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Description
Machine learning (ML) has played an important role in several modern technological innovations and has become an important tool for researchers in various fields of interest. Besides engineering, ML techniques have started to spread across various departments of study, like health-care, medicine, diagnostics, social science, finance, economics etc. These techniques

Machine learning (ML) has played an important role in several modern technological innovations and has become an important tool for researchers in various fields of interest. Besides engineering, ML techniques have started to spread across various departments of study, like health-care, medicine, diagnostics, social science, finance, economics etc. These techniques require data to train the algorithms and model a complex system and make predictions based on that model. Due to development of sophisticated sensors it has become easier to collect large volumes of data which is used to make necessary hypotheses using ML. The promising results obtained using ML have opened up new opportunities of research across various departments and this dissertation is a manifestation of it. Here, some unique studies have been presented, from which valuable inference have been drawn for a real-world complex system. Each study has its own unique sets of motivation and relevance to the real world. An ensemble of signal processing (SP) and ML techniques have been explored in each study. This dissertation provides the detailed systematic approach and discusses the results achieved in each study. Valuable inferences drawn from each study play a vital role in areas of science and technology, and it is worth further investigation. This dissertation also provides a set of useful SP and ML tools for researchers in various fields of interest.
ContributorsDutta, Arindam (Author) / Bliss, Daniel W (Thesis advisor) / Berisha, Visar (Committee member) / Richmond, Christ (Committee member) / Corman, Steven (Committee member) / Arizona State University (Publisher)
Created2018
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Description
As the demand for wireless systems increases exponentially, it has become necessary

for different wireless modalities, like radar and communication systems, to share the

available bandwidth. One approach to realize coexistence successfully is for each

system to adopt a transmit waveform with a unique nonlinear time-varying phase

function. At the receiver of the system

As the demand for wireless systems increases exponentially, it has become necessary

for different wireless modalities, like radar and communication systems, to share the

available bandwidth. One approach to realize coexistence successfully is for each

system to adopt a transmit waveform with a unique nonlinear time-varying phase

function. At the receiver of the system of interest, the waveform received for process-

ing may still suffer from low signal-to-interference-plus-noise ratio (SINR) due to the

presence of the waveforms that are matched to the other coexisting systems. This

thesis uses a time-frequency based approach to increase the SINR of a system by estimating the unique nonlinear instantaneous frequency (IF) of the waveform matched

to the system. Specifically, the IF is estimated using the synchrosqueezing transform,

a highly localized time-frequency representation that also enables reconstruction of

individual waveform components. As the IF estimate is biased, modified versions of

the transform are investigated to obtain estimators that are both unbiased and also

matched to the unique nonlinear phase function of a given waveform. Simulations

using transmit waveforms of coexisting wireless systems are provided to demonstrate

the performance of the proposed approach using both biased and unbiased IF estimators.
ContributorsGattani, Vineet Sunil (Author) / Papandreou-Suppappola, Antonia (Thesis advisor) / Richmond, Christ (Committee member) / Maurer, Alexander (Committee member) / Arizona State University (Publisher)
Created2018