Resource Allocation for mmWave-NOMA Communication through Multiple Access Points Considering Human Blockages

In this paper, a novel framework for optimizing the resource allocation in a millimeter-wave-non-orthogonal multiple access (mmWave-NOMA) communication for crowded venues is proposed. MmWave communications suffer from severe blockage caused by obstacles such as the human body, especially in a dense region. Thus, a detailed method for modeling the blockage events in the in-venue scenarios is introduced. Also, several mmWave access points are considered in different locations. The resource allocation problem in this network is formulated in the form of an optimization problem to maximize the network sum rate, which is NP-hard. Hence, a three-stage low-complex solution is proposed to solve the problem. At first, a user scheduling algorithm, i.e., modified worst connection swapping (MWCS), is proposed. Secondly, the antenna allocation problem is solved using the simulated annealing algorithm. Afterward, to maximize the network sum rate and guarantee the quality of service constraints, a non-convex power allocation optimization problem is solved by adopting the difference of convex programming approach. The simulation results show that, under the blockage effect, the proposed mmWave-NOMA scheme performs, on average, $12\%$ better than the conventional mmWave-orthogonal multiple access (OMA) scheme. In addition, the proposed scheme considering blockage even outperforms the corresponding OMA system without blockage.Comment: 12 pages, 10 figures, this work has been submitted to the IEEE for possible publicatio