A New Technique for the Direct Measurement of Y-Parameters at Microwave Frequencies
A technique has been developed which makes practical the direct measurement of active device two-port y-parameters at microwave frequencies. The instrumentation involved is a simple modification of a conventional s-parameter test set, and the measurement procedure is only slightly more complicated than in a conventional s parameter measurement.
Method of optimum oscillator design using power-dependent S-parameters
A graphical approach is described for the optimum design of microwave FET oscillators. By use of nonlinear FET S-parameters, defined as functions of the output power, the input and output powers are represented by distorted paraboloids of revolution. Using these newly defined nonlinear S-parameters, the design procedure for microwave FET oscillators is illustrated, based on the paraboloids.
Monte Carlo simulations of magnetovolume instabilities in anti-Invar systems
We perform constant pressure Monte Carlo simulations of a spin-analogous model which describes coupled spatial and magnetic degrees of freedom on an fcc lattice. Our calculations qualitatively reproduce magnetovolume effects observed in some rare earth manganese compounds, especially in the anti-Invar material YMn2. These are a sudden collapse of the magnetic moment which is connected with a huge volume change, and a largely enhanced thermal expansion coefficient.