The simplified digital predistortion with low-rate ADC for 5G NR signals

For the wideband communication such as the 5G NR (new radio) standard, the conventional digital pre-distortion (DPD) schemes require a high-speed ADC with a sampling rate as high as 5 times of the signal bandwidth. Since the high rate ADC is very expensive and power consuming, the DPD with low-rate ADC has been studied in this paper, and we employ the spectral extrapolation technique which extrapolates the incomplete feedback signal spectrum to recovery the information of out-of-band. Furthermore, we propose a simplified spectral extrapolation solution for the wideband DPD approach for 5G NR signal, which can achieve the similar performance of DPD with the high-speed sampling rate ADC.