Pulse Shape Correlation for Laser Detection and Ranging

<p>An un-biased range estimation algorithm was developed that countered errors caused by pulse shape effects in laser radar (LADAR) systems. The Advanced Scientific Concepts FLASH LADAR created three-dimensional images by measuring return intensity and time of flight for a single laser pulse. A range estimate was made by estimating the return time of flight from the peak amplitude of the return laser pulse. Range error estimates occurred when the shape of the measured return pulse deviated from the expected pulse shape. A normalized variable shaping correlation algorithm called NOVAS performed the correlation between the recorded waveforms and a robust set of Gaussian-based reference waveforms covering a wide range of pulse shapes and asymmetries. While NOVAS did not generate the most accurate range estimates due to noise sensitivity it was able to produce an estimate of the average asymmetric pulse shape. The NOVAS generated average (NGA) asymmetric pulse shape produced a more accurate average range estimate than the NGA symmetric pulse shape in six of seven trials and produced a more accurate average range estimate with less variance than an arbitrarily chosen symmetric reference waveform in all of seven trials.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p>