X-Parameter Measurement and Simulation of a GSM Handset Amplifier
01 Oct 2008-pp 135-138
TL;DR: In this paper, a new approach to X-parameter characterization and nonlinear simulation, including large-signal experimental model validation, of a commercially available GSM amplifier is described.
Abstract: X-parameters, also referred to as the parameters of the Poly-Harmonic Distortion (PHD) nonlinear behavioral model, have been introduced as the natural extension of S-parameters to nonlinear devices under large-signal drive [1]-[3]. This paper describes a new approach to X-parameter characterization and nonlinear simulation - including large-signal experimental model validation - of a commercially available GSM amplifier. A specially configured Nonlinear Vector Network Analyzer (NVNA) and procedure for measuring, for the first time, X-parameters under pulsed bias conditions is presented. The measured pulsed bias X-parameters are then used with the PHD framework to enable accurate nonlinear simulation of device behavior, including harmonics (magnitude and phase) under pulsed bias large-signal conditions with mismatch. Independent NVNA measurements validate the predictions of the X-parameter simulations of output match under drive, and show the inadequacy of "Hot S22" techniques to predict such device performance.
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26 Sep 2013TL;DR: 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, providing useful approximations that will greatly reduce the complexity of measuring, modeling and designing for non linear regimes of operation.
Abstract: 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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72 citations
TL;DR: In this paper, a monolithic microwave integrated circuit Doherty power amplifier (DPA) operating at sub-6 GHz for 5G communication applications by a 0.25-μm gallium nitride high-electron mobility transistor process is presented.
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48 citations
Cites background from "X-Parameter Measurement and Simulat..."
...and harmonic mixing under large-signal operation [24], [25]....
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01 Jun 2017
TL;DR: In this article, a method to optimize the IC placement in mobile devices from RF interference perspective is proposed, where the coupling from the IC to an antenna is estimated by combining the equivalent dipole moment source and reciprocity, which facilitates understanding of coupling physics and design insight for the mobile devices.
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25 citations
17 May 2015
TL;DR: In this article, a measurement setup has been developed by extending a nonlinear vector network analyzer with required external components enabling X-parameter measurements at high power levels for the first time the Polyharmonic distortion (PHD) model has been used to characterize the nonlinearities of bulk acoustic wave (BAW) components.
Abstract: For the first time the Polyharmonic Distortion (PHD) model has been used to characterize the nonlinearities of Bulk Acoustic Wave (BAW) components. For that purpose a measurement setup has been developed by extending a nonlinear vector network analyzer with required external components enabling X-parameter measurements at high power levels. By discussion of selected components of the BAW resonator's PHD model and performing simulations in an RF design environment the importance of PHD model for improved BAW filter design has been demonstrated.
17 citations
References
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TL;DR: The PHD model as discussed by the authors is a black-box frequency-domain model that provides a foundation for measurement, modeling, and simulation of driven nonlinear systems, including compression, AM-PM, harmonics, load-pull, and timedomain waveforms.
Abstract: For more than a quarter of a century, microwave engineers have had the benefit of a foundation of mutually interacting components of measurement, modeling, and simulation to design and test linear components and systems. S-parameters are perhaps the most successful behavioral models ever. They have the powerful property that the S-parameters of individual components are sufficient to determine the S-parameters of any combination of those components. S-parameters of a component are sufficient to predict its response to any signal, provided only that the signal is of sufficiently small amplitude. We have presented the PHD modeling approach. It is a black-box frequency-domain model that provides a foundation for measurement, modeling, and simulation of driven nonlinear systems. The PHD model is very accurate for a wide variety of nonlinear characteristics, including compression, AM-PM, harmonics, load-pull, and time-domain waveforms. The PHD model faithfully represents driven nonlinear systems with mismatches at both the fundamental and harmonics. This enables the accurate simulation of distortion through cascaded chains of nonlinear components, thus providing key new design verification capabilities for RF and microwave modules and subsystems
359 citations
07 Nov 2005
TL;DR: The derived model is valid for both small and large amplitude drive signals, correctly predicts even and odd harmonics through cascaded chains of functional blocks, simulates accurately load-pull behavior away from 50 /spl Omega/, and predicts adjacent channel power ratio and constellation diagrams in remarkably close agreement to the circuit model from which the behavioral model was derived.
Abstract: We present an optimal experiment design methodology and a superior and fully automated model generation procedure for identifying a class of broad-band multiharmonic behavioral models in the frequency domain. The approach reduces the number of nonlinear measurements needed, minimizes the time to generate the data from simulations, reduces the time to extract the model functions from data, and when used for simulation-based models, takes maximum advantage of specialized simulation algorithms. The models have been subject to extensive validation in applications to real microwave integrated circuits. The derived model is valid for both small and large amplitude drive signals, correctly predicts even and odd harmonics through cascaded chains of functional blocks, simulates accurately load-pull behavior away from 50 /spl Omega/, and predicts adjacent channel power ratio and constellation diagrams in remarkably close agreement to the circuit model from which the behavioral model was derived. The model and excitation design templates for generating them from simulations are implemented in Agilent Technologies' Advanced Design System.
219 citations
03 Jun 2007
TL;DR: In this paper, the PHD nonlinear behavioral model is extended to handle multiple large tones at an arbitrary number of ports, and enhanced for dynamic long-term memory for HBT amplifiers.
Abstract: The PHD nonlinear behavioral model is extended to handle multiple large tones at an arbitrary number of ports, and enhanced for dynamic long-term memory. New capabilities are exemplified by an amplifier model, derived from large-signal network analyzer (LSNA) data, valid for arbitrary impedance environments, and a model of a 50GHz integrated mixer, including leakage terms and IF mismatch dependence. Dynamic memory is demonstrated by an HBT amplifier model identified from up-converted band-limited noise excitations. The models are validated with independent LSNA component data or, for simulation-based models, with the corresponding circuit models.
60 citations
12 Jun 2005
TL;DR: In this article, the same harmonic balance or envelope transient simulation engine is used for both transistor level description and circuit block macro-models to reduce the size of the problem to enable accurate and fast simulation of large size circuits.
Abstract: The development of simulation and macro-modeling techniques for RF and microwave communication systems has been a high priority research subject for several years. If one observed this last years an impressive improvement of simulation tools performances, the full chip simulation of modern TX-RX chains remains a real stumbling block, as the transistor count has considerably increased. This paper discusses the hierarchical RF simulation issue using the same harmonic balance or envelope transient simulation engine for both transistor level description and circuit block macro-models. This method can reduce the size of the problem to enable accurate and fast simulation of large size circuits. The concept requires however to develop macro-modeling techniques taking into account impedance mismatch effects, which are discussed here.
34 citations