13.2 A digital multimode polar transmitter supporting 40MHz LTE Carrier Aggregation in 28nm CMOS. - Michael Fulde; Alexander Belitzer; Zdravko Boos; Michael Bruennert; Jonas Fritzin; Hans Geltinger; Marcus Groinig; Daniel Gruber; Simon Gruenberger; Thomas Hartig; Vahur Kampus; Boris Kapfelsperger; et al. (ISSCC, 2017)