DIGITAL PREDISTORTION VERIFICATION AND TX NONLINEARITY ESTIMATION

摘要

A digital predistortion (DPD) verification and transmitter nonlinearity estimation system includes a transmitter path including one or more power amplifiers (PAs) coupled to an upconversion mixer. A digital tone generator circuit generates a single-tone radio-frequency (RF) signal that is applied to a first input of the upconversion mixer to generate a dual-tone RF signal, where a second input of the upconversion mixer is disabled. A downconversion mixer downconverts an amplified dual-tone RF signal to generate an intermediate-frequency (IF) dual-tone signal. A processing block analyzes the IF dual-tone signal to estimate signal strengths of one or more intermodulation (IM) product signals.