A high-resolution fiber optic accelerometer based on intracavity phase-generated carrier (PGC) modulation

Abstract

A compact-size fiber optic accelerometer was designed to achieve both high resolution and wide dynamic range concurrently. An optical cavity, with its length modulated by a piezoelectric oscillator at audio frequency, is utilized to resolve the nanometer-level displacement of a silicon micro-mirror which serves as an inertial mass for acceleration sensing. Strain analysis of the proof-mass flexure structure by Cosmosworks was carried out to calculate responsivity and resonance frequency for a comparison with experimental measurement. The responsivity below the structural resonance frequency of 160 Hz reaches 36 dB re 1 rad/g. Performance measurement demonstrated that the accelerometer was able to resolve an acceleration of 48 ng Hz−1/2 with a dynamic range of 2 × 107.

Short cavity DFB fiber laser based vector hydrophone for low frequency signal detection

“…Then a commercial OPD4000 (optical phase demodulation) is applied together with the PGC (phase generation carrier) algorithm to restore the wavelength change [12].…”

Design of vibration sensor based on fiber Bragg grating

“…From the strain sensor model of the FBG, it can be seen that if the strain of the FBG is a periodic dynamic strain that changes over time and the change is due to the vibration of the object connected to it, then the model can be used to measure the period sexual vibration (such as simple harmonic vibration) [8,9]. For a deterministic vibration, the main parameters are: acceleration, amplitude, velocity, and vibration frequency.…”

Research Progress of Fiber Grating Vibration Sensor

“…Commonly used fiber interferometers generally include Michelson interferometer (MSI), Mach-Zehnder interferometer (MZI) and Fabry-Perot interferometer (FPI). Therefore, this paper will review the optical phase modulation type vibration sensor from the fiber MSI vibration sensor [13][14][15][16][17], the optical fiber MZI vibration sensor [18][19] and the optical fiber FPI vibration sensor [20][21][22][23][24][25].…”

“…According to the composition of the reflecting surface, the optical fiber FPI can be divided into two types, one is the FPI [21] formed by the surface of the vibration target as the second reflecting surface; the other is the FPI composed of the dual fiber end face, the optical fiber FPI of this type The sensor is generally designed to fix external vibrations by measuring the deformation or stress of the mechanical vibration response structure by fixing the FPI to some mechanical vibration response structures [22][23][24]. Such mechanical vibration response structures mainly include cantilever beams [23 ] Rectangular plate, elastic rope [22], diaphragm [25] and so on. In 1998, Norbert et al [20] designed a sensor based on a mass-spring system with a reflector on the end of the mass, which formed an enamel cavity on the end of the fiber.…”

“…In recent years, fiber optic sensor technology based on fiber optic sensor with its anti-electromagnetic interference, small size, light weight, wide dynamic range, high precision, can work in harsh environments have been the rapid development of the advantages [2]. In the past few decades, fiber optic vibration sensor has been a lot of research and reports, according to the parameters of light modulation can be divided into four categories: light intensity modulation [3][4][5][6][7][8][9][10][11][12], optical phase modulation [13][14][15][16][17][18][19][20][21][22][23][24][25] And optical wavelength modulation [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] vibration sensor, this paper mainly discusses the status of these three sensors.…”