Hybrid aperiodic coding for SNR improvement in a BOTDA fiber sensor

The measurement accuracy of a Brillouin optical time domain analysis (BOTDA) fiber sensor is determined by the signal-to-noise ratio (SNR) of the received sensing signal. Here, a new hybrid aperiodic coding method is proposed to improve the SNR. In the proposed method, two pre-discovered short seed aperiodic codes (SA-codes) are used to construct a new hybrid aperiodic code (HA-code) in a nested way. The HA-code inherits the good denoising capabilities of the two SA-codes and features a high coding gain. In the proof-of-concept experiment, a SNR improvement up to 8 dB is obtained, which improves the measurement certainty to 1.67 MHz over a 117.46 km sensing range under a spatial resolution of 2.6 m. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

The new hybrid aperiodic coding method improves the measurement accuracy of BOTDA fiber sensors by increasing the SNR by up to 8 dB, achieving a measurement certainty of 1.67 MHz over a 117.46 km sensing range with a spatial resolution of 2.6 m in a proof-of-concept experiment.