: Modeling and characterization strategies were developed to capture the complex nonlinear behavior of both the components within an RF circuit and within an assembled system Metrology techniques using common laboratory instrumentation were developed for the remote characterization of assembled RF devices and the result of this characterization is presented here for the first time In addition, two novel intermodulation relative phase measurement systems were developed that have 90 dB of dynamic range which is a considerable improvement over existing systems This enables the measurement of weaker nonlinearities and increases the accuracy of these measurements A behavioral modeling architecture and extraction procedure were developed to take advantage of the metrology techniques to allow the separation of odd-ordered nonlinear effects and baseband upconversion effects in several amplifiers The results of applying this modeling strategy has produced a general model capable of predicting both magnitude and phase asymmetries in nonlinear components for the first time Concepts from the remote characterization, intermodulation phase measurement systems, and the modeling efforts were combined to demonstrate the extraction of two-port transmission parameters from one-port measurements in an archetypal circuit of an integrated bandpass filter in an RF front-end It is shown how this information can be used to tune a filter

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Behavioral Modeling and Characterization of Nonlinear Operation in RF and Microwave Systems

The impedance of atmospheric pressure argon plasma jets driven by microwave frequency is determined in situ by a novel 'two frequency method'. In the conventional method of reflection coefficient measurement, the frequency of the driving microwave power is scanned, which inevitably affects the plasma characters and leads to uncertainty in the estimated plasma impedance. In our proposed method, the frequency-scanning signal additional to the driving power is used to measure over a wide frequency range, which enables accurate determination of the plasma impedance based on an equivalent circuit model. The measured resistance and reactance of the plasma increase with the driving power in agreement with the transmission line theory. Based on this in situ measurement of the plasma impedance, the net power coupled to the plasma has been determined. The overall power efficiency remains approximately unchanged around 45% for different input power levels owing to the competing effects between the impedance mismatch and the volume change of the plasma.

https://iopscience.iop.org/article/10.1088/1361-6595/aa5d26/pdf

In situ impedance measurement of microwave atmospheric pressure plasma

This paper discusses necessity of power-waves formulation to extend voltage-current oriented approaches based on linear concepts such as admittance/impedance operators and transfer-function representations. Importance of multi-physics methodologies, throughout power-waves formulation, for the analysis and design of crystal oscillators is discussed. Interpretation of bifurcation modes in differential cross-coupled VCO architectures in terms of gyrator-like behavior, is proposed. Impact of amplitude level control (ALC) on large-signal phase noise performances is underlined showing necessity of robust control analysis approach relative to power-energy considerations.

Power waves formulation of oscillation conditions: Avoidance of bifurcation modes in cross-coupled VCO architectures

Range finding in passive wireless sensor networks using power-optimized waveforms

Les auteurs proposent une definition rigoureuse des parametres P en regime de fort signal, non lineaires, permettant de caracteriser un multipole actif en vue de son utilisation dans la conception assistee par ordinateur de dispositifs microondes de puissance. Ces parametres doivent d’une part pouvoir dependre de toutes les variables d’entree aux acces du circuit et d’autre part se comporter comme les parametres caracterisant le circuit en regime lineaire lorsque les amplitudes de ces variables tendent vers zero. Une application simple de cette definition est donnee pour un transistor a effet de champ.

Définition théorique des paramètres en fort niveau d’un multipôle actif non linéaire

At microwaves, it is necessary to define rigorously the large signal reflection coefficient of a nonlinear device. In this paper, the describing function concept is applied to the power waves incident on, and reflected by, a nonlinear element. This method allows us to define the nonlinear reflection coefficient (NLRC) on the power wave basis. This NRLC is then compared with that defined on the current or voltage basis. Numerical calculations applied to nonlinear elements illustrate the theoretical results.

F. Farzaneh

Papers

Definition of Nonlinear Reflection Coefficient of a Microwave Device Using Describing Function Formalism (Short Paper)