1. Radar backscattering measurements of paddy rice field using L, C and X-band polarimetric scatterometer
ISRS 2007

2. Contents 1
Background 2
Material and Methods 3
Results 4
Conclusion

3. Background
Microwave radar can penetrate cloud cover regardless of weather condition
Ground-based polarimetric scatterometer has advantage of monitoring crop
conditions with full polarization and various frequencies
Plant parameters such as LAI, biomass, plant height are highly correlated with
backscattering coefficients
ENVISAT SAR data (5.3 GHz, hh-, hv-polarizations, and incidence angles
between 28.5° and 40.9°) to monitor rice growth and compared the data with
simulation results (Le Toan et al, 1997)
RADARSAT data (5.3 GHz, hh-polarization, and incidence angles between
36° and 46°) was analyzed for monitoring the rice growth in Korea (Hong et al,2000)

4. Objective
To measure backscattering coefficients of paddy rice using L, C,
X-bands scatterometer system during the growth period
Relationship between backscattering coefficients and rice growth
variables with full polarization and various angles

5. - An experimental field at NIAST, Suwon, korea.
Study site
- An experimental field at NIAST, Suwon, korea.
Testing varieties : Chuchoungbyeo
The size field : 660m2

6. Consist of polarimetric scatterometer system
Vector Network Analyzer
- Agilent 8720D, 20MHz ~ 20GHz
Calibration Kit
Network Analyzer
Calibration kit

7. Dual polarimetric horn
Materials and Methods
Specification of the scatterometer system
Specification
L-Band
C-Band
X-Band
Center frequency
1.27GHz
5.3GHz
9.65GHz
Bandwidth
0.12GHz
0.6GHz
1GHz
Number of frequency points
201
801
1601
Antenna type
Dual polarimetric horn
Antenna gain
12.4dB
20.1dB
22.4dB
Polarization
HH, VV, HV, VH
Incident angle
20°~60°
Platform height
4.16m

8. Backscattering coefficients (by applying radar equation)
Consist of polarimetric scatterometer system
Dual Polarimetric Horn Antenna
L-band
C-band
X-band
Backscattering coefficients (by applying radar equation)

9. Polarimetric scatterometer system

10. Results angle for the L-band Incident angle: 25 Incident angle: 30
Temporal variations of backscattering coefficients at polarization and incident
angle for the L-band
Incident angle: 25
Incident angle: 30
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Incident angle: 35
Incident angle: 40
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11. Results angle for the L-band Incident angle: 45 Incident angle: 50
Temporal variations of backscattering coefficients at polarization and incident
angle for the L-band
Incident angle: 45
Incident angle: 50
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Incident angle: 55
Incident angle: 60
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12. Results angle for the C-band Incident angle: 25 Incident angle: 30
Temporal variations of backscattering coefficients at polarization and incident
angle for the C-band
Incident angle: 25
Incident angle: 30
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Incident angle: 35
Incident angle: 40
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13. Results angle for the C-band Incident angle: 45 Incident angle: 50
Temporal variations of backscattering coefficients at polarization and incident
angle for the C-band
Incident angle: 45
Incident angle: 50
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Incident angle: 55
Incident angle: 60
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14. Results angle for the X-band Incident angle: 25 Incident angle: 30
Temporal variations of backscattering coefficients at polarization and incident
angle for the X-band
Incident angle: 25
Incident angle: 30
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Incident angle: 35
Incident angle: 40
Heading
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15. Results angle for the X-band Incident angle: 45 Incident angle: 50
Temporal variations of backscattering coefficients at polarization and incident
angle for the X-band
Incident angle: 45
Incident angle: 50
Heading
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Incident angle: 55
Incident angle: 60
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16. Results
Correlation between L-band backscattering coefficients and rice growth parameters
during growth season VV HH HV
Incident angle
Plant
height
LAI
Tfw
(g/m2)
Tdw 20
-0.93
-0.81
-0.90
-0.87
-0.56
-0.20
-0.37
-0.32
0.21
0.38
0.29
0.32 25
-0.53
0.24
0.44
0.76
0.85
0.81 30
-0.01
0.28
0.15
0.18
-0.39
-0.38
-0.42
-0.40
0.91
0.77
0.82 35
-0.49
-0.63
-0.58
-0.62
0.40
0.25
0.31
0.89
0.71
0.80
0.78 40
0.58
0.70
0.68
0.74
0.73
0.72
0.86 45
0.92
0.87
0.94
0.90 50
0.63
0.75
0.97
0.98 55
0.62
0.93
0.95
0.88 60
0.79

17. Results
Correlation between C-band backscattering coefficients and rice growth parameters
during growth season VV HH HV
Incident angle
Plant
height
LAI
Tfw
(g/m2)
Tdw 20
-0.94
-0.74
-0.84
-0.83
-0.67
-0.76
-0.75
0.81
0.67
0.74
0.71 25
0.72
0.75
0.48
0.46
0.96
0.92
0.95 30
0.82
0.78
0.86
0.83
0.84
0.85
0.94 35
0.70
0.68
0.93
0.90
0.89
0.91 40
0.38
0.55
0.50
0.87 45
0.64
0.56
0.58
0.88 50
0.76
0.73 55 60
0.44
0.43

18. Results
Correlation between X-band backscattering coefficients and rice growth parameters
during growth season VV HH HV
Incident angle
Plant
height
LAI
Tfw
(g/m2)
Tdw 20
0.26
0.41
0.32
0.68
0.63
0.64
0.80
0.83
0.82 25
0.62
0.70
0.67
0.72
0.66
0.73
0.74 30
0.46
0.57
0.54
0.52
0.84
0.65
0.75
0.69 35
0.50
0.61
0.81
0.86
0.85
0.71
0.79 40
0.43
0.55
0.56 45
0.33
0.45
0.42
0.40
0.76 50
0.23
0.29
0.28
0.24
0.77 55
-0.10
-0.20
-0.13
-0.18 60
-0.25
-0.44
-0.36
-0.41
0.78

19. Results
Correlation between L-, C-, X-band backscattering coefficients and rice growth
parameters (grain dry weight) during growth season
L-band
C-band
X-band
Incident angle VV HH HV 20
-0.96
-0.85
-0.64
-0.50
-0.19
0.26
-0.54
-0.05
0.10 25
-0.97
-0.74
0.06
-0.39
-0.70
-0.33
0.35
0.56 30
-0.78
0.53
-0.55
-0.38
0.51
0.31
-0.45 35
0.43
0.72
-0.81
-0.32
0.27
0.60
-0.30
-0.40 40
0.61
0.40
0.66
-0.22
-0.86
0.64
-0.36 45
0.75
0.23
0.63
-0.83
-0.13
0.78
0.39
0.45 50
0.71
-0.67
0.29
-0.16
-0.52
0.93
0.55
0.81 55
0.58
-0.29
0.07
0.17
-0.77
0.89
0.70
0.87 60
0.30
0.18
-0.10
0.67
0.88
0.74

20. Conclusions
The temporal variations of the backscattering coefficients of the rice crop at L-, C-, X-
band during rice growth period
VV-polarized backscattering coefficients higher than hh-polarized backscattering
coefficients in early rice growth stage
HH-polarized backscattering coefficients higher than vv-polarized backscattering
coefficients after panicle initiation stage
Biomass was correlated with L-band HH-polarization at large incident angle
LAI was highly correlated with the C-band HH- and cross-polarizations
X-band were poorly correlated with LAI and biomass
Grain weight was correlated with backscattering coefficient with X-band (at large angle,
vv-polarization)

21. Thank You !