Simulink framework for the modeling of Cartesian Feedback Power Amplifier linearization systems
The Power Amplifier (PA) is a Radio Frequency (RF) circuit and its main goal is to drive the transmitter's (Tx) antenna. It faces a trade off between spectral efficiency and power saving. Digital Cartesian Feedback (CFB) presents itself as a good linearization system when using narrowband signals in portable or mobile devices. This work starts with the validation of a digital CFB linearization system using a Proportional and Integrative (PI) controller, which is able to decrease spectral side lobes of at least 20dB. Next, non linearities are added to the elements in the transmission chain in the forward and feedback paths, and the same regulator is used to linearize the system. Finally, the imperfections on the feedback are removed. The results start by validating the digital CFB linearization system, so that different configurations of non linearities can be simulated and compared. The system operates with 4QAM and 16QAM modulation, raised cosine filter, PA modeled using Salehs equation and a PI regulator.
2016 1st International Symposium on Instrumentation Systems, Circuits and Transducers (INSCIT)