고속 전송선로의 신호왜곡과 신호 보전에 관한 연구

장연길,이영철,Jang, Yeon-Gil,Rhee, Young-Chul 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.2

본 논문은 외부 영향에 의하여 고속 정보시스템의 모듈사이에서 발생되는 전송잡음과 왜곡신호에 대한 신호 보전의 방법에 대하여 제안하였다. 고속 전송선로의 왜곡효과를 제거하기 위하여 전송선로 임피던스 정합에 의한 신호보전(signal integrity)은 고속 동작에 따른 전송선로효과 발생조건을 ADS로 모델링한 후 최적의 임피던스 정합을 단선 및 차동인터페이스 방식으로 구분하였다. 실험한 결과, 고속 정보통신시스템에 따르는 신호지연을 고려하여 최적의 단자 임피던스 값을 정합시켜 고속 신호의 최적 보전이 가능함을 보여 주었다. In this paper, we suggested the method of signal integrity for noises and distortion signal generated between high speed information transmission modules by external effects. Suggested method for signal integrity of impedance matching to remove transmission line distortion, We divided the impedance matching between the transmitter and the receiver module with the single line and differential line methods after confirmed the improvement of signal distortions through ADS simulation. the experimental results indicated that it is possible to keep signal integrity without signal distortions by matching the optimal termination impedance which are considering the signal delay of transmission line for using the high-performance modules.

과학기술문화의 확산방안에 관한 연구 : 충북지역을 중심으로 Focused on Chungbuk

장연길,신기호 청주대학교 사회과학연구소 2004 한국사회과학연구 Vol.26 No.2

본 연구는 지방정부의 과학기술 혁신체제 구축전략이라는 관점에서 충청북도의 과학기술의 현주소 및 기술수준을 진단하고 현재 추진 중에 있는 과학기술정책에 대한 문제점 분석 및 정책수요를 조사한 후, 이를 토대로 과학기술정책을 위한 발전방안을 제시하고자 한다. 또한 충북지역이 과학기술을 통하여 지역경제 활성화에 크게 기여할 수 있도록 지역의 과학기술수준 및 문제점을 분석하고 그에 따른 정책대안을 모색하는데 궁극적인 목적이 있다. Due to realizing the importance of local science and technology and the change in the support policy in that local government plays the leading role and central government supports the budget, it is urgent that a local government plans local science and technology policies to meet the change, In this paper the current and historical problems and practices of Chungbuk science and technology policies will be analysed and a development plan of Chungbuk science and technology culture will be explored. To be more specific, science and technology spreading programs of Chungbuk will be focused on. Both literature review and empirical research were used. In the theoretical research part, academic papers on local science and technology policies and science and technology culture were examined and for empirical research a survey was conducted. In chapter 1, the purpose, scope and method of research were explained. In chapter 2, theoretical review on local science and technology policies and science and technology culture was done. In chapter 3, a survey of local residents' concept on Chungbuk science and technology culture was examined. In chapters 4 and 5, development plans of Chungbuk science and technology culture were explored and concluded. To examined the concept of Chungbuk local residents on science culture, a survey with 24 questions on 4 areas of science culture environment, popularization of science culture and science culture spreading plans was conducted from August 2, 2004 to August 11, 2004, for 10 days. The subjects were government officials dealing with science and technology matters in Chungbuk province office and researchers working in industry-academy cooperation units of 13 universities in Chungbuk including Chungbuk University. The foundings of the research were that Chungbuk science and technology policies influence local economy activation greatly and to carry out science and technology policies efficiently the spread of science culture is very important. To spread science and technology the following measures are needed. First, more science culture spaces need to be established like science parks and science museums for scientification of local lives. Second, various science technology events need to be organized like robot contests, industrial technology exhibitions, science plays and experience programs. Third, infrastructure for the spread of science technology culture needs to be expanded like establishing a science technology exclusive organization, increase of science technology budget and legislation of relevant ordinances. Fourth, science technology manpower needs to be expanded including children, youths, university students and local residents. Lastly, to encourage easy participation of all provincial residents various programs need to be organized like street science events, family oriented science events, street exhibitions and science play performances.

WLAN/WiMAX 삼중대역에서 동작하는 모노폴 안테나의 설계

윤중한,장연길,이영철 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.3

In this study, a novel dual‐band planar monopole antenna for wireless local area network (WLAN)/ Worldwide Interoperability of Microwave Access (WiMAX) application was designed, fabricated, and measured. The proposed antenna consists of two hookshaped strips, an asymmetric ground plane, and a rectangular slit in the ground plane. Acceptable agreements between the measured and simulated results are achieved. Numerical and experimental results demonstrate that the proposed antenna satisfies the 10 dB impedance bandwidth requirement while covering the WLAN and WiMAX bands simultaneously. This paper also presents and discusses the 2D radiation patterns and 3D gains according to the results of the experiment that was conducted.

Dynamic Range를 고려한 K-band Front-End Module 설계

한건희,장연길,이영철,Han, Geon-Hee,Jang, Youn-Gil,Rhee, Young-Chul 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.1

In this paper, we designed and analysed K-band front-end module for digital microwave communication system receiver which improvement of dynamic range. We also suggested method of minimum amplified input signal level used to minimize noise figure of low-noise amplifier for High dynamic range. The designed modules consist of active mixer with conversions gain and PL-DRO with high stability and quality factor. The designed modules performance is that has the characteristics of over 54dB conversion gain, 1.3dB noise figure. 본 논문에서는 디지털 마이크로파 통신 시스템 수신기의 동작범위(Dynamic Range) 향상을 위한 설계 방법을 K-band FEM(Front-End Module)에 적용하여 설계 및 분석하였다. 동작범위를 광범위하게 설계하기 위해 저 잡음 증폭기(LNA)의 잡음지수를 최소화하여 증폭된 입력신호 레벨을 최소화하는 방법을 제안하였으며, 주파수 변환은 높은 선택도(Q)와 안정도가 높은 위상고정 유전체 발진기(PL-DRO) 및 변환이득을 가지는 능동믹서로 구성하였다. 각각의 모듈을 집적화하여 측정한 결과 약 54dB의 변환이득(CG)과 1.3dB의 전제 잡음지수(NF)를 나타내었다.

선박 레이다용 60W X-band Cascade SSPA 구현

김민수,장연길,이영철,Kim, Min-Soo,Jang, Yeon-Gil,Rhee, Young-Chul 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.7 No.1

본 논문에서는 펄스압축 된 X-대역 마이크로파 신호를 60와트의 출력전력과 30%이상의 전력부가효율(PAE)으로 증폭시키는 반도체증폭기(SSPA)를 구현에 대하여 논의하였다. 구현된 60W의 SSPA는 케스케이드 결합 증폭기로 설계하였고 케스케이드(cascade) 결합 증폭기는 내부정합된 GaAs FET를 3단으로 구동증폭기를 설계하였으며 주 전력증폭단은 내부정합된 GaN HEMT(High Electron Mobility Transistor)로 설계하였다. 구현된 SSPA는 주파수 범위 $9.41{\pm}0.03GHz$, 펄스 주기 1ms, 펄스폭 100us, 듀티사이클 10% 조건에서 전체 이득 37dB 이상, 48dBm(60W)의 출력전력의 성능을 나타내었어 구현된 SSPA는 펄스압축기술을 이용한 디지털 선박용 레이다에 적용할 수 있다. In this paper, An X-band solid state power amplifier(SSPA) for pulse compressed microwave signal with 60Watt power and power added efficiency(PAE) above 30% is described. Designed 60Watt high power amplifier(HPA) was implemented by cascade coupled amplifiers, and it is consisted on three stage drive amplifiers with internally matched GaAs FET and one stage main power amplifier with an internally matched GaN HEMT. The designed SSPA has performance with more than total power gain 37dB and output power 48dBm(60-W) in condition of frequency range $9.41{\pm}0.03GHz$, pulse period width under 1ms and duty cycle under 10%. The implemented SSPA can apply to high quality digital marine radar applications with pulse compression technique.

WLAN/WiMAX 삼중대역에서 동작하는 모노폴 안테나의 설계

윤중한(Joong-Han Yoon),장연길(Kil-Yeon Jang),이영철(Young-Chul Rhee) 한국전자통신학회 2012 한국전자통신학회 논문지 Vol.8 No.3

본 논문은 WLAN/WiMAX 시스템에 적용 가능한 이중대역 평면형 모노폴 안테나를 설계, 제작 및 측정하였다. 제안된 안테나는 2개의 훅크 모양의 선로, 비대칭 접지면 그리고 접지면에 사각 슬릿을 갖도록 설계하였다. 측정과 시뮬레이션 결과사이의 데이터가 잘 일치하고 있는 데이터를 얻었으며 -10dB 임피던스 대역폭을 기준으로 WLAN과 WiMAX 대역을 동시에 만족하고 있음을 확인하였다. 또한 2D 그리고 3D 방사패턴과 이득에 측정결과가 제시되고 논의되었다. In this study, a novel dual‐band planar monopole antenna for wireless local area network (WLAN)/ Worldwide Interoperability of Microwave Access (WiMAX) application was designed, fabricated, and measured. The proposed antenna consists of two hookshaped strips, an asymmetric ground plane, and a rectangular slit in the ground plane. Acceptable agreements between the measured and simulated results are achieved. Numerical and experimental results demonstrate that the proposed antenna satisfies the 10 dB impedance bandwidth requirement while covering the WLAN and WiMAX bands simultaneously. This paper also presents and discusses the 2D radiation patterns and 3D gains according to the results of the experiment that was conducted.

X-band 위성통신용 저잡음 증폭 모듈 설계

한건희(Han Geon Hee),김민수(Kim Min Su),이상진(Lee Sang Jin),장연길(Jang Youn Gil),이영철(Rhee Young Chul) 한국통신학회 2011 한국통신학회 학술대회논문집 Vol.2011 No.6

Dynamic Range를고려한 Ka-band 능동 혼합기설계

황희근(Hee-Geun Hwang),한건희(Gun-Hee Han),장연길(Yeon-Gil Jang),구융서(Ryung-Seo Koo),이영철(Young-Chul Rhee) 한국통신학회 2012 한국통신학회 학술대회논문집 Vol.2012 No.6