The state and output equations of the overall networks are derived from the state and output equations of individual multiports and knowledge of the interconnections between them. A generalized lumped-distributed L/D multiport is described by its associated state, output and non-linear equations in the time domain. Any network can be considered as composed of a set of multiports and independent sources. These equations have been incorporated into a computer-aided procedure for the analysis of L/D networks. The procedure can be used for the simulation of any non-linear microwave circuit and offers the facility of developing a multiport equivalent circuit for any linear or non-linear device or subcircuit. Several examples are successfully analysed using the developed general program.

Multiport approach for the analysis of microwave non-linear networks

The state and output equations of the overall networks are derived from the state and output equations of individual multiports and knowledge of the interconnections between them. A generalized lumped-distributed (L/D) multiport is described by its associated state, output, and nonlinear equations in the time domain. Any network can be considered as composed of a set of multiports and independent sources. A computer-aided procedure for the analysis of L/D networks is discussed. The procedure can be used for the simulation of any nonlinear microwave circuit and offers the facility of developing a multiport equivalent circuit for any linear or nonlinear device or subcircuit. An example analysis is presented. >

Computer-aided analysis of non-linear lumped-distributed multiport networks

This paper will report on the use of state-space (time varying) variables to anaylze and design microwave ICs, including not only linear passive and active elements, but nonlinear and time-varying elements.

Computer-aided design of nonlinear microwave ICs

In this paper we illustrate the use of a state space approach for the analysis of left-handed transmission lines, where an RLC equivalent circuit model is used to represent the transmission line. Steady state S-parameter frequency responses can be obtained directly from the state matrices, whereas the temporal response for arbitrary input excitations requires solution of the state equation. Validation using conventional methods is demonstrated.

State-space analysis of left-handed transmission lines

The authors describe the extension of the state space technique to analysis of nonlinear and time-variant lumped/distributed (L/D) networks. The topological formulation of state, output, and nonlinear equations for nonlinear and time-variant networks containing multiports and independent sources is used. These equations have been incorporated into a computer-aided procedure for the analysis of L/D networks. The procedure can be used for the simulation of any nonlinear microwave circuit and offers the facility of developing a multiport equivalent circuit for any linear or nonlinear device or subcircuit. Several examples are successfully analyzed using the developed general program. Practical microstrip circuits of the above-mentioned nonlinear circuit are given, and experimental and simulated results show very good agreement. >

Computer aided analysis and design of nonlinear multiport microstrip networks in frequency and time domain

Lumped/distributed networks are analysed using state-space techniques. The state and output equations are derived using topological methods with no restrictions on the topology. The method is applied to noncommensurate circuits and to coupled transmission-line circuits in inhomogeneous media. Computer programs have been developed for the analysis of these circuits in both the frequency and time domains. The time response, for any set of inputs, is obtained without the need of either the explicit form of the transfer function or the use of convolution.

M.I. Sobhy

Papers

State-space analysis of lumped/distributed networks in time and frequency domains