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We present a novel low-complexity scheme for cache-aided communication, where a multi-antenna base station serves multiple single-antenna mobile users. The scheme is based on dividing the users into meta-users, where all users in the same meta-user store the same content during the placement phase. The inter meta-user interference is mitigated by using the cache as well as zero forcing, while the interference between users of the same meta-user is mitigated by zero forcing. Compared to the current state of the art, this scheme is feasible for a wider range of parameters. Moreover, while still achieving the optimal number of degrees of freedom (DoF), the proposed scheme imposes the same or less complexity compared to all the known schemes for each set of parameters. Consequently, the proposed scheme enables practical implementation of cache-aided communication for a large number of users.
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Simple Caching Schemes for Non-homogeneous MISO Cache-Aided Communication via Convexity
We present a novel scheme for cache-aided communication over multiple-input and single output (MISO) cellular networks. The presented scheme achieves the same number of degrees of freedom as known coded caching schemes, but, at much lower complexity. The scheme is derived for communication systems with heterogeneous rates and finite signal-to-noise ratio, in which links are modeled by wideband fading channels. The base station is serving multiple users simultaneously, by sending a combination of several packets, each intended for one user. The interference is either suppressed using the cache content or nulled by zero-forcing at the unintended users. We focus on efficient coding schemes, which allow for a maximum number of users to be served throughout the course of communication. An achievable rate region is characterized by determining the extreme rate vectors satisfying an efficient transmission. The analysis results in a simple scheduling scheme and in a closed-form performance analysis.
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- Award ID(s):
- 1749981
- PAR ID:
- 10164734
- Date Published:
- Journal Name:
- ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
- Page Range / eLocation ID:
- 4980 to 4984
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICASSP40776.2020.9053936
