QoS-constrained resource allocation scheduling for LTE network

Abstract

Long Term Evolution (LTE) is the most promising technology for 4G mobile communication networks. The goal of LTE is to provide high data transmission rate, scalable bandwidth, low latency, and high-mobility. LTE employs Orthogonal Frequency Division Multiplexing (OFDM) and Single Carrier - Frequency Division Multiple Access (SC-FDMA) for downlink and uplink data transmission, respectively. As to SC-FDMA, there are two constraints in resource allocation. First, the allocated resource blocks (RB) should be contiguous. Second, these allocated resource blocks are forced to use the same modulation technique. This paper focuses on the resource allocation problem of LTE SC-FDMA system. The aim of this paper is to propose a QoS-constraint resource allocation scheduling to enhance data transmission on uplink SC-FDMA. The proposed scheduling is a three-stage approach. In the first stage, it uses a time domain scheduler to differentiate UE services according to different QoS service requirements. In the second stage, it uses a frequency domain scheduler to prioritize UE services based on channel quality. In the third stage, it limits the times of modulation downgrade in RBs allocation to enhance system throughput. In the simulations, the proposed method is compared to fixed sub-carrier dynamic resource allocation algorithm and adaptive dynamic sub-carrier resource allocation algorithm. Simulation results show that our method outperforms the other two methods in terms of throughput, transmission delay, packet loss ratio, and RB utilization.