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The current-voltage characteristics of microwave-irradiated superconducting weak links have been calculated on the analog computer. Experimental results of several authors can be interpreted correctly by taking into consideration the resistive feedback.

For phased array receivers, mutual coupling leads to beam-dependent effective impedances at array element ports. Front end amplifiers can be matched for optimal noise performance for one beam steering direction, but noise performance becomes poor at other steering directions. We analyze this noise penalty in terms of beam equivalent noise temperature for various amplifier noise matching conditions, and develop a new matching condition that minimizes the average beam equivalent receiver noise temperature over multiple beams. For nonbeamforming applications such as MIMO communications, we show that noise performance for coupled arrays can be quantified using the spectrum of an available receiver noise temperature correlation matrix.

We reformulate the existing auxiliary differential equation (ADE) technique in the context of the finite-difference time-domain analysis of Maxwell's equations for the modeling of optical pulse propagation in linear Lorentz and nonlinear Kerr and Raman media. Our formulation is based on the polarization terms and allows simple and consistent implementation of such media together with the anisotropic perfectly matched layer (APML) absorbing boundary condition. The disadvantages of the ADE technique, i.e., requiring additional storage for auxiliary variables, has been overcome by adopting the high-order finite-difference schemes derived from the previously reported wavelet-based formulation. With those techniques, we demonstrate in two-dimensional setting an effective and accurate numerical analysis of the spatio-temporal soliton propagation as a consequence of the physically originated balanced phenomena between the self-focusing effect of nonlinearity and the pulse broadening effects of the temporal dispersion and of the spatial diffraction.

In this paper, an efficient method for the numerical simulation of near-and far-field propagation of stochastic electromagnetic (EM) fields is presented. The method is based on the transformation of field correlation dyadics using Green's functions or the field transfer functions computed for deterministic fields. The method accounts for arbitrary correlations between the noise radiation sources and allows to compute the spatial distribution of the spectral energy density of noisy electromagnetic sources. The introduced methodology can be combined with available electromagnetic modeling tools. It is shown that the method of moments can be applied to solve noisy electromagnetic field problems by network methods applying correlation matrix techniques. Examples demonstrating the strong influence of the correlation between the sources on the spatial distribution of the radiated noise field are presented.Index Terms-Electromagnetic interference, near-field scanning, noisy electromagnetic fields, stochastic electromagnetic fields. 0018-9480