This paper presents a 12-channel,30Gb/s front-end amplifier realized in standard 0.18μm CMOS technology for parallel optlc-fiber receivers. In order to overcome the problem of inadequate bandwidth caused by the large...This paper presents a 12-channel,30Gb/s front-end amplifier realized in standard 0.18μm CMOS technology for parallel optlc-fiber receivers. In order to overcome the problem of inadequate bandwidth caused by the large parasitical capacitor of CMOS photo-detectors,a regulated-cascode structure and noise optimization are used in the design of the transimpedance amplifier. The experimental results indicate that, with a parasitical capacitance of 2pF,a single channel is able to work at bite rates of up to 2.5Gb/s,and a clear eye diagram is obtained with a 0. 8mVpp input. Furthermore, an isolation structure combined with a p^＋ guard.ring （PGR）, an n^＋ guard-ring （NGR）,and a deep-n-well （DNW） for parallel amplifier is also presented. Taking this combined structure, the crosstalk and the substrate noise coupling have been effectively reduced. Compared with the isolation of PGR or PGR ＋ NGR,the measured results show that the isolation degree of this structure is improved by 29.2 and 8. ldB at 1GHz,and by 8. 1 and 2. 5dB at 2GHz,respectively. With a 1.8V supply,each channel of the front-end amplifier consumes a DC power of 85mW,and the total power consumption of 12 channels is about 1W.展开更多
A rapid analysis method of piperazine ferulate tablets by optic-fiber sensing technology with UV-vis absorption spectrum was established. Qualitative and quantitative data were obtained and compared by maximum and min...A rapid analysis method of piperazine ferulate tablets by optic-fiber sensing technology with UV-vis absorption spectrum was established. Qualitative and quantitative data were obtained and compared by maximum and minimum wavelength, absorbance and contrast spectra. Similarity method was used to identify authenticity of drugs. The difference of contents measured by this method and UV determination method in China Pharmacopoeia showed no statistical significance (P40.05), while the similarity can be used as a parameter to identify the authenticity of drugs.展开更多
The micromechanical behaviors and mechanics-optics coupling effects of optic-fiber-concrete complex in the distributed optic-fiber sensing concrete-crack technology,which was used in health monitoring of Wu Gorge Brid...The micromechanical behaviors and mechanics-optics coupling effects of optic-fiber-concrete complex in the distributed optic-fiber sensing concrete-crack technology,which was used in health monitoring of Wu Gorge Bridge on Yangtze River and a large dam successfully,have been investigated.A micromechanical theoretical analysis method and micromechanical frictional contact bi-interface model,as well as a modified optical theoretical analysis method of the mechanics-optics coupling effects are presented.A series of verification experiments,including mechanical experiments and mechanics-optics coupling experiments,have been preformed.The results of micromechanical theoretical analysis and the analysis of the modified theory of mechanics-optics coupling along with mechanical and optical experimental data are shown to be in close agreement.Both the micromechanical theory and the modified theory of mechanics-optics coupling with their analysis methods can not only enhance credibility of this novel distributed sensing technology but also provide a way to understand its sensing mechanism and optimize its technical details and system.展开更多
The behavior of a single mode optic-fiber interferometric hydrophone with ring resonator is discribed in this paper. The optic-fiber ring resonant hydrophone has rery high optical finesse, and receiving sensitivity le...The behavior of a single mode optic-fiber interferometric hydrophone with ring resonator is discribed in this paper. The optic-fiber ring resonant hydrophone has rery high optical finesse, and receiving sensitivity level about -130 dB (re 1 V/μPa).展开更多
We make an experimental study on vibration frequency response of micro-bend optic-fiber sensor, and single-mode fibers and multi-mode fibers are used as the sensitive optic-fibers. Contrast between the two sensitive f...We make an experimental study on vibration frequency response of micro-bend optic-fiber sensor, and single-mode fibers and multi-mode fibers are used as the sensitive optic-fibers. Contrast between the two sensitive fibers is presented. Result shows that the micro-bend optic-fiber sensor has good frequency response characteristics and strong ability to restore the waveform. With the frequency varying in the range of 500 - 4762 Hz, the vibration sensors using multi-mode optic-fiber as the sensitive fiber is more sensitive than that using single-mode optic-fiber. And the former has better frequency response characteristics and stronger capacity of waveform revivification. But with the frequency in the range of 287 - 500 Hz, the latter is better.展开更多
变压器热点温度作为运行经济性、安全性的关键指标,是设备在线监测及状态评估中的重点。该文对变压器内部散热进行研究,着眼于饼式绕组及其油道结构,基于能量流向建立绕组温度变化的物理模型。基于这一模型,在一台内置分布式传感光纤的1...变压器热点温度作为运行经济性、安全性的关键指标,是设备在线监测及状态评估中的重点。该文对变压器内部散热进行研究,着眼于饼式绕组及其油道结构,基于能量流向建立绕组温度变化的物理模型。基于这一模型,在一台内置分布式传感光纤的110kV三相ONAN变压器上开展试验研究,使用分布式光纤测温(distributed temperature sensing,DTS)技术对运行状况下的绕组整体温度分布进行实时监测,分析绕组在ONAN冷却方式下的散热状况。在变压器启动初期,绕组各处散热量较低,温升速率较快。约2 h后,各饼散热量基本与损耗相一致,散热率可达98%以上,因此将这一阶段称为准稳态。准稳态阶段,绕组整体散热率基本一致。负载变化前期不同位置散热量的差异是温度梯度形成的主要原因。基于DTS手段及散热器进出口处油温,提出绕组每饼平均对流换热系数的计算方法,基于无量纲数建立绕组内外表面局部对流换热系数的计算方法,对不同位置、负载率下两种对流换热系数的变化规律进行分析获得了绕组运行过程中对流换热系数分布规律及变化趋势。展开更多
文摘This paper presents a 12-channel,30Gb/s front-end amplifier realized in standard 0.18μm CMOS technology for parallel optlc-fiber receivers. In order to overcome the problem of inadequate bandwidth caused by the large parasitical capacitor of CMOS photo-detectors,a regulated-cascode structure and noise optimization are used in the design of the transimpedance amplifier. The experimental results indicate that, with a parasitical capacitance of 2pF,a single channel is able to work at bite rates of up to 2.5Gb/s,and a clear eye diagram is obtained with a 0. 8mVpp input. Furthermore, an isolation structure combined with a p^＋ guard.ring （PGR）, an n^＋ guard-ring （NGR）,and a deep-n-well （DNW） for parallel amplifier is also presented. Taking this combined structure, the crosstalk and the substrate noise coupling have been effectively reduced. Compared with the isolation of PGR or PGR ＋ NGR,the measured results show that the isolation degree of this structure is improved by 29.2 and 8. ldB at 1GHz,and by 8. 1 and 2. 5dB at 2GHz,respectively. With a 1.8V supply,each channel of the front-end amplifier consumes a DC power of 85mW,and the total power consumption of 12 channels is about 1W.
文摘A rapid analysis method of piperazine ferulate tablets by optic-fiber sensing technology with UV-vis absorption spectrum was established. Qualitative and quantitative data were obtained and compared by maximum and minimum wavelength, absorbance and contrast spectra. Similarity method was used to identify authenticity of drugs. The difference of contents measured by this method and UV determination method in China Pharmacopoeia showed no statistical significance (P40.05), while the similarity can be used as a parameter to identify the authenticity of drugs.
基金supported by the National Natural Science Foundation of China and the Joint Foundation of Yalong River Hydropower Development (Grant No.50579094)
文摘The micromechanical behaviors and mechanics-optics coupling effects of optic-fiber-concrete complex in the distributed optic-fiber sensing concrete-crack technology,which was used in health monitoring of Wu Gorge Bridge on Yangtze River and a large dam successfully,have been investigated.A micromechanical theoretical analysis method and micromechanical frictional contact bi-interface model,as well as a modified optical theoretical analysis method of the mechanics-optics coupling effects are presented.A series of verification experiments,including mechanical experiments and mechanics-optics coupling experiments,have been preformed.The results of micromechanical theoretical analysis and the analysis of the modified theory of mechanics-optics coupling along with mechanical and optical experimental data are shown to be in close agreement.Both the micromechanical theory and the modified theory of mechanics-optics coupling with their analysis methods can not only enhance credibility of this novel distributed sensing technology but also provide a way to understand its sensing mechanism and optimize its technical details and system.
文摘The behavior of a single mode optic-fiber interferometric hydrophone with ring resonator is discribed in this paper. The optic-fiber ring resonant hydrophone has rery high optical finesse, and receiving sensitivity level about -130 dB (re 1 V/μPa).
基金supported by the Fifth 100 Innovative Activities Projects of Nankai University (No. 94)
文摘We make an experimental study on vibration frequency response of micro-bend optic-fiber sensor, and single-mode fibers and multi-mode fibers are used as the sensitive optic-fibers. Contrast between the two sensitive fibers is presented. Result shows that the micro-bend optic-fiber sensor has good frequency response characteristics and strong ability to restore the waveform. With the frequency varying in the range of 500 - 4762 Hz, the vibration sensors using multi-mode optic-fiber as the sensitive fiber is more sensitive than that using single-mode optic-fiber. And the former has better frequency response characteristics and stronger capacity of waveform revivification. But with the frequency in the range of 287 - 500 Hz, the latter is better.
文摘变压器热点温度作为运行经济性、安全性的关键指标,是设备在线监测及状态评估中的重点。该文对变压器内部散热进行研究,着眼于饼式绕组及其油道结构,基于能量流向建立绕组温度变化的物理模型。基于这一模型,在一台内置分布式传感光纤的110kV三相ONAN变压器上开展试验研究,使用分布式光纤测温(distributed temperature sensing,DTS)技术对运行状况下的绕组整体温度分布进行实时监测,分析绕组在ONAN冷却方式下的散热状况。在变压器启动初期,绕组各处散热量较低,温升速率较快。约2 h后,各饼散热量基本与损耗相一致,散热率可达98%以上,因此将这一阶段称为准稳态。准稳态阶段,绕组整体散热率基本一致。负载变化前期不同位置散热量的差异是温度梯度形成的主要原因。基于DTS手段及散热器进出口处油温,提出绕组每饼平均对流换热系数的计算方法,基于无量纲数建立绕组内外表面局部对流换热系数的计算方法,对不同位置、负载率下两种对流换热系数的变化规律进行分析获得了绕组运行过程中对流换热系数分布规律及变化趋势。
