Advancing wireless communications with uplink rate-splitting multiple access
File(s)
Author(s)
Liu, Yuanwen
Type
Thesis
Abstract
New services and demands for capacity and connectivity bring critical challenges to current networks and how to allocate resources more efficiently has become an important problem. This calls for reconsidering multiple access (MA) techniques in future networks. As a general and efficient MA technique, Rate-Splitting Multiple Access (RSMA) has attracted attention from academia and industry. Most of the works of RSMA are related to downlink, while exploiting uplink RSMA still needs further exploration. This thesis focused on integrating uplink RSMA with emerging techniques and enhancing the reliability of uplink RSMA.
The applications of uplink RSMA in two new techniques are investigated, namely network slicing and semantic communications. First, RSMA with network slicing is studied. Enhanced Mobile Broadband (eMBB), ultra-reliable and low-latency communications (URLLC) and massive machine type communications (mMTC) are three generic services in future networks, and network slicing is a technique to satisfy the requirements of different services. An uplink RSMA approach for network slicing is investigated to allocate spectrum resources efficiently while guaranteeing different requirements of users.
Then, the application of RSMA in the coexistence of semantic communications and bit communications is studied. Semantic communication is efficient for users who only care about the semantic meaning, but it will not completely replace bit communication, so there will be coexistence between semantic communications and bit communications in future. An uplink RSMA scheme is investigated to allocate resources between these two types of communications efficiently.
Next, considering the high reliability requirements in future networks, integrating RSMA and hybrid automatic repeat request (HARQ) is investigated. Conventional HARQ that retransmitting all the failed messages is not suitable for RSMA, since it may increase the complexity. A HARQ scheme tailored for RSMA is studied, and the results show that RSMA with HARQ has promising reliability and energy efficiency.
The applications of uplink RSMA in two new techniques are investigated, namely network slicing and semantic communications. First, RSMA with network slicing is studied. Enhanced Mobile Broadband (eMBB), ultra-reliable and low-latency communications (URLLC) and massive machine type communications (mMTC) are three generic services in future networks, and network slicing is a technique to satisfy the requirements of different services. An uplink RSMA approach for network slicing is investigated to allocate spectrum resources efficiently while guaranteeing different requirements of users.
Then, the application of RSMA in the coexistence of semantic communications and bit communications is studied. Semantic communication is efficient for users who only care about the semantic meaning, but it will not completely replace bit communication, so there will be coexistence between semantic communications and bit communications in future. An uplink RSMA scheme is investigated to allocate resources between these two types of communications efficiently.
Next, considering the high reliability requirements in future networks, integrating RSMA and hybrid automatic repeat request (HARQ) is investigated. Conventional HARQ that retransmitting all the failed messages is not suitable for RSMA, since it may increase the complexity. A HARQ scheme tailored for RSMA is studied, and the results show that RSMA with HARQ has promising reliability and energy efficiency.
Version
Open Access
Date Issued
2025-01-10
Date Awarded
01/05/2025
License URL
Advisor
Clerckx, Bruno
Publisher Department
Department of Electrical and Electronic Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)