A RF transmitter linearized using Cartesian Feedback in CMOS 65nm for UMTS standard

A fully CMOS transmitter including a power amplifier (PA) using a Cartesian Feedback (CFB) technique is presented. This system aims at improving the linearity of the transmitter, designed in 65nm CMOS technology from STMicroelectronics, essentially the power amplifier linearity. This transmitter delivers a maximum output power of 23dBm. Thanks to this linearization technique, the ACPR has been improved by 22dB at 5MHz from the carrier.