QoS-Constrained Resource Allocation Scheduling for LTE Network

QoS-Constrained Resource Allocation Scheduling for LTE Network

Hung-Chin Jang (Department of Computer Science, National Chengchi University, Taipei, Taiwan) and Yun-Jun Lee (Department of Computer Science, National Chengchi University, Taipei, Taiwan)
DOI: 10.4018/ijwnbt.2015010101

Abstract

The goal of LTE (Long Term Evolution) is to provide high data transmission rate, scalable bandwidth, low latency, high-mobility, etc. LTE employs OFDM (Orthogonal Frequency Division Multiplexing) and SC-FDMA (Single Carrier - Frequency Division Multiple Access) for downlink and uplink data transmission, respectively. As to SC-FDMA, there are two constraints in doing resource allocation. First, the allocated resource blocks (RBs) should be contiguous. Second, those of the allocated RBs are forced to use the same modulation technique. The aim of this research is to propose a QoS-constraint resource allocation scheduling to enhance data transmission for uplink SC-FDMA. The proposed scheduling is a three-stage approach. In the first stage, it uses a time domain scheduler to differentiate user equipment (UE) services according to their distinct 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 number of times of modulation downgrade of RBs allocation in order to enhance system throughput. In the simulations, the proposed method is compared to fixed sub-carrier dynamic resource allocation method and adaptive dynamic sub-carrier resource allocation method. Simulation results show that the proposed method outperforms the other two methods in terms of throughput, transmission delay, packet loss ratio, and RB utilization.
Article Preview

Method

The proposed QoS-constrained resource allocation scheduling is a three-stage approach as shown in Figure 1. In the first stage, it uses a time domain (TD) scheduler to classify services into different QoS service classes. Those services with delay constraints are specially noted. In the second stage, it uses a frequency domain (FD) scheduler to prioritize UE services based on channel quality (SINR) and calculates the amount of system available RBs. The operation flow of TD / FD scheduling is shown in Figure 2. In the third stage, it optimizes RBs allocation by appropriate modulation downgrade under the two constraints of SC-FDMA.

Complete Article List

Search this Journal:
Reset
Open Access Articles: Forthcoming
Volume 8: 2 Issues (2019): Forthcoming, Available for Pre-Order
Volume 7: 2 Issues (2018): 1 Released, 1 Forthcoming
Volume 6: 2 Issues (2017)
Volume 5: 1 Issue (2016)
Volume 4: 3 Issues (2015)
Volume 3: 4 Issues (2014)
Volume 2: 4 Issues (2012)
Volume 1: 4 Issues (2011)
View Complete Journal Contents Listing