Method for automatic impedance matching for a radiofrequency circuit and transmission or reception system with automatic matching
US8140033B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 2008 |
| Grant date | Mar 20, 2012 |
| Priority date | — |
| Expiry date | May 6, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/451
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method for automatically matching the antenna impedance for a radiofrequency transmission circuit having an amplifier. An impedance matching network is inserted between the amplifier and the antenna. The output current i and voltage V from the amplifier and their phase shift are measured, and from this the complex impedance, defined by V/i, is deduced. The antenna impedance is calculated as a function of this complex impedance and as a function of the known present values of the adjustable impedances of the matching network. New values are calculated, from the calculated value of the antenna impedance, for the adjustable impedances of the matching network that allow an overall load impedance of the amplifier to be obtained which is as close as possible to the nominal load impedance Zopt of the amplifier, and the matching network is controlled to adjust the adjustable impedances to these new values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.