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An efficient time domain hybrid method is proposed, which integrate transmission line (TL) equations, finite‐difference time‐domain (FDTD) method, Norton and Substitution theorems together, to predict the EM fields coupling with the penetrated wire connecting two electronic devices. Within this method, the geometry of penetrated wire is divided into external and internal TLs according to the shielded enclosures of two devices firstly. Then the equivalent circuit model of penetrated wire is established by the Norton and Substitution theorems, which can represent the discontinuity of impedance between external and internal TLs and the transmitting of interference signals between terminal loads of the wire. Finally, the TL equations combined with FDTD method is utilized to compute the transient responses on external and internal TLs respectively. Numerical simulations of penetrated wire connecting two shielded enclosures in different environment are employed to verify the accuracy and efficiency of the presented method. [ABSTRACT FROM AUTHOR]

Due to the shielding structures of electronic system and coaxial lines feeding the antennas are complex, full‐wave algorithms applied for the coupling analysis of multiple linear antennas on electronic system excited by ambient wave should occupy amount of memories by meshing the structures of coaxial lines and electronic system in fine grid, which may affect the computation efficiency. This paper presents a time domain hybrid method, which consisting of thin wire finite‐difference time domain (FDTD) method, transmission line (TL) equations, higher order FDTD scheme, and an auto mesh generator technique. In this method, the thin wire FDTD combined with the auto mesh generator technique is utilized to mesh the shielding structure of electronic system rapidly and obtain the current responses on the conductor columns of linear antennas, which are extracted equivalent current sources for the further coupling analysis of coaxial lines. And then the TL equations are adopted to build the coupling models of coaxial lines, and solved by the higher order FDTD scheme to compute the transient responses on the coaxial lines and terminal loads of the lines. This method has one significant feature is that it can avoid modeling the structures of linear antennas and coaxial lines directly. The accuracy of this method has been verified by comparing with the simulation software Computer Simulation Technology (CST) via the coupling simulations of one and three linear antennas on electronic system excited by ambient plane wave. [ABSTRACT FROM AUTHOR]

To efficiently solve the coupling problems of two wires above the ground excited by incident electromagnetic pulses, a time domain hybrid method consisting of transmission line (TL) equations, finite difference time domain (FDTD) method, and a fast calculation approach to the excitation fields of the wires is presented. In this hybrid method, a novel coupling model of the two wires is established by the TL equations firstly, which is suitable for arbitrary heights of the two wires and for considering influences of the ground on distributed parameters of the two wires. Then, due to the obviously infinite dimension of the ground, a fast calculation approach is utilized to obtain the excitation fields of the wires to avoid modeling the ground directly. Finally, the FDTD method is adopted to discretize the TL equations to calculate the transient responses at the termination loads of the two wires. Numerical examples are given to demonstrate the accuracy and efficiency of this hybrid method. It shows that this method can tremendously decrease the memory requirement and computation time, compared with the full‐wave method. The applicability of this method in fast coupling analysis of long two wires with arbitrary heights above the ground excited by multiple electromagnetic pulses is verified. [ABSTRACT FROM AUTHOR]

Due to the numerical methods used for the coupling analysis of the shielded cavity with penetrated wire excited by ambient wave are lack, an efficient time domain hybrid method is presented in this article, which consists of thin wire finite difference time domain (FDTD) method and hybrid FDTD and transmission line equations method (called FDTD‐TL method). In this method, the penetrated wire is decomposed into external and internal transmission lines according to the enclosure structure of the shielded cavity firstly. Then the thin wire FDTD method is applied to calculate the currents on the external transmission line, which are enforced as the boundary of the internal transmission line naturally. Meanwhile the FDTD‐TL method is used to build the coupling model of ambient wave to the internal transmission line to obtain the voltage and current responses on the terminal load of internal line. This method has one prominent advantage is that it can realize the cooperative calculations of electromagnetic field radiation and the coupling responses on the penetrated wire. Finally, two numerical simulations of ambient wave to one shielded cavity with penetrated wire in the free space and shielded cavity are utilized to verify the accuracy and efficiency of this presented method by comparing with the electromagnetic software CST. [ABSTRACT FROM AUTHOR]