Algorithm for raw rf transceiver dc offset calibration

摘要

The present invention relates to Method for compensating DC offset in a signal path comprising a plurality of stages, each stage having an individual gain and a total gain that is the product of the gains of all preceding stages and the gain of said stage, wherein for each stage a raw DC compensation is performed by introducing a raw DC compensation signal into the signal path of said stage by means of an compensation digital to analog converter that is electrically coupled to said stage; wherein said raw DC compensation signal for said stage is determined by performing raw calibration iterations, wherein a raw calibration iteration comprises the steps: measuring a DC offset residual at the output of said signal path, setting the raw DC compensation signal to a value that is the difference between the raw DC compensation signal of the preceding raw calibration iteration and the DC offset residual divided by the total gain of said stage; wherein the raw DC compensation signal of the preceding raw calibration iteration is set to zero for the first raw calibration iteration; and wherein the raw DC compensation is performed stage by stage starting with the stage that is closest to the output of said signal path. ( Fig.4 )