An effective method for the improvement of the characteristics of an erbium-doped L-band superfluorescent fiber source(SFS)is demonstrated using an unpumped erbium-doped fiber(EDF).With a suitable length of unpumped E...An effective method for the improvement of the characteristics of an erbium-doped L-band superfluorescent fiber source(SFS)is demonstrated using an unpumped erbium-doped fiber(EDF).With a suitable length of unpumped EDF section in the single-forward pumped configuration,broadening of the L-band spectral linewidth is achieved and the variation of mean wavelength versus pump power is eliminated.A mean wavelength stable L-band SFS with a spectral linewidth of 50.2 nm and an output power of 60.2 mW is obtained experimentally.The method of using unpumped EDF enables one to offer a stable and wideband L-band SFS with high flexibility and to overcome the shortcomings of the synchronous pumping technique.展开更多
In this paper, we present a method based on self-mixing interferometry combing extreme learning machine for real-time human blood pressure measurement. A signal processing method based on wavelet transform is applied ...In this paper, we present a method based on self-mixing interferometry combing extreme learning machine for real-time human blood pressure measurement. A signal processing method based on wavelet transform is applied to extract reversion point in the self-mixing interference signal, thus the pulse wave profile is successfully reconstructed. Considering the blood pressure values are intrinsically related to characteristic parameters of the pulse wave, 80 samples from the MIMIC-II database are used to train the extreme learning machine blood pressure model. In the experiment, 15 measured samples of pulse wave signal are used as the prediction sets. The results show that the errors of systolic and diastolic blood pressure are both within 5 mm Hg compared with that by the Coriolis method.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61108019the Fujian Provincial Natural Science Foundation of China under Grant No 2011J01368.
文摘An effective method for the improvement of the characteristics of an erbium-doped L-band superfluorescent fiber source(SFS)is demonstrated using an unpumped erbium-doped fiber(EDF).With a suitable length of unpumped EDF section in the single-forward pumped configuration,broadening of the L-band spectral linewidth is achieved and the variation of mean wavelength versus pump power is eliminated.A mean wavelength stable L-band SFS with a spectral linewidth of 50.2 nm and an output power of 60.2 mW is obtained experimentally.The method of using unpumped EDF enables one to offer a stable and wideband L-band SFS with high flexibility and to overcome the shortcomings of the synchronous pumping technique.
基金supported by the National Natural Science Foundation of China (No.61675174)the Natural Science Foundation of Fujian Province (No.2020J01705)。
文摘In this paper, we present a method based on self-mixing interferometry combing extreme learning machine for real-time human blood pressure measurement. A signal processing method based on wavelet transform is applied to extract reversion point in the self-mixing interference signal, thus the pulse wave profile is successfully reconstructed. Considering the blood pressure values are intrinsically related to characteristic parameters of the pulse wave, 80 samples from the MIMIC-II database are used to train the extreme learning machine blood pressure model. In the experiment, 15 measured samples of pulse wave signal are used as the prediction sets. The results show that the errors of systolic and diastolic blood pressure are both within 5 mm Hg compared with that by the Coriolis method.
