Optical implementation of the fractional Hilbert transform for two-dimensional objects

1997 ◽  
Vol 36 (26) ◽  
pp. 6620 ◽  
Author(s):  
A. W. Lohmann ◽  
E. Tepichín ◽  
J. G. Ramírez
1999 ◽  
Author(s):  
M. Torres ◽  
Eduardo Tepichin-Rodriguez ◽  
Adolf W. Lohmann ◽  
David Sanchez ◽  
Gustavo Ramirez Zabaleta

1996 ◽  
Vol 21 (4) ◽  
pp. 281 ◽  
Author(s):  
Adolf W. Lohmann ◽  
David Mendlovic ◽  
Zeev Zalevsky

2017 ◽  
Vol 39 (3) ◽  
pp. 658-688 ◽  
Author(s):  
POLONA DURCIK ◽  
VJEKOSLAV KOVAČ ◽  
KRISTINA ANA ŠKREB ◽  
CHRISTOPH THIELE

We study double ergodic averages with respect to two general commuting transformations and establish a sharp quantitative result on their convergence in the norm. We approach the problem via real harmonic analysis, using recently developed methods for bounding multilinear singular integrals with certain entangled structure. A byproduct of our proof is a bound for a two-dimensional bilinear square function related to the so-called triangular Hilbert transform.


Geophysics ◽  
1996 ◽  
Vol 61 (1) ◽  
pp. 264-272 ◽  
Author(s):  
Arthur E. Barnes

The ideas of 1-D complex seismic trace analysis extend readily to two dimensions. Two‐dimensional instantaneous amplitude and phase are scalars, and 2-D instantaneous frequency and bandwidth are vectors perpendicular to local wavefronts, each defined by a magnitude and a dip angle. The two independent measures of instantaneous dip correspond to instantaneous apparent phase velocity and group velocity. Instantaneous phase dips are aliased for steep reflection dips following the same rule that governs the aliasing of 2-D sinusoids in f-k space. Two‐dimensional frequency and bandwidth are appropriate for migrated data, whereas 1-D frequency and bandwidth are appropriate for unmigrated data. The 2-D Hilbert transform and 2-D complex trace attributes can be efficiently computed with little more effort than their 1-D counterparts. In three dimensions, amplitude and phase remain scalars, but frequency and bandwidth are 3-D vectors with magnitude, dip angle, and azimuth.


1990 ◽  
Vol 133 (1) ◽  
pp. 117-126 ◽  
Author(s):  
N. Sundararajan ◽  
I. Arun Kumar ◽  
N. L. Mohan ◽  
S. V. Seshagiri Rao

Sign in / Sign up

Export Citation Format

Share Document