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arXiv · 1710.06825

Nonlinear Precoding for Phase-Quantized Constant-Envelope Massive MU-MIMO-OFDM

Sven Jacobsson·Oscar Castañeda·Charles Jeon·Giuseppe Durisi·Christoph Studer
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Abstract

We propose a nonlinear phase-quantized constant-envelope precoding algorithm for the massive multi-user (MU) multiple-input multiple-output (MIMO) downlink. Specifically, we adapt the squared-infinity norm Douglas-Rachford splitting (SQUID) precoder to systems that use oversampling digital-to-analog converters (DACs) at the base station (BS) and orthogonal frequency-division multiplexing (OFDM) to communicate over frequency-selective channels. We demonstrate that the proposed SQUID-OFDM precoder is able to generate transmit signals that are constrained to constant envelope, which enables the use of power-efficient analog radio-frequency circuitry at the BS. By quantizing the phase of the resulting constant-envelope signal, we obtain a finite-cardinality transmit signal that can be synthesized by low-resolution (e.g., 1-bit) DACs. We use error-rate simulations to demonstrate the superiority of SQUID-OFDM over linear-quantized precoders for massive MU-MIMO-OFDM systems.

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Sven Jacobsson, Oscar Castañeda, Charles Jeon, Giuseppe Durisi, Christoph Studer. 2017-10-18. Nonlinear Precoding for Phase-Quantized Constant-Envelope Massive MU-MIMO-OFDM. https://arxiv.org/abs/1710.06825

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