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Coupling Of Audio Signals Into Afm Images, Matthew Manning
Coupling Of Audio Signals Into Afm Images, Matthew Manning
Honors Theses
It is well known that Atomic Force Microscopy imaging is capable of yielding high resolution results with of surfaces at the nanoscale. However, despite the device capabilities and vast applications, AFM microscopy is possibly the most prone to the creation of image artifacts. AFM imaging can easily, and is often, corrupted by various external forces. The most obvious and measurable form of external interference is of course the presence of ambient noise. Most AFM manufactures attempt to counter the effects of such noise on the imaging process through use of noise-proof or noise-resistant shields that cover the microscope aperture. Without …
A Compressive Radar System With Chaos Based Fm Signals Generated Using The Bernoulli Map, Charan Teja Enugula
A Compressive Radar System With Chaos Based Fm Signals Generated Using The Bernoulli Map, Charan Teja Enugula
Electrical Engineering Theses
Matched filters are used in radar systems to identify echo signals embedded in noise. By using matched filters, range and Doppler information about the target can be extracted from the reflected signal. The use of matched filters in high frequency radars has the effect of increasing the cost and complexity of these systems. For that reason, the radar research community is looking at a new technique called compressive sensing or compressive sampling. This technique works by exploiting signal sparsity and has the potential to eliminate the use of matched filters and high frequency analog-to-digital converters. In this research, it is …
Development Of L-Band Down Converter Boards And Real-Time Digital Backend For Phased Array Feeds, Vikas Asthana
Development Of L-Band Down Converter Boards And Real-Time Digital Backend For Phased Array Feeds, Vikas Asthana
Theses and Dissertations
Recent developments in the field of phased array feeds for radio astronomical reflector antennas, have opened a new frontier for array signal processing for radio astronomy observations. The goal is to replace single horn feeds with a phased array feed, so as to enable astronomers to cover more sky area in less time. The development of digital backend signal processing systems has been a major area of concentration for the development of science-ready phased array feeds for radio astronomers. This thesis focuses on the development of analog down-converter receivers and an FPGA-based digital backend for real-time data processing and analysis …
An Inquiry: Effectiveness Of The Complex Empirical Mode Decomposition Method, The Hilbert-Huang Transform, And The Fast-Fourier Transform For Analysis Of Dynamic Objects, Kristen L. Wallis
An Inquiry: Effectiveness Of The Complex Empirical Mode Decomposition Method, The Hilbert-Huang Transform, And The Fast-Fourier Transform For Analysis Of Dynamic Objects, Kristen L. Wallis
Theses and Dissertations
A review of current signal analysis tools show that new techniques are required for an enhanced fidelity or data integrity. Recently, the Hilbert-Huang transform (HHT) and its inherent property, the Empirical Mode Decomposition (EMD) technique, have been formerly investigated. The technique of Complex EMD (CEMD) was also explored. The scope of this work was to assess the CEMD technique as an innovative analysis tool. Subsequent to this, comparisons between applications of the Hilbert transform (HT) and the Fast-Fourier transform (FFT) were analyzed. MATLAB was implemented to model signal decomposition and the execution of mathematical transforms for generating results. The CEMD …
Complex-Valued Adaptive Digital Signal Enhancement For Applications In Wireless Communication Systems, Ying Liu
Electronic Theses and Dissertations
In recent decades, the wireless communication industry has attracted a great deal of research efforts to satisfy rigorous performance requirements and preserve high spectral efficiency. Along with this trend, I/Q modulation is frequently applied in modern wireless communications to develop high performance and high data rate systems. This has necessitated the need for applying efficient complex-valued signal processing techniques to highly-integrated, multi-standard receiver devices. In this dissertation, novel techniques for complex-valued digital signal enhancement are presented and analyzed for various applications in wireless communications. The first technique is a unified block processing approach to generate the complex-valued conjugate gradient Least …