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Impact of Power Amplifier Nonlinearities in Multi-user Massive MIMO Downlink

Zou, Yaning ; Raeesi, Orod ; Antilla, Lauri ; Hakkarainen, Aki ; Vieira, Joao LU ; Tufvesson, Fredrik LU orcid ; Cui, Qimei and Valkama, Mikko (2015) IEEE Global Communication Conference (GLOBECOM), 2015
Abstract
In this paper, we investigate the impact of power amplifier (PA) nonlinear distortion in pre-coded multi-user large antenna or massive MIMO downlink systems. First, detailed signal and system models are derived for the received signal at single-antenna user equipment (UE) under channel-aware linear precoding in the base-station combined with behavioral models for the individual PA units, covering both single-carrier and multi-carrier modulation schemes. Based on the derived models, it is shown that the PA induced nonlinear distortion can also combine coherently in the channel, depending on the relative differences between the phase characteristics of the different PA units and the corresponding distortion terms. Furthermore, it is also... (More)
In this paper, we investigate the impact of power amplifier (PA) nonlinear distortion in pre-coded multi-user large antenna or massive MIMO downlink systems. First, detailed signal and system models are derived for the received signal at single-antenna user equipment (UE) under channel-aware linear precoding in the base-station combined with behavioral models for the individual PA units, covering both single-carrier and multi-carrier modulation schemes. Based on the derived models, it is shown that the PA induced nonlinear distortion can also combine coherently in the channel, depending on the relative differences between the phase characteristics of the different PA units and the corresponding distortion terms. Furthermore, it is also shown that the impact of nonlinear PAs and the resulting linear and nonlinear multi-user interference, quantified in terms of the received signal-to- interference-plus-noise ratio (SINR), is largely dependent on the effective or observable linear gain in the UE receiver demodulation stage. By observing only the instantaneous direct linear gain, the PA induced nonlinear distortion has a substantial impact on the effective SINR, even if very large number of TX antennas is adopted relative to the number of spatially multiplexed UEs. On the other hand, if the statistically averaged linear gain can be observed, the impact of nonlinear PAs is far less severe. These findings give thus new insight, not only to the core impact of nonlinear PAs in massive MIMO systems but also to the downlink reference signal design, radio frame design and radio resource management in time, in order to facilitate the estimation of the statistically averaged linear gains in the receivers within the scheduled transmission and processing blocks. (Less)
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author
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organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
host publication
[Host publication title missing]
conference name
IEEE Global Communication Conference (GLOBECOM), 2015
conference location
San Diego, California, United States
conference dates
2015-12-06 - 2015-12-10
external identifiers
  • scopus:84971280564
DOI
10.1109/GLOCOMW.2015.7414011
language
English
LU publication?
yes
id
c8ed3384-f781-4c48-bb12-0c78313b984b (old id 8866222)
date added to LUP
2016-04-04 13:25:08
date last changed
2022-05-01 23:57:03
@inproceedings{c8ed3384-f781-4c48-bb12-0c78313b984b,
  abstract     = {{In this paper, we investigate the impact of power amplifier (PA) nonlinear distortion in pre-coded multi-user large antenna or massive MIMO downlink systems. First, detailed signal and system models are derived for the received signal at single-antenna user equipment (UE) under channel-aware linear precoding in the base-station combined with behavioral models for the individual PA units, covering both single-carrier and multi-carrier modulation schemes. Based on the derived models, it is shown that the PA induced nonlinear distortion can also combine coherently in the channel, depending on the relative differences between the phase characteristics of the different PA units and the corresponding distortion terms. Furthermore, it is also shown that the impact of nonlinear PAs and the resulting linear and nonlinear multi-user interference, quantified in terms of the received signal-to- interference-plus-noise ratio (SINR), is largely dependent on the effective or observable linear gain in the UE receiver demodulation stage. By observing only the instantaneous direct linear gain, the PA induced nonlinear distortion has a substantial impact on the effective SINR, even if very large number of TX antennas is adopted relative to the number of spatially multiplexed UEs. On the other hand, if the statistically averaged linear gain can be observed, the impact of nonlinear PAs is far less severe. These findings give thus new insight, not only to the core impact of nonlinear PAs in massive MIMO systems but also to the downlink reference signal design, radio frame design and radio resource management in time, in order to facilitate the estimation of the statistically averaged linear gains in the receivers within the scheduled transmission and processing blocks.}},
  author       = {{Zou, Yaning and Raeesi, Orod and Antilla, Lauri and Hakkarainen, Aki and Vieira, Joao and Tufvesson, Fredrik and Cui, Qimei and Valkama, Mikko}},
  booktitle    = {{[Host publication title missing]}},
  language     = {{eng}},
  title        = {{Impact of Power Amplifier Nonlinearities in Multi-user Massive MIMO Downlink}},
  url          = {{http://dx.doi.org/10.1109/GLOCOMW.2015.7414011}},
  doi          = {{10.1109/GLOCOMW.2015.7414011}},
  year         = {{2015}},
}