Print Email Facebook Twitter A Four-Way Series Doherty Digital Polar Transmitter at mm-Wave Frequencies Title A Four-Way Series Doherty Digital Polar Transmitter at mm-Wave Frequencies Author Mortazavi, S.M. (TU Delft Electronics) Shen, Y. (TU Delft Electronics) Mul, D.P.N. (TU Delft Electronics) de Vreede, L.C.N. (TU Delft Electronics) Spirito, M. (TU Delft Electronics) Babaie, M. (TU Delft Electronics) Date 2022 Abstract This article presents an efficient digital polar transmitter (DPTX) at mm-wave frequencies that exploit a novel N -way series Doherty combiner (SDC) to enhance its drain and system efficiency at deep power back-off (PBO). The proposed N -way SDC is scalable and can be implemented elegantly using N transformers and N-1 shunt capacitors. As a proof of concept, a four-way Doherty DPTX is realized with the proposed SDC in which four identical but independent digital phase modulators deliver a phase-modulated constant envelope signal to their corresponding digital power amplifiers to perform the required amplitude modulation. Fabricated in a 40nm CMOS process, the proposed DPTX occupies a core area of 1.1 mathrm {mm^{2}} and exhibits 18.7dBm saturated output power and <-40dBc LO feedthrough. It demonstrates a drain efficiency of 33%/36%/22% at 0/4.5/11.5dB PBO at a 29.5GHz carrier frequency. While transmitting a 300MHz 64-QAM OFDM signal with a peak-to-average power ratio of 10.7dB, the DPTX achieves 18%/8% average drain/system efficiency, -27.6dB error vector magnitude, and -27.5dBc adjacent channel leakage ratio. To the best of our knowledge, this work is the first reported mm-wave Doherty transmitter that includes the entire chain all the way from the binary data stream up to the modulated mm-wave output signal. Subject Digital phase modulator (DPM)digital polar transmitter (DPTX)digital power amplifier (DPA)Doherty design guidemillimeter-wave transmitter (TX)power amplifier (PA)series Doherty combiner (SDC). To reference this document use: http://resolver.tudelft.nl/uuid:68490394-1a5f-48aa-951c-e2ddf1c9e7d0 DOI https://doi.org/10.1109/JSSC.2021.3133861 Embargo date 2023-07-01 ISSN 0018-9200 Source IEEE Journal of Solid State Circuits, 57 (3), 803-817 Bibliographical note Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2022 S.M. Mortazavi, Y. Shen, D.P.N. Mul, L.C.N. de Vreede, M. Spirito, M. Babaie Files PDF A_Four_Way_Series_Doherty ... encies.pdf 4.52 MB Close viewer /islandora/object/uuid:68490394-1a5f-48aa-951c-e2ddf1c9e7d0/datastream/OBJ/view