标题： 毫米波初始对齐的CSI顺序学习 显示英文标题

标题： Sequential Learning of CSI for MmWave Initial Alignment

摘要： 毫米波通信旨在通过使用高度定向的波束来满足更高的数据速率需求，从而利用更大的带宽。 一个固有的挑战是获取毫米波传输所需的信道状态信息（CSI）。 我们研究了在毫米波通信初始对准阶段自适应和顺序学习CSI的问题。 我们专注于单用户且存在单一主导路径的场景，其中该问题等价于获取最优波束成形向量，在理想情况下，生成的波束方向应与期望分辨率下的到达角一致。 我们在之前工作的基础上提出两种算法，用于自适应和顺序地选择波束成形向量以学习CSI，并构建贝叶斯更新以考虑随时间变化的衰落模型。 数值分析表明，我们提出的算法在中断概率和预期频谱效率方面优于采用实际分层码本的策略，并展示了性能提升。 显示英文摘要

摘要： MmWave communications aim to meet the demand for higher data rates by using highly directional beams with access to larger bandwidth. An inherent challenge is acquiring channel state information (CSI) necessary for mmWave transmission. We consider the problem of adaptive and sequential learning of the CSI during the mmWave initial alignment phase of communication. We focus on the single-user with a single dominant path scenario where the problem is equivalent to acquiring an optimal beamforming vector, where ideally, the resulting beams point in the direction of the angle of arrival with the desired resolution. We extend our prior by proposing two algorithms for adaptively and sequentially selecting beamforming vectors for learning of the CSI, and that formulate a Bayesian update to account for the time-varying fading model. Numerically, we analyze the outage probability and expected spectral efficiency of our proposed algorithms and demonstrate improvements over strategies that utilize a practical hierarchical codebook.