Alternating Projections Method for Joint Precoding and Peak-to-Average-Power Ratio Reduction

Sueda Taner; Christoph Studer

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arXiv · 2212.12376

Alternating Projections Method for Joint Precoding and Peak-to-Average-Power Ratio Reduction

Sueda Taner·Christoph Studer

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Abstract

Orthogonal frequency-division multiplexing (OFDM) time-domain signals exhibit high peak-to-average (power) ratio (PAR), which requires linear radio-frequency chains to avoid an increase in error-vector magnitude (EVM) and out-of-band (OOB) emissions. In this paper, we propose a novel joint PAR reduction and precoding algorithm that relaxes these linearity requirements in massive multiuser (MU) multiple-input multiple-output (MIMO) wireless systems. Concretely, we develop a novel alternating projections method, which limits the PAR and transmit power increase while simultaneously suppressing MU interference. We provide a theoretical foundation of our algorithm and provide simulation results for a massive MU-MIMO-OFDM scenario. Our results demonstrate significant PAR reduction while limiting the transmit power, without causing EVM or OOB emissions.

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Sueda Taner, Christoph Studer. 2022-12-23. Alternating Projections Method for Joint Precoding and Peak-to-Average-Power Ratio Reduction. https://arxiv.org/abs/2212.12376

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