Analog to digital converter for UWB short range indoor radar system
Abstract
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In this project the analog-to-digital converter is designed for an ultra-wideband short-range radar (UWBSRR) health-event monitoring system. The input signal frequency range for the ADC is 3.2GHz to 4.7GHz. To meet the accuracy and detection requirements of the system, it was derived that a resolution of 4-bits and a sampling speed of 10GHz per second was required. After a survey on various available high speed ADC architectures and research on power, speed, accuracy, design complexity, cost and area tradeoff between the architecture a decision was made that a combination of 2-bit folding and 2-bit flash converter with 5-stages of time interleaved operation with each individual stage sampling at 2GHz can give a sampling rate of 10GHZ. However, considering the difficulty in designing a folding converter which can operate at input frequencies of 3.2GHz to 4.7GHz, a new architecture with a modification to the traditional flash architecture is proposed. Using this architecture, when operated at a sampling speed of 2GHz and used as a sub-converter of a five stage time-interleaved converter, a sampling speed of 10GHz can be achieved. A sample and hold circuit forms an important part in the design and one is designed here in this thesis was to work at a sampling speed of 2GHz, an input frequencies of 3.2 to 4.7GHz and an input range of 0.5V to 1.0V. The maximum amplitude error in the sampled value was found to be 23.2mv. The aperture time for a change in input from 0.5V to 1.0V was found to be 25.7 pico seconds.
Degree
M.S.
Thesis Department
Rights
Access is limited to the campuses of the University of Missouri.