Distributed optical fiber sensing technology, compared to traditional electrical sensing technology, offers inherent advantages such as intrinsic safety, no sparking, and corrosion resistance. As a new generation of sensing technology, it is now being applied across various industries. As professionals working with distributed optical fiber sensing technology, how can we build our own DAS system? This document compiles some basic concepts and points beginners should be aware of to avoid common pitfalls.

Basic Theoretical Knowledge

As a new technology, distributed optical fiber sensing is also a complex interdisciplinary field integrating optics, electronics, and computation. Therefore, before attempting to build a good DAS system, we need to grasp some fundamental theoretical knowledge.

It is essential to thoroughly read literature and technical documents in the early stages to understand the implementation of DAS systems. A common schematic diagram for DAS systems found on the market is shown below.

From the schematic above, we can see that the core components required for a DAS system include: a Laser, Acousto-Optic Modulator (AOM), EDFA, Balanced Photodetector (BPD), and a Data Acquisition Card.

What Do You Want to Do Yourself?

 

·         I want to set up this entire system.

·         I'm studying optoelectronics; I want to develop the laser driver, EDFA, and balanced photodetector.

·         I work with FPGAs; I want to develop the demodulation and acquisition algorithms for the DAS.

·         I need to understand the principles of this system thoroughly, set it up, and develop some applications myself.

 

Everyone might have a different answer.

A Distributed Acoustic Sensing (DAS) system is a complex system involving multiple functional components. For researchers in optoelectronics or precision instrumentation, it is possible to selectively develop the functionality of specific parts of the system. However, it is not recommended to attempt building all components from scratch, as this involves challenges not only at the technical level but also regarding time investment. Therefore, it is advised to focus on self-developing some core components based on your specialization and expertise.

 

Testing is Easier with a Reference

 

When developing your own DAS components, it is best to have a test setup available for rapid testing. Having a reference makes testing easier. Otherwise, it's difficult to compare performance and determine if your developed components meet the requirements.

Preparing a test setup involves selecting specialized DAS hardware module manufacturers. This is because these DAS devices and equipment have been validated and tested before leaving the factory. If you source component modules from different suppliers independently, it is likely that the system will either not function properly or not perform optimally.

As an experienced provider of optical fiber sensing solutions, we can offer you complete DAS device modules. For clients pursuing self-development, we also provide Bill of Materials (BOM) solutions for individual components. These component solutions have been validated and are capable of delivering excellent signal quality.