An IQ Image Cancellation Method for Digital-Intensive Transmitters
Sprache des Titels:
Proceedings of the IEEE International Symposium on Circuits and Systems (ISCAS 2019)
The stringent requirements from 3rd Generation Partnership Project (3GPP) standards pose a big challenge for the design of cellular radio frequency transmitters. Architectural limitations and non-ideal effects of state-of-the-art complementary metal-oxide-semiconductor (CMOS) devices need to be carefully addressed to achieve sufficient performance
at low costs. In this work, the systematic problem of an IQ image in digital-intensive IQ transmitters is analyzed. The root cause is explained and an efficient cancellation method is presented. A proof of concept for long term evolution (LTE) signals is given via Matlab simulation results and measurements from a test chip implemented in 28 nm Complementary Metal-Oxide-Semiconductor (CMOS). The proposed concept improves the error vector magnitude up to 4% for wideband signals.