All-optical coherent pulse compression for dynamic laser ranging using an acousto-optic dual comb

Vincent Billault (1) , Vicente Durán (2) , Carlos R Fernández-Pousa (3) , Vincent Crozatier (1) , Daniel Dolfi (4) , Hugues Guillet de Chatellus (5)

1 Thales Research and Technology [Palaiseau]
2 INIT - Institut de Noves Tecnologies de la Imatge
3 UMH - Universidad Miguel Hernández [Elche]
4 Thales Research and Technology - Thales Research and Technology
5 LIPhy - Laboratoire Interdisciplinaire de Physique [Saint Martin d’Hères]

We demonstrate a new and simple dynamic laser ranging platform based on analog all-optical coherent pulse compression of modulated optical waveforms. The technique employs a bidirectional acousto-optic frequency shifting loop, which provides a dual-comb photonic signal with an optical bandwidth in the microwave range. This architecture simply involves a CW laser, standard telecom components and low frequency electronics, both for the dual-comb generation and for the detection. As a laser ranging system, it offers a range resolution of a few millimeters, set by a dual-comb spectral bandwidth of 24 GHz, and a precision of 20 µm for an integration time of 20 ms. The system is also shown to provide dynamic measurements at scanning rates in the acoustic range, including phase-sensitive measurements and Doppler shift velocimetry. In addition, we show that the application of perfect correlation phase sequences to the transmitted waveforms allows the ambiguity range to be extended by a factor of 10 up to ∼20 m. The system generates quasi-continuous waveforms with low peak power, which makes it possible to envision long-range telemetry or reflectometry requiring highly amplified signals.

Domaines: Sciences de l'ingénieur [physics]

Vincent Billault, Vicente Durán, Carlos R Fernández-Pousa, Vincent Crozatier, Daniel Dolfi, et al.. All-optical coherent pulse compression for dynamic laser ranging using an acousto-optic dual comb. Optics Express, 2021, 29, ⟨10.1364/oe.430998⟩. ⟨hal-03441638⟩