This paper investigates the resource allocation problem combined with fronthaul precoding and access link sparse precoding design in cloud radio access network (C-RAN) wireless fronthaul systems.Multiple remote antenna units (RAUs) in C-RAN systems can collaborate in a cluster through centralized signal processing to realize distributed massive multiple-input and multiple-output (MIMO) systems and obtain performance gains such as spectrum efficiency and coverage.Wireless fronthaul is a flexible, low-cost way to implement C-RAN systems, however, compared with the fiber fronthaul network, the capacity of wireless fronthaul is extremely limited.Based on this problem, this paper first design the fronthaul and access link precoding to make the fronthaul capacity of RAUs match the access link demand.Then, combined with the precoding design problem, the allocation optimization of orthogonal resources is studied to further optimize the resource allocation between fronthaul link and access link to improve the performance of the system.Numerical results verify the effectiveness of the proposed precoding design and resource allocation optimization algorithm.

翻译：本文研究了云无线接入网（C-RAN）无线前传系统中，结合前传预编码与接入链路稀疏预编码设计的资源分配问题。C-RAN系统中的多个远程天线单元（RAU）可通过集中式信号处理在簇内协作，实现分布式大规模多输入多输出（MIMO）系统，并获得频谱效率和覆盖范围等性能增益。无线前传是实现C-RAN系统的一种灵活、低成本方式，然而，与光纤前传网络相比，无线前传的容量极为有限。基于此问题，本文首先设计前传与接入链路预编码，使RAU的前传容量与接入链路需求相匹配。随后，结合预编码设计问题，研究了正交资源的分配优化，以进一步优化前传链路与接入链路间的资源分配，从而提升系统性能。数值结果验证了所提预编码设计与资源分配优化算法的有效性。