BOTDA
Brillouin interaction+time-domain analysis+distributed strain / temperature
TECHNOLOGY STARTS HERE
The Fiber Sensing Atlas
A five-layer framework for understanding how distributed fiber sensing, Rayleigh, Raman, Brillouin, FBG, OTDR, OFDR, DAS, DTS, and DSS fit together.
The names are many. The architecture is not.
Follow the photon
ONE SYSTEM, FIVE DECISIONS
Read any fiber sensing term by asking the same five questions.
Start with the engineering problem, not the acronym. The same optical effect can be read in different ways, and one interrogation architecture can recover more than one physical quantity.
- 01Where to sense?
- 02What optical effect to use
- 03How to interrogate it
- 04What physical quantity to recover?
- 05Where to apply the result
INTERACTIVE TECHNOLOGY MAP
Explore compatible technology combinations.
Select a system example below. Multiple stations may illuminate within the same layer because these relationships are many-to-many, not exclusive one-to-one mappings.
One valid system recipe: a dense quasi-distributed UW-FBG array can combine time-domain positioning and coherent phase detection to recover both dynamic strain and acoustic information for many application families.
How to read the map: choose an example above, or click any station below to reveal its common compatible routes. The branching light bundles show choice and combination; they do not imply that every highlighted item must be used at once.
Learn how Rayleigh, Raman, Brillouin and Bragg reflection differ →
Sensing Topology
Where to sense?
Topology describes how measurement locations are arranged along the fiber. It does not specify the optical effect or the interrogation method.
Optical Interaction
What optical effect to use
This is the physical layer: natural scattering, an artificial grating reflection, or an interferometric response.
Interrogation & Localization
How to interrogate it
OTDR and OFDR belong here. They are interrogation and spatial-mapping architectures, not optical scattering mechanisms.
Measured Quantity
What physical quantity to recover?
DAS, DTS and DSS are named primarily by the measurand. The same quantity can often be recovered through different physical and interrogation routes.
Engineering Application
Where to apply the result
The application is the final layer. Bridge monitoring and pipeline integrity are not sensing mechanisms; they combine suitable routes from the four layers above.
DECODE THE NAME
Some terms describe one layer. Others combine several.
This is why OTDR, Brillouin, BOTDA, and DAS should not be treated as equivalent categories.
φ-OTDR DAS
coherent Rayleigh scattering+phase-sensitive OTDR+acoustic / vibration
Raman DTS
Raman scattering+time-of-flight localization+temperature
UW-FBG uwDAS
ultra-weak reflection array+coherent time-domain demodulation+acoustic / micro-vibration
WHERE UW-FBG FITS
UW-FBG is a sensing foundation, not a synonym for OTDR, OFDR, DAS, or DTS.
An ultra-weak grating array defines controlled reflection points and a high-density quasi-distributed topology. Different interrogation methods can then recover strain, temperature, acoustic, vibration, or other transduced quantities.
- Topology
- High-density quasi-distributed array
- Interaction
- Artificial ultra-weak Bragg reflection
- Interrogation
- Time, wavelength, phase, frequency, or hybrid
- Measurands
- Strain, temperature, acoustic, vibration
CONTINUE THE JOURNEY