SPD를 이용한 2.4 GHz PLL의 위상잡음 분석

채명호,김지흥,박범준,이규송,Chae, Myeoung-ho,Kim, Jee-heung,Park, Beom-jun,Lee, Kyu-song 한국군사과학기술학회 2016 한국군사과학기술학회지 Vol.19 No.3

In this paper, phase noise analysis result for 2.4 GHz PLL(phase locked loop) using SPD(sample phase detector) is proposed. It can be used for high performance frequency synthesizer's LO(local oscillator) to extend output frequency range or for LO of offset PLL to reduce a division rate or for clock signal of DDS(direct digital synthesizer). Before manufacturing, theoretical estimation of PLL's phase noise performance should be performed. In order to calculate phase noise of PLL using SPD, Leeson model is used for modeling phase noise of VCO(voltage controlled oscillator) and OCXO(ovened crystal oscillator). After theoretically analyzing phase noise of PLL, optimized loop filter bandwidth was determined. And then, phase noise of designed loop filter was calculated to find suitable OP-Amp. Also, the calculated result of phase noise was compared with the measured one. The measured phase noise of PLL was -130 dBc/Hz @ 10 kHz.

숨어 피는 꽃

채명호 고요아침 2014 시조시학 Vol.51 No.-

위상비교 방식을 이용한 2차원 방향탐지 정확도 분석

채명호(Myoung-Ho Chae) 한국전자파학회 2017 한국전자파학회논문지 Vol.28 No.8

본 논문에서는 신호의 고각과 방위각을 추정하기 위한 위상비교 방식의 방향탐지 정확도에 대해 분석하였다. 안테나 4개를 균일 배치한 구조와 3개를 균일 배치한 구조의 고각과 방위각 추정에 대한 분석적 표현을 제시하였고, 방향탐지 오차를 분석하였다. 또한 정확도, 형상, 채널수 관점에서 두 구조를 비교하여 방향탐지 장치 설계에 대한 방향을 제시하였다. 방향탐지 분석결과는 시뮬레이션 결과와 유사한 분포를 나타내고, 1.2 °RMS 이내의 차이를 갖는 것을 확인하였다. 분석 결과로부터 SNR 20 dB, 베이스라인 길이가 반파장일 때, 안테나 4개를 균일 배치한 구조의 경우, 안테나 3개를 배치한 구조에 비해 고각 방향탐지 정확도는 1.15 배 높으며, 방위각 방향탐지 정확도는 서로 동일함을 확인하였다. 또한 2차원 방향탐지 구조는 1차원 방향탐지 구조에서 발생하는 코닝에러가 제거되는 것을 확인하였다. In this paper, the author analyzes direction finding accuracy based on phase comparisons to estimate elevation and azimuth angles of arrival signals. This paper considers the uniform array configurations using four and three elements. In that direction finding structures, I present the analytic expressions for estimated elevation and azimuth angles and then analyze the direction finding errors. And one presents the design guideline of direction finding system in comparison with aspects of accuracy, structure, the number of channels in that structures. The analysis result is similar with simulation one and has difference within 1.2 °RMS. From the proposed analysis results, one knows that when SNR is 20 dB and the baseline is half of wavelength, the estimated elevation accuracy of the uniform array using four elements is 1.15 times better than the one of the uniform array using three elements and the estimated azimuth accuracy is same each other. In addition, one knows coning error is eliminated in 2-D direction finding structure.

YTO를 이용한 광대역 저 위상 잡음 주파수 합성기 설계 및 제작

채명호(Myeong-Ho Chae),이행수(Hyeang-Soo Lee),홍성용(Sung-Yong Hong) 한국전자파학회 2013 한국전자파학회논문지 Vol.24 No.11

광대역에서 저 위상 잡음 특성을 갖는 주파수 합성기를 YTO를 이용하여 설계하였다. 위상 잡음을 낮추기 위해 분주비를 줄일 수 있는 offset PLL 구조를 사용하였다. 위상 잡음 모델링을 이용하여 PLL의 loop filter, YTO의 Main 드라이버 회로와 FM 드라이버 회로의 loop filter를 최적화하였다. 또한, 1 ㎐ 이하의 고해상도를 얻기 위하여 DDS를 기준 신호로 사용하였다. 제작된 주파수 합성기의 위상 잡음은 3.2~6.8 ㎓에서 ?107 ㏈c/㎐ 10 ㎑ 이하로 측정되었다. 측정 결과와 위상 잡음 모델링을 통해 계산한 값과 비교한 결과, 잘 일치함을 확인 함으로써 위상 잡음 모델링이 타당함을 검증하였다. The low phase noise and wideband frequency synthesizer has been designed by using YTO. Offset PLL structure is used for reducing a division ratio of feedback loop. The phase noise modeling is applied to optimize loop filter of PLL and YTO module. And DDS is used as reference signal of frequency synthesizer for fine resolution. The fabricated wideband frequency synthesizer has the output frequency of 3.2 ㎓ to 6.8 ㎓, phase noise of ?107 ㏈c/㎐ at 10 ㎑ offset from the carrier and frequency resolution of 1 ㎐. The measured phase noise is well agreed with the simulated one.

광대역 주파수 합성기용 YTO 모듈 설계 및 제작

채명호(Myeong-Ho Chae),홍성용(Sung-Yong Hong) 한국전자파학회 2012 한국전자파학회논문지 Vol.23 No.11

3.2~6.5 GHz 광대역 특성을 갖는 YTO(YIG Tuned Oscillator) 모듈을 설계 및 제작하였다. 위상 잡음 특성을 개선하기 위해 샘플링 믹서를 이용한 offset PLL(Phase Locked Loop) 구조로 설계하였다. 이 방식은 샘플링 믹서, 위상 비교기, 루프 필터, 전류 드라이버 회로, YTO로 구성된다. 측정 결과, 4.5 GHz에서 위상 잡음은 수식으로 도출한 값과 유사한 10 kHz offset 주파수에서 ?100 dBc/Hz를 얻었다. 제작된 YTO 모듈의 위상 잡음은 동작 주파수 대역에서 기존 PLL 구조에 비해 10 dB 이상 우수함을 확인하였다. The 3.2~6.5 GHz wideband YTO(YIG Tuned Oscillator) module is designed, fabricated and measured. To improve the phase noise characteristic of the YTO module, offset PLL(Phase Locked Loop) structure with sampling mixer is applied. This YTO module is composed of sampling mixer, phase detector, loop filter, current driver, and YTO. The phase noise of the fabricated YTO module is measured as ?100 dBc/Hz at 10 kHz offset frequency, which approximates the predicted result at the center frequency of 4.5 GHz. This YTO module presents over 10 dB improved phase noise compared to conventional PLL module from operating frequency.

Design and Fabrication of a Compact 2D Phase Comparison Direction Finder

전종화,채명호 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.3

In this study, a compact, low-power 2D phase comparison direction finder was designed and fabricated. For the design of the directionfinding (DF) receiver, a 2D phase comparison DF equation was derived from the structure of four uniformly arranged antennas, and the main design parameters were derived from the receiver’s system parameters. Based on the derived DF equations and design parameters, a DF receiver was designed, and a direction finder was fabricated. A comparison of the fabricated direction finder to a simulation model showed that its performance was comparable to the simulated performance and satisfied the system parameters. Moreover, a comparison of the theoretical, simulated, and actual injection and radiation DF precision showed that the fabricated direction finder had performance consistent with that indicated by the theoretical and simulation results and DF precision within 0.5°.

L대역 신호 수집을 위한 소형 디지털 수신기 설계 및 제작

전종화,조성진,채명호 한국전자파학회 2019 한국전자파학회논문지 Vol.30 No.11

In this paper, we have designed and fabricated a compact digital receiver for acquiring L-band signals. A receiver, based on direct RF sampling, has been designed for a compact multi-channel receiver. The design of the receiver is based on the system parameters and it is further fabricated on the basis of the simulation model. The performance of the fabricated digital receiver is analyzed by comparing it with the performance of the simulation model. It is observed that the fabricated digital receiver exhibits a receive sensitivity of −102 dBm, and eventually reaches the dynamic range of 62.7 dB.

다중 프로토콜 분석을 위한 프로토콜 구조 및 시퀀스 탐색 방법

조현우,박지환,채명호,이해영,임완수 한국통신학회 2024 韓國通信學會論文誌 Vol.49 No.4

본 논문에서는 악성 코드 및 해킹 시스템 등의 사이버 공격을 방지하기 위한 프로토콜 역공학에서 다중 프로토콜 분석을 위한 프로토콜 구조 및 시퀀스 탐색 방법을 제안한다. 다중 프토토콜 데이터는 2개 이상의 정의되지않은 프로토콜로 이루어진 데이터로 프로토콜의 분류가 필요하다. 본 연구에서는 다중 프로토콜 분류를 위해 계층적 군집화 방법을 사용하고 프로토콜 구조 및 시퀀스 탐색 알고리즘의 성능 및 계산복잡도의 향상을 위해 프로토콜 메시지의 payload를 제거하는 과정을 수행한다. 프로토콜 구조 및 시퀀스 탐색 알고리즘으로 sliding window를사용한 빈번한 시퀀스 탐색 알고리즘과 CSP (Contiguous Sequential Pattern) 알고리즘을 사용하여 제안하는 방법에 대한 성능평가를 수행하였다. Sliding window를 사용한 빈번한 시퀀스 탐색 알고리즘과 CSP 알고리즘 모두에서 계층적 군집화와 payload를 제거하는 과정을 모두 수행하면 향상된 결과를 얻을 수 있었다. This paper introduces a protocol structure and sequence detection method designed for multi-protocol analysis in the field of protocol reverse engineering, with the aim of mitigating cyber threats such as malware and system hacking. Multi-protocol data, involving two or more undefined protocols, requires effective protocol classification. To address this, our study employs a hierarchical clustering method for multi-protocol classification, enhancing the performance and reducing the computational complexity of the protocol structure and sequence detection algorithm by removing payload of messages. The proposed method is evaluated using both a frequent sequence detection algorithm with a sliding window and a Contiguous Sequential Pattern (CSP) algorithm for protocol structure and sequence detection. Results demonstrate that the inclusion of hierarchical clustering and payload removal in both the frequent sequence detection algorithm and the CSP algorithm leads to notable performance enhancements.

2차원 위상비교 방향탐지를 위한 수신기 설계 및 제작

전종화,조성진,채명호,Jeon, Jonghwa,Jo, Sungjin,Chae, Myoungho 한국군사과학기술학회 2020 한국군사과학기술학회지 Vol.23 No.1

In this paper, a 2-dimensional phase comparison direction finding receiver was designed and fabricated. For 2-D comparison direction finding, direction finding formulas were derived from a uniformly arranged of four antennas. Based on this, a direction finding receiver was designed using Matlab simulink, and the direction finding receiver was fabricated. To analyze the performance of the designed direction finding receiver, the injection direction finding accuracy and simulation results were compared. As a result of the test, the fabricated direction finding receiver showed a maximum of 3° RMS precision, and the result of both tests showed similar trends. Also, it was confirmed that the direction finding accuracy of elevation angle is about 2.7 times better than azimuth angle, and both models performed well within 0.7° RMS at the boresight.

드론 원격조종신호에 대한 재밍 성능 시험

정운섭(Un Seob Jeong),채명호(Myoung Ho Chae),최채택(Chae Taek Choi),황정섭(Jung Sub Hwang),최승호(Seung Ho Chio),박범준(Beom Jun Park) 대한전자공학회 2022 대한전자공학회 학술대회 Vol.2022 No.6