Method and apparatus for testing frequency-dependent electrical circuits
US6518774B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 15, 2002 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | Jan 15, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Electrical filter circuits are tested by connecting test apparatus to the filter circuit inputs, without the need to connect to the filter outputs or to disconnect the outputs from a load. A signal generator of known source resistance applies a.c. signals successively over a range of frequencies to the filter circuit inputs, and a voltmeter monitors the voltage across the filter inputs. Different types of filter circuits have different characteristic shapes for the voltage/frequency curve, and processing is applied to the measured results by a computer to determine characteristics of the filter circuit, such as values of the individual sub-components of the filter circuit. An interactive process is applied to successively improve the accuracy of the component value determinations over a range of frequencies. Using the techniques described enables the insertion loss of the filter also to be readily calculated by the computer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.