Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Analog-to-digital converters (1)
- Biometric identification; Hidden Markov models; Pattern recognition systems; Signal processing--Digital techniques (1)
- Cognitive radio networks; Digital communications; Electronics; Orthogonal frequency division multiplexing; Wireless communication systems (1)
- Delta-sigma modulators (1)
- Global optimization (1)
Articles 1 - 3 of 3
Full-Text Articles in Engineering
Human Identification Using Pyroelectric Infrared Sensors, Aron E. Suppes
Human Identification Using Pyroelectric Infrared Sensors, Aron E. Suppes
UNLV Theses, Dissertations, Professional Papers, and Capstones
The objective of this thesis is to discuss the viability of using pyroelectric infrared (PIR) sensors as a biometric system for human identification.
The human body emits infrared radiation, the distribution of which varies throughout the body, and depends upon the shape and composition of the particular body part. A PIR sensor utilizing a Fresnel lens will respond to this infrared radiation. When a human walks, the motion of the body's individual components form a characteristic gait that is likely to affect a PIR sensor field in a unique way.
A statistical model, such as a Hidden Markov Model, could …
Low Power Fft Processor Design Considerations For Ofdm Communications, David Layne Rushforth
Low Power Fft Processor Design Considerations For Ofdm Communications, David Layne Rushforth
UNLV Theses, Dissertations, Professional Papers, and Capstones
Today's emerging communication technologies require fast processing as well as efficient use of resources. This project specifically addresses the power-efficient design of an FFT processor as it relates to OFDM communications such as cognitive radio. The Fast Fourier Transform (FFT) processor is what enables the efficient modulation in OFDM. As the FFT processor is the most computationally intensive component in OFDM communication, the power efficiency improvement of this component can have great impacts on the overall system. These impacts are significant considering the number of mobile and remote communication devices that rely on limited battery-powered operation. This project explores current …
Optimal Design Of Discrete-Time Delta Sigma Modulators, Matthew Edward Jackson
Optimal Design Of Discrete-Time Delta Sigma Modulators, Matthew Edward Jackson
UNLV Theses, Dissertations, Professional Papers, and Capstones
In this thesis, optimal signal transfer functions (STFs) and noise transfer functions (NTFs) for discrete time delta sigma (ΔΣ) modulators are determined. For a given oversampling rate (OSR), these STFs and NTFs are optimized with respect to a weighted combination of the ΔΣ modulator's signal-to-noise ratio (SNR) and dynamic range (DR). This optimization problem is solved using a novel hybrid orthogonal genetic (HOG) algorithm that uses customized genetic operators to improve algorithm performance and accuracy when applied to multimodal, non-differentiable performance surfaces. To generate optimal system functions, the HOG algorithm is implemented as a constrained global optimizer to minimize cost …