Calibrated DC compensation system for a wireless communication device configured in a zero intermediate frequency architecture
US6735422B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Oct 2, 2000 |
| Grant date | May 11, 2004 |
| Priority date | — |
| Expiry date | Aug 22, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0016
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A calibrated DC compensation system for a wireless communication device configured in a zero intermediate frequency (ZIF) architecture. The device includes a ZIF transceiver and a baseband processor, which further includes a calibrator that periodically performs a calibration procedure. The baseband processor includes gain control logic, DC control logic, a gain converter and the calibrator. The gain converter converts gain between the gain control logic and the DC control logic. The calibrator programs the gain converter with values determined during the calibration procedure. The gain converter may be a lookup table that stores gain conversion values based on measured gain of a baseband gain amplifier of the ZIF transceiver. The gain control logic may further include a gain adjust limiter that limits change of a gain adjust signal during operation based on a maximum limit or on one or more gain change limits. A second lookup table stores a plurality of DC adjust values, which are added during operation to further reduce DC offset. The calibration procedure includes sampling an output signal for each gain step of the baseband amplifier at two predetermined range values and corresp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.