Resource Allocation in Virtualized CoMP-NOMA HetNets: Multi-Connectivity for Joint Transmission

Abstract

In this work, we design a generalized joint transmission coordinated\nmulti-point (JT-CoMP)-non-orthogonal multiple access (NOMA) model for a\nvirtualized multi-infrastructure network. In this model, all users benefit from\nmultiple joint transmissions of CoMP thanks to the multi-connectivity\nopportunity provided by wireless network virtualization (WNV) in\nmulti-infrastructure networks. The NOMA protocol in CoMP results in an\nunlimited NOMA clustering (UNC) scheme, where the order of each NOMA cluster is\nthe maximum possible value. We show that UNC results in maximum successful\ninterference cancellation (SIC) complexity at users. In this regard, we propose\na limited NOMA clustering (LNC) scheme, where the SIC is performed to only a\nsubset of users. We formulate the problem of joint power allocation and user\nassociation for the UNC and LNC schemes. Then, one globally and one locally\noptimal solution are proposed for each problem based on mixed-integer monotonic\noptimization and sequential programming, respectively. Numerical assessments\nreveal that WNV and LNC improves users sum-rate and reduces users SIC\ncomplexity by up to $35\\%$ and $46\\%$ compared to the non-virtualized CoMP-NOMA\nsystem and UNC model, respectively. Therefore, the proposed algorithms are\nsuitable candidates for the implementation on open and intelligent radio access\nnetworks.\n