Increasing robustness of bipolar pulse coding in Brillouin distributed fiber sensors

Yang, Zhisheng; Soto, Marcelo A.; Thevenaz, Luc

Abstract

The robustness of bipolar pulse coding against pump depletion issues in Brillouin distributed fiber sensors is theoretically and experimentally investigated. The presented analysis points out that the effectiveness of bipolar coding in Brillouin sensing can be highly affected by the power unbalance between -1's and +1's elements resulting from depletion and amplification of coded pump pulses. In order to increase robustness against those detrimental effects and to alleviate the probe power limitation imposed by pump depletion, a technique using a three-tone probe is proposed. Experimental results demonstrate that this method allows increasing the probe power by more than 12.5 dB when compared to the existing single-probe tone implementation. This huge power increment, together with the 13.5 dB signal-to-noise enhancement provided by 512-bit bipolar Golay codes, has led to low-uncertainty measurements (0.9 MHz) of the local Brillouin peak gain frequency over a real remoteness of 100 km, using a 200 km-long fiber-loop and 2 m spatial resolution. The method is evaluated with a record figure-of-merit of 380'000. (C) 2016 Optical Society of America

Más información

Título según WOS: ID WOS:000368004800058 Not found in local WOS DB
Título de la Revista: OPTICS EXPRESS
Volumen: 24
Número: 1
Editorial: OPTICAL SOC AMER
Fecha de publicación: 2016
Página de inicio: 586
Página final: 597
DOI:

10.1364/OE.24.000586

Notas: ISI