In the spatial network method (SNM) for the vector potential, both the current continuity law including polarization vector and the conservation law of generalized momentum including vector potential field can introduce simpler expressions for dispersive property than that by the electromagnetic field variables. But for the anisotropic medium conditions, the conventional expanded node expression has some difficulties in treating the coupling mechanism among field variables. On the other hand, in the condensed node expression, in which all field components exist at each node, every connections among field components can be simply formulated. In this paper, after proposing the condensed node spatial network method for the vector potential, the advantage of the method such as performing the simplified formulation by utilization of both the vector potential and the condensed node expressions is presented for the magnetized plasma which has the gyro-anisotropy. The validity of the computation is shown by some examples such as Faraday rotation.

Coupling in time domain between two non-parallel transmission lines of finite length is analyzed by using a circuit concept. Coupling equations based on the Maxwell's equations for lossless transmission lines in a homogeneous medium are written by a set of non-homogeneous differential equations including distributed source terms produced by external electromagnetic fields. The forcing terms are expressed by vector potentials generated by currents in the line section and at the transitions. A set of solutions in frequency domain is obtained by a four-port network expression with regard to the terminal voltages and currents, and can be applied to estimation of the frequency-domain crosstalk. Utilizing the inverse fast Fourier transform (FFT), the crosstalk responses between the lines is studied in time domain. Comparison of theoretical and experimental results shows the validity of the method.