Chaotic digital modulation and demodulation

Öztürk, Uygar
This thesis considers a communication system with chaotic modulation. Noise-like signals are generated by chaotic systems with different parameters to modulate binary digital signals. Demodulation is performed by both the Extended Kalman Filter (EKF) and Optimum Decoding Based Smoothing Algorithm (ODSA). Simulations are performed using both of these algorithms for different parameters affecting the performance of the communication system. Simulation results of these algorithms are compared.


Nonlinear estimation techniques applied to econometric problems
Aslan, Serdar; Demirbaş, Kerim; Department of Electrical and Electronics Engineering (2004)
This thesis considers the filtering and prediction problems of nonlinear noisy econometric systems. As a filter/predictor, the standard tool Extended Kalman Filter and new approaches Discrete Quantization Filter and Sequential Importance Resampling Filter are used. The algorithms are compared by using Monte Carlo Simulation technique. The advantages of the new algorithms over Extended Kalman Filter are shown.
Signal reconstruction from nonuniform samples
Serdaroğlu, Bülent; Tuncer, Temel Engin; Department of Electrical and Electronics Engineering (2005)
Sampling and reconstruction is used as a fundamental signal processing operation since the history of signal theory. Classically uniform sampling is treated so that the resulting mathematics is simple. However there are various instances that nonuniform sampling and reconstruction of signals from their nonuniform samples are required. There exist two broad classes of reconstruction methods. They are the reconstruction according to a deterministic, and according to a stochastic model. In this thesis, the mos...
Multi-tone representation of arbitrary waveforms and application to the analysis of nonlinear amplifiers and feedforward linearizers
Mutlu, Ahmet; Demir, Şimşek; Department of Electrical and Electronics Engineering (2005)
Characterization of nonlinear systems is a challenging task as the output can not be expressed simply in terms of input signal. Therefore, a universal analysis method is essential to simplify this procedure. Modeling of the input signal is a crucial part of such analysis. In this thesis, multi-tone representation is employed to model arbitrary, stochastically not well-defined input signals and thereafter characterize nonlinear systems. In order to verify the validity of multitone representation, multi-tone ...
Design and construction of reduced size planar spiral antenna in the 0.5-18 ghz frequency range
Yıldız, İnanç; Hızal, Altunkan; Department of Electrical and Electronics Engineering (2004)
In this thesis, theoretical and practical evaluation of usual spiral antenna is revised. Working principles of both types of planar spiral antennas as Equiangular and Archimedean are introduced. A predesigned microstrip tapered balun used for feeding section of a spiral antenna is simulated on Ansoft HFSS software. Successful simulation results are obtained and measurements of implemented balun structure are made by using an HP 8722 D vector network analyzer. Antenna measurement techniques used in this stud...
MMSE based iterative turbo equalization for antenna switching sytems
Yıldırım, Recep Ali; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2010)
In this thesis, we study the performance of an antenna switching (AS) system in comparison to an Alamouti coded system. We analyze the outage probabilities and propose minimum mean-squared error based iterative equalizers for both systems. We see from the outage probability analysis of both systems that the AS system may achieve the same diversity order of the Alamouti coded scheme contingent on the transmission rate and constellation size. In the proposed receiver, MMSE equalization and channel decoding ar...
Citation Formats
U. Öztürk, “Chaotic digital modulation and demodulation,” M.S. - Master of Science, Middle East Technical University, 2005.