@misc{9240762,
  abstract     = {{Future sixth-generation (6G) wireless systems are expected to support extreme
data rates, massive connectivity, and high energy efficiency. Largescale
Multiple-Input Multiple-Output (MIMO) combined with Orthogonal
Frequency Division Multiplexing (OFDM) is a key enabling technology
to meet these demands. However, OFDM signals exhibit a high Peakto-
Average Power Ratio (PAPR), which forces power amplifiers (PAs) to
operate with significant back-off in order to satisfy Error Vector Magnitude
(EVM) and spectral emission constraints, thereby reducing transmitter efficiency.
This thesis investigates distortion-aware power allocation in OFDMbased
MIMO transmitters with a focus on 6G-oriented system design. The
work analyzes the spatial and spectral behavior of distortion introduced by
Crest Factor Reduction (CFR) and nonlinear PA characteristics. A comprehensive
simulation framework is developed based on wideband CP-OFDM
transmission, DFT beamforming, and multi-user MIMO to evaluate distortion
under spatial, frequency, and joint spatial–frequency multiplexing.
The results reveal that branch-level distortion does not directly translate
to user-experienced distortion. With increasing number of simultaneously
served users, nonlinear distortion becomes progressively decorrelated
from the desired signal components, resulting in significantly lower user
EVM compared to branch EVM. A similar decorrelation effect is observed
when users are separated in the frequency domain through sub-band allocation.
Furthermore, increasing the number of antennas enhances distortion
averaging, leading to improved user-side signal quality while branch-level
distortion remains largely unchanged.
Building on these observations, the study introduces the concept of
power overbooking, whereby additional transmit power can be allocated
without violating user-level EVM constraints. The results demonstrate that
joint exploitation of spatial and frequency resources provides measurable
power headroom gains, enabling reduced PA back-off and improved energy efficiency.
Overall, this work highlights that distortion-aware and hardware-aware
resource allocation can significantly improve transmitter performance. The
findings provide practical design insights for future large-scale MIMO systems,
where exploiting distortion decorrelation across space and frequency
becomes a key enabler for energy-efficient 6G transmitter architectures.}},
  author       = {{Sakalani, Frank Daniel and Gunasekaran, Deepa}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Distortion-Aware Power Allocation for 6G MIMO Transmitters}},
  year         = {{2026}},
}