{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:57:13Z","timestamp":1760241433373,"version":"build-2065373602"},"reference-count":11,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,20]],"date-time":"2018-02-20T00:00:00Z","timestamp":1519084800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In 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\u2122 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.<\/jats:p>","DOI":"10.3390\/s18020626","type":"journal-article","created":{"date-parts":[[2018,2,20]],"date-time":"2018-02-20T11:56:13Z","timestamp":1519127773000},"page":"626","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3546-4078","authenticated-orcid":false,"given":"Anis Ben","family":"Arfi","sequence":"first","affiliation":[{"name":"iRadio Lab, University of Calgary, Calgary, AB T2N 1N4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fahmi","family":"Elsayed","sequence":"additional","affiliation":[{"name":"iRadio Lab, University of Calgary, Calgary, AB T2N 1N4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pouya M.","family":"Aflaki","sequence":"additional","affiliation":[{"name":"iRadio Lab, University of Calgary, Calgary, AB T2N 1N4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brad","family":"Morris","sequence":"additional","affiliation":[{"name":"Ericsson Canada Inc., Mississauga, ON K2K 2V6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fadhel M.","family":"Ghannouchi","sequence":"additional","affiliation":[{"name":"iRadio Lab, University of Calgary, Calgary, AB T2N 1N4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,20]]},"reference":[{"key":"ref_1","first-page":"470","article-title":"Performance Analysis of Multi-Radio Transmitter with Polar or Cartesian Architectures associated with High-Efficiency Switched-Mode Power Amplifiers","volume":"19","author":"Baudoin","year":"2010","journal-title":"Radioengineering"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1007\/s11265-011-0634-6","article-title":"Efficiency Enhancement of Sigma-Delta Modulator Based Transmitters Using MultiLevel Quantizers","volume":"69","author":"Boulejfen","year":"2012","journal-title":"J. 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(2016, January 12\u201314). Broadband class-E power amplifier with high cold output impedance suitable for load modulated dual branch amplifiers. Proceedings of the 2016 IEEE MTT-S Latin America Microwave Conference (LAMC), Puerto Vallarta, Mexico.","DOI":"10.1109\/LAMC.2016.7851242"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/2\/626\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T14:55:39Z","timestamp":1760194539000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/2\/626"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,2,20]]},"references-count":11,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2018,2]]}},"alternative-id":["s18020626"],"URL":"https:\/\/doi.org\/10.3390\/s18020626","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2018,2,20]]}}}