Results 241 to 250 of about 103,159 (268)

Coherent array imaging with sparse arrays

Proceedings., International Conference on Image Processing, 2002
For coherent, phased-array imaging systems, sparse arrays are often used in which the aperture is not completely filled by the array. Often, the data that are not collected by the array are set to zero and an image is obtained through a straight-forward Fourier inversion.
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Sparse Array Signal Processing

2023
This dissertation details three approaches for direction-of-arrival (DOA) estimation or beamforming in array signal processing from the perspective of sparsity. In the first part of this dissertation, we consider sparse array beamformer design based on the alternating direction method of multipliers (ADMM); in the second part of this dissertation, the ...
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Maximally economic sparse arrays and cantor arrays

2017 IEEE 7th International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), 2017
Sparse arrays, where the sensors are properly placed with nonuniform spacing, are able to resolve more uncorrelated sources than sensors. This ability arises from the property that the difference coarray, defined as the differences between sensor locations, has many more consecutive integers (hole-free) than the number of sensors.
Liu, Chun-Lin, Vaidyanathan, P. P.
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Sonar array signal processing for sparse linear arrays

ISSPA '99. Proceedings of the Fifth International Symposium on Signal Processing and its Applications (IEEE Cat. No.99EX359), 2003
Acoustic signals which propagate through the ocean have wavefronts which can differ significantly from the "planar wavefronts" assumed in array signal processing. In this paper we investigate the performance of the the minimum variance distortionless response (MVDR) beamformer and the previously introduced Fourier integral method (FIM), when applied to
I.S.D. Solomon, A.J. Knight, M.V. Greening   +2 more
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Direct-MUSIC on sparse arrays

2012 International Conference on Signal Processing and Communications (SPCOM), 2012
Nested and coprime arrays are sparse arrays which can identify O(m2) sources using only m sensors. Systematic algorithms have recently been developed for such identification. These algorithms are traditionally implemented by performing MUSIC or a similar algorithm in the difference-coarray domain.
Vaidyanathan, P. P., Pal, Piya
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Sparse Optical Phased Array Design

2019 IEEE 16th International Conference on Group IV Photonics (GFP), 2019
We propose a scalable, low fill factor, optical phased array design based on sparse arrays, relaxing the sub-wavelength antenna pitch requirement for sidelobe suppression, achieving significantly lower beamsteering power consumption than a uniform array.
Francis Smith, Wuxiucheng Wang, Hui Wu
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Autofocus for sparse array imaging

SPIE Proceedings, 2010
If sparse arrays are attached to structures for the purposes of structural health monitoring it is likely that there will be variation in the placement of the sensors, resulting in deviation from the assumed locations. In addition, poor knowledge of the material through which the signals are propagating can result in the use of incorrect velocities ...
Anthony J. Croxford, Alan J. Hunter
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Sparse sensing with coprime arrays

2010 Conference Record of the Forty Fourth Asilomar Conference on Signals, Systems and Computers, 2010
Coprime sampling has, in the past, been used for signal processing applications such as range and doppler improvement in radar, and for identifying sinusoids in noise. This paper considers a coprime pair of samplers in space or time from the point of view of the difference coarray, which is key to the increased freedom available for processing with ...
P. P. Vaidyanathan, Piya Pal
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Bilinear problems and sparse arrays

The Journal of the Acoustical Society of America, 2017
Inverse problems in imaging with sensor arrays often involve estimation of desired parameters (associated with targets or sources) in presence of undesired quantities such as modeling and calibration errors, or uncertainties in accurate modeling of the propagation medium.
Ali Koochakzadeh, Piya Pal
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Sparse Arrays for SatCom Applications

31st AIAA International Communications Satellite Systems Conference, 2013
The paper provides a short overview on recent ESA developments on array antenna architectures for satellite antennas generating a multiple spot beams coverage with a single aperture. In particular, solutions based on direct radiating arrays, discrete lens arrays, and arrays magnified by confocal reflectors will be discussed.
Piero Angeletti, Giovanni Toso
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