High-resolution spectral analysis using multiple interval adaptive prediction

The problem of adaptively detecting two sinusoids corrupted by noise is considered, with emphasis on resolution properties. The approach is to form a spectral estimate from the coefficients of a Δ -step-ahead adaptive predictor. A theoretical analysis reveals that attention to the choice of the prediction horizon Δ gives a distinct improvement in the spectral estimate and in the resolution of the signals. The theoretical results are illustrated with numerical examples. Comparisons with previously suggested techniques are also made

A New Approach to Subband Adaptive Filtering

Subband adaptive filtering has attracted much attention lately. In this paper, we propose a new structure and a new formulation for adapting the filter coefficients. This structure is based on polyphase decomposition of the filter to be adapted and is independent of the type of filter banks used in the subband decomposition. The new formulation yields improved convergence rate when LMS algorithm is used for coefficient adaptation. As we increase the number of bands in the filter, the convergence rate increases and approaches the rate that can be obtained with a flat input spectrum. The computational complexity of the proposed scheme is nearly the same as that of the fullband approach. Simulation results are included to demonstrate the efficacy of the new approach. Index Terms--- Acoustic echo cancellation, adaptive filtering, subband filtering. I. INTRODUCTION A COMMON problem encountered in telephone communication is the presence of echo, which is produced when the signal passes t..

Multiscale homogenization based analysis of polymeric nanofiber scaffolds

10.1080/15376490802470440Mechanics of Advanced Materials and Structures158558-56

Optimized lattice-form adaptive line enhancer for a sinusoidal signal in broad-band noise

An adaptive filter configuration, known as the adaptive line enhancer (ALE), has previously been suggested by Widrow et al for the detection of sinusoidal signals in wide-band noise. Some refinements of the ALE are suggested in this paper. First, for the special case of a single sinusoid, it is shown that there exists an optimum value of the so-called decorrelation parameter, which in earlier studies seems always to have been chosen equal to unity. Second, a lattice filter implementation of the general ALE is derived and turns out to be somewhat different from those suggested in the literature. Simulations are used to examine the behavior of the suggested schemes. The results show substantial improvements in the estimate of the unknown sinusoidal frequency, both with respect to bias and accuracy

A combined DMT/DWMT system for DSL application

Signal Processing801185-195SPRO