Channel state information (CSI) is crucial for achieving ultra-reliable low-latency communication (URLLC) in wireless networks. The main associated problems are the CSI acquisition time, which impacts the delay requirements of time-critical applications, and the estimation accuracy, which degrades the signal-to-interference-plus-noise ratio (SINR), thus, reducing reliability. In this work, we formulate and solve a minimum-power precoding design problem simultaneously serving multiple URLLC users in the downlink with imperfect CSI availability. Specifically, we develop an algorithm that exploits state-of-the-art precoding schemes such as the maximal ratio transmission (MRT) and zero-forcing (ZF), and adjust the power of the precoders to compensate for the channel estimation error uncertainty based on the extreme value theory (EVT) framework. Finally, we evaluate the performance of our method and show its superiority concerning worst-case robust precoding, which is used as a benchmark.

翻译：信道状态信息对于在无线网络中实现超可靠低延迟通信至关重要。主要相关问题是信道状态信息获取时间（影响时间关键型应用的延迟需求）以及估计精度（会降低信号与干扰加噪声比，从而降低可靠性）。本文针对下行链路中同时服务多个URLLC用户且信道状态信息不可靠的情况，提出并求解了一个最小功率预编码设计问题。具体而言，我们开发了一种算法，该算法利用最大比传输和迫零等先进预编码方案，并基于极值理论框架调整预编码器功率以补偿信道估计误差的不确定性。最后，我们评估了所提方法的性能，并展示了其相对于作为基准的最坏情况鲁棒预编码的优越性。