排序方式: 共有17条查询结果,搜索用时 0 毫秒
1.
2.
Electrodynamic Analysis of Dissipative Electromagnetic Materials Based on Fractional Derivative 下载免费PDF全文
The generalized Lagrangian is defined in a dissipative electromagnetic medium on the basis of the combination of dynamical analysis and fractional derivative. Lorentz medium models are obtained by formulating relevant Euler-Lagrange equations. The invariance is obtained subsequently by investigating the invariance of time variation in the system, and then the relation between the related Hamiltonian and electromagnetic energy density is investigated. Canonical equations are obtained eventually. The electrodynamic interpretation on dissipative electromagnetic systems is revealed. 相似文献
3.
4.
Based on Fermat's principle and the special relativity, the transmission of high-frequency electromagnetics is unified by variational formulation on the moving interface. Applying the theoretical model, we investigate the detailed practices of transmission of high-frequency electromagnetic under relativistic conditions. The deduced results illustrate that the effective estimation of the super high-speed effect on a moving interface supports the valuable frame of reference in controlling precision. The results also show that the theoretical model has potential applications in electromagnetically controlled precision in the quantum information, ray sensor, controllable environment, etc. 相似文献
5.
漏缆传感器的入侵探测定位系统已广泛应用于国防设施、银行、监狱等重要区域,为提高这种系统的定位精度,提出了一种基于脉冲压缩的漏缆传感器探测定位新方法。该方法将巴克码调制的二进制相移键控信号引入系统作为发射信号,并对接收信号进行滤波相减、相干解调、抽样判决和自相关运算等一系列信号处理,以获得含有入侵位置信息的特征信号。应用MATLAB 和电磁仿真软件CST 对该系统进行了协同仿真分析,并搭建了实验系统进行测试。仿真结果与实测结果吻合良好,验证了新方法探测定位的有效性。新方法的定位精度约为0.9 m,优于目前已报道的同类探测定位系统的定位精度。 相似文献
6.
7.
8.
9.
10.
针对卫星通信中5G天线安装空间和结构尺寸存在限制的问题,文中基于梯形振子结构和L形弯折方式实现了星载5G天线的小型化设计。通过将对数周期天线的振子由矩形转变为长度更短的梯形,采用两个梯形结合1个90°扇形结构进一步合成该天线,优化振子结构,实现天线尺寸的横向缩减和小型化设计。文中将所设计天线应用于某型卫星平台中,研究不同摆放位置下的天线耦合度。结果表明,相较于传统结构,该小型化LPDA的横向尺寸从90 mm缩小到了65 mm,拥有更好的端口阻抗匹配特性和辐射性能,可以较好地满足5G卫星通信中载荷紧凑化、轻量化和频带集约化的应用要求。 相似文献