Modeling of time domain represented signals with multitone signals

Download
index.pdf
2014
Cansız, Gökhan
Show full item record
213
views
99
downloads
Signals in certain systems, such as the transmitted signal in a cellular communication system, are strongly time dependent, non-deterministic and stochastically not well defined. Predicting the performance of the transmitter with such a signal at its input is important for efficient operation. Therefore, it is crucial to model a given time dependent waveform by multi-tone signals, which enables analytical derivations. In this thesis, multi-tone representation is employed to model the varying envelope arbitrary waveforms. Number, amplitude, phase of the tones and spacing between tones are considered as parameters for the multi-tone stimuli. To prove the validity of the multi-tone representation, CCDF curve is considered as a figure of merit for comparison. Different nonlinear amplifiers are excited with an arbitrary waveform and its multi-tone representation in the simulation environment. At the output of the amplifier, similar nonlinear behaviors such as, in-band and out of band distortion powers are observed. After proving that original and model signal have similar nonlinear responses, modulation performance of the arbitrary waveform and model signal in a transmitter chain is investigated for different drive levels.
Signals and signaling., Mobile communication systems., Cell phone systems., Power amplifiers.
http://etd.lib.metu.edu.tr/upload/12617114/index.pdf
https://hdl.handle.net/11511/23526
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Interference suppression capability of faster than symbol rate sampling and frequency domain oversampling
Balevi, Eren; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2016)
Detection of symbols in the presence of many interference sources is a difficult task in wireless channels. It is obligatory to reduce the interference for reliable communication. In this dissertation, minimum mean square error (MMSE) detection is investigated to suppress interference. Faster Than Symbol Rate (FTSR) sampling and Frequency Domain Oversampling (FDO) methods are proposed to enhance the interference suppression level of MMSE detection for both single user and multiuser communication. The aim of...
An alternative multi-tone representation of complex signals for feedforward systems
Coskun, Hakan; Mutlu, Ahmet; Demir, Şimşek (2004-12-01)
Signals used in wireless communication have various stochastic behaviors depending on the type of the modulation. The systems are nonlinear and analysis of these systems with various types of signals is tedious. Therefore developing a universal analysis method and representing any type of input signal with a certain model, such as multi-tone representation and modeling, simplify the analysis and design of these systems enabling initial rapid optimizations and understanding of the system performance. In this...
A bidirectional LMS algorithmfor estimation of fast time-varying channels
Yapıcı, Yavuz; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2011)
Effort to estimate unknown time-varying channels as a part of high-speed mobile communication systems is of interest especially for next-generation wireless systems. The high computational complexity of the optimal Wiener estimator usually makes its use impractical in fast time-varying channels. As a powerful candidate, the adaptive least mean squares (LMS) algorithm offers a computationally efficient solution with its simple first-order weight-vector update equation. However, the performance of the LMS alg...
Improving the efficiency of microwave power amplifiers without linearity degradation using load and bias tuning in a new configuration
Ronaghzadeh, Amin; Demir, Şimşek; Department of Electrical and Electronics Engineering (2013)
Advanced digital modulation schemes used in the wireless applications, result in the modulated RF signals with high peak to average power ratio which requires linear amplification. On the other hand, the demand for a longer talk time with less battery volume and weight, especially in hand-held radio units, necessitate more power efficient methods to be utilized in power amplifier design. But improved linearity and efficiency have always been contradicting requirements demanding innovative power amplifier and...
Evaluation of priority dependent and time scheduled MAC layer protocols for ad-hoc networks
Erdeğer, İsmail; Baykal, Buyurman; Department of Electrical and Electronics Engineering (2015)
Ad-hoc networks have very unique features, such as dynamic topologies, relatively limited bandwidth and wireless signal propagation schemes, which present various challenges for wireless communication. In this thesis, control mechanisms for channel access scheduling and topology in ad-hoc networks are evaluated, which utilize the information from two-hop neighborhood to cope with the communication difficulties in ad-hoc networks. Channel assignment is one of the most important topics for ad-hoc networks. Ch...
Citation Formats
G. Cansız, “Modeling of time domain represented signals with multitone signals,” M.S. - Master of Science, Middle East Technical University, 2014.
METU IIS - Integrated Information Service open@metu.edu.tr