Abstract: Aspects of this disclosure relate to acoustic wave filters with second harmonic emission suppression. In an embodiment, an acoustic wave filter includes a first bulk acoustic wave resonator, a second bulk acoustic wave resonator in anti-parallel with the first bulk acoustic wave resonator, and a passive impedance element in series with the first bulk acoustic wave resonator. The passive impedance element can reduce an imbalance in resonant frequency between the first and second bulk acoustic wave resonators. Other embodiments of acoustic wave filters with second harmonic emission suppression are disclosed. Related multiplexers, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: Aspects of this disclosure relate to acoustic wave filters with second harmonic emission suppression. In an embodiment, an acoustic wave filter includes a first pair of bulk acoustic wave resonators in anti-series with each other, a second pair of bulk acoustic wave resonators in anti-series with each other and having reverse electrode polarization relative to the first pair of bulk acoustic wave resonators, and a capacitor connected to a common electrode of a first bulk acoustic wave resonator and a second bulk acoustic wave resonator of the first pair of bulk acoustic wave resonators. Such an acoustic wave filter can provide second harmonic emission suppression. Other embodiments of acoustic wave filters with second harmonic emission suppression are disclosed. Related multiplexers, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: Aspects of this disclosure relate to acoustic wave filters with second harmonic emission suppression. In an embodiment, an acoustic wave filter includes a first pair of bulk acoustic wave resonators in anti-series with each other and a second pair of bulk acoustic wave resonators in anti-series with each other. The second pair of bulk acoustic wave resonators has reverse electrode polarization relative to the first pair of bulk acoustic wave resonators. The first pair of bulk acoustic wave resonators is in series with the second pair of bulk acoustic wave resonators. Other embodiments of acoustic wave filters with second harmonic emission suppression are disclosed. Related multiplexers, radio frequency modules, wireless communication devices, and methods are disclosed.

Abstract: A method for improving the accuracy of a final inspection (FI) test of an acoustic wave device includes gating the feedthrough/cross-coupling (e.g., electromagnetic (EM) path) signal of the FI test data response for the tested acoustic wave device and adding a feedthrough/cross-coupling signal (e.g., EM path signal) from an engineering (EVB) test data (e.g., for a similar or identical surface acoustic device). This results in FI test data with time domain recovery of EM path signal from an EVB test, which can be compared against EVB test data (e.g. for a similar or identical surface acoustic device) to determine if the tested acoustic wave device passes inspection.