Constructing a photoconductive semiconductor switch (PCSS)-metal coil structure, we discovered anew phenomenon of electromagnetic oscillation in vanadium-compensation semi-insulating (VCSI) PCSS. Here thePCSS responds...Constructing a photoconductive semiconductor switch (PCSS)-metal coil structure, we discovered anew phenomenon of electromagnetic oscillation in vanadium-compensation semi-insulating (VCSI) PCSS. Here thePCSS responds to laser pulse and high-voltage signal while the metal coil generates an oscillating voltage pulseenvelope signal. The generation of this oscillating signal is not related to the input bias voltage of the PCSS, the pulsecircuit components, or the electrode structure of the PCSS, rather it is related to the output characteristic of the PCSS.This physical phenomenon can be explained using the current surge model in photoconducting antenna. Preparingohmic contact electrode on the silicon carbide material forms the PCSS, which generates a large number ofphotogenerated carriers when ultra-fast laser pulses irradiate the surface of the material and Simultaneously applies abias voltage signal between the electrode. At this time inside the PCSS the electric field causes the transient current,radiating electromagnetic wave to the metal coil to generate oscillating signal.展开更多
认知无线电中频谱感知方法的性能与感知场景高度相关.研究表明,NakagamiGamma(KG)衰落信道模型能够可靠地描述无线通信信道.针对采样点数、接收信噪比、地理位置等多种性能影响因素各不相同的一组异构节点在KG衰落信道下的感知场景,提...认知无线电中频谱感知方法的性能与感知场景高度相关.研究表明,NakagamiGamma(KG)衰落信道模型能够可靠地描述无线通信信道.针对采样点数、接收信噪比、地理位置等多种性能影响因素各不相同的一组异构节点在KG衰落信道下的感知场景,提出了一种基于熵函数(based on entropy function,BEF)的合作感知方法.首先,根据异构节点的不同性能影响因素,通过定义的熵函数计算各节点的综合评价得分;然后,筛选出得分较高的节点进行标准化能量检测;最后,采用逻辑或(OR)准则进行融合判决.仿真结果表明,BEF方法有效地降低了系统的感知开销,在各个节点的目标虚警概率较低(Pf<0.1)时,显著提升了全局检测概率.展开更多
基金supported by Major Projects of Shanxi Province (202101030201001)。
文摘Constructing a photoconductive semiconductor switch (PCSS)-metal coil structure, we discovered anew phenomenon of electromagnetic oscillation in vanadium-compensation semi-insulating (VCSI) PCSS. Here thePCSS responds to laser pulse and high-voltage signal while the metal coil generates an oscillating voltage pulseenvelope signal. The generation of this oscillating signal is not related to the input bias voltage of the PCSS, the pulsecircuit components, or the electrode structure of the PCSS, rather it is related to the output characteristic of the PCSS.This physical phenomenon can be explained using the current surge model in photoconducting antenna. Preparingohmic contact electrode on the silicon carbide material forms the PCSS, which generates a large number ofphotogenerated carriers when ultra-fast laser pulses irradiate the surface of the material and Simultaneously applies abias voltage signal between the electrode. At this time inside the PCSS the electric field causes the transient current,radiating electromagnetic wave to the metal coil to generate oscillating signal.
文摘认知无线电中频谱感知方法的性能与感知场景高度相关.研究表明,NakagamiGamma(KG)衰落信道模型能够可靠地描述无线通信信道.针对采样点数、接收信噪比、地理位置等多种性能影响因素各不相同的一组异构节点在KG衰落信道下的感知场景,提出了一种基于熵函数(based on entropy function,BEF)的合作感知方法.首先,根据异构节点的不同性能影响因素,通过定义的熵函数计算各节点的综合评价得分;然后,筛选出得分较高的节点进行标准化能量检测;最后,采用逻辑或(OR)准则进行融合判决.仿真结果表明,BEF方法有效地降低了系统的感知开销,在各个节点的目标虚警概率较低(Pf<0.1)时,显著提升了全局检测概率.
