• Journal of Convergence for Information Technology
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• v.9 no.5
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• pp.125-129
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• 2019

This paper describes the jamming effect of phase-coded pulse compression(PCPC) radar. Barker code radar, a typical PCPC radar, separates transmission pulses into 13 or 31 small pulses and phase modulates and transmits each pulse signal to increase radar detection efficiency and reduce the influence of jamming. Generally, when the radar is subjected to jamming, the detection distance becomes shorter and the detection error rate becomes higher. In the case of noise jamming or carrier jamming on the PCPC radar, the jamming effect is very small for no phase-coded convergence. However, the jamming effect is large in the case of synchronous jamming using the pulse-coded signal as a jamming signal with DRFM. It can be seen that the jamming effect increases when the storage time of the pulse-coded signal is prolonged. This study is considered to be useful for PCPC radar and EW jamming system design.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.9
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• pp.889-895
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• 2011

In recent days, some techniques to prevent from radar detection have been applied on aircraft system. RWR(Radar Warning Receiver) can be used for estimating the source location of the aircraft which emits radar pulse. Current existing method of localizing radar pulse emission source is using AOA(Angle Of Arrival) and most techniques are focused on finding exact AOA to find exact location. In this case, however, the exact AOA does not always result in finding exact source location while target aircraft is moving fast. In this paper, a localization method using the phase delay of the radar pulse's low frequency applies and so a scanning method for the interest area does in order to estimate exact source location by using phase delay.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.8
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• pp.104-108
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• 2006

There are range and azimuth direction resolution of synthetic aperture radar on the aircraft or satellite. Wide bandwidth chirp pulse generation technology is prerequisite for SAR image with fine resolution. There are two kinds of digital chirp pulse generation technology as arbitrary waveform generator(AWG) and direct digital synthesizer(DDS). In this paper, we design and implement a digital chirp pulse generator to generate 300MHz wide bandwidth linear FM chirp pulse for the fine resolution image with direct digital synthesizer. Implemented chirp pulse generator can be useful for the SAR sensors to make 50cm range resolution image.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.137-143
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• 2018

Generally, a radar signal is modulated and transmitted in order to avoid signal detection. In electronic warfare, the specification of a radar is recognized by analysing the received radar pulses. In this paper, we propose an algorithm to recognize the PRI (Pulse Repetition Interval) type of radar signals. This algorithm uses the autocorrelation technique applying different comparison ranges according to the PRI type. It applies a short comparison window to stable and staggered PRI, and a relatively large comparison range to jittered PRI. The experiment shows that the proposed algorithm can discriminate the PRI type of radar pulses correctly. For the more, it can find out the stagger level of staggered type of radar signals.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.117-117
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• 2013

레이저 레이더용 시력안전파장대 고출력 광펄스 생성을 위한 광원으로 MOPA 구도로 광섬유 레이저를 제작 하였다. MOPA 기반 펄스 광섬유 레이저는시력 안정 파장대인 1,550 nm 대역 파장을 갖고 펄스폭이 2 ns 이하이며 반복률이 30~240 kHz 가변 가능하다. 광섬유 증폭단에서 1단 증폭기는 저잡음용 코어 펌핑 방식의 증폭기로 구현하였으며, 2단 증폭기는 중출력 증폭기로 코어 펌핑구조에 후방향 펌핑 구도로 설계하였다. 3단 증폭기는 최종목표인 2ns 이하의 펄스 폭 및 25 kWp 이상의 첨두출력을 달성하기 위하여 클래딩 펌핑 방식의 고출력 광증폭기로 구현하였다.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.397-400
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• 2006

본 논문에서는 DSP를 이용하여 코히어런트 레이더에 사용될 수 있는 확장성이 용이한 디지털 펄스 압축기를 시간영역에서 설계하고 그 내용을 분석하였다. 수신 거리 셀 및 FIR 필터 탭(tap) 수에 따른 펄스압축 연산시간을 ADSP21060을 사용하여서 분석함으로써, 설계하고자하는 레이더 시스템 요구 파라미터 들이 정해지는 경우 펄스압축기 구성에 소요되는 DSP의 수행 기능과 소요 수를 쉽게 예측할 수 있도록 운용특성을 분석하였다.

• Journal of IKEEE
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• v.8 no.1 s.14
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• pp.39-46
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• 2004

This paper presents the realization schemes for a multipurpose coherent mono-pulse radar Simulator with extendable features. We developed and installed the TSG(Timing Signal Generator) board which can simulate a mechanically rotate signal of antenna, an operation timing signal of pulse radar and target signal, to operate the simulator without real target in the indoor environment. Also, with the insertion of the radar signal processor, it came to be easy to achieve the addition of radar function algorithms, to rebuild or extend the multi-DSP Architecture into the simulator. Throughout the simulation results, we verified that the designed coherent mono-pulse radar simulator can exactly display a moving target on the realistic monitor(RD 9800).

• Electronics and Telecommunications Trends
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• v.28 no.2
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• pp.77-85
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• 2013

본고에서는 의료용, 보안용, 정밀거리 측위 등 다양한 분야에 응용이 가능한 근거리 고해상도 레이더 칩 기술에 대하여 소개한다. 먼저 근거리 고해상도 레이더 칩의 대표적인 구조와 동작원리에 대하여 기술하고 상용제품, 최신 논문에서 발표된 레이더 칩에 대하여 소개하였다. 고해상도를 얻기 위한 짧은 펄스 폭(나노초, 십억분의 1초)을 가지는 펄스를 송신하고 목표물을 맞고 되돌아온 에코 펄스를 고해상도로 수신하여 복원된 펄스로부터 얻어지는 거리정보로부터 신호처리 과정을 거쳐 고도화된 응용 분야에 따른 부가적인 정보를 얻는다. 수신기는 상관(correlation)법에 의한 수신 방식과 샘플링(sampling)에 의한 수신 방식으로 크게 나눌 수 있다. 끝으로 한국전자통신연구원에서 개발 중인 CMOS(Complementary Metal Oxide Semiconductor) 기술을 이용한 근거리 레이더 칩의 목표 성능, 구조, 설계 및 측정 결과에 대하여 소개하였다.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.159-163
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• 2013

In this paper, we propose a new method to deinterleave multi-stage stagger PRI signals of pulse radars using the electronic intelligence systems. While former algorithms were based on hardware PRI tracker only using the first deviation of the TOA of radar signals, this paper uses the first and the second deviation of TOA of radar signals and uses the PRI histogram method to deinterleave multiple PRIs of pulse radars. This algorithm can be used for deinterleaving various PRI signals at electronic intelligence systems.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.6
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• pp.98-105
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• 2003

We propose a new technique of deinterleaving multiple radar pulse sequences by means of genetic algorithm for threat identification in electronic warfare(EW) system. The conventional approaches based on histogram or continuous wavelet transform are so deterministic that they are subject to failing in detection of individual signal characteristics under real EW signal environment that suffers frequent signal missing, noise, and counter-EW signal. The proposed algorithm utilizes the probabilistic optimization procedure of genetic algorithm. This method, a time-of-arrival(TOA) only strategy, constructs an initial chromosome set using the difference of TOA. To evaluate the fitness of each gene, the defined pulse phase is considered. Since it is rare to meet with a single radar at a moment in EW field of combat, multiple solutions are to be derived in the final stage. Therefore it is designed to terminate genetic process at the prematured generation followed by a chromosome grouping. Experimental results for simulated and real radar signals show the improved performance in estimating both the number of radar and the pulse repetition interval.