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Application of a logarithmic analog to digital converter to video processing
Title
Application of a logarithmic analog to digital converter to video processing.
Creator
Glatt, Terry Laurence., Florida Atlantic University, Glenn, William E.
Abstract/Description
Recent advances in integrated circuit technology have resulted in the manufacture of analog to digital converters with a logarithmic transfer characteristic that can operate at video rates. This thesis shows that applying this sort of non-linearity to video signals during digitizing will result in a system that will more closely match the human visual system. The appropriate background is presented including image reproduction, psychophysical aspects of perception, quantization error, and...
Show moreRecent advances in integrated circuit technology have resulted in the manufacture of analog to digital converters with a logarithmic transfer characteristic that can operate at video rates. This thesis shows that applying this sort of non-linearity to video signals during digitizing will result in a system that will more closely match the human visual system. The appropriate background is presented including image reproduction, psychophysical aspects of perception, quantization error, and contrast sensitivity. The background is then related to logarithmic processing with respect to minimizing contouring and improving the fidelity of detail in saturated colors. Finally, logarithmic processing was simulated using an image processor and prototype logarithmic analog to digital converters. The results of this demonstration are presented.
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Date Issued
1991
PURL
http://purl.flvc.org/fcla/dt/14691
Subject Headings
Analog-to-digital converters, Image transmission
Format
Document (PDF)
software-hardware implementation of a real-time digital signal processing receiver for noise detection using a broadband microwave correlation technique
Title
A software-hardware implementation of a real-time digital signal processing receiver for noise detection using a broadband microwave correlation technique.
Creator
Christodoulou, Christodoulos A., Florida Atlantic University, Helmken, Henry
Abstract/Description
In this research project the objective is to realize a software - hardware design implementation of a real time digital signal processing (DSP) radiometer - receiver for atmospheric noise temperature detection using the digital cross correlation technique. Atmospheric noise in the band of 20-30 GHz band is down-converted to 10.7 MHz IF and 3 MHz bandwidth in the form of statistical additive white gaussian noise which is used as the received signal by a digital signal processing broadband...
Show moreIn this research project the objective is to realize a software - hardware design implementation of a real time digital signal processing (DSP) radiometer - receiver for atmospheric noise temperature detection using the digital cross correlation technique. Atmospheric noise in the band of 20-30 GHz band is down-converted to 10.7 MHz IF and 3 MHz bandwidth in the form of statistical additive white gaussian noise which is used as the received signal by a digital signal processing broadband microwave radiometer based on the digital cross correlation technique. Living in a technological era, which is characterized as the era of data transmission and reception for RF-wireless communication systems, the theory of RF digital signal processing detection has applied to radar, ultrasound, and digital communications. Due to the need of high speed of data detection, much effort has gone into the design and development of sophisticated equipment to obtain such DSP detectors. Detection can also apply in seismic and big earthquake measurements by using geophones, nuclear testing, sonar and acoustic localizations, and even for oil excavations. Based on a statistical model and proposed design implementation, a basic DSP atmospheric noise temperature radiometer system is introduced and developed. The realization of the DSP Radiometer examines the noise characteristics (parameters) and their corresponding parameter values at the received input at the Antenna. It is essential to introduce the fundamental and statistical properties of the additive white gaussian noise, as well as the key-parameters which are used for the development of this real time design implementation. A design implementation of the proposed DSP atmospheric noise radiometer is discussed and developed via a statistical analysis. The statistical analysis utilizes the standard deviation, intermediate frequency, bandwidth, number of samples, and the temperature of the noise received signal at the antenna. Measurements and real time simulations in order to evaluate the noise temperature’s detectability in terms of system’s accuracy and performance of the noise random variable are also presented in this research work. The advantage of the digital cross correlation technique is examined and investigated.
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Date Issued
2005
PURL
http://purl.flvc.org/fcla/dt/13290
Subject Headings
Signal processing--Digital techniques, Analog-to-digital converters, Radio--Receivers and reception
Format
Document (PDF)