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arXiv · 2603.29355

Recirculating frequency-shifting loop for flexible optical chirp generation and FMCW LiDAR

Alexander Mrokon·Sebastian Schöler·Leonard Vossgrag·Karsten Buse·Ingo Breunig
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Abstract

A recirculating frequency-shifting loop (FSL) provides a highly flexible platform for generating coherent optically chirped light with tunable bandwidth, duration, chirp rate and repetition rate. The properties of the chirped light are controlled using low-frequency sinusoidal electronic drive signals, enabling deterministic waveform synthesis without complex high-speed electronics. We achieve chirp bandwidths of 10 GHz with a duration in the nanosecond regime, representing one of the fastest tunable laser sources to date. Using such chirped laser pulses, we demonstrate coherent FMCW LiDAR measurements over distances up to 3 m, highlighting the potential of FSL-based sources for compact, scalable and high-performance ranging systems.

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Alexander Mrokon, Sebastian Schöler, Leonard Vossgrag, Karsten Buse, Ingo Breunig. 2026-03-31. Recirculating frequency-shifting loop for flexible optical chirp generation and FMCW LiDAR. https://arxiv.org/abs/2603.29355

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