Joint predistortion of IQ impairments and PA nonlinearity in concurrent tri-band transmitters with a dual-up-conversion architecture

I/Q impariments of the I/Q modulator is an inevitable influence factor of the performance of wireless transmitters. The conventional tri-up-conversion (TUC) architecture includes three I/Q modulators, so when utilize digital predistortion (DPD) to linearize the power amplifier, the linearization performance would be deteriorated. This paper proposed a novel dual-up-conversion (DUC) architecture to linearize concurrent tri-band signal, which contains only two I/Q modulators and simpler than the conventional TUC architecture. A joint predistorter applied to this new architecture to compensate the I/Q imbalance and PA's nonlinearity together is proposed as well. Measurement results show that the proposed joint predistorter's linearize performance is acceptable for the proposed architecture.