TITLE:
Application of the Spectrum Peak Positioning Technology Based on BP Neural Network in Demodulation of Cavity Length of EFPI Fiber Optical Sensor
AUTHORS:
Mengran Zhou, Mengya Nie
KEYWORDS:
EFPI Fiber Optical Sensor; The Demodulation of Cavity Length; BP Neural Network; The Peak Positioning Technology
JOURNAL NAME:
Journal of Computer and Communications,
Vol.1 No.7,
December
2,
2013
ABSTRACT: An
Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online
testing system for the gas density. The system achieves the measurement
of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the
demodulation of the cavity length. For shortcomings of the big intensity demodulation
error and complex structure of phase demodulation, this paper proposes that BP neural
net-work is used to locate the special peak points in normalized
interference spectrum and combining the advantages of the unimodal and bimodal measurement
achieves the demodulation of the cavity length. Through online simulation and actual
measurement, the results show that the peak positioning technology based on BP neural
network can not only achieve high-precision demodulation of the cavity length, but
also achieve an absolute measurement of cavity length in large dynamic range.