With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation metho...With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation method has been adopted to solve the co-site interference problem.But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System(ACICS)with large delay mismatching and antenna sway is relatively poor.This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels(ACBICS-2A).The system model was established,and the steady state weights and Interference Cancellation Ratio(ICR)were deduced by solving a time-varying differential equation.The relationship of ICR,system gain,modulation factor,interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis.Compared with traditional adaptive interference cancellation system,the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel.The maximum improved ICR is more than 25 dB.Finally,the theoretical and simulation results were verified by experiments.展开更多
With the development of wireless communication technology,an urgent problem to be solved is co-site broadband interference on independent communication platforms such as satellites,space stations,aircrafts and ships.A...With the development of wireless communication technology,an urgent problem to be solved is co-site broadband interference on independent communication platforms such as satellites,space stations,aircrafts and ships.Also,the problem of strong selfinterference rejection should be solved in the co-time co-frequency full duplex mode which realizes spectrum multiplication in 5G communication technology.In the research of such interference rejection,interference cancellation technology has been applied.In order to reject multipath interference,multitap double LMS(Least Mean Square)loop interference cancellation system is often used for cancelling RF(Radio Frequency)domain interference cancelling.However,more taps will lead to a more complex structure of the cancellation system.A novel tap single LMS loop adaptive interference cancellation system was proposed to improve the system compactness and reduce the cost.In addition,a mathematical model was built for the proposed cancellation system,the correlation function of CP2FSK(Continuous Phase Binary Frequency Shift Keying)signal was derived,and the quantitative relationship was established between the correlation function and the interference signal bandwidth and tap delay differential.The steadystate weights and the expression of the average interference cancellation ratio(ICR)were deduced in the scenes of LOS(Line of Sight)interference with antenna swaying on an independent communication platform and indoor multipath interference.The quantitative relationship was deeply analyzed between the interference cancellation performance and the parameters such as antenna swing,LMS loop gain,and interference signal bandwidth,which was verified by simulation experiment.And the performance of the proposed interference cancellation system was compared with that of the traditional double LMS loop cancellation system.The results showed that the compact single LMS loop cancellation system can achieve an average interference rejection capability comparable to the double LMS loop cancellation system.展开更多
The co-site interference exists in kinds of communication systems, especially in digital communication systems, also is one of the biggest threats ＂in electromagnetic compatibility （EMC） designation of the systems....The co-site interference exists in kinds of communication systems, especially in digital communication systems, also is one of the biggest threats ＂in electromagnetic compatibility （EMC） designation of the systems. Analyzing the co-site interference is an important process in achieving EMC performance of the system. Under the situation, the co-site interference simulation analysis of a vehicular digital communication system based on interference margin （IM） prediction method by bit error ratio （BER） was proposed in the paper. In the simulation analysis, some physical models of the vehicular communication system were established on SIMULINK environment, the upper limit of BER level for audio signals was defined as the IM, three different types of co-site interference was analyzed respectively, and the simulation results were obtained in the form of system interference bandwidth. From these results, the EMC performance evaluation of the vehicular communication system was predicted based on the IM prediction method. By comparing with the actual test results, the correctness of the simulation results was validated and the simulation analysis method can be used for reference by other communication systems was indicated.展开更多
An investigation on adsorption of NO on reduced Co-Mo/Al_2O_3 and Ru-Co-Mo/Al_2O_3 catalysts has been performed using FT-IR and MS spectroscopies. IR spectra of NO adsorption showed two bands at 1895 and 1800 cm_(-1),...An investigation on adsorption of NO on reduced Co-Mo/Al_2O_3 and Ru-Co-Mo/Al_2O_3 catalysts has been performed using FT-IR and MS spectroscopies. IR spectra of NO adsorption showed two bands at 1895 and 1800 cm_(-1), and NO--TPD profiles gave rise to several peaks at 353, 423 and 473 K, which are assigned to various Co-sites on the surface. Compared with Co-Mo/Al_2O_3, the adsorption rate, binding energy, and amount of NO adsorbed on Ru-Co-Mo/Al_2O_3 are very high.展开更多
After years of booming growth on renewable energy, the untapped land suitable for the wind farm becomes increasingly scarce in China. In order to make full use of the land, it became a realistic practice to construct ...After years of booming growth on renewable energy, the untapped land suitable for the wind farm becomes increasingly scarce in China. In order to make full use of the land, it became a realistic practice to construct wind farm together with PV station in those areas where both the wind resource and solar resource are rich. In this paper, based on the analysis of spatial distribution characteristics of wind and solar resources, the factors influencing on the layout of wind turbine and PV array and the interaction between wind turbine and PV array, a proposal for co-siting design wind farm and PV station is discussed.展开更多
该文针对单路延迟对消系统不能有效解决多径信道的超短波无线电台共址干扰消除问题,给出了等间隔多路延迟正交合成的射频干扰对消方案,进而提出了新的衰减系数求解方法。在设定时间延迟范围和参考信号路数基础上,该方法通过迭代加权实...该文针对单路延迟对消系统不能有效解决多径信道的超短波无线电台共址干扰消除问题,给出了等间隔多路延迟正交合成的射频干扰对消方案,进而提出了新的衰减系数求解方法。在设定时间延迟范围和参考信号路数基础上,该方法通过迭代加权实时有效估计多路参考信号的相关矩阵,接收信号与参考信号的相关向量,进而求解维纳霍夫方程得到各路衰减系数,有效抑制多径信道的自干扰,克服了已有方法需同时调节幅度和相位,以及相关向量和相关矩阵估计精度低的不足。另外,理论分析了衰减系数的求解过程,并推导了自干扰对消比的闭合表达式。分析和仿真结果表明,该方法在一定延迟误差情况下,可获得90 d B以上的对消比,比已有方法提高了约9 d B,有效解决了多径信道的射频干扰对消问题。展开更多
基金supported by the National Natural Science Foundation of China[Grant No.61771187]the Natural Science Foundation of Hubei Province[Grant No.2016CFB396]+1 种基金the Hubei Provincial Technology Innovation Special Major Project[Grant No.2019AAA018]the Major Project of Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy[HBSKFZD2015002].
文摘With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation method has been adopted to solve the co-site interference problem.But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System(ACICS)with large delay mismatching and antenna sway is relatively poor.This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels(ACBICS-2A).The system model was established,and the steady state weights and Interference Cancellation Ratio(ICR)were deduced by solving a time-varying differential equation.The relationship of ICR,system gain,modulation factor,interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis.Compared with traditional adaptive interference cancellation system,the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel.The maximum improved ICR is more than 25 dB.Finally,the theoretical and simulation results were verified by experiments.
基金supported by the National Natural Science Foundation of China[Grant No.61771187]the Natural Science Foundation of Hubei Province[Grant No.2016CFB396]+1 种基金the Hubei Provincial Technology Innovation Special Major Project[Grant No.2019AAA018]the Major Project of Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy[HBSKFZD2015002]。
文摘With the development of wireless communication technology,an urgent problem to be solved is co-site broadband interference on independent communication platforms such as satellites,space stations,aircrafts and ships.Also,the problem of strong selfinterference rejection should be solved in the co-time co-frequency full duplex mode which realizes spectrum multiplication in 5G communication technology.In the research of such interference rejection,interference cancellation technology has been applied.In order to reject multipath interference,multitap double LMS(Least Mean Square)loop interference cancellation system is often used for cancelling RF(Radio Frequency)domain interference cancelling.However,more taps will lead to a more complex structure of the cancellation system.A novel tap single LMS loop adaptive interference cancellation system was proposed to improve the system compactness and reduce the cost.In addition,a mathematical model was built for the proposed cancellation system,the correlation function of CP2FSK(Continuous Phase Binary Frequency Shift Keying)signal was derived,and the quantitative relationship was established between the correlation function and the interference signal bandwidth and tap delay differential.The steadystate weights and the expression of the average interference cancellation ratio(ICR)were deduced in the scenes of LOS(Line of Sight)interference with antenna swaying on an independent communication platform and indoor multipath interference.The quantitative relationship was deeply analyzed between the interference cancellation performance and the parameters such as antenna swing,LMS loop gain,and interference signal bandwidth,which was verified by simulation experiment.And the performance of the proposed interference cancellation system was compared with that of the traditional double LMS loop cancellation system.The results showed that the compact single LMS loop cancellation system can achieve an average interference rejection capability comparable to the double LMS loop cancellation system.
基金supported by EMC&EMB Lab of Beijing University of Posts and Telecommunications and Beijing Institute of Astronautic System Engineeringthe National Natural Science Foundation of China(61171051)
文摘The co-site interference exists in kinds of communication systems, especially in digital communication systems, also is one of the biggest threats ＂in electromagnetic compatibility （EMC） designation of the systems. Analyzing the co-site interference is an important process in achieving EMC performance of the system. Under the situation, the co-site interference simulation analysis of a vehicular digital communication system based on interference margin （IM） prediction method by bit error ratio （BER） was proposed in the paper. In the simulation analysis, some physical models of the vehicular communication system were established on SIMULINK environment, the upper limit of BER level for audio signals was defined as the IM, three different types of co-site interference was analyzed respectively, and the simulation results were obtained in the form of system interference bandwidth. From these results, the EMC performance evaluation of the vehicular communication system was predicted based on the IM prediction method. By comparing with the actual test results, the correctness of the simulation results was validated and the simulation analysis method can be used for reference by other communication systems was indicated.
基金Natural Science Foundation of Chinese Academy of Sciences.
文摘An investigation on adsorption of NO on reduced Co-Mo/Al_2O_3 and Ru-Co-Mo/Al_2O_3 catalysts has been performed using FT-IR and MS spectroscopies. IR spectra of NO adsorption showed two bands at 1895 and 1800 cm_(-1), and NO--TPD profiles gave rise to several peaks at 353, 423 and 473 K, which are assigned to various Co-sites on the surface. Compared with Co-Mo/Al_2O_3, the adsorption rate, binding energy, and amount of NO adsorbed on Ru-Co-Mo/Al_2O_3 are very high.
文摘After years of booming growth on renewable energy, the untapped land suitable for the wind farm becomes increasingly scarce in China. In order to make full use of the land, it became a realistic practice to construct wind farm together with PV station in those areas where both the wind resource and solar resource are rich. In this paper, based on the analysis of spatial distribution characteristics of wind and solar resources, the factors influencing on the layout of wind turbine and PV array and the interaction between wind turbine and PV array, a proposal for co-siting design wind farm and PV station is discussed.
文摘该文针对单路延迟对消系统不能有效解决多径信道的超短波无线电台共址干扰消除问题,给出了等间隔多路延迟正交合成的射频干扰对消方案,进而提出了新的衰减系数求解方法。在设定时间延迟范围和参考信号路数基础上,该方法通过迭代加权实时有效估计多路参考信号的相关矩阵,接收信号与参考信号的相关向量,进而求解维纳霍夫方程得到各路衰减系数,有效抑制多径信道的自干扰,克服了已有方法需同时调节幅度和相位,以及相关向量和相关矩阵估计精度低的不足。另外,理论分析了衰减系数的求解过程,并推导了自干扰对消比的闭合表达式。分析和仿真结果表明,该方法在一定延迟误差情况下,可获得90 d B以上的对消比,比已有方法提高了约9 d B,有效解决了多径信道的射频干扰对消问题。
