A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique...A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique based on Simplex codes and Golay codes and time division multiplexing technique to enhance the performance of the sensing system.Simulation results,in good agreement with the theory,confirmed that the maximum SNR enhancement of the sensor system employing composite coding based on 15-bit Simplex codes and 16-bit Golay codes was approximately 6.01 dB in comparison to the conventional single pulse case.展开更多
The detection of multiple acoustic disturbances by optical fiber is a hot research topic in the field of optical fiber sensing.This paper considers adopting an optical distributed acoustic sensing(DAS)system to detect...The detection of multiple acoustic disturbances by optical fiber is a hot research topic in the field of optical fiber sensing.This paper considers adopting an optical distributed acoustic sensing(DAS)system to detect multiple acoustic disturbances,proposes a new approach to processing the DAS signal based on time-space average in frequency domain,and overcomes the randomness of DAS time domain signal.Finally,it obtains a functional model of single-frequency(50-1000 Hz)sound pressure level and DAS signal intensity,and also the cut-off frequency of acoustic disturbance is detected by DAS system.展开更多
基金Graduate Project Foundation of Shanghai Polytechnic University,China(No.A01GY18F022)
文摘A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique based on Simplex codes and Golay codes and time division multiplexing technique to enhance the performance of the sensing system.Simulation results,in good agreement with the theory,confirmed that the maximum SNR enhancement of the sensor system employing composite coding based on 15-bit Simplex codes and 16-bit Golay codes was approximately 6.01 dB in comparison to the conventional single pulse case.
基金the Graduate Program Foundation of Shanghai Polytechnic University(No.EGD18YJ0045)。
文摘The detection of multiple acoustic disturbances by optical fiber is a hot research topic in the field of optical fiber sensing.This paper considers adopting an optical distributed acoustic sensing(DAS)system to detect multiple acoustic disturbances,proposes a new approach to processing the DAS signal based on time-space average in frequency domain,and overcomes the randomness of DAS time domain signal.Finally,it obtains a functional model of single-frequency(50-1000 Hz)sound pressure level and DAS signal intensity,and also the cut-off frequency of acoustic disturbance is detected by DAS system.
