Oscillator
The invention pertains to an oscillator with a resonator element and a control element for adjusting the resonant frequency of the resonator element to a plurality of different values, wherein the resonator element consists of at least one resonator. The control element can be realized as a control layer for controlling the propagation speed of the acoustic wave in the resonator. The control element can alternatively be constructed as a switch element and be used for switching different sub-branches of a resonator element constructed as a resonator magazine or a resonator bank. A trimming element, with which fine-tuning of the oscillator frequency is possible, is preferably also provided.
1 . An oscillator comprising:
a resonator element comprising at least one resonator; and
a control element for adjusting a resonant frequency of the resonator element among a plurality of different values.
2 . The oscillator of claim 1 , further comprising:
an amplifier element; and
a resonant circuit associated with the amplifier element, the resonator element being in the resonant circuit.
3 . The oscillator of claim 2 , wherein the resonator element comprises a resonator bank comprised of resonators;
wherein the resonant circuit comprises sub-branches in parallel;
wherein a resonator is in each sub-branch; and
wherein the control element comprises a selector switch for selecting among the sub-branches.
4 . The oscillator of claim 3 , wherein the control element comprises switches; and
wherein the switch is in each sub-branch.
5 . The oscillator of claim 3 , wherein at least one of the resonators has a resonant frequency that is tunable.
6 . The oscillator of claim 3 , wherein each of the resonators has a resonant frequency that is tunable.
7 . The oscillator of claim 3 , wherein at least two of the resonators have different resonant frequencies.
8 . The oscillator of claim 4 , wherein at least one sub-branch is switched into the oscillator circuit at a given point in time.
9 . The oscillator of claim 1 , wherein the at least one resonator comprises at least one dielectric resonator.
10 . The oscillator of claim 1 , wherein the at least one resonator comprises at least one LC resonator or at least one strip-line resonator.
11 . The oscillator of claim 1 , wherein the at least one resonator comprises at least one micromechanical resonator.
12 . The oscillator of claim 1 , wherein the at least one resonator element comprises at least one electroacoustic resonator.
13 . The oscillator of claim 12 , wherein the at least one resonator comprises at least one piezoelectric layer; and
wherein the control element comprises a control layer that is in contact with the at least one piezoelectric layer; and
wherein, under mechanical stress, the control layer influences a propagation velocity of an acoustic wave in the at least one piezoelectric layer.
14 . The oscillator of claim 12 , wherein the at least one resonator comprises at least one piezoelectric layer;
wherein the control element comprises a first control layer and a second control layer, the first and second control layers forming a composite; and
wherein the second control layer comprises an additional piezoelectric layer for producing mechanical stress in first control layer in order to influence a propagation velocity of an acoustic wave in the piezoelectric layer.
15 . The oscillator of claim 13 , wherein the control layer has a giant delta effect under stress.
16 . The oscillator of claim 13 , wherein the mechanical stress is generated by a control voltage.
17 . The oscillator of claim 13 , further comprising:
an additional control element for switching between sub-branches of a resonant circuit comprised of the at least one resonator.
18 . The oscillator of claim 12 , wherein the at least one resonator comprises a thin-film resonator operating with bulk acoustic waves.
19 . The oscillator of claim 18 , wherein the at least one resonator comprises a resonator stack comprising component resonators arranged in a stack.
20 . The oscillator of claim 12 , wherein the at least one resonator operates with surface acoustic waves.
21 . The oscillator of claim 20 , wherein the at least one resonator comprises transducers that are longitudinally coupled to each other acoustically and that are arranged in an acoustic track.
22 . The oscillator of claim 2 , further comprising:
a trimming element in the resonant circuit.
23 . The oscillator of claim 22 , wherein the trimming element comprises a trimming capacitor or a trimming inductor.
24 . The oscillator of claim 22 , wherein the trimming element is in parallel with the resonator element.
25 . The oscillator of claim 22 , wherein the trimming element is in series with the at least one resonator.