Mul, Dieuwert P.N.Dieuwert P.N.MulBootsman, Rob J.Rob J.BootsmanBruinsma, QuintenQuintenBruinsmaShen, YiyuYiyuShenKrause, SebastianSebastianKrauseQuay, RüdigerRüdigerQuayPelk, Marco J.Marco J.PelkRijs, Fred vanFred vanRijsHeeres, Rob M.Rob M.HeeresPires, SergioSergioPiresAlavi, MortezaMortezaAlaviVreede, Leo C.N. deLeo C.N. deVreede2022-03-142022-03-142021https://publica.fraunhofer.de/handle/publica/41012510.23919/EuMC48046.2021.9338122An energy-efficient, intrinsically linear, digital ""class-C like"" operation-mode is investigated for use in high-power digital transmitters (DTXs), which target next generation mMIMO base stations that offer lower costs, higher integration, and improved system efficiency. The proposed operation utilizes class-B/C output matching in combination with duty-cycle reduction and current-mode operation of a segmented output stage. Its performance in terms of efficiency, output power, and linearity is benchmarked with analog class-B/C operation. The proposed digital ""class-C like"" operation has been experimentally verified using a fully-digital, dual TX line-up with VT -shifted segmented LDMOS output stages. All output stage segments are individually controlled by high-speed digital drivers implemented in 40 nm CMOS technology. The realized prototype provides25.9 W (CW) output power with 75.7 % drain and 72.9 % system efficiencies, at 930 MHz and at 28 V drain supply.enClass-Cdigital transmitterefficiencylinearityLDMOSCMOS RFICpolar transmitterRFDACdigital power amplifier667conference paper