RT Journal Article
T1 Simultaneous Multifrequency Demodulation for Single-Shot Multiple-Path ToF Imaging
A1 Shahandashti, Peyman Fayyaz
A1 López Martínez, Paula
A1 Brea Sánchez, Víctor Manuel
A1 García Lesta, Daniel
A1 Heredia Conde, Miguel
K1 Sensors
K1 Demodulation
K1 Imaging
K1 Frequency modulation
K1 Image sensors
K1 Lighting
K1 Computer architecture
AB Indirect Time-of-Flight (iToF) sensors measure the received signal's phase shift or time delay to calculate depth. In realistic conditions, however, recovering depth is challenging as reflections from secondary scattering areas or translucent objects may interfere with the direct reflection, resulting in inaccurate 3D estimates. We propose a new measurement concept including a single-shot on-chip multifrequency demodulation method with periodically-repeated ultrashort-pulsed illumination using a novel pixel array architecture to address a main limitation of conventional iToF, the Multi-Path Interference (MPI). Due to the careful hardware/software codesign, the proposed single-shot architecture provides close-to-optimal Fourier measurements to a spectral estimation algorithm that retrieves the unknown parameters of the interfering return paths in a closed form. Electrical simulations of the on-chip multifrequency demodulation circuit demonstrate the feasibility of distance retrieval in double and triple bounce conditions in a single shot with high accuracy. Furthermore, we propose a set of methods for processing the resulting sensor measurements that exploit valuable a priori information and structural constraints of the data and observe that they yield a substantial increase in accuracy
PB IEEE
SN 2573-0436
YR 2024
FD 2024
LK http://hdl.handle.net/10347/33246
UL http://hdl.handle.net/10347/33246
LA eng
NO P. F. Shahandashti, P. López, V. M. Brea, D. García-Lesta and M. H. Conde, "Simultaneous Multifrequency Demodulation for Single-Shot Multiple-Path ToF Imaging," in IEEE Transactions on Computational Imaging, vol. 10, pp. 54-68, 2024, doi: 10.1109/TCI.2023.3348758. keywords: {Sensors;Demodulation;Imaging;Frequency modulation;Image sensors;Lighting;Computer architecture;CMOS image sensor;depth image sensor;macro-pixel;multifrequency demodulation;multipath interference;single-shot;spectral estimation;time-of-flight}
DS Minerva
RD 24 abr 2026