Voltage-current sensor with high matching directivity
US6449568B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 27, 1998 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | Feb 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/3299
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A technique for measuring the current, voltage and phase of a Radio Frequency (RF) power wave to an RF load, accounts for the finite length of the voltage and current pickups, and corrects for effects of standing wave components of voltage and current. Voltage and current are computed as complex functions of the voltage pickup signal and the current pickup signal, based on coefficients precalibrated for the predetermined radio frequency. Alternatively, a corrected current value can based on the corrected voltage value and complex load impedance. The correction coefficients can be obtained, for each of a plurality of calibrating radio frequencies within an RF range, from voltage and current pickup signals under conditions of (a) open circuit load, (b) short circuit load, (c) fixed known impedance load; and (d) one of voltage and current being applied at a precise input level to a known load from an RF calibration source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.