NETWORK SYNTHESIS DESIGN OF MICROWAVE ACOUSTIC WAVE FILTERS

• US 20140266511A1
• Filed: 03/15/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Resonant Inc. (Murata Manufacturing Co Limited)
• Inventors: Silver, Richard N., Raihn, Kurt F., Fenzi, Neal O., Hammond, Robert B., Turner, Patrick J., Willemsen Cortes, Balam Quitze Andres
• Granted Patent: US 9,038,005 B2
• Time in Patent Office: Days
• US Class Current: 333/193
• CPC Class Codes: G06F 30/327 Logic synthesis; Behaviour synthesis, e.g. mapping logic, HDL to netlist, high-level language to RTL or netlist
• CPC Class Codes: G06F 30/36 Circuit design at the analogue level
• CPC Class Codes: G06F 30/367 Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods
• CPC Class Codes: G06F 30/373 Design optimisation
• CPC Class Codes: H03H 9/46 Filters multiple-port electromechanical filters H03H9/70
• CPC Class Codes: H03H 9/465 in combination with other electronic elements
• CPC Class Codes: H03H 9/542 including passive elements H03H9/545 takes precedence
• CPC Class Codes: H03H 9/6483 Ladder SAW filters

Abstract

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.

Claims

1. 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 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.

2. The method for the design of a microwave filter of claim 1 further including the step of mapping the 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.

4. The method for the design of a microwave filter of claim 1 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.

6. The method for the design of a microwave filter of claim 1 further including the step of element removal optimization.

7. The method for the design of a microwave filter of claim 1 wherein the filter requirements are at least selected from the group comprising:

frequency dependent return loss, insertion loss, rejection, 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 wherein the circuit structure is in-line non-resonant-node.

11. The method for the design of a microwave filter of claim 1 wherein the mapping/unmapping is square-root/quadratic mapping/unmapping.

12. The method for the design of a microwave filter of claim 1 wherein the survey calculates multiple circuit responses.

13. The microwave filter formed on a substrate having the circuit design generated by the method of claim 1.

14. Computer readable software disposed in computer memory storage implementing the method of claim 1.

15. A system for the design of microwave filters comprising a computer, software stored in computer memory implementing the method of claim 1.

16. 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 circuit response 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 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, the circuit being characterized in that one or more RZ'"'"'s will lie outside any passband of the filter.

17. The method for the design of a microwave filter of claim 16 wherein the number of TZ'"'"'s may be greater than or equal to the number of RZ'"'"'s.

18. 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 circuit response variables,

calculating normalized circuit element values based on the input parameters, and generate a first circuit, characterized at least in that one or more of the resonators are widely spaced in that they are spaced greater in frequency than the frequency difference between the resonance and anti-resonance of a single resonator,

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.

19. The method for the design of a microwave filter of claim 18 wherein the frequency difference is greater than 78 MHz.

20. The method for the design of a microwave filter of claim 18 wherein the spacing between resonators varies between 1 MHz and 260 MHz.