International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B1. Istanbul 2004
here, «1
| the DA
outh
f the
rent
urier
ents,
AB 1005 0 5 10, 16
Figure 1. Differential interferogram (above) and differential -
the atmospheric delay signals of Shanghai study region (below). A 30 8 40 5 060 5. 1 © 35
Figure 3. Differential interferogram (above) and differential
atmospheric delay signals of New South Wales study region
and (below). A square region of 20 km x 20 km is chosen for
square region of 50 km x 50 km is chosen for further study.
It is further study.
| the
The
For
dis Hiterferoeram Master Slave B | h,,
luce = (ERSI) (ERS2) (m) | (m)
1t of Shanghai 19/02/1996 | 20/02/1996 | -44 | 216
| the Hong Kong 18/03/1996 | 19/03/1996 | 100 | 95
| an New South Wales | 29/10/1995 | 30/10/1995 | -49 194
r of
racy | Table 1 Summary of the tandem pairs.
less
the
3 Anisotropy of Atmospheric Signal
y of 3.1 The Radon Transform
| CO-
al | Radon transform is the projection of image intensities along
| by radial lines at a specified angle. A single Radon transform is a
els | mapping from two dimensions to one dimension where the
; 40 image intensities collapse to a profile. It is therefore a tool to
will | investigate anisotropy in images since systematic intensity
un | variantions in a particular direction will be significantly visible
ram | as a profile. The definition of Radon transform is (Bracewell,
eful 1995)
ures |
tis, |
id | RAS (x)= [ [ re yXé(r — xcos8— ysinQydxdy (1)
pe
and ^ - . . . ~~ E .
where f(x, y)is the image intensity, 6 is the profile direction
(counterclockwise from horizontal), and Ó is the Dirac delta
atmospheric delay signals of Hong Kong study region (below). function. When applied to a discrete image d, , the Radon
À square region of 12 km x 12 km is chosen for further study.
Figure 2. Differential interferogram (above) and differential
transform becomes
