DOI QR코드

DOI QR Code

기지국용 Cross Post-Distortion 평형 선형 전력 증폭기에 관한 연구

A Research on a Cross Post-Distortion Balanced Linear Power Amplifier for Base-Station

  • 최흥재 (전북대학교 정보통신공학과 및 반도체설계교육센터) ;
  • 정희영 ((주)에어포인트) ;
  • 정용채 (전북대학교 정보통신공학과 및 반도체설계교육센터) ;
  • 김철동 (세원텔레텍(주))
  • 발행 : 2007.11.30

초록

본 논문에서는 feedforward와 post-distortion 기법을 이용하여 평형 증폭기 내에서 발생하는 혼변조 왜곡 성분을 제거할 수 있는 새로운 왜곡 상쇄 메커니즘인 cross post-distortion 선형화 기법을 제안한다. 출력 동적 영역과 대역폭 측면에서 제안하는 선형화 방식은 기존의 feedforward 방식에 뒤지지 않는 성능을 가지고 있으면서 상대적으로 높은 효율을 제공한다. 이론적 뒷받침을 위해 제안하는 시스템과 feedforward 방식의 전력 증폭기와 오차증폭기의 전력 용량을 비교 분석하였고, IMT-2000 대역에서 실제 구현을 통하여 이를 실험적으로 뒷받침하였다. 최대 출력 전력 240 W의 기지국용 상용 대전력 증폭기에 적용했을 때, wideband code division multiple access (WCDMA) 4FA 신호에 대하여 평균 출력 전력 40 dBm에서 약 18.6 dB의 개선 효과를 얻었다. 제작된 전력 증폭기는 WCDMA 신호 기준으로 feedforward 방식에 비해 약 2 % 개선된 효율을 보였다.

In this paper, we propose a new distortion cancellation mechanism for a balanced power amplifier structure using the carrier cancellation loop of a feedforward and post-distortion technique. The proposed cross post-distortion balanced linear amplifier can reduce nonlinear components as much as the conventional feedforward amplifier through the output dynamic range and broad bandwidth. Also the proposed system provides higher efficiency than the feedforward. The capacities of power amplifier and error power amplifier in the proposed system are analyzed and compared with those of feedforward amplifier. Also the operation mechanisms of the three kind loops are explained. The proposed cross post-distortion balanced linear power amplifier is implemented at the IMT-2000($f_0=2.14\;GHz$) band. With the commercial high power amplifiers of total power of 240 W peak envelope power fer base-station application, the adjacent channel leakage ratio measurement with wideband code division multiple access 4FA signal shows 18.6 dB improvement at an average output power of 40 dBm. The efficiency of fabricated amplifier Improves about 2 % than the conventional feedforward amplifier.

키워드

참고문헌

  1. S. C. Cripps, Advanced Techniques in RF Power Amplifiers Design, Norwood, MA, Artech House, 2002
  2. P. B. Kenington, R. J. Wilkinson, and J. D. Marvill, 'Power amplification techniques for linear TDMA base station', IEEE Global Telecommunication Conf. Dug., vol. 1, pp. 74-78, Dec. 1992
  3. Fredric H Raab, Peter Asbeck, Steve Cripps, Peter B. Kennington, Zoya B. Popovic, Nick Pothecary, John F. Sevic, and Nathan 0. Sokal, 'Power amplifiers and transmitter for RF and microwave', IEEE Trans. on MTT, vol. 50, no. 3, pp. 814-826, Mar. 2002 https://doi.org/10.1109/22.989965
  4. Mark Billsberry, Melbourne Beach, 'Balanced distortion reduction circuit', United States Patent, Patent no. US 6,734,726 B2, May 2004
  5. Yong-Chae Jeong, Jong-Sik Lim, 'A novel frequency doubler using feedforward technique and defected ground structure', IEEE Microwave and Wireless Components Letters, vol. 14, no. 12, pp. 557-559, Dec. 2004 https://doi.org/10.1109/LMWC.2004.837382
  6. Jae-Hee Han, Duck-Hee Lee, Sangwook Nam, Jong-Sik Lim, Jongsup Yun, and Sungchoon Kang, 'Post-distortion linearizer for multicarrier power amplifiers using a fifth-order error signal generator', Proc. 2001 Asia Pacific Microwave Conference, vol. 1, pp. 272-275, Dec. 2001
  7. Heungjae Choi, Yongchae Jeong, J. Stevenson Kenney, and Chul Dong Kim, 'Cross post-distortion balanced power amplifier', IEEE MTT-S Int. Microwave Symp. Dig., pp. 1115-1118, Jun. 2007
  8. T. O'Sullivan, R. A. York, B. Noren, and P. M. Asbeck, 'Adaptive duplexer implemented using single-path and multipath feedforward techniques with BST phase shifters', IEEE Trans. on MTT, vol. 53, no. 1, pp. 106 -114, Jan. 2005 https://doi.org/10.1109/TMTT.2004.839900
  9. K. J. Parsons, P. B. Kenington, 'Effect of delay mismatch on a feedforward amplifier', Proc. Inst. Elect. Eng., vol. 141, no. 2, pp. 140-144, Apr. 1994
  10. Yong-Chae Jeong, Dal Ahn, Chul-Dong Kim, and Ik-Soo Chang, 'Feedforward amplifier using equal group-delay signal canceller', IEEE MTT-S Int. Microwave Symp. Dig., pp. 1530-1533, Jun. 2006