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quasi elliptic function doublet Filters without cross coupling
European Microwave Conference, 2009Co-Authors: Wenxing Tang, Jiasheng HongAbstract:This paper presents a recent investigation of miniature microstrip doublet dual-mode Filters that exhibit quasi-elliptic function response without using any cross coupling. It shows that a single two-Pole Filter or the doublet can produce two transmission zeros resulting from a double behavior of the dual-mode resonator of this type. Electromagnetic (EM) simulation and experiment results are described. A four-Pole Filter of this type is demonstrated.
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Ultra-Wideband Bandpass Filter Using Multilayer Liquid-Crystal-Polymer Technology
IEEE Transactions on Microwave Theory and Techniques, 2008Co-Authors: Jiasheng HongAbstract:Novel ultra-wideband (UWB) bandpass Filters are proposed based on quasi-lumped-element prototypes and implemented with multilayer liquid-crystal-polymer (LCP) technology. In this study, the broadside-coupled microstrip radial stubs and high-impedance microstrip lines are adopted as quasi-lumped elements for realizing compact UWB bandpass Filters. By introducing a short-circuited high-impedance microstrip line as a shunt inductor and suitably designing quasi-lumped-element capacitors, a compact six-Pole bandpass Filter is implemented with the Federal Communications Commission (FCC) defined UWB specifications. To further improve the selectivity and wideband performance, an eight-Pole Filter of this type is developed by adding two shunt short-circuited microstrip stubs, which introduce a transmission zero at the upper passband edge. The proposed Filters are fabricated using multilayer LCP technology. Good agreement between simulated and measured results of these Filters are observed. The measured results show that the fabricated six-Pole Filter has good specifications for the FCC-defined UWB system. The fabricated eight-Pole Filter has an ultra-wide fractional bandwidth (139%) and a good stopband rejection level, which is higher than 38.1 dB from 10.57 to 18.0 GHz. The proposed Filters are attractive for UWB communications and radar systems.
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Dual-mode microstrip triangular patch resonators and Filters
IEEE MTT-S International Microwave Symposium Digest 2003, 2003Co-Authors: Jiasheng Hong, Shuzhou LiAbstract:Dual-mode operation of microstrip triangular patch resonators has been investigated. It has been found theoretically that the dual modes can result from the rotation and superposition of a fundamental mode. The characteristics of the dual modes and their mode splitting are described. The application of this new type of dual mode microstrip patch resonator in the design of microwave planar Filters is presented. A two-Pole Filter and one four-Pole Filter of this type are demonstrated for the first time. Both theoretical and experimental results are presented. Advantages of using this type of Filter are not only its lower loss and higher power handling capability, but also its compact size and natural circuit topology for implementing Filters.
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design of highly selective microstrip bandpass Filters with a single pair of attenuation Poles at finite frequencies
IEEE Transactions on Microwave Theory and Techniques, 2000Co-Authors: Jiasheng Hong, M J LancasterAbstract:This paper presents the design of a class of highly selective microstrip bandpass Filters that consist of microstrip open-loop resonators that exhibit a single pair of attenuation Poles at finite frequencies. A practical design technique for this class of Filters is introduced, including tables and formulas for accurate and fast Filter synthesis. Two design examples of a six-Pole Filter with a fractional bandwidth of 7.331% at 955 MHz and an eight-Pole Filter with a fractional bandwidth of 10.359% at 985 MHz are described. Theoretical and experimental results are presented. The compact size and the excellent performance of this class of Filters have been demonstrated.
S Mahadeva R Prasanna - One of the best experts on this subject based on the ideXlab platform.
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epoch extraction from telephone quality speech using single Pole Filter
IEEE Transactions on Audio Speech and Language Processing, 2017Co-Authors: C M Vikram, S Mahadeva R PrasannaAbstract:Epoch extraction from speech involves the suppression of vocal tract resonances, either by linear prediction based inverse Filtering or Filtering at very low frequency. Degradations due to channel effect and significant attenuation of low frequency components ( $ 300 Hz) create challenges for the epoch extraction from telephone quality speech. An epoch extraction method is proposed that considers the vertical striations present in the time-frequency representation of voiced speech as the representative candidates for the epochs. Time-frequency representation with better localized vertical striations is estimated using single Pole Filter based Filter bank. The time marginal of time-frequency representation is computed to locate the epochs. The proposed algorithm is evaluated on the database of five speakers, which provide simultaneous speech and electroglottographic recordings. Telephone quality speech is simulated using G.191 software tools. The identification rate of the state-of-the-art methods degrades substantially for the telephone quality speech whereas that of the proposed method remains the same, comparable to that of clean speech.
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Epoch Extraction From Telephone Quality Speech Using Single Pole Filter
IEEE ACM Transactions on Audio Speech and Language Processing, 2017Co-Authors: C M Vikram, S Mahadeva R PrasannaAbstract:Epoch extraction from speech involves the suppression of vocal tract resonances, either by linear prediction based inverse Filtering or Filtering at very low frequency. Degradations due to channel effect and significant attenuation of low frequency components (
