| Summary: | Thesis (M.S.) University of Alaska Fairbanks, 2007 The Kodiak SuperDARN (Super Dual Auroral Radar Network), located on Kodiak Island, Alaska, is a coherent-backscatter radar sensitive to Bragg scatter from ionospheric irregularities. SuperDARN transmitters send out a sequence of seven pulses that aid in the formation of complex autocorrelation functions (ACFs). These ACFs allow for estimating the power, velocity and the spectral widths of the scattering plasma waves. However, the multipulse sequence used currently has some characteristics that are not ideal for the intended purpose. In addition, the analysis technique for estimating the properties of the ACF assumes that there is only a single velocity component present in each range cell at one time. In this study, the aperiodic radar technique designed by Dr. John D. Sahr and Dr. Sathyadev. V. Uppala was investigated to design an optimized transmission sequence that would have no repeated lags, a minimum number of inherently missing lags and no loss of lags due to Tx-on/Rx-off conflicts. With the designed transmission sequence, efficient analysis of data is possible through the use of a standard spectral estimator, the modified covariance technique. The design enhances the ability of the radar to discriminate targets in the same range bin. 1. Introduction -- 2. An introduction to radar principles -- 3. Introduction to the Kodiak SuperDARN -- 4. Aperiodic pulse sequences and their applicability to SuperDARN -- 5. Pulse sequence design -- 6. Implementation and analysis -- 7. Summary, conclusions, and future work -- Bibliography -- Appendix.
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