Signal error correction and target positioning method based on distributed acoustic sensing

Distributed Acoustic Sensing (DAS) uses fiber-optic cables to detect underwater sounds by analyzing light pulses, offering advantages like high resolution and large coverage. However, errors in signal measurements—caused by temperature changes, manufacturing differences, or interference between sensors—reduce accuracy in locating targets. This study introduces a method to correct these errors (amplitude, phase, and mutual coupling) in real time without physical access to the sensors. By combining advanced mathematical techniques and iterative algorithms, the system simultaneously estimates errors and identifies the direction of underwater sound sources. Field tests in a deep lake and computer simulations showed the method improvement on localization accuracy. For example, after correction, the system achieved a 5.37 dB gain in signal clarity and reduced errors in arrival angle estimation. This approach provides a practical solution for enhancing DAS performance in underwater monitoring, such as detecting ships or securing pipelines, even in challenging environments.