Tools and methods for designing filters for use in active noise cancelling systems
AssigneeRenesas Design Netherlands B.V.
InventorsPaul Shields, Wessel Harm Lubberhuizen, Fotios Kontomichos
Life of this patent
Estimating the term…
Abstract
A computer-implemented method of automated filter design comprising designing a feedback filter for an active noise cancelling system.
Claims17
A computer-implemented method of automated filter design comprising designing a feedback filter for an active noise cancelling system;
- wherein designing the feedback filter comprises determining a filter transfer function of the feedback filter;
- wherein the filter transfer function is determined using an optimization method;
- wherein determining the filter transfer function comprises:
- defining an error function that is dependent on an open loop design target and target transfer function, the open loop design target being dependent on the filter transfer function;
- and
- applying the optimization method using the error function to determine filter expression for the filter transfer function that either:
- i) reduces the error function to a sufficiently small value that is indicative of the open loop design target being sufficiently close to the target transfer function;
- and/or
- ii) minimizes the error function.
A computer system comprising a module configured as an automated filter design tool configured to design a feedback filter for an active noise cancelling system;
- wherein designing the feedback filter comprises determining a filter transfer function of the feedback filter;
- wherein the filter transfer function is determined using an optimization method;
- wherein determining the filter transfer function comprises:
- defining an error function that is dependent on an open loop design target and target transfer function, the open loop design target being dependent on the filter transfer function;
- and
- applying the optimization method using the error function to determine filter expression for the filter transfer function that either:
- i) reduces the error function to a sufficiently small value that is indicative of the open loop design target being sufficiently close to the target transfer function;
- and/or
- ii) minimizes the error function.
An active noise cancelling system comprising a feedback filter being designed using a method of automated filter design comprising designing the feedback filter;
- wherein designing the feedback filter comprises determining a filter transfer function of the feedback filter;
- wherein the filter transfer function is determined using an optimization method;
- wherein determining the filter transfer function comprises:
- defining an error function that is dependent on an open loop design target and target transfer function, the open loop design target being dependent on the filter transfer function;
- and
- applying the optimization method using the error function to determine filter expression for the filter transfer function that either:
- i) reduces the error function to a sufficiently small value that is indicative of the open loop design target being sufficiently close to the target transfer function;
- and/or
- ii) minimizes the error function.
Dependencies are inferred from the claim text.