Relay-aided transmission is envisioned as a key strategy to combat severe path loss and link blockages emerging as unique challenges in millimeter-wave (mmWave) communications. This work considers a relay-aided multiuser mmWave communications scenario aiming at maximizing the sum rate through optimal transmit and relay precoder design. We propose a novel joint precoder design strategy, which exploits weighted minimum mean-square error (WMMSE) using its equivalency to sum-rate maximization. We obtain closed form expressions of transmit and relay precoders, and propose to compute them through alternating-optimization iterations without having to resort to complicated numerical optimization techniques. Numerical results verify the superiority of the proposed precoding strategy as compared to conventional precoding schemes.

中文翻译：

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用于中继辅助毫米波通信中和速率最大化的多用户预编码

中继辅助传输被视为应对严重路径损耗和链路阻塞的关键策略，这些阻塞是毫米波 (mmWave) 通信中的独特挑战。这项工作考虑了中继辅助多用户毫米波通信场景，旨在通过最佳传输和中继预编码器设计最大化总速率。我们提出了一种新颖的联合预编码器设计策略，该策略利用加权最小均方误差 (WMMSE) 与总速率最大化的等效性。我们获得了传输和中继预编码器的封闭形式表达式，并建议通过交替优化迭代来计算它们，而不必求助于复杂的数值优化技术。数值结果验证了所提出的预编码策略与传统预编码方案相比的优越性。