We propose a compensation technique based on pulse reference for intensity-modulated optical fiber sensors that can compensate the power fluctuation of the light source, the change of optical components transmission l...We propose a compensation technique based on pulse reference for intensity-modulated optical fiber sensors that can compensate the power fluctuation of the light source, the change of optical components transmission loss, and the coupler splitting ratio. The theoretical principle of this compensation technique is analyzed and a temperature sensor based on fiber coating-covered optical microfiber is carried out to demonstrate the compensation effect. The system noise is measured to be 0.0005 dB with the temperature sensitivity reaching -0.063 dB/℃, and the output drift is 0.006 dB in 2 h at room temperature. The output shows a slight variation （0.0061 dB） when the light source and the common liKht path suffer a 3 dB attenuation fluctuation.展开更多
We propose a simple algorithm for the precise engineering of multi-channel gain profile of Raman amplifier. By employing a linear approximation in the pump interaction calculation, together with a semi-empirical pump ...We propose a simple algorithm for the precise engineering of multi-channel gain profile of Raman amplifier. By employing a linear approximation in the pump interaction calculation, together with a semi-empirical pump power correction using the simplistic output signal spectrum measurement, excellent gain engineering capability has been demonstrated for various target gain profiles, within +/- 0.4dB of error.展开更多
We modify the pulse-reference-based compensation technique and propose a low-noise and highly stable optical fiber temperature sensor based on a zinc telluride film-coated fiber tip. The system noise is measured to be...We modify the pulse-reference-based compensation technique and propose a low-noise and highly stable optical fiber temperature sensor based on a zinc telluride film-coated fiber tip. The system noise is measured to be 0.0005 dB, which makes it possible for the detection of the minor reflectivity change of the film at different temperatures. The temperature sensitivity is 0.0034 d B/℃, so the resolution can achieve 0.2℃. The maximum difference of the temperature output values of the sensor at 20℃ at different points in time is 0.39℃. The low cost, ultra-small size, high stability, and good repeatability of the sensor make it a promising temperature sensing device for practical application.展开更多
This paper proposes a 12-bit,40-Ms/s pipelined analog-to-digital converter（ADC） with an improved high-gain and wide-bandwidth operational amplifier（opamp）.Based on the architecture of the proposed ADC,the non-idea...This paper proposes a 12-bit,40-Ms/s pipelined analog-to-digital converter（ADC） with an improved high-gain and wide-bandwidth operational amplifier（opamp）.Based on the architecture of the proposed ADC,the non-ideal factors of opamps are first analyzed,which have the significant impact on the ADC＇s resolution.Then,the compensation techniques of the ADC＇s opamp are presented to restrain the negative effect introduced by the gainboosting technique and switched-capacitor common-mode-feedback structure.After analysis and optimization,the ADC implemented in a 0.35μm standard CMOS process shows a maximum signal-to-noise distortion ratio of 60.5 dB and a spurious-free dynamic range of 74.5 dB,respectively,at a 40 MHz sample clock with over 2 Vpp input range.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61505258 and 11574397)the Scientific Research Project of the National University of Defense Technology(No.JC15-11-02)
文摘We propose a compensation technique based on pulse reference for intensity-modulated optical fiber sensors that can compensate the power fluctuation of the light source, the change of optical components transmission loss, and the coupler splitting ratio. The theoretical principle of this compensation technique is analyzed and a temperature sensor based on fiber coating-covered optical microfiber is carried out to demonstrate the compensation effect. The system noise is measured to be 0.0005 dB with the temperature sensitivity reaching -0.063 dB/℃, and the output drift is 0.006 dB in 2 h at room temperature. The output shows a slight variation （0.0061 dB） when the light source and the common liKht path suffer a 3 dB attenuation fluctuation.
文摘We propose a simple algorithm for the precise engineering of multi-channel gain profile of Raman amplifier. By employing a linear approximation in the pump interaction calculation, together with a semi-empirical pump power correction using the simplistic output signal spectrum measurement, excellent gain engineering capability has been demonstrated for various target gain profiles, within +/- 0.4dB of error.
基金supported by the National Natural Science Foundation of China(Nos.11574397,61775238,61705262,and 61705263)the Scientific Research Project of National University of Defense Technology(No.JC15-11-02)
文摘We modify the pulse-reference-based compensation technique and propose a low-noise and highly stable optical fiber temperature sensor based on a zinc telluride film-coated fiber tip. The system noise is measured to be 0.0005 dB, which makes it possible for the detection of the minor reflectivity change of the film at different temperatures. The temperature sensitivity is 0.0034 d B/℃, so the resolution can achieve 0.2℃. The maximum difference of the temperature output values of the sensor at 20℃ at different points in time is 0.39℃. The low cost, ultra-small size, high stability, and good repeatability of the sensor make it a promising temperature sensing device for practical application.
基金Project supported by the National Natural Science Foundation of China(No.61106025)
文摘This paper proposes a 12-bit,40-Ms/s pipelined analog-to-digital converter（ADC） with an improved high-gain and wide-bandwidth operational amplifier（opamp）.Based on the architecture of the proposed ADC,the non-ideal factors of opamps are first analyzed,which have the significant impact on the ADC＇s resolution.Then,the compensation techniques of the ADC＇s opamp are presented to restrain the negative effect introduced by the gainboosting technique and switched-capacitor common-mode-feedback structure.After analysis and optimization,the ADC implemented in a 0.35μm standard CMOS process shows a maximum signal-to-noise distortion ratio of 60.5 dB and a spurious-free dynamic range of 74.5 dB,respectively,at a 40 MHz sample clock with over 2 Vpp input range.
