Today, it is commonly agreed that mid-range rangefinders (typical range: 10 km) based on fiber laser
technology, constitute the best trade-off between performance and reliability. But to intend to compete with
long-range devices and propose an alternative to bulk solid state laser systems, it is essential to increase
significantly their extinction ratio (ER) compared to the state of the art.
In this paper, we report on successive real-time statistical algorithms performed on 2 different fiber laser
rangefinders and the feasability to achieve an extinction ratio up to 45dB in an eye-safety burst mode. Based
on a bi-static architecture and equipped with a 38 μJ and 125 μJ, 10 ns pulse fiber laser, their intrinsic ER in
single-pulse emission has been measured respectively at 28 and 33 dB. A 45 mm optical aperture receiver
and a specially designed compact electronics complete the device. This alternative to solid-states systems
dedicated to long range application, represents then a cost-effective solution.
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