A 5.5 GHz Background-Calibrated Subsampling Polar Transmitter with -41.3 DB EVM at 1024 OAM in 28NM CMOS. - Nereo Markulic; Pratap Renukaswarny; Ewout Martens; Barend van Liempd; Piet Wambacq; Jan Craninckx (VLSI Circuits, 2018)