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Amplitude-Modulated Continuous-Wave Time-of-Flight (AMCW-ToF) Depth L1-095

Depth ImagingIndirect ToF via phaseδ=3 · standardL_DAG = 3.2📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

A NIR source is amplitude-modulated at frequency f_mod (10-100 MHz). Light reflected from the scene picks up a round-trip phase shift phi = 4*pi*f_mod*d/c. Four-bucket demodulation at the pixel extracts in-phase and quadrature components, from which phi and amplitude are computed. Depth d = c * phi / (4*pi*f_mod), with wrap ambiguity c/(2*f_mod). Multi-frequency captures resolve wraps.

L-DAG

L.modulate.amcw -> L.reflect_scene -> L.demodulate -> int.temporal
L.modulate.amcwL.reflect_sceneL.demodulateint.temporal

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
700

Well-posed with multi-frequency unwrap (3 f_mod sufficient for Chinese Remainder Theorem unwrap). Precision sigma_d ~ c / (4*pi*f_mod * sqrt(SNR)). Multipath interference (MPI) at concave corners and translucent surfaces biases depth; motion during 4-bucket integration causes phase artifacts.

Solvability C

Solver class:
four-bucket quadrature + CRT unwrap, MPI correction (sparse deconvolution, SRA, learned), deep ToF (ToF-DeepNet, ToF-FlowNet)
Convergence rate q:
2
Complexity:
O(H * W * K) for bucket demod; O(H * W * N_freq) for multi-freq unwrap

Specs (0)

No L2 specs registered yet for this principle.