Results 241 to 250 of about 3,070,422 (295)

Direction finding with a rotating antenna

2012 20th Signal Processing and Communications Applications Conference (SIU), 2012
Finding the direction of the emitters is a problem to be solved in many areas. One of the methods used for that purpose is that using a rotating directional antenna and obtaining the direction estimate by processing the measured signal amplitudes. Direction estimation, in principle, is based on the own antenna pattern modulation on the measured signal.
Berkin Yildirim, Aydin Bayri, Gokhan Gok
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Finding a long directed cycle

ACM Transactions on Algorithms, 2008
Consider a digraph with n vertices. For any fixed value k , we present linear- and almost-linear-time algorithms to find a cycle of length ≥ k , if one exists. We also find a cycle that has length ≥ log n /log log n in ...
Harold N. Gabow, Shuxin Nie
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A parametric direction finding technique

ICASSP '87. IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005
The fundamental signal model for narrowband direction finding - the propagation of several sinusoidal planar wavefronts in a medium containing an array of sensors with additive Gaussian noise present - is assumed implicitly in most high resolution beamforming algorithms.
Darel A. Linebarger, Don H. Johnson
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Finding Dominators in Directed Graphs

SIAM Journal on Computing, 1974
This paper describes an algorithm for finding dominators in an arbitrary directed graph. The algorithm uses depth-first search and efficient algorithms for computing disjoint set unions and manipulating priority queues to achieve a time bound of $O(V\log V + E)$ if V is the number of vertices and E is the number of edges in the graph.
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A robust estimator for direction finding

[Proceedings] ICASSP 91: 1991 International Conference on Acoustics, Speech, and Signal Processing, 1991
Among high-resolution direction-of-arrival (DOA) estimators, it is known that the maximum likelihood estimation (MLE) has the most desirable performance in resolution. However, when the SNR falls below a certain threshold, its performance degrades considerably.
Qiang Wu 0006, Kon Max Wong
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Decoupled direction finding: detection

Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 (Cat. No.98CH36181), 2002
Antenna arrays are likely to be an important feature of future mobile communication systems. With an antenna array, mobile users can be separated by a spatial filtering procedure allowing several users on the same carrier frequency. The uplink part (mobile to base) not only can, but is better solved without using any spatial knowledge in terms of ...
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Finding the direction of a sound

The Journal of the Acoustical Society of America, 1986
An arrangement for finding the direction of a sound in a medium has a thin shell structure having a circular symmetry. The structure can flex in response to incident sound energy from the medium to perturb the form of the structure. A membrane of a piezo-electric material with an anisotropic piezo-electric response to distortion is arranged to be ...
Philip G. Harper, Stuart I. Jardine, Andrew J. Quinn, David M. Treherne   +3 more
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Robust direction finding

Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004., 2005
This paper considers the problem of estimating directions of arrival (DOAs) from sensor-array data when the positions of the sensors are not precisely known. The proposed algorithm is an extension of a previously developed approach based on weighted subspace fitting.
Vaccaro, Richard J., Owsley, Norman L.
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Direction findings on whistlers

Journal of Geophysical Research, 1959
Efforts to study the direction of arrival and polarization of whistlers have led to confusion, presumably because of the complexity of the signals and their transient behavior. This letter describes one technique which shows promise in that it has given results on the direction of some whistlers.
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Finding the illuminant direction

Journal of the Optical Society of America, 1982
Shading is important for estimation of three-dimensional shape from the two-dimensional image, for instance, for distinguishing between the smooth occluding contour generated by the edge of a sphere and the sharp occluding contour generated by the edge of a disk.
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