An Optimal Standard-Compliant MIMO Scheduler for LTE Downlink

• Published in: IEEE transactions on wireless communications Vol. 13; no. 5; pp. 2412 - 2421
• Main Authors: Niafar, Samira, Zhe Huang, Tsang, Danny H. K.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-05-2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Applied sciences; Channels; Downlink; Equipments and installations; Exact sciences and technology; frequency domain packet scheduling; Information, signal and communications theory; Linear programming; Long Term Evolution; LTE; MIMO; Mobile communication systems; Mobile radiocommunication systems; Multiplexing; Optimization; Partnerships; proportional fairness; Radiocommunications; Scheduling; Scheduling algorithms; Signal and communications theory; Switching and signalling; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; total unimodularity; Transmission and modulation (techniques and equipments); Wireless communication; Performance evaluation; total unimodularity; 3G mobile communication; Wireless telecommunication; Resource allocation; Frequency division multiple access; Equity; Downlink; Optimization; Multiple task; Optimal allocation; proportional fairness; Traffic control; Selection criterion; MIMO; Modulation coding; Mobile radiocommunication; MIMO system; Packet switching; Mode selection; Teletraffic; Frequency domain method; Telecommunication standards; Linear programming; Scheduling; Simulation; Multiple system; Orthogonal frequency division multiplexing; frequency domain packet scheduling; Metric; LTE
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2013.031314.130723

Frequency domain packet scheduling (FDPS) problem is one of the crucial elements in the 3rd generation partnership project (3GPP) long term evolution (LTE) system, which has a tremendous impact on the LTE system performance. However, optimal resource allocation through FDPS is a complicated and challenging task when multiple input and multiple output (MIMO)-orthogonal frequency division multiple access (OFDMA) technology is adopted. In this paper, we propose a new FDPS scheme for the 3GPP LTE downlink channels that optimally assigns time-frequency resources to users based on the proportional fairness metric. The proposed scheme jointly considers multiple system constraints imposed by the 3GPP LTE standard that arise in the MIMO mode selection and modulation and coding scheme (MCS) selection. Such scheduling problem is considered to be among the most difficult optimization problems. Our major contribution in this paper is that we model the FDPS problem as a unique binary linear programming problem and prove that the problem is totally unimodular. With the total unimodularity property, we are able to solve the complicated FDPS problem using efficient linear programming problem solvers. Simulation results show that our proposed scheme outperforms the existing state-of-the-art MIMO proportional fair scheduling algorithms used in the FDPS problem.