LARGE Characterization of Power GaN FETs and PAs Linearity at Different Load Impedances Under CW Conditions and Multitone Signals Based on the USRP LFTX Daughterboard
This paper introduces a test bench to characterize the linearity of a packaged power GaN-HEMT or power amplifiers (PAs) to assess the linearity using continuous waves and multitone signals. The proposed test setup uses an RF daughter board and a Universal Software Radio Peripheral (USRP) instead of an Arbitrary Wave Generator (AWG) to generate the tones in the baseband. A VNA is used along with the Spectrum Analyzer Option (SA) to acquire the incident and reflected multitone signals at the input and output of the Device Under Test (DUT). The load-pull system is completely calibrated and can characterize the transistor or the PA linearity, such as the static AM-AM, AM-PM, C/I, and IMD at any load impedance.