Time domain spectral LiDAR enabled by cascaded Raman in a hydrogen-filled fiber transmitter

We introduce what we believe to be novel spectral light detection and ranging (LiDAR) architectures that enable ultra-compact systems by a transition from spectral signal processing in space (gratings) to processing in time. The architectures leverage temporal dispersion and the unique spectro-temporal waveforms produced from the cascaded Raman scattering generated in the (H 2 ) filled hollow core fiber. The characterized Raman source yields as many as six Raman orders from 1.06-1.70 μ m; their unique spectro-temporal waveforms are measured. System performance simulations based on measured Raman waveforms show that high accuracy measurement of range and reflectivity are possible with proper selection of signal-to-noise ratio and detector bandwidth. Materials classification analysis based on the system performance analysis shows that near-optimal classification is feasible with time domain processing.