Publication Date


Document Type


First Advisor

Bobis, James P.

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Electrical Engineering


Nuclear magnetic resonance spectroscopy; Adaptive filters; Signal processing--Digital techniques


Nuclear magnetic resonance (NMR) spectroscopy is used to determine molecular structure and obtain physicochemical information about molecular dynamics. This technique has been used mainly for laboratory measurements and is often a time-consuming process. Recently, advances in solid-state technology, together with improvements in real-time digital signal processing schemes, have facilitated on-line implementation of NMR technology. NMR spectroscopy is analogous to techniques that measure the transfer function of an electronic device because an NMR signal can be related to the transfer function of a system. In this thesis, a portable NMR controller that is based on the TMS320C30 digital signal processor (C30 DSP) was developed and implemented to measure transfer functions. The controller transmits a radio frequency signal to a sample in a large homogeneous magnetic field, and the resonance absorption of the radio frequency is detected in real time by the C30 DSP. Given the time-domain input signal and prior knowledge of chemical signal patterns, the known signal is separated from a composite signal and enhanced by using an adaptive line enhancer filter scheme. Determination of the chemical and physical properties of composite chemicals would be useful for verifying a material?s processibility and for eventually upgrading industrial processing procedures. The prototype NMR controller system in this work was implemented to detect the chemical structure of a liquid chemical at intervals of 500 ms. The results were verified by comparison with a series of off-line laboratory experiments with a commercial unit.


Includes bibliographical references (pages [57]-58)


viii, 96 pages




Northern Illinois University

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