ABSTRACT
The mobile network has been developing for the past few years rapidly. The addition of emerging real-time services in cellular systems has created new challenges. The Long Term Evolution (LTE) is standardized by the 3rd Generation Partnership Project (3GPP), and it intends to create a new radio-access technique that provides high data rates and a low latency. It is not a problem to execute a lot of services in LTE operating at the same time, but it is difficult to assign the finite radio resource efficiently. In order to provide high-quality services, the Media Access Control (MAC) layer in LTE has adopted the concept of the Quality of Service (QoS), and the MAC scheduling becomes an important issue of the resource allocation. Scheduling is the process of dynamically allocating physical resources to User Equipment (UE) based on scheduling algorithms implemented at the LTE evolved NodeB (eNB). Due to the features of the Earliest Deadline First (EDF) scheduling algorithm it is ideal for real-time services. Therefore, considering the QoS requirements of the emerging real-time services, we propose the EDF-based scheduling algorithm, which takes the Channel Quality Indicator (CQI) into account in this paper. It is called the modified EDF with the Channel Quality (mECQ) for Guaranteed Bit Rate (GBR) services in downlink. Finally the results of simulation in NS-3 show that our proposed scheduling scheme can reduce the packet loss ratio, delay and increase the throughput of the whole system.
