A novel method to remove the mismatch of the up-conversion mixer for a low IF transmitter

In these days the low IF transceiver architecture has been studied in a deep and active manner due to its merits of miniaturization and low cost. Although, a transmittal part regulates the output of spurious signal using the image rejection mixers, the spurious output is produced by the mismatch between two paths (I and Q) of the up-conversion mixer. In this study, the novel method to remove the mismatch of up-conversion mixer for a low IF transmitter is proposed and verified by a computer simulation. This method provides the way to calibrate the mismatch by transmitting signal and consecutively extracting the mismatch level, and is also used in various systems because it can extract amplitude mismatch and phase mismatch separately. By using this method, the spurious rejection ratio is estimated to be more than 40 dB.