We consider scheduling and resource allocation in long-term evolution (LTE) networks across voice over LTE (VoLTE) and best-effort data users. The difference between these two is that VoLTE users get scheduling priority to receive their required quality of service. As we show, strict priority causes data services to suffer. We propose new scheduling and resource allocation algorithms to maximize the sum- or proportional fair (PF) throughout amongst data users while meeting VoLTE demands. Essentially, we use VoLTE as an example application with both a guaranteed bit-rate and strict application-specific requirements. We first formulate and solve the frame-level optimization problem for throughput maximization; however, this leads to an integer problem coupled across the LTE transmission time intervals (TTIs). We then propose a TTI-level problem to decouple scheduling across TTIs. Finally, we propose a heuristic, with extremely low complexity. The formulations illustrate the detail required to realize resource allocation in an implemented standard. Numerical results show that the performance of the TTI-level scheme is very close to that of the frame-level upper bound. Similarly, the heuristic scheme works well compared to TTI-level optimization and a baseline scheduling algorithm. Finally, we show that our PF optimization retains the high fairness index characterizing PF-scheduling.
@cite_18: Abstract Long Term Evolution is standardized by the 3rd Generation Partnership Project to provide a high data rate up to 100 Mbps and 50 Mbps for downlink and uplink transmission respectively and can operate in different bandwidths ranging from 1.4 MHz up to 20 MHz. The incorporated scheduling mechanisms can significantly contribute to this goal. Scheduling mechanism is the process of allocated the resources (Time and Frequency) to users transmitting different flows in same time. In this paper, a novel scheduling algorithm is presented, modeled and compare to basic scheduler used in downlink LTE transmission, such as Round Robin, Max Rate and Proportional fair schedulers. Simulation results, presented in this paper, show that the newly proposed algorithm improves system capacity as compare with Proportional Fair scheduler with guaranty of 80 fairness between all users.
@cite_37: The envisaged high data rates of Long Term Evolution- Advanced (LTE-Advanced) systems necessitate the requirement of high spectral efficiency. To meet the spectral efficiency requirements of LTE-Advanced systems, a novel resource scheduling algorithm is proposed in this paper. Since LTE-Advanced systems are expected to be deployed in a two-tier cell architecture, where femtocells will be deployed as the second tier, the proposed scheduling algorithm employs a resource reuse strategy that reuses resources among femtocells. In addition, the proposed scheduling algorithm uses the Proportional Fair (PF) scheduling principle as its baseline scheduling strategy. An explicit interference coordination strategy as well as a new mechanism to improve the system fairness performance is explored. A system level simulation is carried out to evaluate the performance of the proposed scheduling algorithm in meeting the spectral efficiency requirements of LTE-Advanced systems.
@cite_26: Long Term Evolution (LTE) is a cellular technology developed to support diversity of data traffic at potentially high rates. 3GPP's LTE is defined by the standardization body's Release 8 and 9. A key mechanism in the LTE traffic handling is the packet scheduler, which is in charge of allocating resources to active flows in both the frequency and time dimension. The scheduling scheme used largely impacts the throughput of individual users as well as throughput of the cell. It is worthwhile to evaluate the throughput and fairness conditions for different scheduling schemes before the actual deployment of LTE scheduler. Our main contribution in this study is to evaluate and compare the performance of six scheduling schemes designed for LTE network in terms of user's throughput and fairness. The findings from our performance evaluation presented to draw conclusions on the performance of the six schedulers, and point out the strengths and weakness that are common to schedulers under study. This would help design the scheme of the scheduler at the eNodeB appropriately.
@cite_29: 
@cite_21: Long term evolution is standardized by the 3rd Generation Partnership Project to provide a high data rate up to 100 and 50 Mbps for downlink and uplink transmission respectively and can operate in different bandwidths ranging from 1.4 up to 20 MHz. Downlink LTE system is based on the OFDMA technique and uses several enhanced techniques in order to increase the spectral efficiency and aggregate the cell throughput. The incorporated scheduling mechanisms can significantly contribute to this goal. Scheduling mechanism is the process of allocated the resources (time and frequency) to users transmitting different flows in same time. In this paper, we propose a novel scheduling algorithm for downlink transmission in LTE system. The performances of the newly scheduler are simulated and compare to the performances of three basic scheduler such as Round Robin, Proportional Fair and Max Rate.
@cite_1: In this paper we evaluate the performance of Packet Scheduling (PS) for different packet scheduling algorithms of 3GPP UTRAN Long Term Evolution (LTE) Downlink. Packet scheduling is importance in 3G LTE, because different types of traffic with different Quality of Service requirements are competing of the resources. In this paper, packet scheduler for LTE downlink is described. Comparison of three basic packet scheduling algorithm with their simulation result with different amount of fairness is explained. This paper shows that by dividing the packet scheduler into a time domain, frequency domain and also utilizing those using different algorithms, the throughput fairness between users can be effectively controlled.
These three basic scheduling algorithms are modelled and compared in @cite_21 and @cite_1 in terms of both throughput and fairness index. @cite_26 , the authors compare six scheduling schemes including round robin, max rate, Kwan max throughput, MaxMin, PF, and resource fair (RF) via simulations. @cite_18 a new scheduling mechanism is proposed to increase the throughput compared to PF and round robin schedulers, while losing only 20 For multi-tier networks a scheduling algorithm based on PF scheduling and frequency reuse is developed in @cite_37 . The work in @cite_29 develops resource allocation for Coordinated Multi-Point transmission in LTE-Advanced to ensure a good tradeoff between cell-average and cell-edge spectral efficiency. Most of these works consider non-GBR users only (while we propose novel scheduling algorithms which consider two different services non-GBR and GBR services).