This paper studies cache-aided wireless networks in the presence of active intelligent reflecting surfaces (IRSs) from an information-theoretic perspective. Specifically, we investigate interference management in a cache-aided wireless network assisted by an active IRS to enhance the achievable degrees of freedom (DoF). To this end, we jointly design the content placement, delivery phase, and IRS coefficients, and propose a one-shot achievability scheme. Our scheme exploits transmitters' cooperation, cache contents, interference alignment, and IRS capabilities, based on the network parameters. We derive the achievable one-shot sum-DoF for different cache sizes, network configurations, and numbers of IRS elements, followed by an upper bound. Our results highlight the potential of deploying an IRS in cache-aided wireless communication systems. In particular, they underscore the enhancement of achievable DoF for various parameter regimes, especially when cache sizes are inadequate. Notably, we show that access to an IRS with a sufficient number of elements enables the achievement of the maximum possible DoF for various parameter regimes of interest.

翻译：本文从信息论角度研究了存在主动智能反射表面（IRS）的缓存辅助无线网络。具体而言，我们探讨了在主动IRS辅助下的缓存辅助无线网络中的干扰管理问题，以提升可达自由度（DoF）。为此，我们联合设计了内容放置、传输阶段及IRS系数，并提出了一种单次可达性方案。该方案基于网络参数，充分利用了发射机协作、缓存内容、干扰对齐及IRS能力。我们针对不同缓存大小、网络配置及IRS单元数量推导了可达单次总和自由度，并给出了上界。研究结果突显了在缓存辅助无线通信系统中部署IRS的潜力。尤其值得关注的是，这些结果强调了在不同参数区间内（特别是当缓存容量不足时）对可达自由度的提升作用。值得注意的是，我们证明了当IRS具备足够数量的单元时，可在多种关键参数区间内实现最大可能的自由度。