Nonlinear Distortion Analysis of 2.4GHz Power Amplifier for IEEE 802.11g OFDM Wireless LAN

IEEE 802.11g OFDM 무선랜용 2.4GHz 전력증폭기의 비선형 왜곡분석

  • Oh Chung Gyun (Dept. of Electronics Engineering, University of Incheon) ;
  • Choi Jae Hong (Dept. of Electronics Engineering, University of Incheon) ;
  • Koo Kyung Heon (Dept. of Electronics Engineering, University of Incheon)
  • Published : 2005.03.01

Abstract

The OFDM modulation and transmission block have been modeled in order to analyse the relationship between the 2.4GHz power amplifier distortion and output ACPR for the IEEE 802.11g wireless LAN. The nonlinear characteristic of the power amplifier has been modeled as AM-to-AM and AM-to-PM using the behavioral model, and the output spectrum is analysed with the phase distortion variation. Also, amplifier back-off value from P1dB to satisfy the required IEEE 802.11g standard spectrum mask s been simulated with modeled phase distortion, and the simulation data have been compared to the measured result by using the pre-distortion technique.

무선랜용 전력증폭기의 비선형특성과 출력 ACPR 관계를 분석하기위해, 최대 54Mbps의 전송속도를 가지는 IEEE 802.11g OFDM 변조부와 송신부를 모델링하였다. 2.4GHz 전력증폭기의 비선형특성은 behavioral model을 이용하여 An-to-AM과 AM-to-PM으로 모델링하였으며, 위상 왜곡특성에 따른 출력스펙트럼 특성을 해석하였다. IEEE 802.11g 무선랜 시스템의 요구 출력스펙트럼 마스크를 만족하기위한 P1dB로부터 back-off값을 구하기 위하여 모델링한 위상왜곡 크기에 따른 전력증폭기의 ACPR 특성을 시뮬레이션하고 사전위상 왜곡방식을 이용하여 증폭기의 위상왜곡을 변화시키며 측정한 결과와 시뮬레이션 특성을 비교 제시하였다.

Keywords

References

  1. Wireless LAN Medium Access Control(MAC) and Physical Layer specifications, IEEE Std. 802.11a/b/g, 1999/1999/2003
  2. S. Chen, W. Panton and R. Gilmore, 'Effects of Nonlinear Distortion on CDMA Communication Systems,' IEEE MTT-S Int. Microwave Symp. Dig., pp.775-778, 1996 https://doi.org/10.1109/MWSYM.1996.511053
  3. J. Sevic and J. Staudinger, 'Simulation Power Amplifier Adjacent Channel Power Ratio for DigitalWireless Communication Systems,' IEEE MTT -S Int. Microwave Symp Dig pp . 681-684, 1996 https://doi.org/10.1109/VETEC.1997.600415
  4. H. Gutierrez, K. Grad and M. Steer, 'Spectral Regrowth in Microwave Amplifier Using Transformation of Signal Statistics,' IEEE MTT-S Int. Microwave Symp. Dig., pp. 985-998, 1999 https://doi.org/10.1109/MWSYM.1999.779551
  5. S. Cripps, RF Power Amplifiers for Wireless Communications, Artech House, 1999
  6. S. Mass, Nonlinear Microwave Circuits, Artech House, 1998
  7. R. A. Minasian, 'Intermodulation Distortion Analysisof MESFET Amplifier Using Volterra Series Representation ,' IEEE Trans. Microwave Theory Tech., vol.28, pp.1-8, Jan. 1980 https://doi.org/10.1109/TMTT.1980.1129998
  8. J. Sevic, K. Burger and M. Steer, 'A Novel Envelope Termination Load Pull Method for ACPR Optimization of RF/Microwave Power Amplifiers,' IEEE MTT-S Int. Microwave Symp. Dig., pp.723-726, 1998 https://doi.org/10.1109/MWSYM.1998.705093
  9. Wireless Lan Medium Acces Control (MAC) and Physical Layer (PHY) Specifications, IEEE Computer Society, July 1996
  10. M. Nishida, S. Murai, H. Uda, H. Tominiga, T. Sawai and A. Ibaraki, 'A High Efficiency GaAs Power Amplifier Module with a Single Voltage for Digital Cellular Phone Systems,' IEEE MTT-S Int. Microwave Symp. Dig., pp.743-746, 1997 https://doi.org/10.1109/MWSYM.1998.705028
  11. J. S. Park, S. R. Park, H. J. Roh and K. H. Koo, 'Power Amplifier Back-off Analysis with AM-to-PM for Millimeter-wave OFDM Wireless LAN,' Proc. of RAWCON2001, pp.189-192, 2001 https://doi.org/10.1109/RAWCON.2001.947603