• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.2
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• pp.166-172
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• 2018

To develop and evaluate the real-time SAR(Synthetic Aperture Radar) motion measurement system, true antenna phase center(APC) positions during SAT(Synthetic Aperture Time) are needed. In this paper, CDGPS(Carrier phase Differential Global Positioning System) post processing method is proposed to get the true APC position for spotlight SAR image formation. The CDGPS position is smoothed to remove high frequency noise which exists inherently in the carrier phase measurement. This paper shows smoothed CDGPS data is enough to provide the true APC for high-quality SAR image formation through motion measurement result, phase error estimation and IRF(Impulse Response Function) analysis.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.460-463
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• 1993

In this paper, The laser transmitter module is designed as the subsystem of the high repetitive laser rangefinder. The module consists of high voltage power supply, high voltage control circuits, high voltage discharger, electro-optic Q-switch driver, and laser resonator. The high voltage power supply is composed of 2-phase flyback converter. And it has 220W power level and 78% conversion efficiency. From the Q-switch driver of the crossed porro resonator, the phase retardation voltage is switched from 600V to -1500V with 200ns falling time. The module can be operated up to 15Hz. And it generates the laser pulse which has 20ns width and 80mJ.

• The Magazine of the IEIE
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• v.20 no.10
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• pp.116-124
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• 1993

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.6
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• pp.610-618
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• 2021

In this paper, a photonic-based microwave system technology is described, and a traveling-wave electro-optic modulator is designed and manufactured as a key component. The fabricated modulator is composed of a metal diffusion waveguide for optical transmission and a planar waveguide electrode on lithium niobate substrate for microwave transmission. The electro-optic response bandwidth of I and Q channels in a fabricated dual parallel Mach-Zehnder modulator were measured for 27.67 and 28.11 GHz, respectively. Photonic four times up-converted X-band frequency and linear frequency modulated signal were confirmed using the fabricated electro-optic modulator by S-band input signal. The confirmed broadband signal can be applied to a microwave system for surveillance and high-resolution ISAR imaging.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.59-69
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• 2003

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.6
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• pp.502-508
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• 2013

Various combinations of cartridge and orifice were applied for ground ejection tests of a gliding bomb model equipped with a new guidance kit. Larger diameter of orifice made larger ejection force at each of bomb racks. Normal operations of the wing deploying mechanism and the devices inside of the bomb model were confirmed. Also high speed video data showed that pitch angle of the gliding bomb varied due to the ejection force.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.10
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• pp.770-779
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• 2014

In this study, a numerical estimation method for 3D underwater radiated noise pattern using hull vibration and total acoustic power of the vibrating structure in the far-field is proposed. The underwater radiated noise pattern is known to be predicted using the vibration signals and radiation efficiency of each surface patch. But it is very difficult to know radiation efficiency of each surface patch which is one of important factors to calculate the 3D underwater radiated noise pattern. Instead of using radiation efficiency of each patch, the underwater radiated noise level is modified with the total acoustic power of the vibrating structure. The suggested estimation method for underwater radiated noise pattern is discussed with numerical model.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.1250-1254
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• 1992

This paper describes the designed and fabricated thermal imaging system with the SPRITE(Signal PRocessing in The Element) detector, operating in the 3-12 micron band. This system consists of an afocal telescope, a scan unit containing the SPRITE detector, an electronic processor unit and a cooler. The optical scan system utilizing rotating polygon and oscillating mirror, is 2-dimensional serial/parallel scan type using five elements of the detector. And the electronic processor unit performs digital scan conversion to reform the parallel data stream into serial analog data compatable with conventional RS-170 video. The scan field of view is 40 ${\times}$ 26.7 and the MRTD(Minium Resolvable Temperature Difference) is 0.6 K at 7.5 cycles/mm. The acquired thermal image indicates that this system has a satisfactory performance.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.703-705
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• 1992

In this paper, we calculate the inductance and resistance of the electromagnetic launcher by means of the 3D FEM and the analytical method. And, the dynamic models of the electromagnetic launcher are presented to calculate it's performance. We compared the analysis results with the experimental results and conclude that the presented analysis methods are reasonable.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.9-12
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• 2011

본 논문에서는 지대공 교전모의를 위한 대공포 모델을 설계하였다. 교전모의를 위한 대공포 모델은 조준점을 획득하기 위해 비행표적의 현재 상태에 대해서 표적 비행경로를 예측해야 한다. 비행표적으로 발포하는 포탄의 조준 정보을 계산하기 위해 비행표적에 대한 조준점 예측 기법을 소개하였다. 비행표적의 살상확률을 Calton Function을 이용하여 계산하였다. 표적의 속도, 위치 변화에 따른 대공 살상영역을 분석하였다. 본 연구에서 설계한 대공포의 분석결과를 MSA 프로그램의 결과와 비교하였다.