수정곡면 이중 옵셋 그레고리안 안테나 설계

문성익,양두영 제주대학교 산업기술연구소 1999 尖端技術硏究所論文集 Vol.10 No.2

In this paper, design procedure of the shaped dual offset gregorian antenna is proposed. The electric field distribution of aperture for main reflector is calculated by using taper factor and cos-q factor. The approximated equations of parameters are derived by the geometrical optics theory which determines the geometrical structure of the antenna. The results using the taper factor show characteristics that maximum side lobe level, spillover efficiency and illumination efficiency are -23dB, 89% and 89%. In case of the cos-q factor, they show that those are -27dB, 91% and 91%, respectively. Finally, the shaped dual offset gregorian antenna system by using cos-q factor with the improved characteristics has been designed.

모드 정합법을 이용한 직교모드 변환기 해석 및 설계

문성익,양두영 濟州大學校 情報通信硏究所 2000 情報通信硏究所論文集 Vol.3 No.-

In this paper. the orthomode transducer of the antenna feed system is analyzed and designed. It consists of combining the common circular waveguide with the two sub-rectangular waveguide. The size of the circular and the rectangular waveguide are WC59. WR62 and the orthomode transducer considered the 13th high-order mode. From the boundary condition for the electromagnetic field. the scattering parameters are derived from the Hybrid electromagnetic mode theory. The computed results are compared with HFSS of 3D simulation tool for the microwave circuits. The results show a good characteristic that the S_(11) and S_(22) are below -15.5dB and S_(33) S_(44) are below -14dB in the range of 14.5~16.5GHz.

수정곡면 이중 옵셋 그레고리안 안테나 설계

문성익,양두영 濟州大學校 産業技術硏究所 1999 산업기술연구소논문집 Vol.10 No.2

In this paper, design procedure of the shaped dual offset gregorian antenna is proposed. The electric field distribution of aperture for main reflector is calculated by using taper factor and cos-q factor. The approximated equations of parameters are derived by the geometrical optics theory which determines the geometrical structure of the antenna. The results using the taper factor show characteristics that maximum side lobe level, spillover efficiency and illumination efficiency are -23dB. 89% and 89%. In case of the cos-q factor, they show that those are -27dB. 91% and 91%. respectively. Finally, the shaped dual offset gregorian antenna system by using cos-q factor with the improved characteristics has been designed.

원형도파관과 구형도파관간의 T-접합 분기회로 해석

문성익,허광삼,김윤영,양두영 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.1

In this paper, the T-junction branch network of the orthomode transducer is analyzed. The T-junction blanch network consists of the cylindrical common waveguide and the rectangular sub-waveguide. Using the vector potential of each region, the hybrid mode is considered. Based on the derived electromagnetic components, scattering parameters of the T-junction branch network are calculated. The cylindrical waveguide size and the rectangular waveguide size are WR62 and WC55. In order to analyze the discontinuity of the T-junction branch network, high order mode of the branch region is considered the 15th. From the results, the transmission coefficient. S31 and S21 show -3dB, the reflection coefficient, S11 and S33 are -10dB, -8dB in the range of 13.3GMz∼16GHz.

X밴드용 다이폴 급전 평면배열 안테나 설계 및 제작

문성익,양두영,Mun, Seong-Ik,Yang, Du-Yeong 대한전자공학회 2002 電子工學會論文誌-TC (Telecommunications) Vol.39 No.5

본 논문에서는 기존외 야기-우다 안테나 배열이론을 마이크로스트립 안테나에 접목시킨 X밴드용 다이폴 급전 평면배열 안테나를 설계하고 제작하였다. 그리고 넓은 대역폭을 갖는 무선통신 시스팀에 쉽게 적용시킬수 있는 다이폴 급전 평면배열 안테나의 설계 절차에 대하여 기술하였다. 또한 FDTD 수치해석법을 이용하여 안테나의 복사특성, 반사손실과 대역폭을 개선시켰으며 제작을 통해 평면형 안테나 해석의 타당성을 입증하였다. 제작한 결과, 10GHz의 중심주파수에서 안테나의 이득은 4.9dBi이고 대역폭은 약 40%, 전후방비는 16dB, E면과 H면의 반 전력 빔폭은 각각 117°와 156°이다. VSWR<2를 기준으로 했을 때, 7.4GHz∼11.88GHZ의 주파수 범위에서 측정결과와 이론적인 결과가 비교적 잘 일치하였다. In this paper, the dipole-fed planar array antenna applied Yagi-Uda antenna away theory to microstrip antenna is designed and fabricated at X-band. The design procedure of the dipole-fed planar array antenna with the wide bandwidth is presented to be easily practiced to a wireless communication system. The radiation pattern, return loss and bandwidth of the antenna are improved by the finite differential time domain(FDTD) numerical method. The propriety of analysis of planar dipole antenna is proved from the measured data. From the measured results, the antenna maximum gain is 4.9dBi at center frequency of 10GHz and frequency bandwidth is about 40%. Front-to-back ratio is 16dB, and half-power beam-width of E-plane and H-plane are 117$^{\circ}$and 156$^{\circ}$, respectively. When VSWR of antenna is less than 2, the measured results are agreed well with the theoretical values in the frequency range from 7.4GHz to 11.88GHz.

Ku 밴드 안테나 급전시스팀 설계

문성익,이정란,양두영 濟州大學校 産業技術硏究所 1998 산업기술연구소논문집 Vol.9 No.2

In this paper. design of the antenna feed system for Ku-band is presented by TE_(mn)^(x) mode theory. The antenna feed system consists of diplexer combined with transmitting filter and receiving filter, OMT(Othogonal Mode Transducer) and polarizer. These filters are designed by the insertion loss method which is applied to the mode matching method. Matching elements in the inner waveguide set to reduce mismatching conditions on the discontinuity imposed by T-junction, so that a diplexer is optimized and has the best property. The optimum filter appeared characteristics that reflected power is about -2OdB in the receiving and the transmitting passband. The differential phase shift of the corrugated polarizer combined with OMT achieved 90°±1° within 14.0 - 14.5㎓ frequency-band. The maximum VSWR is only about 1.02 and axial ratio(AR) is about 1.01. The designed feed system has suitably separated between the polarized wave and the frequency bandwidth.

MUSIC 알고리즘을 이용한 적응 빔 성형에 관한 연구

문성익,이광식,양두영 제주대학교 공과대학 첨단기술연구소 2003 尖端技術硏究所論文集 Vol.14 No.1

In order to estimate DOA(Direction Of Arrival) of signal, the adaptive beam forming algorithm based on MUSIC(Multiple Signal Classification) is studied and analyzed. The eigenvalues for the signal component and the noise component are obtained from correlation matrix of the received signal by array antenna. The eigenvalues classified the signal components into the noise components decide the power spectrum of the received signal. From the results, DOA is estimated by the signal and noise spatial vector, and the steering beam pattern is found by weight vectors calculated from the spatial vector, effectively.

마이크로파 방송 중계기용 구형창 도파관 필터 설계 및 제작

문성익,양두영 한국전자파학회 1999 한국전자파학회논문지 Vol.10 No.4

본 논문에서는 WR137 표준 도파관을 사용한 마이크로파 방성 중계기용 필터를 설계하기 위하여 구형 도파관의 불연속 특성해석에 적합한 수정된 ${TE^x}_{mn}$ 모드정합법을 적용하였다. 정확한 해와 수렴속도를 개선시키기 위해 수정된 ${TE^x}_{mn}$ 모드정합법에 공액경사(Conjugate Gradient) 최적화 방법을 적용하여 47 MHz 대역폭을 갖는 마이크로파 방송 중계기용 구형창 도파관 필터를 설계.제작하였다. 그 결과 통과대역 내에서 $S_{11}$과 $S_{21}$은 각각 최대 -28dB, -0.56dB로 나타났고, 정재파비는 1.02 이하로 나타나 양호한 구형창 필터를 제작할 수 있었다. In this paper, design of rectangular iris waveguide filter for the microwave broadcasting transponder using WR137 is applied to the modified ${TE^x}_{mn}$ mode theory in order to exactly analyze the characteristic of the waveguide discontinuity. We designed and fabricated the rectangular iris waveguide filter with the bandwidth 47 MHz for the microwave broadcasting transponder applied the conjugate gradient method to the modified ${TE^x}_{mn}$ mode theory. The results show a good characteristics that the $S_{11}$ and $S_{21}$ are -23 ㏈, -0.56 ㏈ and the maximum VSWR is below 1.02 in the passband.

원형도파관과 구형도파관간의 T-접합 분기회로 해석

문성익,김윤영,허광삼,양두영 濟州大學校 産業技術硏究所 2000 산업기술연구소논문집 Vol.11 No.1

In this paper, the T-junction branch network of the orthomode transducer is analyzed. The T-junction branch network consists of the cylindrical comnion waveguide and the rectangular sub-waveguide. Using the vector potential of each region. the hybrid mode is considered Based on the derived electromagnetic components. scattering parameters of the T-junction branch network are calculated. The cylindrical waveguide size and the rectangular waveguide size are WR62 and WC55. In order to analyze the discontinuity of the T-junction branch network. high order mode of the branch region is considered the 15th. From the results. the transmission coefficient. S_(31) and S_(21) show -3dB. the reflection coefficient. S_(11) and S_(33) are -10dB. -8dB in the range of 13.3GHz-16GHz.

Ku 밴드 안테나 급전 시스팀 설계

문성익,이정란,양두영 濟州大學校 工科大學 産業技術硏究所 1998 尖端技術硏究所論文集 Vol.9 No.2

In this paper, design of the antenna feed system for Ku-band is presented by TEmn χ mode theory. The antenna feed system consists of diplexer combined with transmitting filter and receiving filter, OMT( Othogonal Mode Transducer) and polarizer. These filters are designed by the insertion loss method which is applied to the mode matching method. Matching elements in the inner waveguide set to reduce mismatching conditions on the discontinuity imposed by T-junction. so that a diplexer is optimized and has the best property. The optimum filter appeared characteristics that reflected power is about -2OdB in the receiving and the transmitting passband. The differential phase shift of the corrugated polarizer combined with OMT achieved 90° ± 1° within 14.0 - 14.5GHz frequency-band. The maximum VSWR is only about 1.02 and axial ratio(AR) is about 1.01. The designed feed system has suitably separated between the polarized wave and the frequency bandwidth.