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Title: Energy Efficiency of Multi-User mmWave Rate-Splitting Multiple Access with Hybrid Precoding
We investigate the energy efficiency (EE) problem in a downlink multi-user millimeter wave (mmWave) rate-splitting multiple access (RSMA) system and propose an energy-efficient one-layer RSMA hybrid precoder design for K users with quality of service constraints. This scheme is applicable to the design of sustainable sixth generation (6G) cellular networks. To make the problem tractable, the analog and the digital precoder designs are decoupled. First, the analog precoder is designed to maximize the desired signal power of each user while ignoring multi-user interference. Second, the digital precoder is designed to manage multi-user interference according to the EE optimization design criterion. We adopt a successive convex approximation-based algorithm for joint optimization of the digital precoders, power, and common rate allocation. Simulation results show that the proposed RSMA scheme always performs at least as well as a baseline spatial division multiple access (SDMA) hybrid precoding scheme and outperforms it under certain channel conditions. These results suggest that RSMA is suitable as a flexible physical layer design for future 6G mmWave networks.  more » « less
Award ID(s):
2034616
PAR ID:
10620938
Author(s) / Creator(s):
;
Publisher / Repository:
IEEE
Date Published:
ISSN:
2694-2941
ISBN:
979-8-3503-0405-3
Page Range / eLocation ID:
1846 to 1851
Subject(s) / Keyword(s):
Rate-splitting multiple access (RSMA) millimeter wave (mmWave) communication energy efficiency (EE) MIMO hybrid precoding 6G mobile communication
Format(s):
Medium: X
Location:
Denver, CO, USA
Sponsoring Org:
National Science Foundation
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