PMID- 34069303 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20210604 IS - 1099-4300 (Electronic) IS - 1099-4300 (Linking) VI - 23 IP - 5 DP - 2021 May 14 TI - DRL-Assisted Resource Allocation for NOMA-MEC Offloading with Hybrid SIC. LID - 10.3390/e23050613 [doi] LID - 613 AB - Multi-access edge computing (MEC) and non-orthogonal multiple access (NOMA) are regarded as promising technologies to improve the computation capability and offloading efficiency of mobile devices in the sixth-generation (6G) mobile system. This paper mainly focused on the hybrid NOMA-MEC system, where multiple users were first grouped into pairs, and users in each pair offloaded their tasks simultaneously by NOMA, then a dedicated time duration was scheduled to the more delay-tolerant user for uploading the remaining data by orthogonal multiple access (OMA). For the conventional NOMA uplink transmission, successive interference cancellation (SIC) was applied to decode the superposed signals successively according to the channel state information (CSI) or the quality of service (QoS) requirement. In this work, we integrated the hybrid SIC scheme, which dynamically adapts the SIC decoding order among all NOMA groups. To solve the user grouping problem, a deep reinforcement learning (DRL)-based algorithm was proposed to obtain a close-to-optimal user grouping policy. Moreover, we optimally minimized the offloading energy consumption by obtaining the closed-form solution to the resource allocation problem. Simulation results showed that the proposed algorithm converged fast, and the NOMA-MEC scheme outperformed the existing orthogonal multiple access (OMA) scheme. FAU - Li, Haodong AU - Li H AUID- ORCID: 0000-0001-8184-400X AD - Department of Electrical and Electronic Engineering, The University of Manchester, Manchester M13 9PL, UK. FAU - Fang, Fang AU - Fang F AUID- ORCID: 0000-0002-6582-6570 AD - Department of Engineering, Durham University, Durham DH1 3LE, UK. FAU - Ding, Zhiguo AU - Ding Z AUID- ORCID: 0000-0001-5280-384X AD - Department of Electrical and Electronic Engineering, The University of Manchester, Manchester M13 9PL, UK. LA - eng PT - Journal Article DEP - 20210514 PL - Switzerland TA - Entropy (Basel) JT - Entropy (Basel, Switzerland) JID - 101243874 PMC - PMC8156925 OTO - NOTNLM OT - deep reinforcement learning (DRL) OT - multi-access edge computing (MEC) OT - resource allocation OT - sixth-generation (6G) OT - user grouping COIS- The authors declare no conflict of interest. EDAT- 2021/06/03 06:00 MHDA- 2021/06/03 06:01 PMCR- 2021/05/14 CRDT- 2021/06/02 01:25 PHST- 2021/03/31 00:00 [received] PHST- 2021/05/06 00:00 [revised] PHST- 2021/05/11 00:00 [accepted] PHST- 2021/06/02 01:25 [entrez] PHST- 2021/06/03 06:00 [pubmed] PHST- 2021/06/03 06:01 [medline] PHST- 2021/05/14 00:00 [pmc-release] AID - e23050613 [pii] AID - entropy-23-00613 [pii] AID - 10.3390/e23050613 [doi] PST - epublish SO - Entropy (Basel). 2021 May 14;23(5):613. doi: 10.3390/e23050613.