Date of Award
9-25-2008
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Department of Electrical and Computer Engineering
First Advisor
Michael A. Temple, PhD
Abstract
A design process is demonstrated for a coexistent scenario containing Spectrally Modulated, Spectrally Encoded (SMSE) and Direct Sequence Spread Spectrum (DSSS) signals. Coexistent SMSE-DSSS designs are addressed under both perfect and imperfect DSSS code tracking conditions using a non-coherent delay-lock loop (DLL). Under both conditions, the number of SMSE subcarriers and subcarrier spacing are the optimization variables of interest. For perfect DLL code tracking conditions, the GA and RSM optimization processes are considered independently with the objective function being end-to-end DSSS bit error rate. A hybrid GA-RSM optimization process is used under more realistic imperfect DLL code tracking conditions. In this case, optimization is accomplished using a correlation degradation metric with the GA process being first applied to generate a “coarse” solution followed by RSM processing which provides the final optimized solution. This work has successfully expanded the practical utility of a previously developed tool, the original SMSE framework, by demonstrating a more efficient, structured means for coexistent waveform design that replaces previous trial and error methods.
AFIT Designator
AFIT-DEE-ENG-08-16
DTIC Accession Number
ADA487275
Recommended Citation
Beard, Todd W., "Application of Optimization Techniques to Spectrally Modulated, Spectrally Encoded Waveform Design" (2008). Theses and Dissertations. 2524.
https://scholar.afit.edu/etd/2524