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Research on the influence of ocean temperature on XCTD profiler single-mode fiber transmission channel 被引量:2
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作者 郑羽 付孝洪 +4 位作者 高宇 方静 王金海 李红志 刘宁 《Marine Science Bulletin》 CAS 2015年第1期50-60,共11页
XCTD, as one of the most important instruments for the deep sea exploration, is an important device for deep-sea hydrological data acquisition. But some difficult technical problems of traditional metal enameled wire ... XCTD, as one of the most important instruments for the deep sea exploration, is an important device for deep-sea hydrological data acquisition. But some difficult technical problems of traditional metal enameled wire channel have become the major bottleneck for XCTD development. Aiming at this problem, this paper puts forward with using single-mode fiber as the transmission channel of XCTD. Firstly, this paper makes a brief analysis on the problems of using enameled wire as transmission channel faces. Secondly, it analyzes the advantages of the single mode fiber technology. Finally, it makes theoretical research and experimental verification of the influence of seawater temperature change on the optical fiber transmission channel. The experimentat results show that the error rate at the transmission rate of 10 MB/S is 0, and the loss can be negligible when the single-mode fiber channel is used in the sea water and the seawater temperature changes from 0 to 20℃. This method will greatly increase the rate of signal transmission and the transmission stability. And this paper shows that using the single-mode fiber as the transmission channel of XCTD has certain feasibility. 展开更多
关键词 XCTD profiler signal-mode optical fiber effect of ocean temperature transmission performance
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A new method for improving the inductively coupled data transmission rate of mooring buoy based on carrier signal frequency selection 被引量:1
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作者 Rong Du Xingfei Li +1 位作者 Shaobo Yang Hongyu Li 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2020年第2期96-103,共8页
In the inductively coupled data transmission system of the mooring buoy, the carrier signal frequency of the transmission channel is limited due to the inherent characteristics of the system, resulting in limited chan... In the inductively coupled data transmission system of the mooring buoy, the carrier signal frequency of the transmission channel is limited due to the inherent characteristics of the system, resulting in limited channel bandwidth. The limited channel bandwidth limits the increase in inductively coupled data transmission rate.In order to improve the inductively coupled data transmission rate of mooring buoy as much as possible without damaging the data transmission performance, a new method was proposed in this paper. The method is proposed to improve the data transmission rate by selecting the appropriate carrier signal frequencies based on the principle of maximizing the amplitude value of amplitude-frequency characteristic curve of the system. Research has been done according to this method as follows. Firstly, according to the inductively coupled transmission mooring buoy structure, the inductively coupled data transmission circuit model was established. The binary frequency shift keying(2FSK) digital signal modulation mode was selected. Through theoretical analysis, the relation between the carrier signal frequency and the data transmission performance, the relation between the carrier signal frequency and the 2FSK signal bandwidth were obtained. Secondly, the performance and the bandwidth of the signal transmission were studied for the inherent characteristics of the actual inductively coupled data transmission system. The amplitude-frequency characteristic of the system was analyzed by experiments. By selecting the appropriate carrier signal frequency parameters, an excellent data transmission performance was guaranteed and a large 2FSK signal bandwidth was obtained. Finally, an inductively coupled data transmission rate optimization experiment and a bit error rate analysis experiment were designed and carried out. The results show that the high-speed and reliable data transmission of the system was realized and the rate can reach 100 kbps. 展开更多
关键词 Mooring buoy Inherent characteristics Inductively coupled data transmission rate Carrier signal frequency Data transmission performance Amplitude-frequency characteristic
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Real-time performance of periodic data transmission in EPA industrial Ethernet 被引量:2
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作者 刘宁 仲崇权 莫亚林 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期336-342,共7页
To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By... To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By analyzing information transmission regularity and EPA deterministic scheduling mechanism,periodic messages were categorized as different modes according to their entering-queue time.The scheduling characteristics and delivery time of each mode and their interacting relations were studied,during which the models of real-time performance of periodic information transmission in EPA system were established.On this basis,an experimental platform is developed to test the delivery time of periodic messages transmission in EPA system.According to the analysis and the experiment,the main factors that limit the real-time performance of EPA periodic data transmission and the improvement methods were proposed. 展开更多
关键词 Ethernet for plant automation(EPA) industrial Ethernet periodic data transmission real-time performance delivery time
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A simple and effective model for Jones matrix to evaluate the transmission performance of Savart polariscope
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作者 吴海英 张淳民 李杰 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期381-388,共8页
Starting from the wave normal tracing treatment in the Savart polariscope that relates the Jones matrix to its transmission performance, this paper establishes a simple and effective model for the Jones matrix at an a... Starting from the wave normal tracing treatment in the Savart polariscope that relates the Jones matrix to its transmission performance, this paper establishes a simple and effective model for the Jones matrix at an arbitrary incidence in the spatial domain. Analytical expressions of all the matrix components are determined with the consideration of all the main impact factors. This model needs only a few parameters hence it is convenient to be employed to evaluate the propagation performance of any birefringent optical system. The simulated results obtained with it demonstrate that this model gives a precise representation of the characteristic of light propagation in the Savart polariscope. This would provide useful suggestions for the design, calibration, and performance improvement of any other birefringent polarisation element and optical system. 展开更多
关键词 wave normal tracing method Jones matrix transmission performance Savart polariscope
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Methods to Improve the Long Distance Time-Varying Channel Transmission Performance of Expendable Profiler
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作者 ZHENG Yu ZHANG Xiao-yang +2 位作者 WANG Xiao-rui GUO Xing-xin LI Hong-zhi 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期753-761,共9页
To improve the transmission performance of XCTD channel, this paper proposes a method to measure directly and fit the channel transmission characteristics by using frequency sweeping method. Sinusoidal signals with a ... To improve the transmission performance of XCTD channel, this paper proposes a method to measure directly and fit the channel transmission characteristics by using frequency sweeping method. Sinusoidal signals with a frequency range of 100 Hz to 10 k Hz and an interval of 100 Hz are used to measure transmission characteristics of channels with lengths of 300 m, 800 m, 1300 m, and 1800 m. The correctness of the fitted channel characteristics by transmitting square wave, composite waves of different frequencies, and ASK modulation are verified. The results show that when the frequency of the signal is below 1500 Hz, the channel has very little effect on the signal. The signal compensated for amplitude and phase at the receiver is not as good as the uncompensated signal.Alternatively, when the signal frequency is above 1500 Hz, the channel distorts the signal. The quality of signal compensated for amplitude and phase at receiver is better than that of the uncompensated signal. Thus, we can select the appropriate frequency for XCTD system and the appropriate way to process the received signals. Signals below1500 Hz can be directly used at the receiving end. Signals above 1500 Hz are used after amplitude and phase compensation at the receiving end. 展开更多
关键词 expandable conductivity temperature depth(XCTD)profiler time-varying channel modeling frequency sweeping method amplitude and phase compensation transmission performance
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Design optimization of plastic scintillators with wavelength-shifting fibers and silicon photomultiplier readouts in the top veto tracker of the JUNO-TAO experiment 被引量:2
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作者 Guang Luo Y.K.Hor +10 位作者 Pei-Zhi Lu Zhi-Min Wang Ru-Hui Li Min Li Yi-Chen Li Liang Zhan Wei Wang Yue-Huan Wei Yu Chen Xiang Xiao Feng-Peng An 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期99-112,共14页
Plastic scintillators(PSs)embedded with wavelength-shifting fibers are widely used in high-energy particle physics,such as in muon taggers,as well as in medical physics and other applications.In this study,a simulatio... Plastic scintillators(PSs)embedded with wavelength-shifting fibers are widely used in high-energy particle physics,such as in muon taggers,as well as in medical physics and other applications.In this study,a simulation package was built to evaluate the effects of the diameter and layout of optical fibers on the light yield with different configurations.The optimal optical configuration was designed based on simulations and validated using two PS prototypes under certain experimental condi-tions.A top veto tracker(TVT)for the JUNO-TAO experiment,comprising four layers of 160 strips of PS,was designed and evaluated.The threshold was evaluated when the muon tagging efficiency of a PS strip was>99%.The efficiency of three layer out of four layer of TVT is>99%,even with a tagging efficiency of a single strip as low as 97%,using a threshold of 10 photoelectrons and assuming a 40%silicon PM photon detection efficiency. 展开更多
关键词 Plastic scintillator WLS fiber Light yield Optical transmission performance Muon tagging efficiency JUNO-TAO
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Experimental performance evaluation of quadrature amplitude modulation signal transmission in a silicon microring 被引量:3
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作者 Chengcheng Gui Jian Wang 《Photonics Research》 SCIE EI 2016年第5期168-172,共5页
We comprehensively characterize the transmission performance of m-ary quadrature amplitude modulation(m-QAM) signals through a silicon microring resonator in the experiment. Using orthogonal frequency-division multipl... We comprehensively characterize the transmission performance of m-ary quadrature amplitude modulation(m-QAM) signals through a silicon microring resonator in the experiment. Using orthogonal frequency-division multiplexing based on offset QAM(OFDM/OQAM) which is modulated with m-QAM modulations, we demonstrate low-penalty data transmission of OFDM/OQAM 64-QAM, 128-QAM, 256-QAM, and 512-QAM signals in a silicon microring resonator. The observed optical signal-to-noise ratio(OSNR) penalties are 1.7 dB for 64-QAM,1.7 dB for 128-QAM, and 3.1 dB for 256-QAM at a bit-error rate(BER) of 2 × 10^(-3) and 3.3 dB for 512-QAM at a BER of 2 × 10^(-2). The performance degradation due to the wavelength detuning from the microring resonance is evaluated, showing a wavelength range of ~0.48 nm with BER below 2 × 10^(-3). Moreover, we demonstrate data transmission of 191.2-Gbit/s simultaneous eight wavelength channel OFDM/OQAM 256-QAM signals in a silicon microring resonator, achieving OSNR penalties less than 2 dB at a BER of 2 × 10^(-2). 展开更多
关键词 QAM Experimental performance evaluation of quadrature amplitude modulation signal transmission in a silicon microring OSNR BER OFDM WDM
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Research on transmission performance of a surface acoustic wave sensing system used in manufacturing environment monitoring
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作者 Cong-cong LUAN Xin-hua YAO +1 位作者 Qiu-yue CHEN Jian-zhong FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2017年第6期443-453,共11页
Surface acoustic wave (SAW) sensors show great promise in monitoring fast-rotating or moving machinery in manufacturing environments, and have several advantages in the measurement of temperature, torque, pressure, ... Surface acoustic wave (SAW) sensors show great promise in monitoring fast-rotating or moving machinery in manufacturing environments, and have several advantages in the measurement of temperature, torque, pressure, and strain because of their passive and wireless capability. However, very few studies have systematically attempted to evaluate the characteristics of SAW sensors in a metal environment and rotating structures, both of which are common in machine tools. Simulation of the influence of the metal using CST software and a series of experiments with an SAW temperature sensor in real environments were designed to investigate the factors that affect transmission pertbrmance, including antenna angles, orientations, rotation speeds, and a metallic plate, along with the interrogator antenna-SAW sensor antenna separation distance. Our experimental measure- ments show that the sensor's optimal placement in manufacturing environments should take into account all these factors in order to maintain system measurement and data transmission capability. As the first attempt to systematically investigate the transmis- sion characteristics of the SAW sensor used in manufacturing environment, this study aims to guide users of SAW sensor appli- cations and encourage more research in the field of wireless passive SAW sensors in monitoring applications. 展开更多
关键词 transmission performance Surface acoustic wave (SAW) SENSOR Manufacturing environment MONITORING
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Effect of optical losses on the transmission performance of a radio-over-fiber distributed antenna system
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作者 龚志山 徐坤 +5 位作者 孟学军 裴寅清 孙小强 戴一堂 纪越峰 林金桐 《Chinese Optics Letters》 SCIE EI CAS CSCD 2013年第2期8-11,共4页
The effects of optical losses oil a directly-modulated radio-over-fiber (RoF) system used for distributed antenna networks are determined. The results show that with a properly designed bidirectional amplifier, the ... The effects of optical losses oil a directly-modulated radio-over-fiber (RoF) system used for distributed antenna networks are determined. The results show that with a properly designed bidirectional amplifier, the RoF link can tolerate over 20 and 16 dB of optical losses for down- and up-links, respectively. Simulation results are also consistent with the experimental data. These findings can contribute to tile design of RoF distributed antenna systems with different topologies. 展开更多
关键词 ROF Effect of optical losses on the transmission performance of a radio-over-fiber distributed antenna system OVER LINK WIFI
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Sound transmission performance on cavity ferrocement panels with ties
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作者 Kandaswamy S Ramachandraiah A (Building Technology Div., Dept. of Civil Engg., I.I.T. Madras, Chennai-600 036 India) 《Chinese Journal of Acoustics》 2003年第2期132-139,共8页
Ferrocement panels have been used in low cost housing construction in developing countries. This study focuses on the sound transmission performance of cavity ferrocement panels with ties. In this study, panels have b... Ferrocement panels have been used in low cost housing construction in developing countries. This study focuses on the sound transmission performance of cavity ferrocement panels with ties. In this study, panels have been cast and tested in transmission loss suite specially designed and constructed for testing their sound transmission performance experimentally. The measured results agree well with the theoretical model. 展开更多
关键词 with in been Sound transmission performance on cavity ferrocement panels with ties IS of on
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Influence of GaAs substrate on the transmission performance of epitaxially grown Fabry-P'erot filter
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作者 王伟 黄永清 +5 位作者 段晓峰 颜强 任晓敏 蔡世伟 郭经纬 黄辉 《Chinese Optics Letters》 SCIE EI CAS CSCD 2011年第11期81-84,共4页
The influence of GaAs substrate on the transmission performance of a multi-film Fabry-P'erot filter (FPF),fabricated by metalorganic chemical vapor deposition epitaxial growth on GaAs substrate,is investigated usin... The influence of GaAs substrate on the transmission performance of a multi-film Fabry-P'erot filter (FPF),fabricated by metalorganic chemical vapor deposition epitaxial growth on GaAs substrate,is investigated using the transfer matrix method.On the basis of the theoretical simulation,we determine that the quality of the resonant transmission peak of this epitaxially grown FPF (EG-FPF) deteriorates through splitting when the substrate is taken into account.Rapid periodic oscillation of peak-transmittivity along with the alteration of substrate thickness is also observed in the simulation results.Finally,a remarkably improved transmission performance of the EG-FPF is obtained by thinning the substrate down to a suitable thickness range through well-controlled grinding and polishing. 展开更多
关键词 GAAS Influence of GaAs substrate on the transmission performance of epitaxially grown Fabry-P’erot filter
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Analysis of the kinematic characteristics of a high-speed parallel robot with Sch6nflies motion: Mobility, kinematics, and singularity 被引量:6
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作者 Fugui XIE Xin-Jun LIU 《Frontiers of Mechanical Engineering》 SCIE CSCD 2016年第2期135-143,共9页
This study introduces a high-speed parallel robot with Schonflies motion. This robot exhibits a promising prospect in realizing high-speed pick-and- place manipulation for packaging production lines. The robot has fou... This study introduces a high-speed parallel robot with Schonflies motion. This robot exhibits a promising prospect in realizing high-speed pick-and- place manipulation for packaging production lines. The robot has four identical limbs and a single platform. Its compact structure and single-platform concept provides this robot with good dynamic response potential. A line graph method based on Grassmann line geometry is used to investigate the mobility characteristics of the proposed robot. A generalized Blanding rule is also introduced into this procedure to realize mutual conversion between the line graphs for motions and constraints. Subsequently, the inverse kinematics is derived, and the singularity issue of the robot is investigated using both qualitative and quantitative approaches. Input and output transmission singularity indices are defined based on the reciprocal product in screw theory and the virtual coefficient by considering motion/force transmission performance. Thereafter, the singular loci of the proposed robot with specific geometric parameters are derived. The mobility analysis, inverse kinematics modeling, and singularity analysis conducted in this study are helpful in developing the robot. 展开更多
关键词 parallel robot MOBILITY inverse kinematics singularity transmission performance
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