Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter
AbstractIn this paper, a dual-branch topology driven by a Delta-Sigma Modulator (DSM) with a complex quantizer, also known as the Complex Delta Sigma Modulator (CxDSM), with a 3-level quantized output signal is proposed. By de-multiplexing the 3-level Delta-Sigma-quantized signal into two bi-level streams, an efficiency enhancement over the operational frequency range is achieved. The de-multiplexed signals drive a dual-branch amplification block composed of two switch-mode back-to-back power amplifiers working at peak power. A signal processing technique known as quantization noise reduction with In-band Filtering (QNRIF) is applied to each of the de-multiplexed streams to boost the overall performances; particularly the Adjacent Channel Leakage Ratio (ACLR). After amplification, the two branches are combined using a non-isolated combiner, preserving the efficiency of the transmitter. A comprehensive study on the operation of this topology and signal characteristics used to drive the dual-branch Switch-Mode Power Amplifiers (SMPAs) was established. Moreover, this work proposes a highly efficient design of the amplification block based on a back-to-back power topology performing a dynamic load modulation exploiting the non-overlapping properties of the de-multiplexed Complex DSM signal. For experimental validation, the proposed de-multiplexed 3-level Delta-Sigma topology was implemented on the BEEcube™ platform followed by the back-to-back Class-E switch-mode power amplification block. The full transceiver is assessed using a 4th-Generation mobile communications standard LTE (Long Term Evolution) standard 1.4 MHz signal with a peak to average power ratio (PAPR) of 8 dB. The dual-branch topology exhibited a good linearity and a coding efficiency of the transmitter chain higher than 72% across the band of frequency from 1.8 GHz to 2.7 GHz. View Full-Text
Share & Cite This Article
Arfi, A.B.; Elsayed, F.; Aflaki, P.M.; Morris, B.; Ghannouchi, F.M. Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter. Sensors 2018, 18, 626.
Arfi AB, Elsayed F, Aflaki PM, Morris B, Ghannouchi FM. Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter. Sensors. 2018; 18(2):626.Chicago/Turabian Style
Arfi, Anis Ben; Elsayed, Fahmi; Aflaki, Pouya M.; Morris, Brad; Ghannouchi, Fadhel M. 2018. "Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter." Sensors 18, no. 2: 626.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.