Emission of the electromagnetic pulses （EMP） due to laser-target interaction in laser facility had been evaluated using a cone antenna in this work. The microwave in frequencies ranging from several hundreds of MHz ...Emission of the electromagnetic pulses （EMP） due to laser-target interaction in laser facility had been evaluated using a cone antenna in this work. The microwave in frequencies ranging from several hundreds of MHz to 2 GHz was recorded when long-pulse lasers with several thousands of joules illuminated the solid targets, meanwhile the voltage signals from 1V to 4V were captured as functions of laser energy and backlight laser, where the corresponding electric field strengths were obtained by simulating the cone antenna in combination with conducting a mathematical process （Tiknohov Regularization with L curve）. All the typical coupled voltage oscillations displayed multiple peaks and had duration of up to 80ns before decaying into noise and mechanisms of the EMP generation was schematically interpreted in basis of the practical measuring environments. The resultant data were expected to offer basic know-how to achieve inertial confinement fusion.展开更多
针对非视距NLOS(Non Line of Sight)隧道环境的特殊性,基于传播图理论提出通过细化散射点间传递函数的方法提高隧道信道建模精度。构建隧道几何模型,并将模型划分为多个散射点集合,电磁波的传播路线可表述为点集合的排列,通过相邻点集...针对非视距NLOS(Non Line of Sight)隧道环境的特殊性,基于传播图理论提出通过细化散射点间传递函数的方法提高隧道信道建模精度。构建隧道几何模型,并将模型划分为多个散射点集合,电磁波的传播路线可表述为点集合的排列,通过相邻点集合间子传递函数的级联可得到该路线的传递函数。引入点集合间转移概率的概念描述其可视情况,用传播路线上相邻点集合间转移概率之积调整该路线的传递函数。所有路线传递函数之和即为信道频域传递函数,进而得到信道冲激相应CIR(Channel Impulse Response),并与相同环境下实际信道测量结果进行对比。在此基础上分析多天线相关性、角度分布与信道容量,发现隧道中密集的反射会导致天线间相关性较高及信道矩阵退化。展开更多
基金We would like to thank Dr. Peng Wang at University of Electric Science and Technology of China （UESTC） and Dr. Ziyu Chen at China Academy of Engineering Physics for their help in processing the data and understanding the potential mechanisms. This work was financially supported by the Fundamental Research Funds for the Central Universities （No. ZYGX2015J108） and National Natural Science Foundation of China （Nos. 11575166 and 5158 1140）.
文摘Emission of the electromagnetic pulses （EMP） due to laser-target interaction in laser facility had been evaluated using a cone antenna in this work. The microwave in frequencies ranging from several hundreds of MHz to 2 GHz was recorded when long-pulse lasers with several thousands of joules illuminated the solid targets, meanwhile the voltage signals from 1V to 4V were captured as functions of laser energy and backlight laser, where the corresponding electric field strengths were obtained by simulating the cone antenna in combination with conducting a mathematical process （Tiknohov Regularization with L curve）. All the typical coupled voltage oscillations displayed multiple peaks and had duration of up to 80ns before decaying into noise and mechanisms of the EMP generation was schematically interpreted in basis of the practical measuring environments. The resultant data were expected to offer basic know-how to achieve inertial confinement fusion.
文摘针对非视距NLOS(Non Line of Sight)隧道环境的特殊性,基于传播图理论提出通过细化散射点间传递函数的方法提高隧道信道建模精度。构建隧道几何模型,并将模型划分为多个散射点集合,电磁波的传播路线可表述为点集合的排列,通过相邻点集合间子传递函数的级联可得到该路线的传递函数。引入点集合间转移概率的概念描述其可视情况,用传播路线上相邻点集合间转移概率之积调整该路线的传递函数。所有路线传递函数之和即为信道频域传递函数,进而得到信道冲激相应CIR(Channel Impulse Response),并与相同环境下实际信道测量结果进行对比。在此基础上分析多天线相关性、角度分布与信道容量,发现隧道中密集的反射会导致天线间相关性较高及信道矩阵退化。
