IMT-2000 중계기용 전력증폭기 설계

허광삼,문성익,김흥수,양두영 濟州大學校 産業技術硏究所 2001 산업기술연구소논문집 Vol.12 No.1

This paper deals with designing the mobile station power amplifier of IMT-2000 using analog predistortion method. The power amplifier made up of 3-stage class-AB amplifiers in cascade. By choosing the final stage as the balanced structure. the output linearity is enhanced. The balanced structure of amplifier is composed of the Wilkinson power divider and combiner. Therefore. to compensate for the linearity of the power amplifier. pre-distorter circuit is inserted in front of 3-stage amplifier. The pre-distorter is implemented using parallel Schotty diode. The optimized linear power amplifier is cornposed of these pre-distorter and 3-stage power amplifier.

전치왜곡방식을 이용한 선형 전력증폭기 설계

허광삼,문성익,양두영 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.2

This paper deals with designing the linear power amplifier using MESFET and Schottky diode. The power amplifier is designed to be ensure 3-W linear output using MESFET, and made up of 3-stage class-AB amplifiers in cascade. By choosing the final stage as the balanced structure, the output linearity is enhanced. The balanced structure of amplifier is composed of the Wilkinson power divider and combiner. In the designed 3-stage amplifier, when the input power is lower than -5dBm, power gain is 38dB. And it rapidly decreases as the input power increases larger than -5dBm. Therefore, to compensate for decreasing the gain, pre-distorter circuit is inserted in front of 3-stage amplifier. The pre-distorter is implemented using parallel Schottky diode. The optimized linear power amplifier is composed of these pre-distorter and 3-stage power amplifier. As a result, when the maximum input power is 9dBm, the 1-dB gain compression point of linear power amplifier, P1dB, is 37.61dBm

전치왜곡방식을 이용한 선형 전력증폭기 설계

허광삼,문성익,양두영 濟州大學校 産業技術硏究所 2000 산업기술연구소논문집 Vol.11 No.2

This paper deals with designing the linear power amplifier using MESFET and Schottky diode. The power amplifier is designed to be ensure 3-W linear output using MESFET. and made up of 3stage class-AB amplifiers in cascade. By choosing the final stage as the balanced structure. the output linearity is enhanced. The balanced structure of amplifier is composed of the Wilkinson power divider and combiner. In the designed 3-stage amplifier. when the input power is lower than -5dBm. power gain is 38dB. And it rapidly decreases as the input power increases larger than -5dBm. Therefore. to compensate for decreasing the gain. pre-distorter circuit is inserted in front of 3stage amplifier. The pre-distorter is implemented using parallel Schottky diode. The optimized linear power amplifier is composed of these pre-distorter and 3-stage power amplifier. As a result. when the maximum input power is 9dBm. the 1-dB gain compression point of linear power amplifier. P_(ldB). is 37.61dBm

IMT-2000 중계기용 전력증폭기 설계

허광삼,문성익,김홍수,양두영 제주대학교 산업기술연구소 2001 尖端技術硏究所論文集 Vol.12 No.1

This paper deals with designing the mobile station power amplifier of IMT-2000 using analog predistortion method. The power amplifler made up of 3-stage class-AB amplifiers in cascade. By choosing the final stage as the balanced structure, the output linearity is enhanced. The balanced structure of amplifier is composed of the Wilkinson power divider and combiner. Therefore, to compensate for the linearity of the power amplifier, pre-distorter circuit is inserted in front of 3-stage amplifier. The pre-distorter is implemented using parallel Schotty diode. The optimized linear power amplifier is composed of these pre-distorter and 3-stage power amplifier.

IMT-2000용 전력증폭기 설계

허광삼(Kwang-Sam Heo),문성익(Seong-Ig Moon),김홍수(Heung-Soo Kim),양두영(Doo-Yeong Yang) 한국통신학회 2001 한국통신학회 학술대회논문집 Vol.2001 No.7

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.

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.

WLL 기지국용 다운 컨버터 설계

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

In this paper, A down converter to convert RF signal into IF signal is designed at the WLL base-station. It consists of low noise amplifier module and down mixer module. The low noise amplifier module is composed of three-stage and a feedback circuit is added in the first-stage low noise amplifier in order to obtain unconditional stability and good flatness. The configuration of the down mixer module is a single-ended type gate mixer. For the good isolation characteristic of each port, a bandpass filter and a lowpass filter are inserted in the input and output port. To design the down converter without the IF power amplifier, it is important to maximize conversion gain. So the down converter of this paper is designed for the purpose of obtaining a high conversion gain. From the results, the IF output power is -12.68dBm when the LO and the RF power level are 7dBm and -80dBm, respectively. Also when the LO power level is 7dBm, P1dB is -0.19dBm, and the RF input power range shows 70dB on wide operating range.

WLL 기지국용 다운 컨버터 설계

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

In this paper, A down converter to convert RF signal into IF signal is designed at the WLL basestation. It consists of low noise amplifier module and down mixer module. The low noise amplifier module is composed of threestage and a feedback circuit is added in the first-stage low noise amplifier in order to obtain unconditional stability and good flatness. The configuration of the down mixer module is a single-ended type gate mixer. For the good isolation characteristic of each port, a bandpass filter and a lowpass filter are inserted in the input and output port. To design the down converter without the IF power amplifier. it is important to maximize conversion gain. So the down converter of this paper is designed for the purpose of obtaining a high conversion gain. From the results, the IF output power is -12.68dBm when the LO and the RF power level are 7dBm and -80dBm. respectively. Also when the LO power level is 7dBm. PldB is -0.19dBm. and the RF input power range shows 70dB on wide operating range.