Multi-User MIMO Scheduling in the Fourth Generation Cellular Uplink

• Published in: IEEE transactions on wireless communications Vol. 12; no. 9; pp. 4272 - 4285
• Main Authors: Prasad, Narayan, Honghai Zhang, Hao Zhu, Rangarajan, Sampath
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.09.2013; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Approximation; Approximation algorithms; Approximation methods; Cellular; Computer simulation; Equipments and installations; Exact sciences and technology; Functions (mathematics); Interference; Knapsack; Mathematical analysis; matroid; Maximization; MIMO; Mobile radiocommunication systems; multi-user scheduling; NP-hard; Radiocommunications; resource allocation; Resource management; Scheduling; submodular maximization; Switching and signalling; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Uplink; Vectors; Wireless communication; Performance evaluation; NP-hard; Polynomial approximation; Matroid; 3G mobile communication; Wireless telecommunication; Resource allocation; Data transmission; multi-user scheduling; Polynomial method; Combinatorial optimization; Uplink; Mobile radiocommunication; MIMO system; Multiple access; Knapsack; Telecommunication standards; Scheduling; Signalling; Knapsack problem; Polynomial time; submodular maximization; Simulation; NP hard problem; Multi-stream approach; Resource management
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2013.072513.120734

We consider Multi-User MIMO (MU-MIMO) scheduling in the 3GPP LTE-Advanced (3GPP LTE-A) cellular uplink. The 3GPP LTE-A uplink allows for precoded multi-stream (precoded MIMO) transmission from each scheduled user and also allows flexible multi-user (MU) scheduling wherein multiple users can be assigned the same time-frequency resource. However, exploiting these features is made challenging by certain practical constraints that have been imposed in order to maintain a low signaling overhead. We show that while the scheduling problem in the 3GPP LTE-A cellular uplink is NP-hard, it can be formulated as the maximization of a submodular set function subject to one matroid and multiple knapsack constraints. We then propose constant-factor polynomial-time approximation algorithms and demonstrate their superior performance via simulations.