On Passband and Stopband Cascaded-Integrator-Comb Improvements Using a Second Order IIR Filter

This paper proposes an efficient second order IIR filter which considerably improves the passband as well as the stopband of the cascaded-integrator-comb (CIC) filter. Using the polyphase decomposition of the proposed filter, all filtering can be moved to a lower rate, which is D times less than the high input rate, where D is the decimation factor. The overall phase response of the compensated CIC is approximately linear in the passband. The design parameters are the number of cascaded CIC filter N, the decimator factor D, the passband frequency wp, and a weighted parameter a

Optimal Sharpening of Compensated Comb Decimation Filters: Analysis and Design

Comb filters are a class of low-complexity filters especially useful for multistage decimation processes. However, the magnitude response of comb filters presents a droop in the passband region and low stopband attenuation, which is undesirable in many applications. In this work, it is shown that, for stringent magnitude specifications, sharpening compensated comb filters requires a lower-degree sharpening polynomial compared to sharpening comb filters without compensation, resulting in a solution with lower computational complexity. Using a simple three-addition compensator and an optimization-based derivation of sharpening polynomials, we introduce an effective low-complexity filtering scheme. Design examples are presented in order to show the performance improvement in terms of passband distortion and selectivity compared to other methods based on the traditional Kaiser-Hamming sharpening and the Chebyshev sharpening techniques recently introduced in the literature

Sistema de verificação de impressão digital baseado em DWT, extração de recursos de vários domínios e classificador de subespaço de conjunto

This paper describes a fingerprint verification system including preprocessing, Wavelet transform, feature extraction using multiple domains, and ensemble subspace discriminant classifier. The system is implemented in MATLAB using Wavelet Toolbox, Image Processing Toolbox, and Statistics and Machine Learning Toolbox. First, the motivation and novelty, followed by the review of the previous work, are presented. Next, all steps are described in detail. Three fingerprint databases from the literature are used. The proposed method’s performance is compared with state-of-the-art techniques based on different classifiers utilizing the accuracy metric. The proposed algorithm achieves high accuracy at 97.5% for the DB3-FVC2000 subset.Este documento describe un sistema de verificación de huellas dactilares que incluye preprocesamiento, transformada Wavelet, extracción de características utilizando múltiples dominios y clasificador discriminante subespacial de conjunto. El sistema se implementa en MATLAB utilizando Wavelet Toolbox, Image Processing Toolbox y Statistics and Machine Learning Toolbox. En primer lugar, se presenta la motivación y la novedad, seguido de la revisión del trabajo anterior. A continuación, se describen todos los pasos en detalle. Se utilizan tres bases de datos de huellas dactilares de la literatura. El rendimiento del método propuesto se compara con técnicas de última generación basadas en diferentes clasificadores que utilizan la métrica de precisión. El algoritmo propuesto logra una alta precisión del 97,5 % para el subconjunto DB3-FVC2000.Este documento descreve um sistema de verificação de impressão digital que inclui pré-processamento, transformada Wavelet, extração de recursos usando vários domínios e classificador discriminante de subespaço de conjunto. O sistema é implementado em MATLAB usando Wavelet Toolbox, Image Processing Toolbox e Statistics and Machine Learning Toolbox. A motivação e a novidade são apresentadas primeiro, seguidas pela revisão do trabalho anterior. Todas as etapas são descritas em detalhes a seguir. Três bancos de dados de impressões digitais da literatura são usados. O desempenho do método proposto é comparado com técnicas do estado da arte baseadas em diferentes classificadores que utilizam a métrica de precisão. O algoritmo proposto atinge uma alta precisão de 97,5% para o subconjunto DB3-FVC2000

Toward Early-Warning Detection of Gravitational Waves from Compact Binary Coalescence

Rapid detection of compact binary coalescence (CBC) with a network of advanced gravitational-wave detectors will offer a unique opportunity for multi-messenger astronomy. Prompt detection alerts for the astronomical community might make it possible to observe the onset of electromagnetic emission from (CBC). We demonstrate a computationally practical filtering strategy that could produce early-warning triggers before gravitational radiation from the final merger has arrived at the detectors.Comment: 16 pages, 7 figures, published in ApJ. Reformatted preprint with emulateap