Network synthesis design of microwave acoustic wave filters
View Patent ↗Methods for the design of microwave filters comprises comprising preferably the steps of inputting a first set of filter requirements, inputting a selection of circuit element types, inputting a selection of lossless circuit response variables, calculating normalized circuit element values based on the input parameters, and generate a first circuit, insert parasitic effects to the normalized circuit element values of the first circuit, and output at least the first circuit including the post-parasitic effect circuit values. Additional optional steps include: requirements to a normalized design space, performing an equivalent circuit transformation, unmapping the circuit to a real design space, performing a survey, and element removal optimization. Computer implement software, systems, and microwave filters designed in accordance with the method are included.
1. A method for the design of a microwave filter comprising the steps of:
inputting a set of filter requirements;
inputting a selection of circuit element types;
inputting a selection of lossless circuit response variables;
calculating normalized circuit element values based on the inputted set of filter requirements, circuit element types, and lossless circuit response variables;
generating a circuit comprising the calculated normalized circuit element values;
inserting parasitic effects in the normalized circuit element values of the circuit; and
outputting at least the circuit including the post-parasitic effect circuit values.
2. The method for the design of a microwave filter of claim 1 further including the step of mapping the set of requirements to a normalized design space.
3. The method for the design of a microwave filter of claim 1 further including the step of performing an equivalent circuit transformation on the circuit.
4. The method for the design of a microwave filter of claim 2 further including the step of unmapping the circuit to a real design space.
5. The method for the design of a microwave filter of claim 1 further including the step of performing a survey on the circuit.
6. The method for the design of a microwave filter of claim 1 further including the step of element removal optimization on the circuit.
7. The method for the design of microwave filter of claim 1 wherein the filter requirements are at least selected from the group comprising: frequency dependent return loss, insertion loss, and linearity.
8. The method for the design of a microwave filter of claim 1 wherein the circuit element type is a resonator.
9. The method for the design of a microwave filter of claim 8 wherein the resonator is a surface acoustic wave (SAW) resonator.
10. The method for the design of a microwave filter of claim 1 further comprising inputting a selection of circuit structures, wherein the normalized circuit element values are further based on the inputted circuit structure, and wherein the inputted circuit structure is in-line non-resonant-mode.
11. The method for the design of a microwave filter of claim 4 wherein the mapping/unmapping is square-root/quadratic mapping/umapping.
12. The method for the design of a microwave filter of claim 5 wherein the survey calculates multiple circuit responses.
13. A method for the design of a microwave filter comprising the steps of:
inputting a first set of filter requirements;
inputting a selection of circuit element types;
inputting a selection of lossless variables, in the form of ratios of polynomials, which include TZ's, RZ's, and a scale factor;
calculating normalized circuit element values based on the inputted set of filter requirements, circuit element types, and lossless circuit response variables;
generating a circuit comprising the calculated normalized circuit element values;
inserting parasitic effects in the normalized circuit element values of the circuit; and
outputting at least the circuit including the post-parasitic effect circuit values, the circuit being characterized in that one or more RZ's will lie outside any passband of the filter.
14. The method for the design of a microwave filter of claim 13 wherein the number of TZ's is greater than or equal to the number of RZ's.
15. A method for the design of a microwave filter comprising the steps of:
inputting a set of filter requirements;
inputting a selection of circuit element types;
inputting a selection of lossless circuit response variables;
calculating normalized circuit element values based on the inputted set of filter requirements, circuit element types, and lossless circuit response variables;
generating a circuit comprising the calculated normalized circuit element values, comprising a plurality of resonators that are spaced greater in frequency than the frequency difference between the resonance and anti-resonance of a single one of the resonators;
inserting parasitic effects to in the normalized circuit element values of the circuit; and
outputting at least the circuit including the post-parasitic effect circuit values.
16. The method for the design of a microwave filter of claim 15 wherein the frequency difference is greater than 78 MHz.
17. The method for the design of a microwave filter of claim 15 wherein the spacing between the resonators varies between 1 MHz and 260 MHz.