Sunil Tyagi, PhD

Technical notes

Technical notes

Practical write-ups from the bench — classical sonar techniques, open datasets, and the methods behind current projects. Full text hosted here; also published on LinkedIn.

Signal processing

DEMON Analysis: Reading a Vessel’s Propulsion from Its Own Noise

A working note on a classical technique that still earns its place alongside deep learning — and one way it caught a bug that spectrograms missed.

DEMON analysis: shaft- and blade-rate harmonics extracted from the cavitation envelope of a vessel recording

Read the note · Also on LinkedIn

Open dataset · CC BY 4.0

A Physics-Grounded Synthetic Underwater Acoustic Dataset for Underwater Domain Awareness

Full-factorial waveform generation from first-principle acoustic models — 12,000 physics-grounded clips across four vessel classes and ambient ocean noise, with corrected ambient-noise modelling, physics-based cavitation, and worked verification calculations. Openly released for self-supervised pretraining.

Dataset infographic: full-factorial design factors, non-overlapping shaft-rate ranges, Knudsen sea-noise spectra and example spectrograms

Read the note · GitHub · Also on LinkedIn