藉準非線性模型逼近和Volterra-series方法對砷化鎵假晶式高電子遷移率電晶體作特性化分析

Characterization of GaAs pHEMT by Quasi-Nonlinear Modeling Approach with Volterra-Series Analysis

陳冠宇(Kuan-Yu Chen)

指導教授 ： 黃 建 彰

元智大學/電機通訊學院/電機工程學系/博士(2008年)

https://doi.org/10.6838/YZU.2008.00046

摘要

本論文敘述假晶式砷化鎵高電子遷移率電晶體非線性轉導與電容值的完整萃取方法並應用在Volterra級數電路分析。非線性轉導的萃取計算需要在不同的衰減器下對元件作低頻的諧波大小與相位的實驗。而對非線性電容的計算方面，是在量測不同偏壓下的散射參數後，對此電容趨勢作曲線逼近方式，推導出非線性的電容值。這些三階諧波項的非線性參數是藉由兩相鄰信號輸入的測試方式驗證非線性參數正確性，其偏壓從180mA變化至250mA，功率掃描從-9.3dBm至6.7dBm。本研究提出的非線性參數分析方式對於現代數位無線通訊系統中所需之低交互調變失真功率放大器設計相當具有參考的價值。

關鍵字

假晶式砷化鎵高電子遷移率電晶體 ； 元件特性化分析 ； 非線性失真 ； Volterra級數 ； 降低交互調變失真效應

並列摘要

In this dissertation, explicit extracting procedures for nonlinear transconductances and capacitances of GaAs pseudomorphic high electron mobility transistors (pHEMTs) are presented for Volterra-series circuit analysis. Nonlinear transconductances are acquired by the low-frequency harmonic measurements with the associated phase polarities at various attenuations. Biased-dependent scattering parameter (S-parameter) measurements are utilized with the curve-fitting processes to deduce the nonlinear capacitances. The extracted data up to third order nonlinearities are validated by the two-tone signal tests in a bias-range of 180 mA to 250 mA and a power sweep of ?{9.3 dBm to 6.7 dBm, respectively. This device characterization is quite useful for intermodulation reduction of power amplifier designs in modern digital wireless communications.

並列關鍵字

GaAs pHEMT ； device characterization ； nonlinear distortion ； Volterra-Series ； intermodulation reduction

參考文獻

[1] J. J. Brown, J. A. Pusl, M. Hu, A. E. Schmitz, D. P.

L. D. Nguyen, “High efficiency GaAs-based pHEMT C-

band power amplifier,” IEEE Microwave Guided Wave

[2] S. H. Chen, E. Y. Chang and Y. C. Lin, “2.4 V-

operated enhancement mode pHEMT with 32 dBm output