微波仿真论坛加州大学RF功放设计实例.ppt



《微波仿真论坛加州大学RF功放设计实例.ppt》由会员分享,可在线阅读,更多相关《微波仿真论坛加州大学RF功放设计实例.ppt(15页珍藏版)》请在装配图网上搜索。
1、Power Amplifier Nonlinearity Estimation and Predistortion with Correlation Techniques Mingyuan Li, Ian Galton, Larry Larson, Peter Asbeck University of California, San Diego La Jolla, CA 92093-0407,Outline,Nonlinearity extraction in frequency and time domain Correlation techniques for nonlinearity e
2、stimation Mathematical analysis and simulation results Application in adaptive predistortion and measured results Summary and conclusion,AM-AM and AM-PM nonlinearity,Measurement of Intersils ISL3990 Dual Band PA,Look Up Table behavioral model,Behavioral model,Complex polynomial curve fitting model,S
3、ingle tone and two-tone power sweep measurement,Gain and phase vs input power,Gain and phase values vs envelope amplitude r(t),Pro: Simple to characterize and analyze nonlinearity Con: 1. Not actual signal 2. Cant test during normal operation conditions,,Intermodulations vs input power,Pro: Actual s
4、ignal, test during PA operation Con: 1. High resolution and speed ADC 2. Large memory 3. Considerable DSP,Time-domain CDMA envelope test,Gain vs. Pin using time-domain captured data,Phase vs. Pin using time-domain captured data,Vout (red) vs. vin(blue) (a) real part (b) imaginary part,(a),(b),Assess
5、 nonlinearity in adaptive predistortion,Correlation techniques for nonlinearity estimation,Basic idea,Nonlinearity comes from output with 3rd,5th order dependency on input. Create test signal which also has 3rd,5th order dependency on input. Extract nonlinearity by proper correlation of output and t
6、est signal,Advantages Actual signal in real operation conditions Low hardware and power consumption,,Stest is uncorrelated with linear(Vin) Stest is correlated with nonliear(Vin),Correlation mathematical analysis,Assumptions Quasi-memoryless Polynomial model truncated at the 5th order,,Application t
7、o IS-95 forward link transmitter,,,,I,XI,Complex power series analysis,Real correlation value,,,,,,Imag correlation value,Power correlation value,,,Polynomial coefficients extraction by correlation,Comparison of correlation with other techniques,,,,,,,Construct AM_AM and AM_PM using polynomial coeff
8、icients derived by correlations,Different order with different slopes,Comparison of two-tone and correlation,Correlation experimental measurements,Intersils ISL3990 PA 5 Channel PN with 48-tap FIR and Length is 217 Sampling rate is 4*1.2288MHz,(a)First order II,(b)Third order IQ,(c) Fifth order II,(
9、d)Power correlation vs. Pin,Adaptive predistortion application,,Predistortion architecture,Using the correlation extracted values P3corr and P5corr as an object function to adaptively change predistorters coefficients,Adaptive search algorithm(Hooke &Jeeves),Contour of correlation values vs. predist
10、ortion coefficients,Measurement results (1),Amplifier before predistortion is at (b3r,b3i,b5r,b5i=0) pointPin=-10dBm,3rd correlation values(dB) vs. b3,3rd correlation values(dB) vs. b5,Acpr750kHz(dBc) vs. b3,Acpr750kHz(dBc) vs. b5,ISL3990 PA P1db= -10dBm Psat=10dBm Pmax=24.5dBm,Measurement results (
11、2),Magenta curve has larger correlation values and worse ACPR Green curve has smaller correlation values and better ACPR ACPR difference of 14.3dB750kHz 4.8dB1980kHz,,,before PD,after PD,Magenta before PD, Green after PD Pin=-10dBm,Summary and conclusion,Simple correlation techniques have been used
12、to estimate nonlinearity Simulation and measurement results show promise of technique Application in forward link adaptive predistortion transmitter was shown experimentally Optimization algorithm was developed to adaptively change coefficients For future, expect that simple analog correlation circuit can be implemented and memory effects can be considered,
- 温馨提示:
1: 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
2: 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
3.本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
5. 装配图网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。