论文标题
来自异质用户反馈的CSI传感：一种约束的相位检索方法
CSI Sensing from Heterogeneous User Feedbacks: A Constrained Phase Retrieval Approach
论文作者
论文摘要
本文调查了由具有不同反馈功能的用户设备（UES）组成的5G异质网络中的下行链路通道状态信息（CSI）传感。我们旨在提高UE的CSI准确性，仅提供低分辨率I型代码簿。尽管现有作品已经证明可以通过基于预编码矩阵指示器（PMI）和通道质量指标（CQI）的反馈来解决相位检索（PR）公式来完成任务，但它们需要许多反馈回合。在本文中，我们提出了一种新型的CSI感应方案，可以显着减少反馈开销。我们的方案涉及一种新的参数降低设计，通过利用附近UES中无线通道的空间一致性，以及由PMI信息来表征CSI可行区域的约束PR（CPR）公式。为了解决由于非跨性别性和CPR的大量约束而引起的计算挑战，我们开发了一种两阶段算法，该算法首先识别和消除了不活动的约束，然后是快速的一阶算法。该研究进一步扩展到多载体系统。对DeepMimo和Quadriga数据集进行了广泛的测试，展示了我们的设计大大优于现有方法，并通过几轮反馈来实现高分辨率II型代码簿性能。
This paper investigates the downlink channel state information (CSI) sensing in 5G heterogeneous networks composed of user equipments (UEs) with different feedback capabilities. We aim to enhance the CSI accuracy of UEs only affording the low-resolution Type-I codebook. While existing works have demonstrated that the task can be accomplished by solving a phase retrieval (PR) formulation based on the feedback of precoding matrix indicator (PMI) and channel quality indicator (CQI), they need many feedback rounds. In this paper, we propose a novel CSI sensing scheme that can significantly reduce the feedback overhead. Our scheme involves a novel parameter dimension reduction design by exploiting the spatial consistency of wireless channels among nearby UEs, and a constrained PR (CPR) formulation that characterizes the feasible region of CSI by the PMI information. To address the computational challenge due to the non-convexity and the large number of constraints of CPR, we develop a two-stage algorithm that firstly identifies and removes inactive constraints, followed by a fast first-order algorithm. The study is further extended to multi-carrier systems. Extensive tests over DeepMIMO and QuaDriGa datasets showcase that our designs greatly outperform existing methods and achieve the high-resolution Type-II codebook performance with a few rounds of feedback.
