Opportunistic Sampling by Level-Crossing

level-crossing;sampling;bursty;consistent signal reconstruction;data compression;finite rate of innovation;universal sequential;Analog-to-Digital Converters (ADCs)

Guan, Karen

关键词: level-crossing;    sampling;    bursty;    consistent signal reconstruction;    data compression;    finite rate of innovation;    universal sequential;    Analog-to-Digital Converters (ADCs);   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/30884/Guan_Karen.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This dissertation addresses an alternative sampling method called level-crossing (LC). In recent years LChas emerged as an alternative to the traditional Nyquist-Shannon based sampling. While the conventionalapproach is an ideal enabler of reliable and perfect signal reconstruction, it is not always economical andefficient. LC is a threshold-based sampling that is particularly suitable for processing bursty signals, whichexist in a diverse range of settings.The motivations for this work are twofold: one is to address signal reconstruction outside of the conventionalparadigm, and the other is to address compression in data processing. This work makes the followingcontributions: 1. consistent reconstruction algorithm via LC for a general class of signals, 2. perfect reconstructionalgorithm via LC for signals of finite rate of innovation, 3. a universal sequential algorithm forthe placement of reference levels that is competitive with the best static scheme known a priori, and 4. anumerical index that measures signal sparseness which is used to analytically show the relationship betweenrate of transmission and signal characteristics.The framework established in this work aims to capture the full potential of LC. Insights gained from theanalytical work will contribute to the establishment of new data acquisition protocols and provide referencesfor hardware implementations of LC ADCs.ii