Method for calibrating a DC offset cancellation level for direct conversion receivers

摘要

A method for measuring a difference in DC offsets associated with different gain settings in a direct conversion receiver having a variable gain is provided. In a first phase, a set of response parameters that characterize a time-dependent system response to a known change in the DC offset is determined. Each response parameter corresponds to the response measured at a different time after the change. In a second phase, different gain settings are applied to the system and the response is measured at times corresponding to the times associated with each of the response parameters. The response parameters are then used to determine the difference in DC offsets associated with the different gain settings.