Roland Neumayer

On the synthesis of equivalent circuit models for multiports characterized by frequency-dependent parameters

The synthesis of lumped-element equivalent circuits for time-domain analysis of problems with frequency-dependent parameters is of great interest in microwave theory. This paper presents a systematic approach to generate minimal order realizations for passive microwave circuits characterized by either admittance, impedance or scattering parameter data. Also a very efficient method to ensure inherent system properties such as stability and passivity is described. Modeling examples for a two- and four-port system are given.

On the synthesis of equivalent-circuit models for multiports characterized by frequency-dependent parameters

The synthesis of lumped-element equivalent circuits for time-domain analysis of problems with frequency-dependent parameters is of great interest in microwave theory. This paper presents a systematic approach to generate minimal order realizations for passive microwave circuits characterized by either admittance, impedance or scattering parameter data. Also a very efficient method to ensure inherent system properties such as stability and passivity is described. Modeling examples for a two- and four-port system are given.

Synthesis of SPICE-compatible broadband electrical models from n-port scattering parameter data

In this paper, an efficient technique for the synthesis of broadband electrical models from multiport scattering parameter data (S-parameter) is presented. A curve fitting algorithm is applied to either measured or simulated S-parameters to generate a frequency-dependent transfer-function matrix representation of the system of interest. By means of macromodel synthesis techniques an equivalent circuit network, consisting of standard circuit elements, is derived from the transfer-function matrix representation. The synthesized networks are compatible with SPICE-based circuit simulators, as demonstrated by numerical examples for a two-port and a four-port system. The proposed method is suitable for the analysis of S-parameter based linear sub-networks in a general circuit environment consisting of lumped/distributed elements and nonlinear devices.

Continuous simulation of system-level automotive EMC problems

Electromagnetic compatibility (EMC) issues are increasingly important to the automotive industry. Potential EMC problems arise from the growing use of electronic systems on the one hand and the lack of flexibility in placement or design of electronic modules on the other hand. In this paper we present a continuous EMC simulation process based on the exchange of EMC models between car manufacturer, electronic supplier and IC developer as applied to a general automotive application. The described process fundamentally influences the introduction of new technologies in automobiles by cutting the risk of EMC-failure and avoiding expensive and time-consuming redesigns.

Equivalent circuit modeling using frequency-domain subspace system identification

This paper addresses the generation of equivalent circuit models from frequency-dependent network parameters. In particular, a recently developed frequency-domain subspace identification algorithm is applied to generate SPICE-based multiport models of complex electrical structures or components characterized by admittance, impedance, or scattering parameter data. The extracted non-parametric minimal order realization enables efficient EMC analysis in general circuit environment, as is demonstrated by a practical example. Kevwords: Equivalent Circuits, Modeling, Frequency Domain Synthesis, Multiport Circuits, Passive Circuits, Reduced Order Systems.

Identification of microwave device and packaging models from frequency response data

As system integration evolves and package densities increases, it becomes increasingly important to model non-ideal behavior of previously neglected frequency-domain effects of the microwave components and packaging interconnects. This paper addresses the generation of SPICE-based circuit models from frequency-domain response parameters. In particular, a recently developed subspace identification algorithm is applied to generate passive multi-port models of microwave devices and packages characterized by measured or simulated network parameters. Results of the application of the proposed method applied to real-world examples are given.

A comparison of complex curve fitting and subspace identification algorithm for circuit modeling using frequency domain data

Efficient transient simulation of complex structures or components characterized by frequencydomain network parameters is of great interest in microwave theory. In this paper, two different model extraction techniques for broadband linear network characterization are discussed. A parametric complex curve fitting technique and a frequency-domain subspace identification algorithm are applied to generate passive circuit models for microwave devices characterized by measured frequency-domain port response data. By means of practical examples both methods are evaluated regarding usability, accuracy and CPU time.

Challenges in Automotive Electromagnetic Compatibility Modeling and Simulation

Electromagnetic compatibility (EMC) issues are increasingly important to the automotive industry. Problems arise from the growing use of electronic systems on the one hand and the lack of flexibility in placement or design of electronic modules on the other hand. Consequently, an accurate system-level EMC analysis is required from early stages of the vehicle design process. This paper presents a concurrent EMC simulation process that incorporates the EMC behavior of the electronic equipment in the system-level automotive EMC simulation. The proposed process helps to identify and reject potential EMC problems introduced by new technologies. This cuts the risk of EMC failure and avoids costly and time-consuming redesigns.