6G FR3 Band-limited Based DPD using Low-Resolution Σ∆ Feedback Receiver

This paper presents the integration of a band-limited memory polynomial (BL-MP) digital pre-distortion (DPD) model with low-resolution Σ∆-based feedback receivers, specifically targeting 6G FR3 carrier aggregation using a 400 MHz OFDM 64QAM signal. The performance is evaluated using two power amplifiers (PAs)—Doherty and Class AB—with distinct nonlinearity profiles. The study compares the Generalized Memory Polynomial (GMP) model with the BL-MP model. Significant improvements in error vector magnitude (EVM), approximately 0.7 dBm at the 3% threshold, are observed for both PAs relative to the GMP-LS model. Additionally, adjacent channel leakage ratio (ACLR) enhancements of around 7 dB are achieved, further surpassing GMP-LS performance. These findings demonstrate the adaptability and effectiveness of the BL-MP model, delivering substantial performance gains over conventional pre-distortion techniques across varied PA architectures.The results highlight the potential of employing a BL-MP DPD with a low-resolution feedback receiver, offering an optimal solution for DPD applications in 6G FR3.