Block oriented model order reduction of interconnected systems

SUMMARY Unintended and parasitic coupling effects are becoming more relevant in currently designed, small-scale/high-frequency RFICs. Electromagnetic (EM) based procedures must be used to generate accurate models for proper verification of system behaviour. But these EM methodologies may take advantage of structural subsystem organization as well as information inherent to the IC physical layout, to improve their efficiency. Model order reduction techniques, required for fast and accurate evaluation and simulation of such models, must address and may benefit from the provided hierarchical information. System-based interconnection techniques can handle some of these situations, but suffer from some drawbacks when applied to complete EM models. We will present an alternative methodology, based on similar principles, that overcomes the limitations of such approaches. The procedure, based on structure-preserving model order reduction techniques, is proved to be a generalization of the interconnected system based framework. Further improvements that allow a trade off between global error and block size, and thus allow a better control on the reduction, will be also presented.