|
Thesis
/ | ROMDOC-THESIS-2017-1006 |
Modele de câmp şi de circuit pentru rezonatoare de putere cu unde acustice de volum
Florea, Aurelian
2011-10-10
Abstract: Field and Circuit Model in Power BAW Resonators The AlN bulk acoustic wave (BAW) technology emerged in the last several years as an efficient solution for communication filters, due to its low price and compatibility with CMOS technology. The behavior of AlN resonators at high power levels is defined by the amplitude-frequency effect and the intermodulation effect. If the resonator is driven by a sinusoidal signal with frequency f, the first effect consists in the decreasing of the series and parallel resonance frequencies as the incident power increases, while the second one is given by the 2f and 3f harmonic components in the reflected power. Both behavioral and physical circuit models of the power BAW resonators have been developed in this thesis; these models reproduce, for the first time, the amplitude-frequency effect and the frequency dependence of the 2f component in the reflected power. The experimental results measured at LAAS Toulouse using two sets of resonators produced by CEA-LETI Grenoble are presented. The parameters of two behavioral models have been identified taking into account the influence of the connection wires. A good agreement between simulations and measurements has been obtained except some undulations in the frequency characteristic of the 2f component in the reflected power. Being simple nonlinear circuits with polynomial nonlinearities these models are very efficient for simulation of systems containing filters build with BAW resonators. Two physical models (whose parameters have an explicit dependence on the material parameters) have been developed. These models are nonlinear artificial lines corresponding to a mechanical or an electrical nonlinearity. Polynomial nonlinearities of the second order have been considered in both cases. For the mechanical nonlinearity the coefficients of this polynomial can be fitted to reproduce both measured amplitude-frequency effect and the frequency characteristic of the 2f component in the reflected power. For the electrical nonlinearity this fitting cannot be made. It follows that the mechanical nonlinearity is a more probable origin of the nonlinear behavior of a power BAW AlN resonator than the electrical nonlinearity. A significant reduction of the 2f component in the reflected power of an anti-parallel connection of two resonators (in comparison with the parallel connection of the same resonators) has been measured and reported for the first time. This result confirms the use of the anti-series and the anti-parallel connections to reduce the 2f components in filters build by companies like INFINEON and EPCOS. A simplified linear 3D electromechanical field model has been used in order to identify the parameters of various materials used in building a solidly mounted resonator structure. A complete linear 3D lossless field model has been implemented in ANSYS, while the Rayleigh loss coefficients of a linear 3D model have been identified using the COMSOL simulator.
Keyword(s): Rezonatoare de putere -- Proiectare -- Teză de doctorat ; Dispozitive electromecanice -- Proiectare -- Teză de doctorat ; Rezonatoare piezoelectrice -- Teză de doctorat
OPAC: See record in BC-UPB Web OPAC
Full Text: see files
Record created 2017-02-24, last modified 2017-02-24
Similar records
| People who viewed this page also viewed: |
|
|
Be the first to review this document.
Start a discussion about any aspect of this document.
guest ::