Vibration Sensor Based on Hollow Biconical Fiber

A hollow biconical fiber is proposed and experimentally demonstrated for vibration sensing. It is fabricated by creating an air micro-cavity in single-mode fiber, followed by tapering it. Experimental results show that the device is highly sensitive to bending with a sensitivity of 21.30 dB/m−1. When it is exposed to vibration, its transmission loss is modulated periodically, then based on the measured transmission, the vibration frequency can be demodulated accurately. The acoustic vibration testing results show that the proposed device can detect and demodulate the exciting acoustic frequency accurately and distinguish its sound intensity, and the maximum signal to noise ratio (SNR) achieves up to 59 dB. Moreover, cantilever beam testing proves its performance reliable. Additionally, the sensing head has the advantages of a lightweight, compact size (with a total length of less than 250 μm), and insensitivity of temperature. All these features indicate the proposed sensor has a promising potential in the engineering field.

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Sensitive acoustic vibration sensor using single-mode fiber tapers

Applied Optics ◽

10.1364/ao.50.001873 ◽

2011 ◽

Vol 50 (13) ◽

pp. 1873 ◽

Cited By ~ 36

Author(s):

Yi Li ◽

Xiaozhen Wang ◽

Xiaoyi Bao

Keyword(s):

Single Mode ◽

Acoustic Vibration ◽

Single Mode Fiber ◽

Vibration Sensor

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Microdrilled tapers to enhance optical fiber lasers for sensing

Scientific Reports ◽

10.1038/s41598-021-00046-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

R. A. Perez-Herrera ◽

M. Bravo ◽

P. Roldan-Varona ◽

D. Leandro ◽

L. Rodriguez-Cobo ◽

...

Keyword(s):

Optical Fiber ◽

Optical Fibers ◽

Fiber Lasers ◽

Signal To Noise Ratio ◽

Power Level ◽

Single Mode ◽

Optical Signal ◽

Single Mode Fiber ◽

Output Power Level ◽

Linear Cavity

AbstractIn this work, an experimental analysis of the performance of different types of quasi-randomly distributed reflectors inscribed into a single-mode fiber as a sensing mirror is presented. These artificially-controlled backscattering fiber reflectors are used in short linear cavity fiber lasers. In particular, laser emission and sensor application features are analyzed when employing optical tapered fibers, micro-drilled optical fibers and 50 μm-waist or 100 μm-waist micro-drilled tapered fibers (MDTF). Single-wavelength laser with an output power level of about 8.2 dBm and an optical signal-to-noise ratio of 45 dB were measured when employing a 50 μm-waist micro-drilled tapered optical fiber. The achieved temperature sensitivities were similar to those of FBGs; however, the strain sensitivity improved more than one order of magnitude in comparison with FBG sensors, attaining slope sensitivities as good as 18.1 pm/με when using a 50 μm-waist MDTF as distributed reflector.

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Fabrication, Characterization and Microsensing of Whispering-Gallery Mode Micro-Coupling Systems

Volume 13: Nano-Manufacturing Technology; and Micro and Nano Systems, Parts A and B ◽

10.1115/imece2008-66946 ◽

2008 ◽

Cited By ~ 1

Author(s):

Qiulin Ma ◽

Tobias Rossmann ◽

Zhixiong Guo

Keyword(s):

Transmission Loss ◽

Coupling Efficiency ◽

High Sensitivity ◽

Single Mode ◽

Whispering Gallery Mode ◽

Single Mode Fiber ◽

Whispering Gallery ◽

Coupling System ◽

Wide Range ◽

Micro Sensor

An optical micro-coupling system of whispering-gallery mode usually consists of a resonator (e.g. a sphere) and a coupler (e.g. a taper). In this report, silica microspheres of 50–500 μm in diameter are fabricated by hydrogen flame fusing of an end of a single mode fiber or fiber taper. Fiber tapers are fabricated by the method of heating and pulling that meets an adiabatic condition. Taper’s waist diameter can routinely be made less than 1 μm and almost zero transmission loss in a taper is achieved which allows an effective and phase-matched coupling for a wide range sizes of microspheres. Both resonators and couplers’ surface microstructure and shapes are examined by scanning electronic microscopy. Three regimes of coupling are achieved, enabling a good flexibility to control Q value and coupling efficiency of a micro-coupling system. Whispering gallery mode shift is used to demonstrate a novel temperature micro-sensor. Its sensitivity determined from actual experimental results agrees well with the theoretical value. A concept of using the photon’s cavity ring down (CRD) in the microsphere to make a novel high-sensitivity trace gas micro-sensor is proposed. The CRD time constant when ammonia is chosen as the analyte gas is predicted using the simulated absorption lines.

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Improvement of signal-to-noise ratio of a subterahertz spectrometer using a continuous-wave multimode laser diode by single-mode fiber optics

Applied Physics Letters ◽

10.1063/1.1777800 ◽

2004 ◽

Vol 85 (6) ◽

pp. 881-883 ◽

Cited By ~ 16

Author(s):

O. Morikawa ◽

M. Fujita ◽

M. Hangyo

Keyword(s):

Fiber Optics ◽

Laser Diode ◽

Continuous Wave ◽

Signal To Noise Ratio ◽

Single Mode ◽

Single Mode Fiber ◽

Signal To Noise ◽

Multimode Laser ◽

Noise Ratio ◽

Multimode Laser Diode

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Efficient Blind Adaptive CSE to Reduce Cyclic Prefix Length in Direct Detection Optical OFDM Systems

Journal of Optical Communications ◽

10.1515/joc-2018-0165 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

Asmaa Benieddi ◽

Sid Ahmed Elahmar

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Direct Detection ◽

Group Velocity Dispersion ◽

Signal To Noise Ratio ◽

Single Mode ◽

Optical Signal ◽

Single Mode Fiber ◽

Cyclic Prefix ◽

Ofdm Systems ◽

Blind Adaptive

AbstractDirect detection optical orthogonal frequency division multiplexing (DDO-OFDM) systems for a long-reach of standard single mode fiber (SSMF) require a large length of cyclic prefix (CP) to avoid the inter-symbol interference (ISI) effect caused by group velocity dispersion (GVD). Unfortunately, this method is inefficient due to the energy wasted in CP samples. In order to reduce the CP length and to mitigate the residual ISI, a novel blind adaptive channel shortening equalizer (CSE) is proposed in this paper. Based on the orthogonality between subcarriers in the fast Fourier transform (FFT) property, the proposed algorithm attempts to minimize the sum-squared correlation (SSCM) between each sample located in a well-defined window to update the CSE coefficients. Thus, the combined channel-CSE response is shortened. Therefore, it can cancel the residual ISI effect due to the GVD and the short CP length. The performance of the system is evaluated on basis of bit error rate (BER) versus optical signal to noise ratio (OSNR) for different CP lengths. The simulation results validate the new algorithm SSCM and show that it can reduce the CP length with a much better system improvement than existing algorithms.

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Single-Mode Fiber-Optic Vibration Sensor

10.1117/12.949778 ◽

1986 ◽

Cited By ~ 7

Author(s):

E. Udd ◽

P. A. Turek

Keyword(s):

Fiber Optic ◽

Single Mode ◽

Single Mode Fiber ◽

Vibration Sensor

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Carrier-Assisted Phase Retrieval

10.36227/techrxiv.17170814 ◽

2021 ◽

Author(s):

Qi Wu

Keyword(s):

Phase Retrieval ◽

Forward Error Correction ◽

Signal To Noise Ratio ◽

Single Mode ◽

Local Oscillator ◽

Optical Signal ◽

Single Mode Fiber ◽

Critical Parameters ◽

Hardware Complexity ◽

Full Field

Phase-retrieval (PR) schemes based on the modified Gerchberg-Saxton (GS) algorithm capture the full-field employing a dispersive element and intensity-only measurements to eliminate the use of a local oscillator. In this work, we propose two carrier-assisted PR schemes, namely central carrier-assisted PR (CCA-PR) and edge carrier-assisted PR (ECA-PR), to improve the comprehensive performance of PR receiver in terms of convergence speed, redundancy, and computational complexity. The proposed CCA-PR recovers the electrical field employing a reference carrier at 0 GHz with several iterations between two projection planes. It avoids pilot symbols and digital backpropagation to the transmitter and offers a flexible electrical bandwidth requirement compared with conventional PR schemes. To lower the carrier-to-signal power ratio (CSPR) requirement and enable faster convergence for the carrier-assisted PR schemes, the ECA-PR is proposed to obtain the initial phase for the GS algorithm. We numerically characterize the performance of the two schemes and experimentally demonstrate them for 30 GBaud 16-quadrature amplitude modulation (16-QAM) transmission over 80 km single-mode fiber with a bit error rate (BER) below the threshold of 7% hard-decision forward error correction (HD-FEC). Several critical parameters are analyzed, including the applied dispersion value, CSPR, and electrical bandwidth. Moreover, we compare the hardware complexity and optical signal-to-noise ratio (OSNR) sensitivity of proposed PR schemes with mainstream field recovery schemes.

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Analysis of secured Optical Orthogonal Frequency Division Multiplexed System

Journal of Optical Communications ◽

10.1515/joc-2016-0075 ◽

2017 ◽

Vol 38 (2) ◽

Cited By ~ 1

Author(s):

Harsimranjit Singh Gill ◽

Kamaljit Singh Bhatia ◽

Sandeep Singh Gill

Keyword(s):

Signal To Noise Ratio ◽

Average Power ◽

Single Mode ◽

Optical Signal ◽

Data Encryption ◽

Single Mode Fiber ◽

Frequency Division ◽

Ofdm Systems ◽

Ofdm Signal ◽

Coded Ofdm

AbstractIn this paper, security issues for optical orthogonal frequency division multiplexed (OFDM) systems are emphasized. The encryption has been done on the data of coded OFDM symbols using data encryption standard (DES) algorithm before transmitting through the fiber. The results obtained justify that the DES provides better security to the input data without further bandwidth requirement. The data is transmitted to a distance of 1,000 km in a single-mode fiber with 16-quadrature amplitude modulation. The peak-to-average power ratio and optical signal-to-noise ratio of secure coded OFDM signal is fairly better than the conventional OFDM signal.

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Miniature on-fiber extrinsic Fabry-Perot interferometric vibration sensors based on micro-cantilever beam

Nanotechnology Reviews ◽

10.1515/ntrev-2019-0028 ◽

2019 ◽

Vol 8 (1) ◽

pp. 293-298 ◽

Cited By ~ 1

Author(s):

Weiyi Ma ◽

Yi Jiang ◽

Han Zhang ◽

Liuchao Zhang ◽

Jie Hu ◽

...

Keyword(s):

Cantilever Beam ◽

Single Mode ◽

Single Mode Fiber ◽

Vibration Sensor ◽

Fiber Axis ◽

Vibration Sensors ◽

Beam Design ◽

Cantilever Length ◽

Fabry Perot ◽

Micro Cantilever

Abstract An on-fiber extrinsic Fabry–Perot interferometric (EFPI) vibration sensor based on micro-cantilever beam is proposed and experimentally demonstrated. The micro-cantilever beam, with a cantilever length of 80μm and a cantilever thickness of 5μm, is created perpendicular to the fiber axis by using the femtosecond laser micro-machining technique. The on-fiber vibration sensor has same diameter with that of the single mode fiber. An acceleration sensitivity of 11.1 mV/g@300 Hz in the range of 0.5-5g is demonstrated experimentally. This on-fiber and micro-cantilever beam design allows for the sensor to be smaller size and higher temperature resistance.

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