Design of highly-efficient wideband RF polar transmitters using Envelope-Tracking (ET) for mobile WiMAX/Wibro applications

This paper discusses both circuits and system design aspects of highly-efficient wideband RF polar transmitters for mobile WiMAX/Wibro applications using an open-loop envelope tracking (ET) technique. The design of linear-assisted switching envelope amplifier and monolithic SiGe class-E power amplifier (PA) is discussed, while the SPICE simulation results are compared with the measurement data. WiMAX/Wibro circuit and system co-design that include RF circuits and digital DSP blocks co-simulations suggest that the entire highly integrated ET-based transmit (TX) system can meet the stringent 802.16e mobile-WiMAX TX mask with 64-QAM modulation and reach ~33% peak system efficiency.