A Wideband Sliding Digital-IF Quadrature Digital Transmitter for Multimode NB-Io

Abstract

This article proposes a sliding digital-intermediate frequency (IF) quadrature digital transmitter (Q-DTX) for multimode multiband narrowband Internet of Things/Bluetooth low-energy (NB-IoT/BLE) applications. The digital upconverter (DUC) with a reconfigurable IF frequency between 0 and fCLK is employed to replace the traditional fractional upsampling module in digital baseband processing and effectively avoid the fractional sampling spur issue. A quadrature digital power amplifier (DPA) with in