슬라이드 1 - Kangwon
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Transcript 슬라이드 1 - Kangwon
Polarimetric Characteristics of Fully Polarization SAR Image
Observed by Ground-Based SAR System
Moon-Kyung Kang1*, Kwang-Eun Kim2, Hoonyol Lee3, Seong-Jun Cho4 and Jae-Hee Lee5
1,2,4,5 Korea
Institute of Geoscience and Mineral Resources, Daejeon, Republic of Korea, *[email protected]
3,5 Department of Geophysics, Kangwon National University, Suncheon, Republic of Korea
INTRODUCTION
RESULTS
Ground-Based SAR (GB-SAR) systems
monitoring tools for agriculture, terrain mapping, man-made structures
ground surface deformation detection and displacement measurement
dams, bridges, and so on
using SAR interferometric techniques.
SAR Polarimetry Technique
for analysis of more detailed physical and biophysical features of various surface
target
understanding of scattering characteristics about a single or distributed targets.
Many researchers have been interested in classification, decomposition, and modelling
of polarimetric SAR data in recent literature.
The objective behind efforts is better understanding about the scattering
mechanism that give rise to the polarimetric characteristics seen in SAR image data.
The purpose of this paper
This work was focused on application study of the developed GB-SAR system based
on SAR polarimetry techniques as a preliminary study.
analyzing the dominant scattering properties about different surface targets such as
trees, grasses, a human-made structure, and several permanent scatterers
using H/A/Alpha polarimetric decomposition algorithms.
Alpha parameter
α-> 0 : a single scattering (rough surface)
α -> 45 : volume scattering
α -> 90 : double-bounce scattering
0
Entropy (H) parameter
H=0 : a pure target
H=1 : truly a random noise process
90
0
1
An example of Wishat-H/A/Alpha classification (#_41)
METHODOLOGY
GB-SAR System
1 2 3 4 5 6 7 8
Test site
Korea Institute of Geoscience and
Mineral Resources (KIGAM) field
for operation and performance test of
GB-SAR system
Five permanent scatterers
Measurement Date: 3-5 November, 2008
(a) Wishart-H/Alpha classification
1 2 3 4 5 6 7 8 9 10 11 12 13 1415 16
(c) Wishart-H/A/Alpha classification
5.3 GHz (C-band)
Range bandwidth
600 MHz
IF BW
1 KHz
Number of point
1601
Power
VNA 0 dBm, Amp 33 dBm
Azimuth step
5 cm
Azimuth length
5m
Polarization
HH, HV, VH, VV
Used software
SAR focusing processing: ‘gbsar’ processor (by Kangwon National University)
PolSAR processing: ‘PolSARpro’ open software package
(http://envisat.esa.int/polsarpro)
The main PolSAR processing
H/A/Alpha decomposition and analysis
Unsupervised Wishart – H/A/Alpha classification
RESULTS
Ps_1 Ps_2
Ps_3
The dominant colors over grass and
trees areas
-> pink, white, green, blue
white -> equal amplitude over all
polarimetric channel
green -> a dominant HV component
pink-magenta -> VV, HH > HV
5 permanent scatterers
white and magenta
Ps_4
Ps_5
Grass Area
Lexicographic (Sinclair) color coded
image (R: VV, G: HV, B: HH) at #_41
Temperature (℃)
Temperature (℃)
(a)
20
15
10
5
0
3
#_155
Phase Variation (ps-1)
#_7
#_80
1
0
1
5
9
13
17
21
25
29
33
37
41
45
49
53
57
61
65
69
73
77
81
85
89
93
97
101
105
109
113
117
121
125
129
133
137
141
145
149
153
157
Variation (radian)
2
2008/11/03 13:04 ~ 2008/11/05 16:52
(b)
-1
-2
-3
#_56
Measurement Number
1 2 3 4 5 6 7 8 9 10 11 12 131415 16
(d) Wishart-H/A/Alpha1 classification
Test site (KIGAM)
Image Processing
25
(b) Wishart-H/Alpha1 classification
Temporal variation: Wishart-H/A/Alpha1 classification Results
Center frequency
Trees Area
1 2 3 4 5 6 7 8
HH_pha
#_130
HV_pha
VH_pha
VV_pha
(a) atmosphere temperature
variation graph during entire
measurement period
(b) phase variation graph of
HH, HV, VH and VV
polarizations at a permanent
scatterer (ps_1)
(a) and (b) graphs show
similar distribution
1 2 3 4 5 6 7 8 9 10 11 12 13 1415 16
1 2 3 4 5 6 7 8 9 10 11 12 13 1415 16
(a) #_7
1 2 3 4 5 6 7 8 9 10 11 12 13 1415 16
(a) #_56
1 2 3 4 5 6 7 8 9 10 11 12 13 1415 16
(c) #_80
(d) #_130
CONCLUSIONS
The objective of this study has been to assess a geophysical application of fully
polarimetric SAR data measured by the GB-SAR system in order to extracting relevant
information about surface scattering properties.
From the classification results, we can consider that the dominant scattering property
of different surface targets such as natural or man-made targets varies depending on
target’s material types and their environmental conditions.
It is expected that GB-SAR system will be a convenient tool for measurement and
analysis of polarimetic properties for various target on the Earth.
ACKNOWLEDGEMENTS
This research was supported by a grant (07KLSGC03) from Cutting-edge Urban
Development - Korean Land Spatialization Research Project funded by Ministry of Land,
transport and Maritime Affairs of Korean government.
REFERENCES
Lee, J.-S. and Pottier, E., 2009. Polarimetric Radar Imaging From Basics to Applications, CRC Press.
Lee, H., Cho, S.-J., Sung, N.-H., and Kim, J.-H., 2007a. Development of a GB-SAR (I): System Configuration
and Interferometry, Korean Journal of Remote Sensing, 23(4), pp. 237-245.
Lee, H., Cho, S.-J., Sung, N.-H., and Kim, J.-H., 2007b. Development of a GB-SAR (II): Focusing Algorithms,
Korean Journal of Remote Sensing, 23(4), pp. 247-256.