Engineering geophysics Agenda Introduction of GBSAR Concept of

Engineering geophysics Agenda • • • 연구배경 및 목적 Introduction of GB-SAR Concept of Arc. SAR Hardware configuration of Arc. SAR Imaging geometry of Arc. SAR 향후 추진 계획 KIGAM

Engineering geophysics • GB-SAR: Ground-Based Synthetic Aperture Radar – 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 In. SAR or Delta-K In. SAR • Surface Motion: Zero-baseline and short atmospheric path for Temporal Coherency, DIn. SAR and PSIn. SAR • Useful for new SAR concept design KIGAM

Engineering geophysics SAR Focusing – Point Target azimuth range £original £After KIGAM migration £After range compression azimuth compression

Engineering geophysics State of the art of GB-SAR • • LISA SAR (Italy) GB-POLIn. SAR (Australia) GB-SAR (Japan) Mobile SAR (Korea) KIGAM

Engineering geophysics GB-SAR(KIGAM-KNU) DIn. SAR tested: Phase stability of 1° (0. 1 mm range) was achieved for several hours for stable reflectors, rendering phase change of 10 ° to be assured (1 mm accuracy). PSIn. SAR displacement measurement: R 2=0. 9999 achieved. 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 KIGAM

Engineering geophysics KIGAM System Configuration

Engineering geophysics KIGAM GB-SAR System(KIGAM-KNU)

Engineering geophysics SAR Focusing Algorithms Advantage Disadvantage Usage Range-Doppleror ω-k Widely used for SAR Memory inefficiency for partial-focusing Near Range (full-focusing) Deramp-FFT Efficient in Far Range Distortion in near memory and CPU range (partial-focusing) time Time Domain Exact everywhere Time consuming KIGAM Everywhere

Engineering geophysics AWS Arc. SAR Concept design AWS KIGAM

Engineering geophysics GB-SAR vs Arc. SAR GB-SAR Arc. SAR(World first) Scan Type Linear Arc Scan Load Heavy Light RF stability Stable Resolution Higher due to wider azimuth bandwidth Installation Ground-fixed Automobile: higher mobility Phase repeatability High Low (Still now) SAR focusing Conventional New DIn. SAR change detection Emergency Mapping (Still now) DIn. SAR change detection (future) Major application KIGAM

Engineering geophysics Arc. SAR Hardware configuration KIGAM

Engineering geophysics VNA(Vector Network Analyzer) §Stepped KIGAM frequency §Both of Tx and Rx §Flexibility § 10 MHz – 20 GHz

Engineering geophysics Antenna H-Pol radiation pattern Frequency(GHz) 5. 0~5. 6 E-Plane(deg) 15(nominal) 12. 1~13 H-Plane(deg) 15(nominal) 15. 5~17. 5 Gain(d. Bi) 20(nominal) 20. 5 min. (20. 5~21. 8) VSWR 1. 5 max. 1. 4 max. Isolation 35 d. B 이하 50 d. B 이하 Weight(kg) 4 max. 3. 1 max. Beam Width Dual-Polarimetric Square Horn Antenna KIGAM

Engineering geophysics Amp and RF switch £Operating Freq. : 2~6 GHz £Power Gain: 34 d. B £ Maximum input: 6 d. Bm £Operation Freq. : ~20 GHz £GPIB interface £ 3중 1 X 2 SPDT KIGAM

Engineering geophysics Acquisition software Callibration Start Initialize all system Move to start position Acquisition Call cal: VV: Switching: Call cal: VH: Switching: Call cal: HV: Switching: Call cal: HH: Switching Save data Move or Stop KIGAM End