Abstract:
A switchable filter may include a first acoustic resonator including first electrodes, and a first resonant layer between the first electrodes and having electrostrictive material. The switchable filter may further include a second acoustic resonator including second electrodes, and a second resonant layer between the second electrodes and having electrostrictive material. The second acoustic resonator may be acoustically coupled with the first acoustic resonator. At least one of the first electrodes and at least one of the second electrodes may be arranged between the first resonant layer and the second resonant layer. The electrostrictive material may adjust a resonance and a filter switching of the first and second acoustic resonators as a function of a control voltage applied to terminals of the first and second acoustic resonators. Two electrodes from one of the first electrodes and the second electrodes may be filter input electrodes. Two electrodes from one of the first electrodes and the second electrodes may be filter output electrodes.
Abstract:
A switchable filter may include a first acoustic resonator including first electrodes, and a first resonant layer between the first electrodes and having electrostrictive material. The switchable filter may further include a second acoustic resonator including second electrodes, and a second resonant layer between the second electrodes and having electrostrictive material. The second acoustic resonator may be acoustically coupled with the first acoustic resonator. At least one of the first electrodes and at least one of the second electrodes may be arranged between the first resonant layer and the second resonant layer. The electrostrictive material may adjust a resonance and a filter switching of the first and second acoustic resonators as a function of a control voltage applied to terminals of the first and second acoustic resonators. Two electrodes from one of the first electrodes and the second electrodes may be filter input electrodes. Two electrodes from one of the first electrodes and the second electrodes may be filter output electrodes.
Abstract:
A filtering circuit includes a substrate; an acoustic mirror or a membrane destined to act as a mechanical support of acoustic resonators and to isolate these resonators from the substrate; a first section comprising an upper resonator and a lower resonator coupled to each other by at least one acoustic coupling layer; and a second section comprising an upper resonator and a lower resonator coupled to each other by at least one acoustic coupling layer. The filtering circuit also includes metallic vias implementing an inter stage connection between the lower resonator of a section and the upper resonator of the other section. Preferably, the upper resonators exhibit a piezoelectric layer having a thickness selected in order to achieve an optimal impedance matching between the said first and second sections.
Abstract:
A coupled Lamb wave resonator filter includes first and second Lamb wave resonators. The first Lamb wave resonator includes a first resonant layer, and first and second electrodes on opposite sides of the first resonant layer. The second Lamb wave resonator includes a second resonant layer, and third and fourth electrodes on opposite sides of the second resonant layer. One of the sides of the first resonant layer belongs to a plane parallel to a plane corresponding to one of the sides of the second resonant layer. Both planes pass through the third and fourth electrodes of the second Lamb wave resonator. A periodic lattice acoustically couples the first and second resonant layers.
Abstract:
A coupled Lamb wave resonator filter includes first and second Lamb wave resonators. The first Lamb wave resonator includes a first resonant layer, and first and second electrodes on opposite sides of the first resonant layer. The second Lamb wave resonator includes a second resonant layer, and third and fourth electrodes on opposite sides of the second resonant layer. One of the sides of the first resonant layer belongs to a plane parallel to a plane corresponding to one of the sides of the second resonant layer. Both planes pass through the third and fourth electrodes of the second Lamb wave resonator. A periodic lattice acoustically couples the first and second resonant layers.