1. 이훈열, 조성준, 성낙훈 강원대학교 지구물리학과 한국지질자원연구원 지반안전연구부
대한원격탐사학회 2007 춘계학술대회 3월 30일 대전 대덕컨벤션타운
GB-SAR 시스템의 개발과 응용
이훈열, 조성준, 성낙훈
강원대학교 지구물리학과
한국지질자원연구원 지반안전연구부

2. Contents Introduction GB-SAR System SAR Focusing and Interferometry
Applications
Conclusion

3. Introduction GB-SAR: Ground-Based Synthetic Aperture Radar
Imaging Radar
Azimuth aperture synthesis
Ground-Based
Fairly versatile system configuration
Multiple frequency (L, C, X, Ku, Ka, etc)
Full Polarization (VV, VH, HV, HH)
Ultimate SAR focusing
Zero Doppler centroid (stationary vehicle during Tx/Rx)
Accurate estimation of Doppler rate from geometry
Topography Mapping: Cross-Track InSAR or Delta-K InSAR
Surface Motion: Zero-baseline and short atmospheric path for Temporal Coherency, DInSAR and PSInSAR
Useful for new SAR concept design
Previous Works
LISA (EU) for Avalanche and landslide monitoring
Other laboratory or field tests (UK, Japan)

4. GB-SAR System

5. System Configuration

6. SAR Focusing Algorithms
Advantange
Disadvantage
Usage
Range-Doppler or ω-k
Widely used for SAR
Memory inefficiency for partial-focusing
Near Range
(full-focusing)
Deramp-FFT
Efficient in memory and CPU time
Distortion in near range
Far Range
(partial-focusing)
Time Domain
Exact everywhere
Time consuming
Everywhere

7. GB-SAR Resolutions Range resolution: (a) Full Focusing
(b) Partial Focusing

8. GB-InSAR Configuration
DInSAR
Cross-Track InSAR
Delta-K InSAR
Cross-Track and Delta-K InSAR
DInSAR with range change
Cross-Track InSAR

9. GB-SAR Interferometry
Change
Phase Difference
Range phase ramp
Sensitivity
DInSAR
Range
none
Cross-Track InSAR
Vertical baseline
Height
Delta-K InSAR
Frequency shift
Cross-Track and Delta-K InSAR
and

10. KIGAM Roof-Top Test T1 Range: Center frequency=5.3GHz Bandwidth=200MHz
Sample=1601
Power=33dBm (2W)
Azimuth:
Scan length=5m
Step=5cm
Sample=101
T2: Temporal baseline of 20minutes (DInSAR)
T3: Spatial baseline of -30cm vertical (InSAR DEM)
T4: Frequency shift of -10MHz (Delta-K InSAR)

12. Image Area

13. VV T1

14. VH T1

15. HH T1

16. DInSAR (T2-T1) VV

17. Cross-Track InSAR (T3-T2)VV

18. Delta-K InSAR (T4-T3) VV VV

19. Cross-Track and Delta-K InSAR (T4-T2)VV VV VV

20. Automatic Acquisition with 2cm Step, 2007. 3. 19 7:22pm- 4:20am, A1~A9VV HH

21. Phase Errors Ideal Case A6-A5, HH Azimuth scan shift of 2cm. A9-A1, HH
Range System Shift of 2mm

22. Conclusion We made a SAR system.
A GB-SAR system was developed, tested, and waiting for applications.
Optimal GB-SAR focusing algorithms were tested.
Cross-Track and Delta-K InSAR were tested.
DInSAR or PSInSAR were tested: Phase stability of 1° (0.1mm range) was achieved for several hours for stable reflectors, rendering phase change of 10 ° meaningful (1mm range accuracy for DInSAR).
GB-SAR can be used for various applications such as:
Safety monitoring of natural or anthropogenic structures
Microwave backscattering properties of target
New SAR system concept design
More robust GB-SAR system optimized to a specific application will be developed.

23. Thank You