Analyzing the 2nd Harmonic Emissions of a BAW Resonator Undergoing Lateral Mode Excitation

For the first time of which we are aware, high frequency resolution phase and magnitude measurements of the 2nd harmonic (H2) emissions response of a BAW resonator are recorded and analyzed. A circular resonator exhibiting distinct lateral modes and H2 emissions rattles is analyzed in a variety of ways: First using a nonlinear extended BVD model to relate both the phase and magnitude of H2 emissions to its linear S11 response, then via an analytical model of H2 emissions, and finally via a nonlinear 2D FEM model. The H2 phasor emissions of a resonator having a practical shape, and thus exhibiting complex lateral mode and H2 rattle behavior is measured. A measurement-based H2 model is constructed, and then is used to model the H2 emissions response of an anti-series resonator pair.