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ENERGY-EFFICIENT MICROWAVE COMPONENTS FOR MOBILE COMMUNICATION 被引量:2
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作者 Yuanan Liu Quanyuan Feng Fadhel M. Ghannouchi 《China Communications》 SCIE CSCD 2017年第2期19-20,共2页
In the coexisted world of 3G,4G,5G and many other specialized wireless communication systems,billions of connections could be existing for various information transmission types.Unluckily,data show that the increase o... In the coexisted world of 3G,4G,5G and many other specialized wireless communication systems,billions of connections could be existing for various information transmission types.Unluckily,data show that the increase of network capacity is heavily more than the increase of the network energy efficiency in recent years,which could lead to more energy consumption per transmitted bit in the future network.As basic units in mobile communication systems,microwave/RF components and modules play key roles 展开更多
关键词 HIGH data ENERGY-EFFICIENT microwave COMPONENTS FOR MOBILE communication PAPR SHOW DPA
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Study of High-Temperature Superconductor Diplexers for Satellite Communications 被引量:1
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作者 刘娟秀 羊恺 +3 位作者 罗正祥 补世荣 宁俊松 张天良 《Journal of Electronic Science and Technology of China》 2005年第3期260-263,共4页
The high-temperature superconductor (HTSC) resonator and diplexer are simulated by full-wave tools. A newly developed miniature HTSC diplexer is designed and fabricated on double sided YBa2Cu3O7 (YBCO) film (YBCO... The high-temperature superconductor (HTSC) resonator and diplexer are simulated by full-wave tools. A newly developed miniature HTSC diplexer is designed and fabricated on double sided YBa2Cu3O7 (YBCO) film (YBCO/LaAlO3/YBCO), the thickness of which is 400 nm for YBCO and 0.5 mm for the LaAlO3. The measured results show a good agreement with the simulation. The volume and mass of the diplexers are greatly reduced by miniaturized configuration. 展开更多
关键词 high-temperature superconductor microwave DIPLEXER satellite communication
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Design of Transmitter Combiner for 800MHz Trucking Mobile Communication
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作者 马汉炎 吴群 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期28-32,共5页
The structural composition, scheme selection and component design of a five-channel transmitter combiner for 800MHz trucking mobile communication system (TMC) is proposed. More attentions have been paid to the analysi... The structural composition, scheme selection and component design of a five-channel transmitter combiner for 800MHz trucking mobile communication system (TMC) is proposed. More attentions have been paid to the analysis and design of the high-Q microwave resonant cavity with accurate tuning structure. Also, a model transmitter combiner designed by the authors is proposed. Test results of the combiner are given. It has been proved that the technical specifications of the combiner have reached an advanced technical level compared with the products of the same kind imported from abroad. 展开更多
关键词 ss:Transmitter COMBINER mobile communication microwave RESONANT CAVITY
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The Experimental Exploration and Discovery of DNA Communication between the Plants
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作者 Xinzhou Yuan Jiafeng Yuan +3 位作者 Zhongxian Deng Shikui Wang Zhen Yang Qiao Bi 《Journal of Modern Physics》 CAS 2022年第11期1499-1517,共19页
For the first time, through the invention of Compensating Bio-information Energy (CBE) technology and bioinformatics breeding machine, we have completed a number of experiments by using plant signals to transfer plant... For the first time, through the invention of Compensating Bio-information Energy (CBE) technology and bioinformatics breeding machine, we have completed a number of experiments by using plant signals to transfer plant genetic traits in the same family or across families, and discovered the transfer phenomenon of life genetic information. The test results show that plants can change from random variation to controllable and directional variation, thus opening up plant asexual, no molecular transfer, fast and low-cost breeding. The new approach provides new evidence for the connection of information energy waves between plant DNA, which deserves the attention and in-depth study of the scientific community. 展开更多
关键词 Biological Signal Biological microwave Radiation DNA communication Bio-Information Breeding Machine
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Changes in gap junctional intercellular communication in rabbits lens epithelial cells induced by low power density microwave radiation
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作者 叶娟 姚克 +1 位作者 曾群力 鲁德强 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第12期1873-1876,154,共4页
OBJECTIVE: To demonstrate the changes in gap junctional intercellular communication (GJIC) mediated by low power density microwave radiation in rabbits lens epithelial cells (LECs) and its mechanisms. METHODS: Rabbits... OBJECTIVE: To demonstrate the changes in gap junctional intercellular communication (GJIC) mediated by low power density microwave radiation in rabbits lens epithelial cells (LECs) and its mechanisms. METHODS: Rabbits' eyes were exposed to 5 mW/cm(2) and 10 mW/cm(2) power densities of microwave radiation for 3 hours. The fluorescence-recovery-after-photobleaching (FRAP) method was used to determine the GJIC. The localization and function of connexin 43 in LECs was detected by laser scanning confocal microscopy. RESULTS: The GJIC of rabbits LECs was inhibited by microwave radiation especially in the 10 mW/cm(2) irradiated samples. A decrease in connexin 43-positive staining was seen in 5 mW/cm(2) x 3 h treated LECs. Intracellular space accumulation and cytoplasmic internalization were clearly demonstrated in 10 mW/cm(2) group. CONCLUSIONS: Low power densities microwave radiation (5 mW/cm(2) and 10 mW/cm(2)) induces damage to connexin 43 and inhibits the GJIC of rabbits LECs. These changes result in an osmotic imbalance within the lens and induce early cataract. 5 mW/cm(2) or 10 mW/cm(2) microwave radiation is cataractogenic. 展开更多
关键词 ANIMALS CATARACT Cell communication Connexin 43 Epithelial Cells Fluorescent Antibody Technique Indirect Gap Junctions Lens Crystalline microwaves RABBITS
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Photonic generation of ASK microwave signals with SSB format
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作者 Weilei Gou Yuan Yu Xinliang Zhang 《Frontiers of Optoelectronics》 EI CSCD 2023年第3期35-41,共7页
Optical beating is the usual approach to generation of microwave signals.However,the highest frequency achievable for microwave signals is limited by the bandwidths of optoelectronic devices.To maximize the microwave ... Optical beating is the usual approach to generation of microwave signals.However,the highest frequency achievable for microwave signals is limited by the bandwidths of optoelectronic devices.To maximize the microwave frequency with a limited bandwidth of a photodetector(PD)and relieve the bandwidth bottleneck,we propose to generate microwave signals with the single sideband(SSB)format by beating a continuous wave(CW)light with an optical SSB signal.By simply adjusting the frequency diference between the CW light and the carrier of the optical SSB signal,the frequency of the generated microwave SSB signal is changed correspondingly.In the experiment,amplitude shift keying(ASK)microwave signals with the SSB format are successfully generated with diferent carrier frequencies and coding bit rates,and the recovered coding information agrees well with the original pseudo random binary sequence(PRBS)of 2^(7)−1 bits.The proposed approach can signifcantly relieve the bandwidth restriction set by optoelectronic devices in high-speed microwave communication systems. 展开更多
关键词 Single sideband modulation Amplitude shift keying microwave signal generation microwave communication
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Communication infrastructure for situational awareness enhancement in WAMS with optimal PMU placement 被引量:9
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作者 Bhargav Appasani Amitkumar Vidyakant Jha +1 位作者 Sunil Kumar Mishra Abu Nasar Ghazali 《Protection and Control of Modern Power Systems》 2021年第1期124-135,共12页
Real time monitoring and control of a modern power system has achieved significant development since the incorporation of the phasor measurement unit (PMU). Due to the time-synchronized capabilities, PMU has increased... Real time monitoring and control of a modern power system has achieved significant development since the incorporation of the phasor measurement unit (PMU). Due to the time-synchronized capabilities, PMU has increased the situational awareness (SA) in a wide area measurement system (WAMS). Operator SA depends on the data pertaining to the real-time health of the grid. This is measured by PMUs and is accessible for data analytics at the data monitoring station referred to as the phasor data concentrator (PDC). Availability of the communication system and communication delay are two of the decisive factors governing the operator SA. This paper presents a pragmatic metric to assess the operator SA and ensure optimal locations for the placement of PMUs, PDC, and the underlying communication infrastructure to increase the efficacy of operator SA. The uses of digital elevation model (DEM) data of the surface topography to determine the optimal locations for the placement of the PMU, and the microwave technology for communicating synchrophasor data is another important contribution carried out in this paper. The practical power grid system of Bihar in India is considered as a case study, and extensive simulation results and analysis are presented for validating the proposed methodology. 展开更多
关键词 Situational awareness Phasor measurement unit Optimal placement microwave communication
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Effects on the thermal expansion coefficient and dielectric properties of CLST/PTFE filled with modified glass fiber as microwave material 被引量:3
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作者 Liu Zheng Jing Zhou +2 位作者 Jie Shen Yanyuan Qi Wen Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第5期1111-1114,共4页
Ceramic and polytetrafluoroethylene composites as dielectric materials have a low dielectric loss at high frequency and play an important role in the modern communication field.However,room temperature phase transform... Ceramic and polytetrafluoroethylene composites as dielectric materials have a low dielectric loss at high frequency and play an important role in the modern communication field.However,room temperature phase transformation of PTFE resins,which is accompanied by a large volume change(>400 ppm/℃),seriously affects the dimensional stability and performance stability of materials.The LD125 modified glass fiber(GF)was introduced to the CaO-Li2 O-Sm2O3-TiO2(CLST)/PTFE composite,to reduce the thermal expansion coefficient(CTE)of the composites.The tri-phase composites(CLST/PTFE/GF)show the low dielectric loss and excellent machine-ability.The effect of GF content on the dielectric properties and CTE was also investigated.The CLST/PTFE filled with 5%GF exhibits the best overall performance,which is a promising microwave dielectric material for microwave communication. 展开更多
关键词 microwave communication Thermal expansion COEFFICIENT CLST PTFE DIELECTRIC loss DIELECTRIC CONSTANT
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Control System Design and Implementation at Flexible, Distributed Offshore Sensor Test Sites in the Yangtze Estuary Area
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作者 HU Qingsong JIANG Chao +5 位作者 DU Lin LI Jun CHEN Leilei XIANG Peng ZHANG Hongcheng RAHMAN Hafiz Abd ur 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期285-295,共11页
Marine in situ testing is a necessary step for stereotyping newly developed marine sensors. The use of test sites in the Yangtze Estuary area, which has high turbidity and abundant nutrients, can effectively reduce th... Marine in situ testing is a necessary step for stereotyping newly developed marine sensors. The use of test sites in the Yangtze Estuary area, which has high turbidity and abundant nutrients, can effectively reduce the needed testing time owing to its harsh conditions. Five test stations were established, and a floating buoy and fixed test equipment were designed. A control system, including a sensor connection, data processor, video remote transmission, and corresponding control algorithm, was developed. The control system enabled the nondestructive monitoring of biological attachments and bidirectional, real-time communication between an upper server on land and the control system at the test sites. The dissolved oxygen(DO), temperature, and pH data of DOS600 and DPS600 sensors were compared with those of AP2000 sensors. Temperature recording using the DOS600 sensor was performed nearly as well as that of the AP2000 sensor. The mean DO values(standard deviations) were 8.414 mg L-1(2.068) and 6.896 mg L-1(1.235) for the DOS600 and AP2000 sensors, respectively, indicating that the DOS600 performance was unsatisfactory. The pH recording of the DPS600 was slightly worse than that of the AP2000 sensor. Experimental results showed that the DO value was more easily affected by the buoy movement of waves compared to the pH and temperature. Moreover, data fluctuations showed that the DO and pH parameters were more vulnerable to biofouling than temperature. Waves and biofouling create a harsh test environment, and the performance difference between the developed sensors and a standard sensor can be obtained in a short time period. 展开更多
关键词 offshore sensor test sites Yangtze Estuary control system communication protocol microwave sensor detection data analysis
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Multi-band microwave photonic satellite repeater scheme employing intensity Mach-Zehnder modulators
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作者 Yin Jie Dong Tao +6 位作者 Zhang Bin Hao Yan Cao Guixing Cheng Zijing Xu Kun Zhou Yue Dai Jian 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2017年第2期89-95,共7页
To solve the satellite repeater's flexible and wideband frequency conversion problem, we propose a novel microwave photonic repeater system, which can convert the upload signal's carrier to six different frequencies... To solve the satellite repeater's flexible and wideband frequency conversion problem, we propose a novel microwave photonic repeater system, which can convert the upload signal's carrier to six different frequencies. The scheme employs one 20 GHz bandwidth dual-drive Mach-Zehnder modulator (MZM) and two 10 GHz bandwidth MZMs. The basic principle of this scheme is filtering out two optical sidebands after the optical carrier suppression (OCS) modulation and combining two sidebands modulated by the input radio frequency (RF) signal. This structure can realize simultaneous multi-band frequency conversion with only one frequency-fixed microwave source and prevent generating harmful interference sidebands by using two corresponding optical filters after optical modulation. In the simulation, one C-band signal of 6 GHz carrier can be successfully converted to 12 GHz (Ku-band), 28 GHz, 34 GHz, 40 GHz, 46 GHz (Ka-band) and 52 GHz (V-band), which can be an attractive method to realize multi-band microwave photonic satellite repeater. Alternatively, the scheme can be configured to generate multi-band local oscillators (LOs) for widely satellite onboard clock distribution when the input RF signal is replaced by the internal clock source. 展开更多
关键词 fiber optics and optical communication radio frequency photonics microwave photonics
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HTS filter and front-end subsystem for GSM1800 wireless base station 被引量:1
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作者 何豫生 黎红 +10 位作者 何艾生 李顺洲 李春光 张雪强 张太平 阎令文 朱文秀 周远 梁惊涛 洪嘉生 M.J.Lancaster 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第6期638-645,共8页
The first HTS front-end subsystem for wireless base station in China was developed. This demonstration system, which aims at the application in GSM1800 mobile communication base station, consists of a single RF path, ... The first HTS front-end subsystem for wireless base station in China was developed. This demonstration system, which aims at the application in GSM1800 mobile communication base station, consists of a single RF path, i.e. one filter and one LNA, integrated with the pulse tube cooler. The subsystem works at a pass band of 1710-1785 MHz with a gain of 18 dB and at a temperature of 70 K. The accomplishment of such a demonstration subsystem can boost the development of HTS commercial subsystem. 展开更多
关键词 high temperature superconductor filter microwave subsystem mobile communication base station DEMONSTRATION system.
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