밀리미터파(Ka 밴드) 복합모드 탐색기용 고출력 펄스형 진행파관 증폭기(TWTA) 설계 및 제작

송성찬,김선기,이성욱,민성기 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.4

The traveling wave tube amplifier (TWTA), which can be applied to the Ka-band millimeter-wave multi-mode seeker, consists of an high voltage power supply(HVPS), a grid modulator, a command and control, and an RF assembly. We designed a power supply that generates a −17.9 kV high voltage by synchronizing the pulse repetition frequency(PRF) and power supply switching frequency(i.e. synchronization frequency), and a high-speed grid-switching modulator for RF pulse modulation. The TWTA, which is fabricated through miniaturization with a volume of 3.18 L, has high pulse switching characteristics of up to 18.5 ns. The maximum rise/fall time of the grid on/bias signal and peak power is more than 564.9 W. Moreover, an excellent spurious performance of −68.4 dBc or less was confirmed within the range of PRF and PRF/2.

무선 LAN용 이중 편파 2 X 2 배열 안테나

송성찬,이택경 한국전자파학회 2004 한국전자파학회논문지 Vol.15 No.7

In this paper, dual-polarized 2${\times}$2 array antenna is designed and fabricated for the polarization diversity applications in wireless LAN system. For the improved bandwidth and isolation characteristics, the aperture coupled feeding and the L-shaped probe feeding are employed for each polarization. The measured bandwidths of the fabricated antenna are 210MHz for aperture coupled feeding and 280MHz for L-shaped probe feeding. The isolation for two ports is -40dB and the antenna gain is measured as 14.3${\pm}$0.2dBi in the operating frequency band of wireless LAN. 본 논문에서는 무선 LAN 시스템에서 편파 다이버시티를 사용하기 위한 이중편파 특성을 가지는 2${\times}$2 배열 안테나를 설계, 제작하였다. 이중편파 안테나의 대역폭과 격리특성을 개선하고자 개구면 결합 급전 구조와 L형 이중 프루브 급전 구조를 사용하였다. 제작된 안테나의 -15dB 기준 반사손실 대역폭은 개구면 결합 급전에서 210MHz, L형 이중 프루브 급전에서 280MHz로 측정되었다. 두 입력포트간의 격리특성은 -40dB 이하이며, 안테나 이득은 무선 LAN 동작주파수 대역에서 14.3$\pm$0.2dBi로 측정되었다.

무선 LAN용 이중 편파 2×2 배열 안테나

송성찬,이택경 한국전자파학회 2004 한국전자파학회논문지 Vol.15 No.7

본 논문에서는 무선 LAN 시스템에서 편파 다이버시티를 사용하기 위한 이중편파 특성을 가지는 2 2 배열 안테나를 설계, 제작하였다. 이중편파 안테나의 대역폭과 격리특성을 개선하고자 개구면 결합 급전 구조와 L형 이중 프루브 급전 구조를 사용하였다. 제작된 안테나의 ­15 dB 기준 반사손실 대역폭은 개구면 결합 급전에서 210 MHz, L형 이중 프루브 급전에서 280 MHz로 측정되었다. 두 입력 포트간의 격리특성은 ­40 dB 이하이며, 안테나 이득은 무선 LAN 동작주파수 대역에서 14.3 0.2 dBi로 측정되었다.

낮은 정재파비와 삽입손실을 갖는 밀리미터파(Ka 밴드) 복합모드 탐색기용 2-축 도파관 로터리 조인트 설계 및 제작

송성찬,유성룡,임주현,정용인 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.2

In this study, a Ka-band waveguide rotary joint that can be applied to a millimeter-wave seeker is designed and fabricated. The proposed rotary joint maintains a low standing-wave ratio and low-loss characteristics, and has two rotary axes designed to enable azimuth and elevation rotation. The rotary joint is designed as a ridge-waveguide-type mode converter and a λ/4 choke structure to match the electromagnetic wave propagation mode between the spherical and circular waveguides. A performance test using a network analyzer and a high-power transmitter to assess vibration and shock were conducted. Results showed that the rotary joint had a very low standing-wave ratio of less than the maximum of 1.19:1 and an insertion loss of less than 0.80 dB at Fc±500 MHz.

밀리미터파 탐색기 시험 평가를 위한 HILS 및 시험 장비 개발

송성찬(Sung-Chan Song),나영진(Young-Jin Na),윤태환(Tae-Hwan Yoon) 한국전자파학회 2012 한국전자파학회논문지 Vol.23 No.1

본 논문에서는 고속의 단거리 탄도탄과 항공기 등의 표적을 탐지ㆍ추적할 수 있는 밀리미터파 탐색기의 종합성능 시험을 위해 개발한 HILS(Hardware-In-the-Loop Simulation)와 시험 장비를 설명한다. 이 시스템은 다양한 종류의 표적과 고속, 고기동 이동 표적의 궤적을 모사하기 위해 141개의 혼 안테나 배열, 배열 안테나 스위칭과 이득 및 위상 제어 알고리즘을 이용한다. 또한, 표적에 대한 속도, 거리뿐만 아니라, 클러터와 재밍 환경을 모사한다. 시스템 전체 구성과 표적 운동 모의기, 모의 신호 발생기, 고속 데이터 획득 장치, 통제 제어기 등과 같은 주요 구성품들의 구현과 측정 결과를 설명하였다. 이 통합 시스템은 동적 실시간 탐지/추적에 대한 밀리미터파 탐색기의 성능을 모의 비행 시나리오 기반으로 시험할 수 있다. This paper describes the developed HILS and test equipment in order to test the performances of MMW(Millimeter-Wave) seeker which can detect and track a high speed of short-range ballistic missile and aircraft. This system is used to 141 horn antenna array, array switching, and gain and phase control algorithm to simulate various kind of targets and trajectory of high speed and maneuver moving target. In addition, it simulates not only velocity and range for these targets but also clutter and jamming environments. System configuration and implementation and the measurement results of major subsystems such as target motion simulator, simulation signal generator, high speed data aquisition unit, and central control unit are presented. These systems could verify the detection and tracking performance of MMW seeker through dynamic real-time test based on simulation flight scenario.

밀리미터파 탐색기 내 누설신호 상쇄기 및적응형 알고리즘에 관한 연구

박지안,송성찬 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.1

A leakage canceller and adaptive algorithm for FMCW Radar is presented. Because a strong leakage signal causes various problems in the transceiver and digital processor, specific FMCW radars are in need of a leakage canceller. The leakage canceller has an adaptive structure and the algorithm calculates the prediction vector and learns the adaptive coefficient simultaneously. The proposed algorithm an improvement of 10 dB in the cancellation performance.

회전하는 안테나를 가진 레이다를 이용하여 비행체 종말 유도를 위한 직하 방향 레이다 영상형성

이혁중,송성찬,전주환 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.4

A linear frequency modulated pulse train waveform can be cost-effective in achieving high range resolution, and thus the synthetic aperture radar may be benefited by using the mixer output of the received signal. However, the image formation process from a mixer output is vulnerable to errors caused by stop-and-go approximation. In this paper, a nadir-looking imaging radar based on time domain correlation is proposed. Furthermore, to prevent the occurrence of ghosting effect in images, antenna placement on a rotating disk is proposed. Simulation results indicate that ghosting effect can be eliminated by employing the proposed antenna placement structure.

정확한 Closed-Form 그린함수를 이용한 코플래너 도파로 불연속 해석

강연덕,송성찬,이택경 한국항행학회 2003 韓國航行學會論文誌 Vol.7 No.2

실수축 상의 적분 방법에 의한 정확한 closed-form 그린함수를 이용하여 코플래너 도파로의 불연속에 대한 공간영역 full-wave 해석을 하였다. MPIE(Mixed Potential Integral Eqution)를 풀기 위한 수치계산 방법으로는 삼각형 요소를 이용한 갤러킨 방법을 사용하였다. 경계면에서 삼각형 요소상의 기저함수로는 선형함수를 사용하였으며, 관측점과 전원점이 일치하는 특이점 근방의 적분 계산을 위해 면적분을 선적분 형태로 바꾸어 피적분 함수의 특이점이 사라지도록 하는 해석적인 방법을 사용하였다. 실수축 적분방법에 의한 그린함수를 이용함으로써 불연속에 대한 정확한 특성을 구하였다. By using accurate closed-form Green's functions obtained from real-axis integration method, the full-wave analysis of CPW discontinuities are performed in space domain. In solving MPIE(Mixed Potetial Integral Equation), Galerkin's scheme is employed with the linear basis functions on the truangular elements in air-dielectric boundary. In the singular integral arising when the observation point and source point coincides, the surface integral is transformed into the line integral and the integral is evaluated by regular integration. By using the green's function from the real-axis integration method, the discontinuities are characterized accurately.

일차원과 이차원 Ka-대역 프린티드 다이폴 배열 안테나의 스캔 블라인드니스 분석

구한이,송성찬,남상욱 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.3

In this study, an active element pattern (AEP) of a printed dipole was analyzed in 1D and 2D arrays. First, an AEP of the printed dipole was obtained using the simulation in the 2D infinite array. The scan blindness in the 2D array occurred in the E-plane direction at around ±36°; however, it was barely observed in the 1D array. To analyze the cause of the scan blindness in the 2D array, the dispersion properties of a unit cell was obtained and compared with the scan blindness by frequency change. The difference between the scan blindness of the 1D and 2D arrays was clarified using the comparison of the Q value in the unit cell in the 1D and 2D arrays. Then, the coupling of the electric field in the E-plane direction was observed when nine elements were separated between the two ports in a linearly arranged dipole structure. Finally, the printed dipole array was fabricated, and an AEP was measured for the 11×1 and 11×3 sub arrays. The proposed theory was verified using these observations and by comparison with the simulation results.

FMCW MIMO 레이다를 이용한 거리-각도 동시 추정 기법

김정훈,송성찬,전주환 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.2

Frequency-modulated continuous wave(FMCW) radars with array antennas are widely used because of their light weight and relatively high resolution. A usual approach for the joint range and angle estimation of a target using an array FMCW radar is to create a range-angle matrix with the deramped received signal, and subsequently apply two-dimensional(2D) frequency estimation methods such as 2D fast Fourier transform on the range-angle matrix. However, such frequency estimation approaches cause bias errors since the frequencies in the range-angle matrix are not independent. Therefore, we propose a new maximum likelihood-based algorithm for joint range and angle estimation of targets using array FMCW radar, and demonstrate that the proposed algorithm achieves the Cramér-Rao bounds, both for range as well as angle estimation.