A 1.5-1.9-GHz all-digital tri-phasing transmitter with an integrated multilevel class-D power amplifier achieving 100-MHz RF bandwidth

Loading...
Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2019-06-01
Major/Subject
Mcode
Degree programme
Language
en
Pages
11
1517-1527
Series
IEEE Journal of Solid-State Circuits, Volume 54, issue 6
Abstract
We present a prototype RF transmitter with an integrated multilevel class-D power amplifier (PA), implemented in 28-nm CMOS. The transmitter utilizes tri-phasing modulation, which combines three constant-envelope phase-modulated signals with coarse amplitude modulation in the PA. This new architecture achieves the back-off efficiency of multilevel outphasing, without linearity-degrading discontinuities in the RF output waveform. Because all signal processing is performed in the time domain up to the PA, the entire system is implemented with digital circuits and structures, thus also enabling the use of synthesis and place-and-route CAD tools for the RF front end. The effectiveness of the digital tri-phasing concept is supported by extensive measurement results. Improved wideband performance is validated through the transmission of orthogonal frequency-division multiplexing (OFDM) bandwidths up to 100 MHz. Enhanced reconfigurability is demonstrated with non-contiguous carrier aggregation and digital carrier generation between 1.5 and 1.9 GHz without a frequency synthesizer. For a 20-MHz 256-QAM OFDM signal at 3.5% error vector magnitude (EVM), the transmitter achieves 22.6-dBm output power and 14.6% PA efficiency. Thanks to the high linearity enabled by tri-phasing, no digital predistortion is needed for the PA.
Description
| openaire: EC/H2020/704947/EU//ADVANTAG5
Keywords
All-digital transmitter, class-D power amplifier (PA), digital interpolating phase modulator (DIPM), multilevel outphasing, tri-phasing
Other note
Citation
Lemberg, J, Martelius, M, Roverato, E, Antonov, Y, Nieminen, T, Stadius, K, Anttila, L, Valkama, M, Kosunen, M & Ryynänen, J 2019, ' A 1.5-1.9-GHz all-digital tri-phasing transmitter with an integrated multilevel class-D power amplifier achieving 100-MHz RF bandwidth ', IEEE Journal of Solid-State Circuits, vol. 54, no. 6, 8672775, pp. 1517-1527 . https://doi.org/10.1109/JSSC.2019.2902753