• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.92-116
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• 1999

Tomographic approaches to image underground structure using electrical properties, can be divided into DC resistivity, electromagnetic, and radar tomography, based on the operating frequency. DC resistivity and radar tomography methods have been recently applied to site investigation for engineering purpose in Korea. This paper review these two tomography methods, through the case histories acquired in Korea. As another method of borehole radar survey, borehole radar reflection method is included, and its inherent problem and solution are discussed, how to find the azimuth angle of reflector using direction-finding-antenna. Since the velocity anisotropy of radar wave has been commonly encountered in field data, anisotropic radar tomography is discussed in this paper. In DC resistivity tomography, two subjects are focussed, electrode arrays, and borehole effect owing to the conductive fluid in borehole. Using the numerical modeling data, various kinds of electrode ways are compared, and borehole effect is illustrated. Most of the case histories presented in this paper are compared with known geology, core logging data, and/or Televiewer images.

• Defense and Technology
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• no.4 s.230
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• pp.38-47
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• 1998

레이다는 저고도 표적에 대한 탐지능력 ECCM 능력, 대방사유도탄에 대한 대처능력이 우수해야 하며, 동시다발 표적에 대한 탐지와 추적능력을 보유해야 하고 다기능 및 다목적 용도를 위해서 또는 시시각각으로 변하는 상황에 대처하기 위해서는 시스템의 융통성과 잠재능력이 커야 한다.

• Defense and Technology
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• no.3 s.229
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• pp.30-41
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• 1998

'항공기와 레이다'는 '창과 방패'와 같은 관계처럼 어떤 때는 서로 상대하는 어떤 때는 상호 협동하는 모습으로 늘 같이 존재한다. 기습공격이 동서고금을 망라한 전쟁의 기본양상이라면 현대전에서 공중공격은 가장 빠르고 효과적인 기습작적이었고 앞으로도 그 양상은 계속 변하지 않을 전망이다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.4
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• pp.308-315
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• 2018

In this paper, we present the basic design results for high-resolution radar development at S-band frequency that can precisely measure the miss distance between two targets. The basic system requirement is proposed for the design of a 3.5 GHz linear frequency-modulated (LFM) radar with maximum detection distance and distance resolution of 2 km and 1 m, respectively, and the specifications of each module are determined using the radar equation. Our calculations revealed a signal-to-noise ratio ${\geq}30dB$ with a bandwidth of 150 MHz, transmission power of 43 dBm for the power amplifier, gain of 26 dBi for the antenna, noise figure of 8 dB, and radar cross-section of $1m^2$ at a target distance of 2 km from the radar. Based on the calculation results and the theory and method of LFM radar design, the hardware was designed using software defined radar technology. The results of the subsequent field test are presented that prove that the designed radar system satisfies the requirements.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.7
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• pp.1147-1156
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• 2001

In this paper, a new design architecture of radar signal processor in real time is proposed. It has been designed and implemented under the consideration to minimize the inter-processor communication overhead and to maintain the coherence in Doppler pulse domain and in range domain. Its structure can be easily reconfigured and reprogrammed in accordance with an addition of function algorithm or a modification of operational scenario. As we designed a task configuration for parallel processing from measures of computation time for function algorithms and transmission time for results by signal processing, data exchange between processors for performing of function algorithms could be fully removed. Morocco-2 board equipped ADSP-21060 processor of Analog Devices inc. and APEX-3.2 developed for SHARC DSP were used to construct the radar signal processor.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.8
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• pp.619-627
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• 2017

MIMO(Multi-Input Multi-Output) radar is an emerging radar technology for its numerous advantages. However, in the electric warfare viewpoint, MIMO radar is a new developed radar technology for that existing parameter estimation cannot applied and a new radar parameter estimation based on the characteristics of MIMO radar is desired. In this paper, we propose a blind estimation scheme for the number of orthogonal waveforms of a uniform linear array(ULA) MIMO radar using minimum two electronic sensors.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.2
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• pp.129-138
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• 2017

This paper has been shown for the extraction of Doppler signature from the radar signal for an air-breathing targets tracked in the ground radar. For the extractions, a Doppler resolution is confirmed from mathematical modeling of PT(pulse train) waveform. Doppler signatures of air-breathing target are varied to radar aspect angle of engine and are determined from physical parameter of jet engine. To confirm such Doppler signatures, the radar signal reflected from the air-breathing target is obtained by our radar signal storage. After this extraction, radar aspect angle of engine has estimated from tracking information. Relative differences of Doppler signatures to radar aspect angle of engine is verified from these results and Doppler profiles for radar target identification appliance are presented.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.1
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• pp.70-78
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• 2019

In this paper, modeling of a high-resolution multi-function radar is proposed to simulate radar performance in a war game simulator, called AddSIM. To incorporate the multi-function radar model into the AddSIM, the modeling must comprise a component-based structure consisting of physics, logics, and information blocks. Therefore, we assign the RF hardware of a RADAR as the physic block, a controller as the logics block, and the RF specifications of the RADAR as the information block. Detailed modeling of the physics and logics blocks are addressed, and data structure is also presented on an engineering level. On a multi-target engaged scenario, the performance of the multi-function radar is numerically analyzed and its validation is examined.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1055-1060
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• 2020

This study is a study on the analysis and measurement of the radar cross-sectional area of a miniature aircraft. Radar cross-sectional area for miniature aircraft in advance were analyzed using an electromagnetic analysis tool, and an actual miniature aircraft was manufactured and measured in an anechoic chamber. When measuring, the old model was used as reference data for RCS(radar cross section) characteristics and applied to the test result data of the actual reduced model. The measurement method improved the accuracy of the measurement by applying time gating to remove the influence on the components scattered inside the anechoic chamber. The RCS test results of the reduced model showed relatively high RCS characteristics in the microwave band, as the previous analysis results. In the future, we plan to utilize the method of RCS analysis and measurement for the target of the radar in the VHF(Very High Frequency)/UHF(Ultra High Frequency) band with a relatively large wavelength.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.9
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• pp.756-759
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• 2017

In this paper, the radar cross section of a tank is analyzed at millimeter wave W-band. We calculate the radar cross section of the tank using the program based on PO and PTD and the computed results are compared with those of commercial simulator to check the accuracy of computations. The radar cross section is calculated in terms of the incident angle, polarization, and tank with or without cannon. The radar cross section can be reduced by changing the shape of the turret that can be applied to stealth tanks.