A dual-frequency distributed Bragg reflector （DBR） fiber laser based sensor is demonstrated for low-frequency vibration measurement through the Doppler effect. The response of the proposed sensor is quite linear and...A dual-frequency distributed Bragg reflector （DBR） fiber laser based sensor is demonstrated for low-frequency vibration measurement through the Doppler effect. The response of the proposed sensor is quite linear and is much higher than that of a conventional accelerometer. The proposed sensor can work down to 1 Hz with high sensitivity. Therefore, the proposed sensor is very efficient in low-frequency vibration measurement.展开更多
Auto-regressive （AR） spectral estimation technology is proposed to analyze the Brillouin scattering spectrum in Brillouin optical time-domain refelectometry. It shows that AR based method can reliably estimate the B...Auto-regressive （AR） spectral estimation technology is proposed to analyze the Brillouin scattering spectrum in Brillouin optical time-domain refelectometry. It shows that AR based method can reliably estimate the Brillouin frequency shift with an accuracy much better than fast Fourier transform （FFT） based methods provided the data length is not too short. It enables about 3 times improvement over FFT at a moderate spatial resolution.展开更多
A compact fiber-optic magnetic field sensor is proposed by packaging an orthogonal dual-frequency fiber grating laser and a copper wire with alternating electrical current together inside epoxy resin.The alternating c...A compact fiber-optic magnetic field sensor is proposed by packaging an orthogonal dual-frequency fiber grating laser and a copper wire with alternating electrical current together inside epoxy resin.The alternating current generates Ampere force in a magnetic field,which changes the birefringence of the fiber laser and hence tunes the frequency of the beat signal after photodetection.The magnetic flux density can then be detected by measuring the frequency change of the beat signal.The sensitivity of the sensor can be tuned with a maximum response of 35.21 kHz/kGs demonstrated.Moreover,the sensor shows good immunity to environment interference.展开更多
We demonstrate a compact and high-resolution dual-polarization fiber laser accelerometer. A spring-mass like scheme is constructed by fixing a 10-gram proof mass on the laser cavity to transduce applied vibration into...We demonstrate a compact and high-resolution dual-polarization fiber laser accelerometer. A spring-mass like scheme is constructed by fixing a 10-gram proof mass on the laser cavity to transduce applied vibration into beat-frequency change. The loading is located at the intensity maximum of intracavity light to maximize the optical response. The detection limit reaches 107 ng/Hz1/2 at 200 Hz. The working bandwidth ranges from 60 Hz to 600 Hz.展开更多
基金Acknowledgment This work was supported by the National Natural Science Foundation of China （Grant Nos. 11474133 and 61235005）, Natural Science Foundation of Guangdong Province of China （No. 2014A030310419）, and the Guangzhou Key Collaborative Innovation Foundation of China （No.
文摘A dual-frequency distributed Bragg reflector （DBR） fiber laser based sensor is demonstrated for low-frequency vibration measurement through the Doppler effect. The response of the proposed sensor is quite linear and is much higher than that of a conventional accelerometer. The proposed sensor can work down to 1 Hz with high sensitivity. Therefore, the proposed sensor is very efficient in low-frequency vibration measurement.
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. 11474133 and 61235005） and Science and Technology Program of Guangzhou （No. 201707010338）.
文摘Auto-regressive （AR） spectral estimation technology is proposed to analyze the Brillouin scattering spectrum in Brillouin optical time-domain refelectometry. It shows that AR based method can reliably estimate the Brillouin frequency shift with an accuracy much better than fast Fourier transform （FFT） based methods provided the data length is not too short. It enables about 3 times improvement over FFT at a moderate spatial resolution.
基金supported in part by the National Natural Science Foundation of China(NSFC)(Grant Nos.61875246 and 61675091)the Science and Technology Plan of Guangzhou(Grant No.201707010338).
文摘A compact fiber-optic magnetic field sensor is proposed by packaging an orthogonal dual-frequency fiber grating laser and a copper wire with alternating electrical current together inside epoxy resin.The alternating current generates Ampere force in a magnetic field,which changes the birefringence of the fiber laser and hence tunes the frequency of the beat signal after photodetection.The magnetic flux density can then be detected by measuring the frequency change of the beat signal.The sensitivity of the sensor can be tuned with a maximum response of 35.21 kHz/kGs demonstrated.Moreover,the sensor shows good immunity to environment interference.
基金This work is supported by the National Natural Science Foundation of China （Nos. 61235005 and 11474133）, Guangdong Natural Science Foundation （No. $2013030013302）, and the Planned Science ＆ Technology Project of Guangzhou （Nos. 2012J510028 and 2014J2200003）. L. Jin is supported by the Department of Education, Guangdong Province （No. Yq2013021） and by Open Fund of the Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques （South China University of Technology）.
文摘We demonstrate a compact and high-resolution dual-polarization fiber laser accelerometer. A spring-mass like scheme is constructed by fixing a 10-gram proof mass on the laser cavity to transduce applied vibration into beat-frequency change. The loading is located at the intensity maximum of intracavity light to maximize the optical response. The detection limit reaches 107 ng/Hz1/2 at 200 Hz. The working bandwidth ranges from 60 Hz to 600 Hz.
