Novel DSP algorithms for adaptive feedforward power amplifier design.

Chan Kwok-po.Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.Includes bibliographical references.Abstracts in English and Chinese.Abstract --- p.iAcknowledgement --- p.iiiChapter Chapter 1 --- Introduction --- p.1Chapter Chapter 2 --- Characterization of Nonlinearity in Power Amplifier --- p.6Chapter 2.1. --- Ideal Amplifier Representation --- p.6Chapter 2.2. --- Nonlinear Amplifier Representation --- p.7Chapter 2.2.1 --- Series Representation --- p.7Chapter 2.2.2 --- AM-AM and AM-PM Distortion --- p.7Chapter 2.2.3 --- Two-tone Intermodulation --- p.9Chapter 2.2.4 --- Nonlinearity on Digital Modulation Formats --- p.11Chapter Chapter 3 --- Linearization Techniques --- p.13Chapter 3.1. --- Power Back-off --- p.14Chapter 3.2. --- Feedback Technique --- p.15Chapter 3.3. --- Pre-distortion Technique --- p.16Chapter 3.4. --- Feed-forward Technique --- p.18Chapter 3.5. --- Linearization Systems with Signal Processing --- p.19Chapter 3.5.1 --- Envelope Elimination and Restoration (EER) --- p.19Chapter 3.5.2 --- Linear Amplification Using Nonlinear Components (LINC) --- p.20Chapter 3.5.3 --- Combined Analogue-locked Loop Universal Modulator (CALLUM) --- p.21Chapter 3.5.4 --- Linear Amplification Employing Sampling Techniques (LIST) --- p.21Chapter 3.6. --- Other Linearization Techniques --- p.22Chapter Chapter 4 --- Feed-forward Power Amplifier System --- p.23Chapter 4.1. --- General Description --- p.23Chapter 4.2. --- Adaptive Feed-forward Power Amplifier System --- p.25Chapter 4.2.1 --- Power Minimization --- p.28Chapter 4.2.2 --- Pilot Injection Technique --- p.29Chapter 4.2.3 --- Look-up-table Technique (Temperature Compensation) --- p.31Chapter 4.2.4 --- Correlation Based Feedback Control (Dual-loop) --- p.32Chapter 4.2.5 --- Correlation Based Feedback Control (Triple-loop) --- p.34Chapter 4.2.6 --- Digital Implementation on Adaptive FFPA --- p.35Chapter Chapter 5 --- DSP-based Adaptive FFPA Analysis --- p.37Chapter 5.1. --- System Architecture --- p.37Chapter 5.2. --- System Modeling --- p.39Chapter 5.3. --- Principle of Adaptation --- p.40Chapter 5.3.1 --- Adaptation in Error Extraction Loop --- p.40Chapter 5.3.2 --- Adaptation in Main-tone Suppression Loop --- p.43Chapter 5.3.3 --- Adaptation in Distortion Cancellation Loop --- p.44Chapter 5.3.4 --- Complex Adaptation --- p.46Chapter 5.4. --- Adaptation Performance Analysis --- p.47Chapter 5.4.1 --- Condition for Convergence --- p.47Chapter 5.4.2 --- Rate of Convergence --- p.48Chapter 5.4.3 --- Misadjustment --- p.49Chapter 5.4.4 --- Summary of the System Performance --- p.51Chapter 5.5. --- System Design Consideration --- p.51Chapter 5.5.1 --- Quadrature Sampling --- p.51Chapter 5.5.2 --- Data Processing --- p.52Chapter 5.6. --- Sensitivity Analysis --- p.55Chapter 5.6.1 --- Vector Representation --- p.55Chapter 5.6.2 --- Amplitude and Phase Matching --- p.56Chapter 5.6.3 --- Time-delay Matching --- p.58Chapter 5.7. --- Analog-to-digital Interface: Design Consideration --- p.60Chapter 5.7.1 --- Sampling Rate Consideration --- p.60Chapter 5.7.2 --- Finite Word-length --- p.61Chapter 5.8. --- Digital-to-analog Interface: Design Consideration --- p.63Chapter Chapter 6 --- New DSP Algorithms for High Performance Adaptive FFPA --- p.67Chapter 6.1. --- Variable Loop-gain Algorithm --- p.67Chapter 6.2. --- Variable Step-size Algorithm --- p.71Chapter 6.3. --- Least-mean-fourth Algorithm --- p.74Chapter Chapter 7 --- Implementation of DSP-based Adaptive FFPA --- p.79Chapter 7.1. --- Hardware Construction --- p.79Chapter 7.2. --- Experimental Results: LMS Algorithm --- p.82Chapter 7.3. --- Experimental Results: Variable Loop-gain Algorithm --- p.86Chapter 7.4. --- Experimental Results: Variable Step-size Algorithm --- p.88Chapter 7.5. --- Experimental Results: Lesat-mean-fourth Algorithm --- p.90Chapter Chapter 8 --- Conclusion --- p.92Appendix I Matlab Program for Computer Simulation of Adaptive FFPA --- p.A-lAppendix II DSP Program for Experimental Adaptive FFPA --- p.A-5References --- p.R-1Author's Publications --- p.AP-

OFDM based air interfaces for future mobile satellite systems

This thesis considers the performance of OFDM in a non-linear satellite channel and mechanisms for overcoming the degradations resulting from the high PAPR in the OFDM signal in the specific satellite architecture. It was motivated by new S-DMB applications but its results are applicable to any OFDM system via satellites. Despite many advantages of OFDM, higher PAPR is a major drawback. OFDM signals are therefore very sensitive to non-linear distortion introduced by the power amplifiers and thus, significantly reduce the power efficiency of the system, which is already crucial to satellite system economics. Simple power amplifier back-off to cope with high OFDM PAPR is not possible. Two transmitter based techniques have been considered: PAPR reduction and amplifier linearization.EThOS - Electronic Theses Online ServiceGBUnited Kingdo