Enhanced User Grouping and Pairing Scheme for CoMP-NOMA-based Cellular Networks

Abstract

Non-orthogonal multiple access (NOMA) has been identified as one of the promising technologies to enhance the spectral efficiency and throughput for the fifth generation (5G) and beyond 5G cellular networks. Alternatively, Coordinated multi-point transmission and reception (CoMP) improves the cell edge users' coverage. Thus, CoMP and NOMA can be used together to improve the overall coverage and throughput of the users. However, user grouping and pairing for CoMP-NOMAbased cellular networks have not been suitably studied in the existing literature. Motivated by this, we propose a user grouping and pairing scheme for a CoMP-NOMA-based system. Detailed numerical results are presented comparing the proposed scheme with the purely OMA-based benchmark system, NOMA only, and CoMP only systems. We show through simulation results that the proposed scheme offers a trade-off between throughput and coverage as compared to the existing NOMA or CoMP based system.Index Terms-Coordinated multi-point transmission and reception (CoMP), Non-orthogonal multiple access (NOMA), User grouping, User pairing schemes, fifth generation (5G) and beyond 5G cellular networks.

Impact of NOMA and CoMP Implementation Order on the Performance of Ultra-Dense Networks

“…We propose two pairing schemes to analyze the performance of CoMP and NOMAbased UDN. We also use the scheme proposed in [9] to study the CoMP and NOMA-based UDN.…”

“…Let βc i be the scheduling time fraction for CoMP-CoMP NOMA pairs and CoMP OMA users and βb i be the scheduling time fraction of (non-CoMP)-(non-CoMP) NOMA pairs of BS b. We use [1] to compute θc , βc i , and βb i that are as follows (b) Proposed Scheme in [9] Fig. 2: Illustration of Scheme A and Proposed Scheme in [9].…”

“…We use [1] to compute θc , βc i , and βb i that are as follows (b) Proposed Scheme in [9] Fig. 2: Illustration of Scheme A and Proposed Scheme in [9].…”

“…where Ĩc is the set of (non-CoMP)-CoMP users in cluster c, Ĩoma C. Scheme Proposed in [9] The scheme in [9] differs from Scheme B in the types of user pairs formed. Further, the scheme in [9] has been proposed for a typical cellular scenario, whereas we evaluate this scheme's performance for a UDN in this paper. Only CoMP-CoMP and (non-CoMP)-(non-CoMP) NOMA pairs are formed in this scheme.…”

“…Given such conditions, CoMP and non-CoMP users' pairing is a non-trivial task. Recently, in [9], a user grouping and pairing scheme for a CoMP-NOMA-based system has been considered for a typical user and BS densities. However, the performance also depends on the order of implementation of CoMP and NOMA (NOMA-CoMP, CoMP-NOMA, etc.).…”