Exponential Proportional Fairness Research Articles

LTE Cellular Networks Packet Scheduling Algorithms in Downlink and Uplink Transmission: A Survey

This survey paper provides a detailed explanation of Long Term Evolution (LTE) cellular network’s packet scheduling algorithms in both downlink and uplink directions. It starts by explaining the difference between Orthogonal Frequency Division Multiple Access (OFDMA) that is used in downlink transmission, and Single Carrier – Frequency Division Multiple Access (SC-FDMA) is used in uplink. Then, it explains the difference between the LTE scheduling process in the donwlink and uplink through explaining the interaction between users and the scheduler. Then, it explains the most commonly used downlink and uplink scheduling algorithms through analyzing their formulas, characteristics, most suitable conditions for them to work in, and the main differences among them. This explanation covers the Max Carrier-toInterference (C/I), Round Robin (RR), Proportional Fair (PF), Earliest Deadline First (EDF), Modified EDF-PF, Modified-Largest Weighted Delay First (M-LWDF), Exponential Proportional Fairness (EXPPF), Token Queues Mechanism, Packet Loss Ratio (PLR), Quality Guaranteed (QG), Opportunistic Packet Loss Fair (OPLF), Low Complexity (LC), LC-Delay, PF-Delay, Maximum Throughput (MT), First Maximum Expansion (FME), and Adaptive Resource Allocation Based Packet Scheduling (ARABPS). Lastly, it provides some concluding remarks.

A novel QoE based cross-layer scheduling scheme for video applications in 802.11 wireless LANs

In the past two decades, 802.11 based Wireless Local Area Networks (WLANs) have gained popularity in offering Internet services and increasingly supporting data driven video streaming applications. Such services demand enhanced view quality to all the end-users in the network. However, due to the sharing of limited resources and lack of proper scheduling mechanisms, WLANs are unable to meet the requirements of numerous video users and provide them better quality. Therefore, an effective resource scheduling approach is needed that can achieve high user satisfaction for the ever changing user needs for quality video viewing. In this paper, a Quality of Experience based Cross-Layer Scheduling (QoECLS) scheme to enhance the user experience for video applications in WLANs is proposed. Here, the Mean Opinion Score has been used as a measure to evaluate the user experience. In order to provide the average user throughput with guarantee of fairness among users, the QoECLS scheme uses cross-layer information from the application and physical layer, respectively. The QoECLS algorithm allocates transmission resources by considering application feedback along with channel state information and buffer status. The performance of the QoECLS approach was extensively studied through simulations and the results showed an improvement in user experience and throughput, while maintaining fairness among the users. In terms of throughput, the proposed scheme achieves 25%, 45 %, and 50% improvement compared to QoE Aware Scheduling scheme, Modified-Largest Weighted Delay First scheduler and Exponential-Proportional Fair scheduler, respectively.

ITFDS: Channel-Aware Integrated Time and Frequency-Based Downlink LTE Scheduling in MANET.

One of the crucial problems in Industry 4.0 is how to strengthen the performance of mobile communication within mobile ad-hoc networks (MANETs) and mobile computational grids (MCGs). In communication, Industry 4.0 needs dynamic network connectivity with higher amounts of speed and bandwidth. In order to support multiple users for video calling or conferencing with high-speed transmission rates and low packet loss, 4G technology was introduced by the 3G Partnership Program (3GPP). 4G LTE is a type of 4G technology in which LTE stands for Long Term Evolution, followed to achieve 4G speeds. 4G LTE supports multiple users for downlink with higher-order modulation up to 64 quadrature amplitude modulation (QAM). With wide coverage, high reliability and large capacity, LTE networks are widely used in Industry 4.0. However, there are many kinds of equipment with different quality of service (QoS) requirements. In the existing LTE scheduling methods, the scheduler in frequency domain packet scheduling exploits the spatial, frequency, and multi-user diversity to achieve larger MIMO for the required QoS level. On the contrary, time-frequency LTE scheduling pays attention to temporal and utility fairness. It is desirable to have a new solution that combines both the time and frequency domains for real-time applications with fairness among users. In this paper, we propose a channel-aware Integrated Time and Frequency-based Downlink LTE Scheduling (ITFDS) algorithm, which is suitable for both real-time and non-real-time applications. Firstly, it calculates the channel capacity and quality using the channel quality indicator (CQI). Additionally, data broadcasting is maintained by using the dynamic class-based establishment (DCE). In the time domain, we calculate the queue length before transmitting the next packets. In the frequency domain, we use the largest weight delay first (LWDF) scheduling algorithm to allocate resources to all users. All the allocations would be taken placed in the same transmission time interval (TTI). The new method is compared against the largest weighted delay first (LWDF), proportional fair (PF), maximum throughput (MT), and exponential/proportional fair (EXP/PF) methods. Experimental results show that the performance improves by around 12% compared with those other algorithms.

Delay threshold scheduling algorithm for LTE downlink systems

This paper proposes a delay threshold scheduling (DTS) algorithm for the scheduling of requests in real-time multimedia applications using LTE downlink systems, which takes into account channel conditions as well as the packet waiting time. Delay thresholds were adopted to enable the differentiation of packets in conjunction with proportional weighting between channel conditions and packet waiting time for the prioritisation of real-time services. Simulation results demonstrate that compared to the results obtained using Modified Largest Weighted Delay First (M-LWDF), Exponential Proportional Fair (EXP/PF), and Channel Dependent Earliest Due Date (CD-EDD), the proposed DTS algorithm is able to increase video traffic throughput and decrease packet delays and the packet loss ratio for real-time services.

Delay threshold scheduling algorithm for LTE downlink systems

This paper proposes a delay threshold scheduling (DTS) algorithm for the scheduling of requests in real-time multimedia applications using LTE downlink systems, which takes into account channel conditions as well as the packet waiting time. Delay thresholds were adopted to enable the differentiation of packets in conjunction with proportional weighting between channel conditions and packet waiting time for the prioritisation of real-time services. Simulation results demonstrate that compared to the results obtained using Modified Largest Weighted Delay First (M-LWDF), Exponential Proportional Fair (EXP/PF), and Channel Dependent Earliest Due Date (CD-EDD), the proposed DTS algorithm is able to increase video traffic throughput and decrease packet delays and the packet loss ratio for real-time services.

Throughput enhanced scheduling (TES) scheme for ultra‐dense networks

SummaryThis paper proposes two novel packet scheduling schemes, called as throughput enhanced scheduling (TES) and TES plus (TES+), for future ultra‐dense networks. These schemes introduce two novel parameters to the scheduling decision making and reformulate the parameters used by the state‐of‐the‐art schemes. The aim is to have a more balanced weight distribution between delay and throughput‐related parameters at scheduling decisions. Also include a new telecommunications related parameter into scheduling decision making that has not been studied by popular schedulers. The performance of novel schemes is compared with well‐known schemes—proportional fairness (PF), exponential/proportional fairness (EXP/PF), and M‐LWDF. For performance evaluation, five performance metrics—average spectral efficiency and delay, quality of service (QoS) violation ratio, jitter, and Jain's fairness index—are investigated. The simulation results show that proposed schemes can outperform all the compared scheduling schemes.

A novel free space communication system using nonlinear InGaAsP microsystem resonators for enabling power-control toward smart cities

Nowadays, the smart grid has demonstrated a great ability to make life easier and more comfortable given recent advances. This paper studies the above issue from the perspective of two important and very useful smart grid applications, i.e., the advanced metering infrastructure and demand response using the instrumentality of a set of well-known scheduling algorithms, e.g., best-channel quality indicator, log rule, round robin, and exponential–proportional fairness to validate the performance. To increase the data transmission bandwidth, a new concept of optical wireless communication known as free-space optical communication (FSO) system based on microring resonator (MRR) with the ability to deliver up to gigabit (line of sight) transmission per second is proposed for the two studied smart grid applications. The range between 374.7 and 374.79 THz frequency band was chosen for the generation of 10 successive-carriers with a free spectral range of 8.87 GHz. The ten multi-carriers were produced through drop port of the MRR. The results show up to 10 times bandwidth improvement over the radius as large as 600 m and maintain receive power higher than the minimum threshold (− 20 dBm) at the controller/users, so the overall system is still able to detect the FSO signal and extract the original data without detection.

Exponential MLWDF (EXP-MLWDF) Downlink Scheduling Algorithm Evaluated in LTE for High Mobility and Dense Area Scenario

Nowadays, with the advent of smartphones, most of people started to make voice and video conference calls continuously even in a high mobility scenario, the bandwidth requirements have increased considerably, which can cause network congestion phenomena. To avoid network congestion problems and to support high mobility scenario, 3GPP has developed a new cellular standard based packet switching, termed LTE (Long Term Evolution). The purpose of this paper is to evaluate the performance of the new proposed algorithm, named Exponential Modified Largest Weighted Delay First ‘EXP-MLWDF’, for high mobility scenario and with the presence of a large number of active users, in comparison with the well-known algorithms such as a proportional fair algorithm (PF), Exponential Proportional Fairness (EXP/PF), Logarithm Rule (LOG-Rule), Exponential Rule (EXP-Rule) and Modified Largest Weighted Delay First (MLWDF). The performance evaluation is conducted in terms of system throughput, delay and PLR. Finally, it will be concluded that the proposed scheduler satisfies the quality of service (QoS) requirements of the real-time traffic in terms of packet loss ratio (PLR), average throughput and packet delay. Because of the traffic evolution, some key issues related to scheduling strategies that will be considered in the future requirements are discussed in this article.

Enabling remote-control for the power sub-stations over LTE-A networks

In recent years, smart grid (SG) applications have been proven a sophisticated technology of immense aptitude, comfort and efficiency not only for the power generation sectors but also for other industrial purposes. The term SG is used to describe a set of systems customized to rapidly and automatically monitor user demand, restore power, isolate faults and maintain stability for more efficient transmission, generation and delivery of electric power. Nevertheless, the quality of service (QoS) guarantee is essential to maintain the networking technology used in different stages and communication of the SG for efficient distribution, which may be drastically obstructed as the sensors of the application increases. Undoubtedly, receiving and transmitting of this information requires two-way, high speed, reliable and secure communication infrastructure. In this paper, we have proposed a scheduling approach guarantees the efficient utilization of existing network resources that satisfy the sensors’ demands sufficiently. The proposed approach is based on hierarchical adaptive weighting method, which helps to overcome the issues of studied scheduling approach and intended to aid SG sensors applications, based on its QoS demands. We have employed four enabler SG applications for remote power control, namely demand response, advanced metering infrastructure, video surveillance and wide area situational awareness applications for the implementation of the remote-power substation controlling. Moreover, the cooperative game theory technique has been incorporated into a solution for the optimal estimation and allocation of bandwidth among different sensors. The results have been evaluated in terms of throughput, fairness index and spectral efficiency and results have been compared with the well-known scheduling approaches such as exponential/proportional fairness (EXP/PF), best channel quality indicator (Best-CQI) and exponential rules (EXP-Rule). The results demonstrated that the proposed approach is providing a better performance in terms fairness index by 25, 66 and 68% compared to EXP/PF, EXP/RULE and Best-CQI, respectively.

New Combined Downlink Scheduling Algorithm for LTE Networks

Considered as the 4th generation network, the LTE (Long Term Evolution) was defined by the 3GPP consortium as a succession of these predecessors, allowing the improvement of the QoS offered to the customers. Due to the limitations at the bandwidth, Radio Resource Management (RRM) remains one of the important aspects in cellular networks. The Packet Scheduling is an essential mechanism of the RRM procedure. It is used to define the distribution method of radio resources. The main objective of these mechanisms is the improvement of the performance of the LTE system for all users. This is why scheduling algorithms are of great importance in the resources management. And since they are not defined in 3GPP specifications, they become a vital subject of research. In this paper, we proposed a new downlink scheduling algorithm named Combined PF-MLWDF-EXP/PF (CPMEP) and we compared its performances in a Single Cell with Interference scenario with the well-known schedulers such as Proportional Fair (PF), Modified Largest Weighted Delay First (MLWDF) and Exponential Proportional Fairness (EXP/PF). The simulation results show that the combined algorithm is more efficient for different applications, despite it has limitations in terms of Fairness Index and Throughput for Non Real-Time services.

LTE smart grid performance gains with additional remote antenna units via radio over fiber using a microring resonator system

Smart grid (SG) systems form the backbone of various services that provide comfort and efficiency enhancements. Increasing numbers of SG users cause additional demands by applications on the SG, and this trend eventually leads to the SG being unable to deliver services with sufficient quality. A system of optical and wireless access technologies, namely radio over fiber (RoF), is proposed here for adoption in SG systems (SG-RoF) in order to ensure provision of adequate capacity in line with transmission bandwidth service requirements. This paper details a microring resonator (MRR) system for use in SG-RoF systems, whereby the extra optical carriers are generated so as to increase the number of serviceable remote antenna units (RAUs). A number of very useful and widely used smart grid applications, namely video surveillances and advanced metering data, are also described in the context of the SG-RoF. The performance of well-known algorithms, such as proportional fairness, modified largest weighted delay first, exponential proportional fairness and exponential rule, are evaluated in this work to determine the optimal candidate for use in the proposed system.

COMPARATIVE ANALYSIS OF THE PERFORMANCE OF RESOURCE ALLOCATION ALGORITHMS IN LONG TERM EVOLUTION NETWORKS

The growth in the good number of real-time and non-real-time applications has sparked a renewed interest in exploring resource allocation schemes that can be efficient and fair to all the applications in overloaded scenarios. In this paper, the performance of six scheduling algorithms for Long Term Evolution (LTE) downlink networks were analyzed and compared. These algorithms are Proportional Fair (PF), Exponential/Proportional Fair (EXP/PF), Maximum Largest Weighted Delay First (MLWDF), Frame Level Scheduler (FLS), Exponential (EXP) rule and Logarithmic (LOG) rule. The performances of these algorithms were evaluated using an open source simulator (LTE simulator) and compared based on network parameters which include: throughput, delay, Packet Loss Ratio (PLR), and fairness. This work aims at giving insight on the gains made on radio resource scheduling for LTE network and to x-ray the issues that require improvement in order to provide better performance to the users. The results of this work show that FLS algorithm outperforms other algorithms in terms of delay, PLR, throughput, and fairness for VoIP and video flow. It was also observed that for Best Effort (BE) flows, FLS outperforms other algorithms in terms of delay and PLR but performed least in terms of throughput and fairness. http://dx.doi.org/10.4314/njt.v36i1.21

COMPARATIVE ANALYSIS OF THE PERFORMANCE OF RESOURCE ALLOCATION ALGORITHMS IN LONG TERM EVOLUTION NETWORKS

The growth in the good number of real-time and non-real-time applications has sparked a renewed interest in exploring resource allocation schemes that can be efficient and fair to all the applications in overloaded scenarios. In this paper, the performance of six scheduling algorithms for Long Term Evolution (LTE) downlink networks were analyzed and compared. These algorithms are Proportional Fair (PF), Exponential/Proportional Fair (EXP/PF), Maximum Largest Weighted Delay First (MLWDF), Frame Level Scheduler (FLS), Exponential (EXP) rule and Logarithmic (LOG) rule. The performances of these algorithms were evaluated using an open source simulator (LTE simulator) and compared based on network parameters which include: throughput, delay, Packet Loss Ratio (PLR), and fairness. This work aims at giving insight on the gains made on radio resource scheduling for LTE network and to x-ray the issues that require improvement in order to provide better performance to the users. The results of this work show that FLS algorithm outperforms other algorithms in terms of delay, PLR, throughput, and fairness for VoIP and video flow. It was also observed that for Best Effort (BE) flows, FLS outperforms other algorithms in terms of delay and PLR but performed least in terms of throughput and fairness. http://dx.doi.org/10.4314/njt.v36i1.21

PERFORMANCE ANALYSIS OF EXP-BET ALGORITHM FOR TRIPLE PLAY SERVICES IN LTE SYSTEM

Quality of Service (QoS) is defined as user’s satisfaction towards service performance that has been offered to them. Due to different traffic characteristics and QoS requirements of real-time and non-real-time services, thus provisioning the QoS requirements has become a challenge. In this study, we have compared our proposed algorithm namely the Exponential Blind Equal Throughput (EXP-BET) towards the Exponential Proportional Fairness (EXP-PF) and Frame Level Scheduler (FLS). The comparisons have been made in terms of fairness index, throughput,packet loss rate (PLR) and delay. From the simulation results, it is observed that EXP-BET delivers higher fairness and throughput and lower PLR and delay for real-time application. Instead, EXP-BET shows 17.72% improvement than FLS and 7.52% from EXP-PF in term of fairness index for the non-real-time application.

WE-MQS: A new LTE Downlink Scheduling Scheme for Voice Services based on User Perception

The Long Term Evolution (LTE) is a high data rates and fully All-IP network. Scheduling and resource allocation are very important tasks in LTE network. So that, the optimization of the real-time services transmission is very essential. However, there are many challenges when deploying the live multimedia services such as VoIP, Video, etc. This paper proposes a new scheduling scheme which based on the Wideband (WB) E-model, Channeland QoS-Aware (known as WE-MQS scheduler) for voice traffic in LTE downlink direction. The voice traffic flow is very sensitive to network impairments such as delay, packet loss, jitter, etc. The proposed scheduling scheme is based on the extension of the WB E-model and the consideration of Maximum Queue Size (MQS) as a factor for the metric. Since this scheduling scheme considers Mean Opinion Score (MOS) values, thus, it gets higher user perception. The simulation results show that the proposed scheme has the performance which not only satisfies QoS requirements of voice services but also outperforms well-known schedulers such as Frame Level Scheduler (FLS), Modified Largest Weighted Delay First (MLWDF) and Exponential/Proportional Fair (EXP/PF) schedulers in terms of delay for all the number of user (NU) and Packet Loss Rate (PLR) when the NU is more than 47. For the cell throughput, Fairness Index (FI), and Spectral Efficiency, the proposed scheduler is always in the middle of the remaining schedulers. The performance evaluation is compared in terms of Delay, PLR, Throughput, FI, and FI for FLS, M-LWDF, EXP/PF schedulers and the proposed one.

Enabling Remote Health-Caring Utilizing IoT Concept over LTE-Femtocell Networks.

As the enterprise of the “Internet of Things” is rapidly gaining widespread acceptance, sensors are being deployed in an unrestrained manner around the world to make efficient use of this new technological evolution. A recent survey has shown that sensor deployments over the past decade have increased significantly and has predicted an upsurge in the future growth rate. In health-care services, for instance, sensors are used as a key technology to enable Internet of Things oriented health-care monitoring systems. In this paper, we have proposed a two-stage fundamental approach to facilitate the implementation of such a system. In the first stage, sensors promptly gather together the particle measurements of an android application. Then, in the second stage, the collected data are sent over a Femto-LTE network following a new scheduling technique. The proposed scheduling strategy is used to send the data according to the application’s priority. The efficiency of the proposed technique is demonstrated by comparing it with that of well-known algorithms, namely, proportional fairness and exponential proportional fairness.

Comparative Analysis of Downlink Scheduling Algorithms for a Cell Affected by Interference in LTE Network

The main aim of long term evolution is to provide very high rate for downlink and uplink, better multimedia services and more user flexibility than the current cellular networks. There is a very important role of resource allocation management in the network to achieve better performance in terms of data rate and quality of service. These scheduling algorithms/strategies are responsible to allocating the resources to the users. There are many existing scheduling algorithms. In this paper we analyzed the performance of proportional fair, modified largest weighted delay first, exponential proportional fairness and FLS algorithms on a single cell affected by interference for different flows named as VIDEO, Best Effort, and CBR. The comparative analysis is done in terms of packet loss ratio, fairness index, delay, spectral efficiency and throughput.

A Pre-Scheduling Mechanism in LTE Handover for Streaming Video

This paper focuses on downlink packet scheduling for streaming video in Long Term Evolution (LTE). As a hard handover is adopted in LTE and has the period of breaking connection, it may cause a low user-perceived video quality. Therefore, we propose a handover prediction mechanism and a pre-scheduling mechanism to dynamically adjust the data rates of transmissions for providing a high quality of service (QoS) for streaming video before new connection establishment. Advantages of our method in comparison to the exponential/proportional fair (EXP/PF) scheme are shown through simulation experiments.

New Scheduling Algorithm Proposed for Real Time Traffic Over LTE Femto-Cell

Due to the inadequate indoor signal penetration, the indoor environment coverage becomes poor, which diminishes the quality of voice and video applications and slows down high-speed data services, which leads to customer churn, who expect high quality of service. To keep customers satisfied, Long Term Evolution (LTE) has developed a new advanced technology called FemtoCell, conceived to boost cellular network performance and is achieved with the use of access points installed by home users. The purpose of this paper is to analyze the performance of new proposed algorithm for voice and video over LTE FemtoCell, and to compare its performances with some well-known algorithms such as the proportional fair algorithm (PF), Exponential Proportional Fairness (EXP/PF), Logarithm Rule (LOG-Rule), Exponential Rule (EXP-Rule) and Modified Largest Weighted Delay First (MLWDF), The performance evaluation is conducted in terms of system throughput, delay, and Packet Loss Ratio. Finally it will be concluded that the proposed scheduler satisfies the quality of service (QoS) requirements of the real-time traffic in terms of packet loss ratio (PLR), average throughput and packet delay. This paper also discusses the key issues of scheduling algorithms to be considered in future traffic requirements.

A New Downlink Scheduling Algorithm Proposed for Real Time Traffic in LTE System

Abstract The Third Generation Partnership Project (3GPP) has developed a new cellular standard based packet switching allowing high data rate, 100 Mbps in Downlink and 50 Mbps in Uplink, and having the flexibility to be used in different bandwidths ranging from 1.4 MHz up to 20 MHz, this standard is termed LTE (Long Term Evolution). Radio Resource Management (RRM) procedure is one of the key design roles for improving LTE system performance, Packet scheduling is one of the RRM mechanisms and it is responsible for radio resources allocation, However, Scheduling algorithms are not defined in 3GPP specifications. Therefore, it gets a track interests for researchers. In this paper we proposed a new LTE scheduling algorithm and we compared its performances with other well known algorithms such as Proportional Fairness (PF), Modified Largest Weighted Delay First (MLWDF), and Exponential Proportional Fairness (EXPPF) in downlink direction. The simulation results shows that the proposed scheduler satisfies the quality of service (QoS) requirements of the real-time traffic in terms of packet loss ratio (PLR), average throughput and packet delay. This paper also discusses the key issues of scheduling algorithms to be considered in future traffic requirements.