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Proceedings Paper • Open Access

MIT/LL development of broadband linear frequency chirp for high-resolution ladar
Author(s): Kevin W. Holman; David G. Kocher; Sumanth Kaushik

Paper Abstract

The development of a high-resolution laser radar (ladar) exhibiting sub-mm resolution would have a great impact on standoff identification applications. It would provide biometric identification capabilities such as three-dimensional facial recognition, interrogation of skin pore patterns and skin texture, and iris recognition. The most significant technical challenge to developing such a ladar is to produce the appropriate optical waveform with high fideltiy. One implementation of such a system requires a 1.5-THz linear frequency sweep in 75 &mgr;s. Previous demonstrations of imaging with such waveforms achieved a 1 THz sweep in > 100 ms, and required additional corrections to compensate for sweep nonlinearity. The generation of high fidelity, temporally short frequency-swept waveforms is of considerable interest to the DoD community. We are developing a technique that utilizes a novel method to generate a 1 THz sweep in 50 &mgr;s from a mode-locked laser. As a proof-of-principle demonstration of this technique we have successfully generated a 20 GHz sweep in 1 µs with a fidelity sufficient to produce better than -20 dB sidelobes for a range measurement without using any additional corrections. This method is scalable to produce the entire 1 THz sweep in 50 &mgr;s.

Paper Details

Date Published: 16 May 2007
PDF: 8 pages
Proc. SPIE 6572, Enabling Photonics Technologies for Defense, Security, and Aerospace Applications III, 65720J (16 May 2007); doi: 10.1117/12.724272
Show Author Affiliations
Kevin W. Holman, MIT Lincoln Lab. (United States)
David G. Kocher, MIT Lincoln Lab. (United States)
Sumanth Kaushik, MIT Lincoln Lab. (United States)

Published in SPIE Proceedings Vol. 6572:
Enabling Photonics Technologies for Defense, Security, and Aerospace Applications III
Michael J. Hayduk; Andrew R. Pirich; Peter J. Delfyett Jr.; Eric J. Donkor; John P. Barrios; Rebecca J. Bussjager; Michael L. Fanto; Robert L. Kaminski; Guifang Li; Hooman Mohseni; Edward W. Taylor, Editor(s)

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