DOI QR코드

DOI QR Code

동일 군속도 지연 상쇄기를 이용한 이중 대역 Feedforward 선형 전력 증폭기

Dual-Band Feedforward Linear Power Amplifier Using Equal Group Delay Signal Canceller

  • 발행 : 2007.07.31

초록

본 논문에서는 새로운 구조의 이중 대역 feedforward 선형 전력 증폭기(FFW LPA)의 설계 방법을 제안하였다. 현재까지 이중 대역 FFW LPA 설계의 기술적인 어려움은 단일 대역 FFW LPA에서 사용되는 신호 상쇄기를 이중 대역 동작으로 확장시키기가 쉽지 않았다는 점이다. 따라서 본 논문에서는 이중 대역 동일 군속도 지연 주 신호 상쇄기와 혼변조 왜곡 신호(Intermodulation Distortion: IMD) 상쇄기의 설계 방법, 그리고 이를 이용하여 단일 대역 FFW 기법을 확장한 이중 대역 FFW LPA의 설계 방법을 제안하였다. 제안하는 설계 방식의 효용성을 검증하기 위하여, 동작 대역의 중심 주파수를 기준으로 1.26 GHz 이격된 디지털 셀룰러 대역($f_0=880$ MHz)과 IMT-2000($f_0=2.14$ GHz) 대역 기지국용 이중 대역 feedforward 선형화 시스템을 구현하였다. 각 대역별로 CDMA IS-95A 4FA 신호와 WCDMA 4FA 신호를 인가하여 인접 채널 누설비(Adjacent Channel Leakage Ratio: ACLR)의 개선 정도를 측정한 결과, 디지털 셀룰러 대역에서 평균 출력 전력 41.5 dBm일 때 16.52 dB, IMT-2000 대역에서 평균 출력 전력 40 dBm일 때 18.59 dB의 개선 효과를 동시에 얻을 수 있었다.

In this paper, the first attempt to design a novel structure of dual-band feedforward linear power amplifier(FFW LPA) was presented. Up to now, primary technical difficulty has been the extension of the conventional signal canceller to the dual-band operation. Therefore, we propose the design technique of the dual-band equal group delayed carrier canceller, the dual-band equal group delayed intermodulation distortion(IMD) canceller and the dual-band FFW LPA. The operation frequency bands of the implemented dual-band FFW LPA are digital cellular($f_0=880$ MHz) and IMT-2000($f_0=2.14$ GHz) band, which are separated about 1.26 GHz. With the high power amplifier of 120 W PEP for commercial base-station application, IMD cancellation loop shows 20.45 dB and 25.04 dB loop suppression at each band of operation for 100 MHz. From the adjacent channel leakage ratio(ACLR) measurement with CDMA IS-95A 4FA and WCDMA 4FA signal, we obtained 16.52 dB improvement at the average output power of 41.5 dBm for digital cellular band, and 18.59 dB improvement at the average output power of 40 dBm for IMT-2000 band simultaneously.

키워드

참고문헌

  1. K. Kunihiro, S. Yamanouchi, T. Miyazaki, Y Aoki, K Ikuina, T Ohtsuka, and H. Hida, 'A diplexer-matching dual-band power amplifier LTCC module for IEEE 802.11a/b/g wireless LANs', IEEE Radio Frequency Integrated Circuits Symposium Digest, pp. 303-306, Jun. 2004
  2. A. Adar, J. DeMoura, H. Balshem, and J. Lott, 'A high efficiency single chain GaAs MESFET MMIC dual-band power amplifier for GSM/DCS handsets', IEEE Gallium Arsenide Integrated Circuit Symposium Digest, pp. 69-72, Nov. 1998
  3. S. C. Cripps, Advanced Techniques in RF Power Amplifiers Design, Norwood, MA, Artech House, 2002
  4. F. H. Raab, P. Asbeck, S. C. Cripps, P. B. Kenington, Z. B. Popovi , V. Pothecary, J. F. Sevic, and N. O. Sokal, 'Power amplifiers and transmitters for RF and microwave', IEEE Trans. Microwave Theory & Tech., vol. 50, no. 3, pp. 814-826, Mar. 2002 https://doi.org/10.1109/22.989965
  5. Yong-Chae Jeong, Young-Jean Song, and In-Ju Oh, 'A novel adaptive feedforward amplifier using an analog controller', Microwave Journal, vol. 46, no. 4, pp. 76-85, Apr. 2003
  6. Si-Gyun Jeong, Seong-Hoon Jeong, Jeong-Hyeon Cha, Yong-Chae Jeong, and Chul-Dong Kim, 'A feedforward power amplifier with loops to reduce RX band noise and intermodulation distortion', Microwave Journal, vol. 45, no. 1, pp. 80-91, Jan. 2002
  7. Heung-Jae Choi, Hee-Young Jeong, Young Kim, Jong-Sik Lim, Chul-Dong Kim, and Yong-Chae Jeong, 'Dual-band predistortion power amplifier for digital cellular and IMT-2000 base-station application', Asia Pacific Microwave Conference Proceeding, vol. 1, pp. 208-211, Dec. 2005
  8. Yong-Chae Jeong, Dal Ahn, Chul-Dong Kim, and Ik-Soo Chang, 'Feedforward amplifier using equal group-delay signal canceller', To be published on IEEE MTT-S Digest, 2006
  9. Y. Konoshi, I. Awai, and Y. Fukuoka, 'A directional coupler of a vertically installed planar circuit structure', IEEE Trans. on Microwave Theory and Techniques, vol. 36, no. 6, pp. 1057-1063, Jun. 1988 https://doi.org/10.1109/22.3632
  10. E. G. Cristal, L. Young, 'Theory and table of optimum symmetrical TEM mode coupled transmission line directional coupler', IEEE Trans. on Microwave Theory and Techniques, vol. 13, no. 9, pp. 544-558, Sep. 1965 https://doi.org/10.1109/TMTT.1965.1126050
  11. J. Reed, G. J. Wheeler, 'A method of analysis of symmetrical four-port networks microwave theory and techniques', IEEE Trans. on Microwave Theory and Techniques, vol. 4, no. 4, pp. 246-252, Oct. 1956 https://doi.org/10.1109/TMTT.1956.1125071
  12. In-Seon Kim, Cheol-Soo Lee, 'A study on broadband hybrid design using vertically installed planar circuit with partially removed ground plane', Journal of Korea Electromagnetic Engineering Society, vol. 16, no. 7, pp. 661-670, Jul. 2005