Apparatus and method for sensing and converting radio frequency to direct current
US8766724B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2011 |
| Grant date | Jul 1, 2014 |
| Priority date | — |
| Expiry date | Feb 23, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/462
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The apparatus and method thereof accurately sense and convert a radio frequency (RF) current signal to direct current (DC) independent of process variation and temperature, and without requiring high speed, high voltage amplifiers for its operation. The apparatus comprises an AC coupled circuit that couples the RF signal from the main device to a sense device with an N:M ratio, a low pass filter system that extracts the DC content of the RF current signal, and a negative feedback loop that forces the DC content of the main device and the sensed device to be equal. Exemplary embodiments include a current sensor that provides feedback to protect an RF power amplifier from over-current condition, and a RF power detection and control in a RF power amplifier (PA) that multiplies the sensed output current by the sensed output voltage to be used as a feedback to control the PA's bias.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.