Conference Paper

Computation of a Subset of X-Parameters Using the Adjoint Method

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The polyharmonic distortion parameters of a nonlinear structure or circuit block, often referred to as X-parameters,* relate the different harmonics of the incident waves to those of the reflected waves in the frequency domain. Recently, a closed form derivative-based approach for calculating the X-parameters sensitivity with respect to linear circuit elements has been developed for a given input amplitude level. In this manuscript, we build on those results and present an efficient and accurate moments based method for the sensitivity analysis with respect to both linear and nonlinear circuit parameters, parameterized with respect to the input amplitude. The proposed method allows for the accurate and efficient computation of X-parameter sensitivity terms without the need for CPU expensive sweeps or brute force perturbation.
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This is the definitive guide to X-parameters, written by the original inventors and developers of this powerful new paradigm for nonlinear RF and microwave components and systems. Learn how to use X-parameters to overcome intricate problems in nonlinear RF and microwave engineering. The general theory behind X-parameters is carefully and intuitively introduced, and then simplified down to specific, practical cases, providing you with useful approximations that will greatly reduce the complexity of measuring, modeling and designing for nonlinear regimes of operation. Containing real-world case studies, definitions of standard symbols and notation, detailed derivations within the appendices, and exercises with solutions, this is the definitive stand-alone reference for researchers, engineers, scientists and students looking to remain on the cutting-edge of RF and microwave engineering.
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Contenido: 1) Conceptos fundamentales; 2) Redes de ecuaciones y su solución; 3) Formulación gráfica teórica de redes de ecuaciones; 4) Métodos generales de formulación; 5) Sensibilidades; 6) Generación por computadora de sensibilidades; 7) Funciones de redes en el dominio de frecuencia; 8) Cambios grandes de sensibilidad; 9) Introducción a la integración numérica de ecuaciones diferenciales; 10) Inversión numérica de la transformación de Laplace; 11) Modelado; 12) Solución DC de redes; 13) Integración numérica ecuaciones diferenciales y algebraicas-diferenciales; 14) Redes digitales y capacitares conmutados; 15) Introducción a la teoría de la optimización; 16) Dominio temporal de la sensibilidad y estado constante; 17) Diseño por minimización.
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