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Orientation discrimination depends on spatial frequency
Vision Research, 1991Thresholds were measured for discriminating the orientation of sinusoidal gratings of varying spatial frequency, and found to decrease monotonically with increasing spatial frequency. For discrimination of high-contrast (10 times threshold) near-vertical gratings, thresholds ranged from about 1 deg at 0.04 c/deg to 0.5 deg at 0.2 c/deg, after which ...
BURR, DAVID CHARLES, S. A. WIJESUNDRA
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Masking of spatial-frequency discrimination
Journal of the Optical Society of America A, 1985Spatial-frequency discrimination thresholds were measured using the temporal two-alternative forced-choice procedure. A superimposed masker grating reduced discrimination threshold more than 20-fold when the spatial frequency of the masker was close to the test spatial frequency because moiré fringes provided a sensitive cue to the test grating's ...
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covariation between cortical magnification and preferred spatial frequency in human V1 measured using ...
Himmelberg, Marc +3 more
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Himmelberg, Marc +3 more
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Frequency-domain spatial modulation
2016 International Conference on Advanced Technologies for Communications (ATC), 2016Spatial modulation (SM) is a multiple-input multiple-output (MIMO) technique, which was introduced for wireless communication systems in which the number of transmit RF chains is smaller than the number of antennas. The basic principle in this technique is to select transmit antennas using information bits and transmit data symbols from these antennas.
Hernan F. Arrano +2 more
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2012
A certain number of scanned lines ( line images ) in a real-life image may display sinusoidal intensity profiles, but not all line images along the x or y axis are likely to contain sinusoidal or periodic intensity variations. Despite the nonperiodic nature of line images, and hence the whole image frame, the frequency spectrum of an image or an ...
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A certain number of scanned lines ( line images ) in a real-life image may display sinusoidal intensity profiles, but not all line images along the x or y axis are likely to contain sinusoidal or periodic intensity variations. Despite the nonperiodic nature of line images, and hence the whole image frame, the frequency spectrum of an image or an ...
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Observations on Spatial-Frequency Doubling
Perception, 1974The involvement of disparity detectors in the perception of spatial-frequency doubling in a flickering grating was tested by viewing the grating horizontally. Frequency doubling was unimpaired, and must therefore occur independently of disparity detection.
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Locus of spatial-frequency discrimination
Journal of the Optical Society of America A, 1987In standard frequency-discrimination experiments either the retinal spatial frequencies (cycles per degree) or the object spatial frequencies (real world) could be compared, because the retinal and object frequency differences are the same. Current models of spatial-frequency discrimination assume that observers compare the retinal frequencies.
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Spatial frequency discrimination at different orientations
Vision Research, 1989Hirsch and Hylton (1984) have reported a meridional anisotropy for spatial frequency discrimination with a periodicity containing both square and hexagonal components. We measured the difference limen for spatial frequency for sine-wave gratings whose orientations varied over a 180 deg range and whose nominal spatial frequency varied between 2.5 and 10.
D W, Heeley, B, Timney
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Space/spatial-frequency analysis based filtering
IEEE Transactions on Signal Processing, 2000Summary: Space-invariant filtering of signals that overlap with noise in both space and frequency can be inefficient. However, the signal and noise may be well separated in the joint space/spa\-tial-frequency domain. Then, it is possible to benefit from the application of space/spa\-tial frequency approaches.
Stanković, Ljubiša +2 more
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Contrast and Spatial Frequency
Scientific American, 1974F W, Campbell, L, Maffei
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