Parallel Delta-Sigma Modulator-Based Digital Predistortion of Wideband RF Power Amplifiers

In this article, we propose a new robust and highly efficient digital predistortion (DPD) concept for the linearization of wideband RF power amplifiers (PAs). The proposed approach is based on combination parallelized delta-sigma modulator (DSM) forward model PA. This applies multi-rate techniques DSM that incorporates PA in its feedback loop to perform required signal predistortion. Such technique eliminates need reverse modeling associated problems. relaxes enormously clock speed requirement DPD, which allows handling high bandwidths at feasible sampling rates. Moreover, enhanced performance can be achieved without increasing order reduces sensitivity system gain variations phase distortions caused by nonlinear characteristics. Three time-interleaved parallel DPD (P-DPD) variants are described introduced, all them have been shown offer increased accuracy, consequently better compared DSM-based state-of-the-art. architectures tested assessed using extensive real-world measurements 3.6 GHz band utilizing 100 MHz 5G New Radio (NR) transmit waveforms, evidencing excellent quality.