Patent ID: 7130589

Claim:
A method for self-calibrating mismatching and non-linearity occurring in a receiver in a mobile terminal including a transmitter, the receiver, a switch for connecting an output terminal of the transmitter to an input terminal of the receiver, and a controller having an in-phase output terminal and a quadrature-phase output terminal connected to the transmitter, and having an in-phase input terminal and a quadrature-phase input terminal connected to the receiver, the method comprising the steps of: providing an output of the transmitter to the receiver via the switch; generating a first test signal associated with the in-phase output terminal and transmitting the first test signal through the transmitter; detecting an in-phase measurement signal provided via the in-phase input terminal and a quadrature-phase measurement signal provided via the quadrature-phase input terminal by processing the first test signal received via the switch in the receiver; if the quadrature-phase measurement signal does not have a value approaching ‘0’, calibrating mismatching of the quadrature-phase measurement signal by controlling the receiver, estimating distortion in the in-phase measurement signal, and then calibrating the distortion of the in-phase measurement signal by controlling the receiver; generating a second test signal associated with the quadrature-phase output terminal, and transmitting the second test signal via the transmitter; detecting an in-phase measurement signal provided via the in-phase input terminal and a quadrature-phase measurement signal provided via the quadrature-phase input terminal by processing the second test signal received via the switch in the receiver; if the in-phase measurement signal does not have a value approaching ‘0’, calibrating mismatching of the in-phase measurement signal by controlling the receiver, estimating distortion in the quadrature-phase measurement signal, and then calibrating the distortion of the quadrature-phase measurement signal by controlling the receiver; and if the calibration of the mismatching and the distortion is completed, controlling the switch to cut off a connection between the output terminal of the transmitter and the input terminal of the receiver.