| 摘要 |
A method and apparatus for adaptively correcting D.C. offset errors imposed upon signals in a communication device. The invention includes a feedback loop correction circuit (122) and method for measuring and reducing D.C. offset errors imposed upon analog transmission signals by transmit digital-to-analog converters (DACs) (102) and associated analog reconstruction filters. A digital feedback loop is used to remove D.C. offset errors from the analog transmission signals prior to transmission. In one embodiment, the digital feedback loop includes a pair of analog-to-digital converters, a digital D.C. offset correction circuit (222), and a pair of adders (228, 230). The transmission signals are digitized, filtered, and digitally processsed by correction circuit (222) to generate offset correction signals that are equal to undesired D.C. offset error present in the transmission signals. The correction signals are added to digital input baseband signals thereby removing undesirable D.C. offset errors from transmission signals. |
