Patent ID: 6381286
Filing Date: 2002-04-30
Classification: H03F

Abstract:
A cartesian loop for transmitting base band signals, said cartesian loop operating in a communication system having a plurality of time slots, said cartesian loop comprising:a forward path having a first input for the baseband signals and a second input, the forward path including means to upconvert the input signals to an RF signal for transmission; a feedback path for providing an error signal input indicative of the non-linearity of the forward path to the second input of the forward path, the feedback path having an input from the forward path and means to downconvert the input from the forward path; control means for disabling the input to the feedback path; means for sensing and acquiring a DC offset in the feedback path when the forward path is disabled; and means for subtracting the DC offset from the feedback path; wherein the DC offset is stored before the time slot in which communication is to take place, becomes active.