A5003435302- Antenna Design and Optimization
- Advanced SAR Imaging Techniques
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Antenna Design and Analysis
- Microwave Engineering and Waveguides
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Advanced Antenna and Metasurface Technologies
- Nuclear physics research studies
- Microwave and Dielectric Measurement Techniques
- Quantum Information and Cryptography
- Electromagnetic Compatibility and Measurements
- RFID technology advancements
- Particle Accelerators and Free-Electron Lasers
- Embedded Systems and FPGA Design
- Superconducting Materials and Applications
- Quantum Computing Algorithms and Architecture
- Spacecraft Design and Technology
- Quantum-Dot Cellular Automata
- Soil Moisture and Remote Sensing
- Geoscience and Mining Technology
- Soft Robotics and Applications
- Structural Analysis and Optimization
- Power Systems and Technologies
- Radio Astronomy Observations and Technology
Agency for Defense Development
2013-2024
Korea Advanced Institute of Science and Technology
2015-2018
Daejeon Institute of Science and Technology
2018
Korea Aerospace University
2013-2016
Ningbo Science and Technology Bureau
2007
University of Mississippi
2001-2006
Fermi National Accelerator Laboratory
2006
Pohang University of Science and Technology
2005
Tsinghua University
1999
From a sample of 1172 +/- 61 D(+)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)-->pi(-)pi(+)pi(+))/gamma(D(+)-->K-pi(+)pi(+)) = 0.0311 0.0018(+0.0016)(-0.0026). Using coherent amplitude analysis to fit the Dalitz plot these strong evidence that scalar resonance mass 478(+24)(-23) 17 MeV/c(2) and width 324(+42)(-40) 21 accounts for approximately half all decays.
From a sample of 848+/-44 D(+)(s)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)(s)-->pi(-)pi(+)pi(+))/gamma(D(+)(s)-->straight phipi(+)) = 0.245+/-0.028(+0.019)(-0.012). Using Dalitz plot analysis this three body decay, significant contributions from the channels rho(0)(770)pi(+), rho(0)(1450)pi(+), f(0)(980)pi(+), f(2)(1270)pi(+), and f(0)(1370)pi(+). We also present values obtained for masses widths resonances f(0)(980) f(0)(1370).
A model-independent partial-wave analysis of the S-wave component Kπ system from decays D+ mesons to three-body K−π+π+ final state is described. Data come Fermilab E791 experiment. Amplitude measurements are made independently for ranges K−π+ invariant mass, and results obtained below 825 MeV/c2, where previous exist only in two mass bins. This method parametrizing a decay amplitude represents new approach analyzing such decays. Though no model required S-wave, parametrization relatively...
Infinitesimal dipole modeling (IDM) can model antennas analytically with small amounts of data. Constrained IDM has been proposed to improve the efficiency by fixing positions and orientations elements. The restrictions have a tradeoff requiring more Therefore, technique disadvantage having low practicality. A recursive convex optimization based on reweighted l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> -norm is for sparse IDM. By...
For accurate beam analysis of a radiating antenna array on complex platform, the mutual coupling and platform scattering effects are important. We proposed pattern method for an which combines active element receiving mode hybrid geometrical theory diffraction current Green's function technique. This clearly mathematically divides into components. 12 linear dipole embedded in aircraft, analyses boresight error using were verified with moment results, simulated FEKO. With reasonably good...
A model-independent partial-wave analysis of the S-wave component Kπ system from decays D + mesons to three-body K -π π final state is described.Data come Fermilab E791 experiment.Amplitude measurements are made independently for ranges invariant mass, and results obtained below 825 MeV/c 2 , where previous exist only in two mass bins.This method parametrizing a decay amplitude represents new approach analysing such decays.Though no model required S-wave, parametrization relatively...
Large spaceborne antennas should be lightweight, a factor related to the development costs of launch vehicles. In order overcome this drawback, feasibility study new carbon fiber reinforced polymer (CFRP) named M55J/RS3 is carried out for synthetic aperture radar (SAR) reflector antenna. particular, high resolution detected images taken into consideration. To validate electrical performance, test CFRP specimen fabricated, and transmission/reflection coefficients are measured using standard...
Solid surface deployable antenna provides reduced volume in the stowage and relatively high precision. CFRP(Carbon Fiber Reinforced Polymers) is a composite material that has properties of light weight modulus. The electric characteristic layered laminate CFRP investigated. For incomplete deployment panels, degradation characteristics are analyzed.
A procedure for antenna parameter selections is proposed that considers the relationships between synthetic aperture radar performance and parameters of a parabola-type reflector with central flat dish. The effects dish designed weight reduction on beam pattern are also quantitatively analyzed using commercially available software based physical optics algorithm. results theoretical analysis simulation predict larger size in an increase sidelobe level, which reason two important ambiguities,...
In this letter, we present a method to design an elevation beam pattern mask for spaceborne synthetic aperture radar (SAR) reduce the range ambiguity. The proposed two-way mask, which requires relatively low sidelobe levels only in direction of strong ambiguous echoes, can be highly suitable enhancing ambiguity signal ratio (RASR). power different echoes are estimated based on backscattering coefficient model and satellite geometry. To meet both transmit receive patterns synthesized...
Measurement-device-independent quantum key distribution (MDI-QKD) is immune to all the detection attacks, thus when it combined with decoy state method, final unconditionally safe. In this paper, we propose perform MDI-QKD odd coherent (OCS) and compare results weak source scenario. Our simulation indicates that both secure rate transmission distance can be improved evidently OCS owing lower probability of multi-photon events OCS. Furthermore, apply finite analysis obtain a practical rate.
The original measurement of device-independent(MDI)quantum key distribution(QKD) is reviewed, and a modified protocol using rotation-invariant photonic state proposed. Initial encoding final decoding information in our MDI-QKD implementation can be conveniently performed the polarization space, while transmission done hybrid space. Our analysis indicates that both secure rate distance improved by owing to its lower error rate. Furthermore, polarization-OAM qubits approach only needs insert...
Abstract In this paper, we propose a closed‐form equation and novel design procedure for suppressing the space harmonics coupling loss of radiated‐mode leaky coaxial cable (LCX). The LCX with periodic principal slots is analyzed using Floquet theory, its radiation usually contains higher that may cause an uneven loss. A derived to determine orders being suppressed. Consideration resonant points makes it possible choose operating‐frequency range antenna from passband region, where level low....
We present the measurement system for electrical characteristics of inhomogeneous and anisotropic carbon fiber reinforced polymer(CFRP) material by employing waveguide 2-port measuring method. The effective permittivity conductivity CFRP have been estimated according to direction radar application in frequency range from 8GHz 12GHz.
본 논문에서는 주파수 체배 방식을 이용하여 고해상도 영상 레이더의 광대역 파형 생성을 위한 효율적인 기법에 대한 연구를 수행하였다. 또한 직교 변조기와 체배기를 사용한 첩 변조 파형의 대역폭 확장시 발생되는 3차 혼변조 성분에 의한 스펙트럴 재성장에 근본적인 원인을 분석하였다. 변조기의 진폭 및 위상 불균형 오차에 요구 조건을 시뮬레이션을 통하여 정의하였다. 이와 같은 해석을 임펄스 응답 특성인 거리 방향 해상도, PSLR(Peak Sidelobe Ratio) ISLR(Integrated 특성이 악화되는 것을 최소화시킬 수 있었다. 체배기와 메모리 맵 발생장치가 제작되었으며, 진폭과 오차를 최소화시킴으로써 생성된 SAR 부엽에서 재성장 성분을 최소화 시키는 보상 기법이 제시되었다. I Q 채널간의 특성을 조절함으로써, 반송파 레벨을 －28.7 dBm에서 －53.4 dBm으로 억압할 있었으며, S-대역에서 150 MHz 대역폭의 파형을 X-대역에서 600 대역폭으로 성공적으로...
Artificial Bee Colony (ABC) algorithm is a heuristic optimization inspired by the process that honey bee swarm find best food source. The ABC can efficiently global solution on each various problem compared with previous algorithms such as genetic (GA) and particle (PSO). In this paper, amplitude phase of 40-element 1-D uniform linear array are simultaneously optimized using algorithm. Furthermore, space algorithm, representing amplitudes phases, discretized 6-bit control for application to...
본 논문에서는 광역 관측을 위하여 새롭게 제안되고 있는 TOPS SAR 운용기법에 대한 모드 설계 및 성능 분석을 수행하였다. 모드는 기존 ScanSAR 모드의 단점인 scalloping을 개선하기 제안된 모드로서, 진행방향으로 안테나 빔을 조향하면서 영상 데이터를 획득하는 새로운 획득 기술이다. 모드에 기술적 운용 개념을 소개하고, 변수를 추출하기 위한 결과를 제시한다. 또한 설계된 이용하여 주요 성능인 IRF, NESZ, DTAR을 분석하여 In this paper, the design technique of wide swath TOPS(Terrain Observation by Progressive Scan) imaging mode is introduced. The overcomes scalloping limitations imposed steering antenna pattern along track direction during acquisition a burst....
본 논문에서는 기 개발된 능동형 SAR(Synthetic Aperture Radar) 안테나의 송수신 모듈 출력에서 발생하는 이득과 위상 오차를 보정하는 방법에 대해 소개한다. 먼저 오차에 정의하고, 시범 측정을 통해 획득한 측정값을 바탕으로 오차의 특성을 분석한 뒤, 이를 보상하기 위한 모듈의 제어 방법을 제안하였다. 16조의 모듈로 구성된 안테나에서 보정 전 이득은 28.2~29.0 dBm, 위상은 <TEX>$101.7^{\circ}{\sim}165.2^{\circ}$</TEX>의 분포를 보였으나, 보정후 27.4~28.0 <TEX>$116.1^{\circ}{\sim}120.0^{\circ}$</TEX>의 나타내었다. 이러한 출력 배열 이론을 적용하여 안테나 빔 패턴을 생성하고 비교함으로써 제안한 방법이 SAR 시스템의 성능 만족에 효과적임을 검증하였다. In this paper, a compensation method of the amplitude and phase...
In this letter, we propose a method to improve antenna model accuracy for active phased-array synthetic aperture radar (SAR) antennas. The is mathematical modeling represent real radiated patterns of the SAR antenna. Unidentified systematic error contributions degrade model. Unlike previous approaches that only perform on-ground validation or in-orbit extraction beam pattern, proposed can be utilized using optimization matrix based on convex algorithm. validated by measured results...
Because most realistic synthetic aperture radar (SAR) antennas use quantized controllers, beamforming is an important technique. However, existing heuristic algorithms have some drawbacks to the problem. The spend a lot of computation time and we should get appropriate mask pattern empirically. Therefore, hybridized deterministic algorithm called convex optimization with artificial bee colony (ABC) which overcome drawbacks. Using suggested convex-ABC hybrid algorithm, conducted for range...