Analysis of thermal coupling effects in integrated MIMO transmitters

Abstract

This paper presents a detailed analysis of thermal coupling and self-heating effects in highly integrated wireless transmitters. A MIMO transmitter prototype consisting of two closely integrated power amplifiers was built and modelled through microwave and thermal characterizations. The thermal behavior was extracted using FEM software and modelled with an equivalent RC network. The PA model was obtained experimentally using a pulsed setup. An RF-thermal simulator was developed and used with the models to predict joint thermal and electrical behavior. Measurements with modulated communication signals were done and compared with the simulator to demonstrate its feasibility for analysis of thermal effects in highly integrated transmitter applications.