Date of Award
Doctor of Philosophy (PhD)
Department of Engineering Physics
Glen P. Perram, PhD
The depth of absorption bands in observed spectra of distant, bright sources can be used to estimate range to the source. A novel approach is presented and demonstrated using observations of the oxygen absorption band near 762 nm. Range is estimated by comparing observed values of band-average absorption against curves derived from either historical data or model predictions. Curves are based on fitting a random band model to the data, which reduces average range error by 67% compared to the Beer's Law model used in previous work. A new modification to existing band models for long, inhomogeneous paths is presented and shown to reduce error 50% in short-range experiments. A static rocket motor test was observed using a Fourier transform spectrometer at a range of 2.8 km. The range estimated from this data was accurate to within 0.5% (14 m). Similar accuracy was also achieved at shorter ranges using a lamp as a surrogate target. Long-range performance is predicted by using FASCODE and theoretical models to extrapolate observed short-range performance. Range error of 5% or less is predicted at ranges up to 400 km for a representative target.
DTIC Accession Number
Hawks, Michael R., "Passive Ranging Using Atmospheric Oxygen Absorption Spectra" (2006). Theses and Dissertations. 3339.