Laser radar tomography-the effects of speckle

Recent experiments have used tomographic techniques to reconstruct images of rotating targets from either range-resolved or Doppler-resolved laser radar data. In the range-time-intensity (RTI) imaging approach, a series of N range projections of the target reflectivity is collected throughout the target rotation period by direct detection of a short-duration laser illumination pulse. In the companion Dopplertime-intensity imaging (DTI) technique, a set of N Doppler-resolved target reflectivity projections is recorded over the target rotation by an optical heterodyne laser radar receiver. The resulting two-dimensional image formed from either set of N projections is corrupted by detector shot-noise and optical speckle effects. This thesis theoretically models and analyzes the statistical performance of both RTI and DTI imaging systems. Performance predictions are made in terms of radartarget geometry, electromagnetic propagation, target characteristics, coherent or incoherent detection, post-detection processing and tomographic image reconstruction. The derived image signal-to-noise ratios (SNR's) and point spread functions (PSF's) are used to compare the two approaches to existing experimental data. Thesis Supervisor: Professor Jeffrey H. Shapiro Title: Professor of Electrical Engineering