Results 211 to 220 of about 79,703 (263)

On the Need for Signal-Coherent Watermarks

IEEE Transactions on Multimedia, 2006
Digital watermarking has been introduced in the 1990s as a complementary technology for copyright protection. In an effort to anticipate hostile behavior of adversaries, the research community is constantly introducing new attacks to benchmark watermarking systems. In this paper, we present a generic attack strategy based on block replacement.
Gwenaël J. Doërr, Jean-Luc Dugelay, Darko Kirovski   +2 more
openaire   +1 more source

Signal estimation and coherence: publisher’s note

Optics Letters, 2021
This publisher’s note contains a correction to Opt. Lett. 46 , 5409 ( 2021 ) 10.1364/OL.439197 .
Laura, Ares, Alfredo, Luis
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Evolutionary Coherence of Nonstationary Signals

IEEE Transactions on Signal Processing, 2008
Coherence is a widely used measure for characterizing linear dependence between a pair of signals. For nonstationary signals, the autospectrum, cross spectrum, and coherence between signals may evolve over time. A standard approach is to divide the signals into overlapping blocks of fixed width and then smooth (over frequency) the periodogram matrix at
Hernando Ombao, Sébastien Van Bellegem
openaire   +1 more source

Generalized coherence (signal detection)

ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing, 2003
The authors introduce a test for detecting the presence of a common signal on M noisy channels that generalizes a popular technique using the magnitude-squared coherence (MSC) estimate for detecting a common signal on two channels. The basis of this test is the generalized coherence estimate, a statistic involving the normalized M*M Gram matrix ...
Herbert Gish, Douglas Cochran
openaire   +1 more source

Signal subspace sphericity and inter-signal coherence-MUSIC induces inter-signal coherence

[1991] Conference Record of the Twenty-Fifth Asilomar Conference on Signals, Systems & Computers, 2002
The role and importance of signal subspace sphericity are discussed. Using signal subspace arguments with the true correlation matrix, it is shown that MUSIC effectively induces intersignal coherence due to its requirement for subspace sphericity. It is also shown in the finite data case that some commonly used direction finding methods yield results ...
D.A. Linebarger, R.D. DeGroat
openaire   +1 more source

Coherent signal - subspace processing in a sector

Twenty-Third Asilomar Conference on Signals, Systems and Computers, 1989., 1989
The determination of the number of wideband signals impinging on a passive sensor array in the form of multiple groups (clusters), and the estimation of their directions of arrival is addressed. The idea of preprocessing by a set of orthogonal beamformers for dimensionality reduction is used to simplify wideband processing.
Antonios Bassias, Mostafa Kaveh
openaire   +1 more source

Modeling the Coherence of Scattered Signals of Opportunity

IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, 2019
The reflection of radar echoes collected under both monostatic and bistatic configurations generally undergoes losses of coherence. These can be affected by many factors, depending on both the system features and the illuminated surface, and it should be properly considered for an accurate characterization of the scattering phenomenon.
Comite D., Dente L., Guerriero L., Pierdicca N.   +3 more
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Coherent signal analyzer

2020
Systems and methods for analyzing a characteristic of a transmitter, a receiver, or a propagation channel are disclosed. At least one receiver signal resulting from at least one transmitter signal that has propagated through a propagation channel can be obtained.
PRATT THOMAS G, MUELLER JEFFREY G, KOSSLER ROBERT D   +2 more
openaire   +2 more sources

Generalized Coherence-Based Signal Enhancement

ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2020
This contribution presents a novel approach for coherence-based signal enhancement. An estimator for the coherent-to-diffuse ratio (CDR) is devised, which exploits the concept of generalized magnitude coherence and thus, unlike common state-of-the-art schemes, can simultaneously take advantage of more than two microphones.
Heinrich W. Löllmann, Andreas Brendel, Walter Kellermann   +2 more
openaire   +1 more source

Coherent Detection Signal-to-Noise

Applied Optics, 1975
General equations are derived for the signal-to-noise ratio of a coherent (heterodyne) receiver in terms of the distribution functions of the signal and local oscillator fields and the size and shape of the detector. The optimum local oscillator field distribution is identical to the signal field distribution over the detector surface. The special case
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