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 Paper ID N.3.3 Paper Title Extending the Optimality Range of Multi-Antenna Coded Caching with Shared Caches Authors Emanuele Parrinello, Petros Elia, EURECOM, France; Eleftherios Lampiris, Technical University of Berlin, Germany Session N.3: Coded Caching I Presentation Lecture Track Networking and Network Coding Manuscript Click here to download the manuscript Virtual Presentation Click here to watch in the Virtual Symposium Abstract This work considers the cache-aided multiple-input single-output broadcast channel (MISO BC) where an $L$-antenna transmitter serves $K$ receiving users, each assisted by one of $\Lambda < K$ caches with normalized capacity $\gamma$. For this setting it was known that in the range of $L \in [K/\Lambda,K\gamma]$, one can achieve a Degrees-of-Freedom (DoF) performance of $L+K\gamma$. This very restrictive constraint that $L\leq K\gamma$ excluded shared-cache settings with a large number of antennas from achieving the maximum DoF; for the more realistic regime of $L>K\gamma$, all existing coded caching schemes suffer substantially reduced caching or multiplexing gains. Our work provides a novel coded caching scheme that achieves the exact best known, near optimal, DoF $L+K\gamma$, and does so even if $L>K\gamma$, thus covering an important hole in identifying the optimal performance for the multi-antenna shared-cache problem. Therefore, our work reveals that shared-cache systems with many transmit antennas can also enjoy both full multiplexing gains ($L$) as well as full caching gains $(K\gamma)$ despite the sharing of the caches. A side benefit of this scheme is its applicability in multi-antenna settings with dedicated users caches, where it can offer the advantage of reducing the subpacketization without sacrificing the DoF performance.

Plan Ahead

IEEE ISIT 2021

2021 IEEE International Symposium on Information Theory

11-16 July 2021 | Melbourne, Victoria, Australia