Rate-splitting multiple access for 6G: finite blocklength regime and non-terrestrial communications
File(s)
Author(s)
Xu, Yunnuo
Type
Thesis
Abstract
Rate-Splitting Multiple Access (RSMA) has emerged as an innovative, comprehensive, and powerful framework for the design and optimization of non-orthogonal transmission, Multiple Access (MA), and interference management strategies in next-generation wireless networks. This thesis is concerned with the performance of RSMA in the Finite Blocklength (FBL) regime and its application to multilayer satellite communications, presenting and evaluating a variety of scenarios and algorithms.
First, the performance of RSMA is investigated under Finite Blocklength (FBL) constraints across various scenarios, including unicast and multicast transmissions, with and without cooperative transmission (user-relaying). A sum-rate maximization beamforming problem and a Max-Min Fairness (MMF) beamforming problem are formulated and solved using the Successive Convex Approximation (SCA)-based algorithms. The relations between the sum-rate/MMF rate and blocklength of RSMA are investigated. RSMA is demonstrated to be promising for FBL communications.
Next, the research scope is extended from RSMA in the FBL context to its application in spectrum-sharing multilayer satellite networks. A robust interference management strategy for multilayer satellite networks is proposed, namely, Distributed-Rate Splitting Multiple Access (D-RSMA). This method mitigates interference and enhances user fairness in multilayer satellite systems and it is robust to the uncertainty of Channel State Information (CSI). A robust Semi-Definite Programming (SDP)-based iterative optimization algorithm is proposed to optimize the beamforming for achieving MMF amongst all users. The effectiveness and robustness of the proposed D-RSMA schemes for multilayer satellite networks are demonstrated through numerical results.
First, the performance of RSMA is investigated under Finite Blocklength (FBL) constraints across various scenarios, including unicast and multicast transmissions, with and without cooperative transmission (user-relaying). A sum-rate maximization beamforming problem and a Max-Min Fairness (MMF) beamforming problem are formulated and solved using the Successive Convex Approximation (SCA)-based algorithms. The relations between the sum-rate/MMF rate and blocklength of RSMA are investigated. RSMA is demonstrated to be promising for FBL communications.
Next, the research scope is extended from RSMA in the FBL context to its application in spectrum-sharing multilayer satellite networks. A robust interference management strategy for multilayer satellite networks is proposed, namely, Distributed-Rate Splitting Multiple Access (D-RSMA). This method mitigates interference and enhances user fairness in multilayer satellite systems and it is robust to the uncertainty of Channel State Information (CSI). A robust Semi-Definite Programming (SDP)-based iterative optimization algorithm is proposed to optimize the beamforming for achieving MMF amongst all users. The effectiveness and robustness of the proposed D-RSMA schemes for multilayer satellite networks are demonstrated through numerical results.
Version
Open Access
Date Issued
2024-04-15
Date Awarded
01/07/2024
License URL
Advisor
Clerckx, Bruno
Publisher Department
Electrical and Electronic Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)