Reference-beam storage for long-range low-coherence pulsed Doppler lidar.
We present a laser Doppler velocimeter that stores and delays the reference beam to preserve coherence with a long-path-length measurement beam. Our storage and delay technique relaxes the strict coherence requirements associated with lidar laser sources, permitting the use of low-coherence lasers. This technique potentially could reduce the cost and size of lidar systems for commercial applications. Experiments that use fiber-optic ring resonators to store the reference beams and generate reference pulse trains validated the concept. We obtained results at several simulated distances by beating each usable reference pulse with a delayed Doppler-shifted measurement beam reflected off a rotating mirror.
Dorrington
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Kunnemeyer
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Danehy
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