Method of in-device phase measurement and correlation to programmable factors
US7457586B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2005 |
| Grant date | Nov 25, 2008 |
| Priority date | — |
| Expiry date | Aug 22, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/451
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method is provided for calibrating Amplitude Modulation to Phase Modulation (AM/PM) predistortion coefficients for a polynomial used to compensate for AM/PM distortion of a power amplifier in the transmit chain of a mobile terminal. In general, the power amplifier is controlled by a variable supply voltage, which is generated based on an adjustable power control signal. After the power amplifier is placed in the mobile terminal, a predetermined data pattern is transmitted in a transmit burst. During the transmit burst, the variable supply voltage is changed from a first value to a second value, and a resultant phase shift in the radio frequency output signal provided by the mobile terminal is measured. Based on the phase shift, one of numerous predetermined sets of AM/PM predistortion coefficients is selected as the AM/PM coefficients for the mobile terminal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.