IEEE Transactions on Acoustics, Speech, and Signal Processing

The author states that the method of S.M. Kay and R. Sudhaker (ibid., vol.ASSP-34, p.96-104, Feb. 1986) can be easily modified to provide for (1) invariance of the autocorrelation function to processing and clipping, and (2) spectral estimation by fast Fourier transform of the zero-crossing intervals.<> View full abstract»

The commenter states that, because of the use of Farey sequences the result stated by N. Tepedelenlioglu (ibid., vol.37, no.7, p.1146-7, 1989) becomes a statement about D/sub N/, the number of elements in a Farey sequence of order N. Tepedelenlioglu's formula is then equivalent to a formula about Farey sequences given by M.R. Schroder (1986) C.M. Rader (1977). Thus, for example, while a standard F... View full abstract»

A generalization of the statistical approach of D.S.K. Chan and L.R. Rabiner (IEEE Trans. Audio Electroacoust., vol.AU-21; p.354-66, Aug. 1973) for predicting the effects of quantized coefficients in direct-form finite-impulse response (FIR) filters is presented. The analysis is used on more sophisticated quantizing procedures involving linear feedback of rounding errors. It is shown that the expe... View full abstract»

The results of an experiment on talker-dependent, connected-speech recognition of 10 Estonian words are reported. The words differ in so-called distinctive quantity, the major acoustic correlate of which is duration. These were consonant-vowel-vowel words, each word modeled with four variable-duration states. The words were spoken, and recognized, in sentence pairs of the form `Did you say (word 1... View full abstract»

The problem of predicting the next word a speaker will say, given the words already spoken; is discussed. Specifically, the problem is to estimate the probability that a given word will be the next word uttered. Algorithms are presented for automatically constructing a binary decision tree designed to estimate these probabilities. At each node of the tree there is a yes/no question relating to the... View full abstract»

A look-ahead approach (referred to as scattered look-ahead) to pipeline recursive loops is introduced in a way that guarantees stability. A decomposition technique is proposed to implement the nonrecursive portion (generated due to the scattered look-ahead process) in a decomposed manner to obtain concurrent stable pipelined realizations of logarithmic implementation complexity with respect to the... View full abstract»

Necessary and sufficient conditions are derived for the unique localization of narrowband sources having the same known center frequency by passive sensor arrays. The conditions specify the maximum number of sources that can be uniquely localized by a general array that satisfies some mild geometric constraints. The conditions are expressed in terms of the number of sensors and the rank of the cor... View full abstract»

A computationally efficient method for adaptive image estimation is developed, based on the multichannel form of the one-dimensional fast least-squares algorithms. Extended forms of various two-dimensional autoregressive image models are derived and used for this purpose. It is shown that the method, named the fast multichannel space recursive estimation technique (FAMSRET), can overcome image bou... View full abstract»

An approach to the general problem of signal parameter estimation is described. The algorithm differs from its predecessor in that a total least-squares rather than a standard least-squares criterion is used. Although discussed in the context of direction-of-arrival estimation, ESPRIT can be applied to a wide variety of problems including accurate detection and estimation of sinusoids in noise. It... View full abstract»

The problem of tracking time-varying linear systems is discussed. The focus is on the model quality in terms of the mean square error (MSE) between the true (momentary) transfer function and the estimated one. This MSE is thus a function of frequency. The exact expression for the MSE is complicated, but simple expressions that are asymptotic in the model order are developed for model structures of... View full abstract»

The authors present a novel bandlimited extrapolation method that incorporates qualitative prior knowledge of the distribution of signal energy in both the time domain (spatial domain) and the frequency domain. The extrapolation is easily computed by simple noniterative algorithm. The prior information is incorporated by means of a weighted energy measure, and the resulting solution is derived by ... View full abstract»

For pt.I see ibid., vol.37, no.7, p.1099 (1989). Block implementation and fine-grain pipelined block implementation of recursive digital filters are discussed. A new technique of incremental output computation is introduced which requires a linear complexity in block size. Based on the clustered look-ahead and incremental output computation approaches, incremental block-state structure is derived ... View full abstract»

Two methods for estimation of noise correlations along an array of sensors are presented. Both rely on a parametric (autoregressive moving average) noise model. The model has the advantage of describing the noise correlations by a small number of parameters and can be applied to a great variety of physical noises. The first method is related to the calculation of the likelihood of whitened observa... View full abstract»

A technique is developed for the design of analysis filters in an M-channel maximally decimated, perfect reconstruction, finite-impulse-response quadrature mirror filter (FIR QMF) bank that has a lossless polyphase-component matrix E(z). The aim is to optimize the parameters characterizing E(z) until the sum of the stopband energies of the analysis filt... View full abstract»

A single-chip, dedicated processor for implementation of pyramid vector quantization (PVQ) is presented. The computational requirements of the vector quantizer encoding the algorithm are described, and a processor architecture and instruction set are selected for efficient implementation of the vector quantization. The architecture's performance was simulated at the register transfer level with th... View full abstract»

Perfect reconstruction finite impulse-response (FIR) filter banks are analyzed both in the z-transform and time domains, showing the alternatives between designs in the two domains. Various classes of perfect reconstruction schemes are indicated, and relations between previously known systems are given. Windowed modulated filter banks with low computational complexity and perfect reconstr... View full abstract»

The problem is discussed of determining the source coherency structure and estimating the directions of arrival in the presence of coherent signals. The method is closely related to the smoothed rank profile (SRP) algorithm, which shows that for determining the source coherency structure, the number of elements required is greater than or equal to the total number of sources plus the highest degre... View full abstract»

It is shown that the number of data points the arithmetic Fourier transform (AFT) needs for an N-point Fourier transform is proportional to N². Thus, for example, while a standard fast Fourier transform algorithm requires 1024 samples to yield 1024 spectral components, AFT would take more than 300000 samples to do the same job View full abstract»