Coded caching (CC) can transform cache memory at network devices into an active communication resource and significantly enhance the Degrees of Freedom (DoF) of multi-input multi-output (MIMO) systems by jointly exploiting global caching and spatial multiplexing gains. Existing linearly decodable MIMO-CC designs, however, largely rely on symmetric stream allocation, where all scheduled users receive the same number of streams, which induces coarse DoF granularity and may leave spatial dimensions unused. This letter studies one-shot linearly decodable MIMO-CC delivery with arbitrary per-user stream allocations. We derive a sufficient stream-count decodability condition, expressed through per-user stream counts and multicast-codeword multiplicities, that generalizes the symmetric common-stream feasibility rule. Building on this condition, we develop a greedy multicast scheduling procedure with certified linear decodability, which redistributes coded multicast messages across transmission intervals to realize asymmetric stream allocations. Numerical results show that the proposed scheduler fills DoF-granularity gaps and improves finite-SNR symmetric rates over the state of the art.

翻译：编码缓存（CC）可将网络设备中的缓存内存转化为主动通信资源，并通过联合利用全局缓存与空间复用增益，显著提升多输入多输出（MIMO）系统的自由度（DoF）。然而，现有线性可解码的MIMO-CC设计主要依赖对称流分配（即所有调度用户接收相同数量的流），这导致自由度粒度粗糙且可能产生空间维度闲置。本文研究采用任意用户级流分配的单次线性可解码MIMO-CC传输方案。我们推导出一个流计数可解码充分条件，该条件通过用户级流计数与多播码字重数表达，推广了对称公共流可行性准则。基于该条件，我们开发了一种具有认证线性可解码性的贪心多播调度流程，通过跨传输间隔重新分配编码多播消息来实现非对称流分配。数值结果表明，所提调度器填补了自由度粒度间隙，并在有限信噪比下将对称速率提升至超过现有技术水平。