论文标题
带有缓存的多安特纳（Multi-Antenna）编码内容：低复杂解决方案
Multi-Antenna Coded Content Delivery with Caching: A Low-Complexity Solution
论文作者
论文摘要
我们在单细胞网络中使用多个Antenna基站在单细胞网络中研究下行链接，为启用缓存的用户提供服务。假设一个具有共同速率的文件库，我们将用主动缓存和编码传递作为非凸件优化问题制定最小传输功率。虽然可以通过连续的凸近似（SCA）有效地解决这个多个多播问题，但问题的复杂性随着每个时间插槽的每个用户的数量而呈指数增长，这本身会随用户数量而成倍增长。我们通过分时间隔介绍了一个低复杂性替代方案，该替代方案限制了用户在每个时间插槽中接收的子文件的数量。然后，我们考虑具有稀疏性限制的波束形成和内容交付的联合设计，以限制用户在每个时间插槽中接收到的子文件的数量。数值模拟表明，低复杂性方案仅通过解决稀疏性约束的关节问题而获得的性能差距很小，并且在所有信噪比（SNR）上胜过最先进的结果，而速率值则具有足够数量的发射天线。在高复杂方案的可实现的自由度（DOF）上的下限是为了表征其在高SNR方向上的表现。
We study downlink beamforming in a single-cell network with a multi-antenna base station serving cache-enabled users. Assuming a library of files with a common rate, we formulate the minimum transmit power with proactive caching and coded delivery as a non-convex optimization problem. While this multiple multicast problem can be efficiently solved by successive convex approximation (SCA), the complexity of the problem grows exponentially with the number of subfiles delivered to each user in each time slot, which itself grows exponentially with the number of users. We introduce a low-complexity alternative through time-sharing that limits the number of subfiles received by a user in each time slot. We then consider the joint design of beamforming and content delivery with sparsity constraints to limit the number of subfiles received by a user in each time slot. Numerical simulations show that the low-complexity scheme has only a small performance gap to that obtained by solving the joint problem with sparsity constraints, and outperforms state-of-the-art results at all signal-to-noise ratio (SNR) and rate values with a sufficient number of transmit antennas. A lower bound on the achievable degrees-of-freedom (DoF) of the low-complexity scheme is derived to characterize its performance in the high SNR regime.
