1,114,787 research outputs found
High-resolution spectral analysis
Analyzer extends the range and resolution of a digital spectrum analyzer without placing stringent stability requirements on the sampling rate. It compares an unknown signal with a stable frequency standard
Spectral Analysis Program (SAP)
Program eliminates or reduces time-consuming aspects of computation of power spectrum for high-frequency communication system. This program was written in FORTRAN IV for UNIVAC 1230 or 1108 computer
Factor Analysis for Spectral Estimation
Power spectrum estimation is an important tool in many applications, such as
the whitening of noise. The popular multitaper method enjoys significant
success, but fails for short signals with few samples. We propose a statistical
model where a signal is given by a random linear combination of fixed, yet
unknown, stochastic sources. Given multiple such signals, we estimate the
subspace spanned by the power spectra of these fixed sources. Projecting
individual power spectrum estimates onto this subspace increases estimation
accuracy. We provide accuracy guarantees for this method and demonstrate it on
simulated and experimental data from cryo-electron microscopy.Comment: 5 pages, 3 figures; 12th International Conference Sampling Theory and
Applications, July 3-7, 2017, Tallinn, Estoni
Spectral Analysis of Percolation Hamiltonians
We study the family of Hamiltonians which corresponds to the adjacency
operators on a percolation graph. We characterise the set of energies which are
almost surely eigenvalues with finitely supported eigenfunctions. This set of
energies is a dense subset of the algebraic integers. The integrated density of
states has discontinuities precisely at this set of energies. We show that the
convergence of the integrated densities of states of finite box Hamiltonians to
the one on the whole space holds even at the points of discontinuity. For this
we use an equicontinuity-from-the-right argument. The same statements hold for
the restriction of the Hamiltonian to the infinite cluster. In this case we
prove that the integrated density of states can be constructed using local data
only. Finally we study some mixed Anderson-Quantum percolation models and
establish results in the spirit of Wegner, and Delyon and Souillard.Comment: 19 pages, LaTeX 2e. See also preprint 04-326 on mp_arc. To appear in
a slightly different version in "Mathematische Annalen", see the DO
Data analysis techniques: Spectral processing
The individual steps in the data processing scheme applied to most radars used for wind sounding are analyzed. This processing method uses spectral analysis and assumes a pulse Doppler radar. Improvement in the signal to noise ratio of some radars is discussed
Spectral analysis for nonstationary audio
A new approach for the analysis of nonstationary signals is proposed, with a
focus on audio applications. Following earlier contributions, nonstationarity
is modeled via stationarity-breaking operators acting on Gaussian stationary
random signals. The focus is on time warping and amplitude modulation, and an
approximate maximum-likelihood approach based on suitable approximations in the
wavelet transform domain is developed. This paper provides theoretical analysis
of the approximations, and introduces JEFAS, a corresponding estimation
algorithm. The latter is tested and validated on synthetic as well as real
audio signal.Comment: IEEE/ACM Transactions on Audio, Speech and Language Processing,
Institute of Electrical and Electronics Engineers, In pres
Power spectral density analysis
Equations for power spectral density function, and for root mean square of power spectral density functio
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