Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Stochastic characterization and mathematical analysis of feedforward linearizers
Download
index.pdf
Date
2003
Author
Coşkun, Arslan Hakan
Metadata
Show full item record
Item Usage Stats
180
views
0
downloads
Cite This
Feedforward is known to be one of the best methods for power amplifier linearization due to its superior linearization performance and broadband stable operation. However feedforward systems have relatively poor power efficiency and are complicated due to the presence of two nonlinear amplifiers and the requirements of amplitude, phase and delay matching within two different loops. In this thesis stochastic characterization of a simple feedforward system with autocorrelation analysis has been presented for Code Division Multiple Access (CDMA) applications taking the amplitude and delay mismatches into consideration. It has been assumed that, the input signal can be represented as Gaussian noise, main and error amplifiers can be modeled with third order AM/AM nonlinearities and there exists no phase mismatch within the loops. Hence closed form expressions, which relate the main channel and distorted adjacent channel power at any point in the feedforward circuitry to the system parameters, have been obtained. Consequently, a mathematical handy tool is achieved towards specifying the circuit parameters rapidly for optimum linearity performance and efficiency. The developed analytical model has been verified by Radio Frequency (RF) and system simulations. An alternative approach towards modeling feedforward systems for arbitrary signals has also been brought into consideration and has been verified with system simulations.
Subject Keywords
Neural networks (Computer science)
,
Mathematical analysis
,
Stochastic analysis
URI
http://etd.lib.metu.edu.tr/upload/626721/index.pdf
https://hdl.handle.net/11511/13916
Collections
Graduate School of Natural and Applied Sciences, Thesis
Suggestions
OpenMETU
Core
Energy-aware routing algorithms for wireless ad hoc networks with heterogeneous power supplies
Vazifehdan, Javad; Prasad, R. Venkatesha; Onur, Ertan; Niemegeers, Ignas (Elsevier BV, 2011-10-27)
Although many energy-aware routing schemes have been proposed for wireless ad hoc networks, they are not optimized for networks with heterogeneous power supplies, where nodes may run on battery or be connected to the mains (grid network). In this paper, we propose several energy-aware routing algorithms for such ad hoc networks. The proposed algorithms feature directing the traffic load dynamically towards mains-powered devices keeping the hop count of selected routes minimal. We unify these algorithms into...
Software implementations of QoS scheduling algorithms for high speed networks /
Pehlivanlı, Aydın; Schmidt, Şenan Ece; Department of Electrical and Electronics Engineering (2015)
The end to end Quality of Service (QoS) support for the dominating multimedia traffic in the contemporary computer networks is achieved by implementing schedulers in the routers and deploying traffic shapers. To this end, realistic modeling and simulation of these components is essential for network performance evaluation. The first contribution of this thesis is the design and implementation of a C++ simulator QueST (Quality of Service simulaTor) for this task. QueST is a modular cycle accurate simulator w...
Communication Coverage in Wireless Passive Sensor Networks
Bereketli, Alper; Akan, Ozgur B. (2009-02-01)
System lifetime of wireless sensor networks (WSN) is inversely proportional to the energy consumed by critically energy-constrained sensor nodes during RF transmission. In that regard, modulated backscattering (MB) is a promising design choice, in which sensor nodes send their data just by switching their antenna impedance and reflecting the incident signal coming from an RF source. Hence, wireless passive sensor networks (WPSN) designed to operate using MB do not have the lifetime constraints of convention...
Circular arrays of log-periodic antennas for broadband applications
Ergül, Özgür Salih (2006-11-10)
Circular arrays of log-periodic (LP) antennas are designed for broadband applications. A sophisticated electromagnetic simulation environment involving integral equations and fast solvers is developed to analyze the LP arrays both accurately and efficienuy. The resulting matrix equation obtained by the discretization of the electric field integral equation is solved iteratively via the multilevel fast multipole algorithm (MLFMA). Genetic algorithms interacting with MLFMA is employed to optimize the excitati...
Sinus Output 3-Phase Inverter Topology for Improved Drive Efficiency
Ertan, Hulusi Bülent (2014-09-24)
Traditionally electrical drives and uninterruptable power supplies generate pulse width modulated outputs. Harmonic content of such waveforms are known to cause problems. Therefore, it is worthwhile to investigate 3-phase sinus output topologies, which can compete with traditional inverter topologies, regarding performance and cost. In this paper, first some topologies for producing single-phase sinus output are reviewed. Then, the possibility of using these single-phase units for producing 3-phase output i...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
A. H. Coşkun, “Stochastic characterization and mathematical analysis of feedforward linearizers,” Ph.D. - Doctoral Program, Middle East Technical University, 2003.
