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A Novel Pulse Design Based on Hermite Functions for UWB Communications 被引量:4
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作者 JIANG Guang-xing ZHU Hong-bo CAO Wei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2006年第1期49-52,共4页
This paper presents the design of a class of pulses that are based on Hermite functions for ultra-wideband communication systems. The presented class of pulses can not only meet the power spectral emission constraints... This paper presents the design of a class of pulses that are based on Hermite functions for ultra-wideband communication systems. The presented class of pulses can not only meet the power spectral emission constraints of federal communications commission, but also have a short duration for multiple accesses. This paper gives closed form expressions of auto-and cross-correlation functions of the proposed pulses, which can be used to evaluate the performance of the correlator receiver. Furthermore, the paper investigates, under various channel conditions, the spectrum characteristic and the bit error rate of the pulses' wave forms. The investigation conditions include additive white Gaussian noise channels, multipleaccess interference channels, and fading multipath channels. Our results indicate that our systematic algorithm is flexible for designing ultra-wideband pulses that conform to spectral emission constraints and offer good bit error rate performance. 展开更多
关键词 pulse design UWB Hermite functions multiple access MULTIPATH
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Design and Simulation for the Pulse High-Voltage DC Power Supply (HVPS) of 1.2 MW/2.45 GHz HT-7U Lower Hybrid Current Drive System 被引量:2
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作者 黄懿赟 匡光力 +5 位作者 徐伟华 刘保华 林建安 吴君闩 郑光华 杨春生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2000年第6期537-548,共12页
The superconducting tokamak HT-7U [1] has been designed by the Institute of Plasma Physics since 1998 and will be set up before 2003. The 1.2 MW /2.45 GHz HT-7U LHCD (Lower hybrid current drive) system which being the... The superconducting tokamak HT-7U [1] has been designed by the Institute of Plasma Physics since 1998 and will be set up before 2003. The 1.2 MW /2.45 GHz HT-7U LHCD (Lower hybrid current drive) system which being the most efficient non-induction device can heat the plasma and drive the plasma current has been efficiently in operation 'owl and a particular design of the 2.8 MW/-35 kV high-voltage DC power supply has been already completed and will apply to the klystron of LHCD on HT-7 and the future HT-7U, and the project of the power supply has been examined and approved professionally by an authorized group of high-level specialist in the institute of Plasma Physics. The detailed design of the power supply and the simulation results are referred in the paper. 展开更多
关键词 of 1.2 MW/2.45 GHz HT-7U Lower Hybrid Current Drive System LHCD DC design and Simulation for the pulse High-Voltage DC Power Supply HVPS HT
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Design of control sequence of pulses for the population transfer of high dimensional spin 1/2 quantum systems
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作者 Cong Shuang Lou Yuesheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1226-1234,共9页
On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half c... On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half counter-intuitive sequences of pulse to transfer the population of the 3-qubit system coherently. The effectiveness of the designed control sequence is verified through the system simulation experiment of the evolution of state. In principle, the design method of the control pulse sequence proposed can be generalized to use in the quantum systems of higher dimension. 展开更多
关键词 quantum system control population transfer pulse sequence design intuitive sequence half counter-intuitive sequence
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Semi-definite programming based pulse waveform design and its further analysis
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作者 王利利 沙学军 吴宣利 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期578-581,共4页
In order to provide a judicious pulse waveform design required for ultra-wideband(UWB)communication to enable the UWB spectral mask compatible and coexistent with other existing wireless communication systems,a semi-d... In order to provide a judicious pulse waveform design required for ultra-wideband(UWB)communication to enable the UWB spectral mask compatible and coexistent with other existing wireless communication systems,a semi-definite programming(SDP)based pulse waveform design method for UWB radios is introduced and a further analysis is given in this paper.By using Sedumi and Yalmip toolboxes of Matlab,the procedure of solving the SDP problem is simplified.Simulation results show that this SDP based pulse waveform design method can be used to design pulses that fulfill the Federal Communications Commission(FCC)spectral mask strictly and optimize the power efficiency at the same time.This paper also analyzes the influences of the power efficiency duing to the changes of sampling interval and the number of combined pulses,and then the optimal sampling interval that maximizes the transmission power can be found. 展开更多
关键词 ULTRA-WIDEBAND pulse waveform design FCC spectral mask semi-definite programming
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Modeling, analysis, and screening of cyclic pressure pulsing with nitrogen in hydraulically fractured wells
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作者 Emre Artun Ali Aghazadeh Khoei Kutay Kose 《Petroleum Science》 SCIE CAS CSCD 2016年第3期532-549,共18页
Cyclic pressure pulsing with nitrogen is studied for hydraulically fractured wells in depleted reservoirs.A compositional simulation model is constructed to represent the hydraulic fractures through local-grid refinem... Cyclic pressure pulsing with nitrogen is studied for hydraulically fractured wells in depleted reservoirs.A compositional simulation model is constructed to represent the hydraulic fractures through local-grid refinement.The process is analyzed from both operational and reservoir/hydraulic-fracture perspectives.Key sensitivity parameters for the operational component are chosen as the injection rate,lengths of injection and soaking periods and the economic rate limit to shut-in the well.For the reservoir/hydraulic fracturing components,reservoir permeability,hydraulic fracture permeability,effective thickness and half-length are used.These parameters are varied at five levels.A full-factorial experimental design is utilized to run 1250 cases.The study shows that within the ranges studied,the gas-injection process is applied successfully for a 20-year project period with net present values based on the incremental recoveries greater than zero.It is observed that the cycle rate limit,injection and soaking periods must be optimized to maximize the efficiency.The simulation results are used to develop a neural network based proxy model that can be used as a screening tool for the process.The proxy model is validated with blind-cases with a correlation coefficient of 0.96. 展开更多
关键词 Cyclic pressure pulsing Nitrogen injection Hydraulically-fractured wells Experimental design Artificial neural networks
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