MECC scheduling algorithm in vehicular environment for uplink transmission in LTE networks

Single Carrier Frequency Division Multiple Access (SC-FDMA) is chosen because of the lower peak-to-average power ratio (PAPR) value in uplink transmission. However, the contiguity constraint is one of the major constraint presents in uplink packet scheduling, where all RBs allocated to a single UE must be contiguous in the frequency-domain within each time slot to maintain its single carrier. This paper proposed an uplink-scheduling algorithm namely the Maximum Expansion with Contiguity Constraints (MECC) algorithm, which supports both the RT and NRT services. The MECC algorithm is deployed in two stages. In the first stage, the RBs are allocated fairly among the UEs. The second stage allocates the RBs with the highest metric value and expands the allocation on both sides of the matrix, M with respect to the contiguity constraint. The performance of the MECC algorithm was observed in terms of throughput, fairness, delay, and Packet Loss Ratio (PLR) for VoIP, video and best effort flows. The MECC scheduling algorithm is compared to other algorithms namely the Round Robin (RR), Channel-Dependent First Maximum Expansion (CD-FME), and Proportional Fairness First Maximum Expansion (PF-FME). From here, it can be concluded that the MECC algorithm shows the best results among other algorithms by delivering the highest throughput which is up to 81.29% and 90.04% than CD-FME and RR scheduler for RT and NRT traffic respectively, having low PLR and delay which is up to 93.92% and 56.22% of improvement than CD-FME for the RT traffic flow. The MECC also has a satisfactory level of fairness for the cell-edge users in a vehicular environment of LTE network

Survey On Scheduling And Radio Resources Allocation In Lte

ABSTRACT This paper will center mainly on the PS part of the RRM task, which performs the radio resource allocation in both uplink and downlink directions. Several approaches and algorithms have been proposed in the literature to address this need (allocate resources efficiently), the diversity and multitude of algorithms is related to the factors considered for the optimal management of radio resource, specifically, the traffic type and the QoS (Quality of Service) requested by the UE. In this article, an art's state of the radio resource allocation strategies and a detailed study of several scheduling algorithms proposed for LTE (uplink and downlink) are made. Therefore, we offer our evaluation and criticism

Performances des algorithmes d’ordonnancement dans LTE Uplink

Dans cet article nous nous sommes intéressés à l’allocation des ressources radio dans les réseaux LTE (liaison montante Uplink) notamment avec une étude comparative entre quatre algorithmes d'ordonnancement des flux qui sont :Round Robin RR, First Maximum Expansion FME, Recursive Maximum Expansion RME et Improved Recursive Maximum Expansion IRME.Nous avons considéré les flux temps réel ou RT (Vidéo et VoIP), en considérant les critères de QoS : délai, efficacité spectral et débit.Les résultats obtenus montrent les avantages et les inconvénients de l'utilisation d'un algorithme par rapport à un autre

A new genetic algorithm based scheduling algorithm for the LTE Uplink

Tese (Doutorado)Long Term Evolution has become the de facto technology for the 4G networks. It aims to deliver unprecedented data transmission rates and low latency for several types of applications and services. In this context, this thesis investigates the resource allocation in the LTE uplink. From the principle that resource allocation in the uplink is a complex optimization problem, the main contribution of this thesis is a novel scheduling algorithm based on Genetic Algorithms (GA). This algorithm introduces new operations of initialization, crossover, mutation and a QoS-aware fitness function. The algorithm is evaluated in a mixed traffic environment and its performance is compared with relevant algorithms from the literature. Simulations were carried out in ns-3 and the results show that the proposed algorithm is able to meet the Quality of Service (QoS) requirements of the applications, while presenting a satisfactory execution time

A Novel HWRR-SJF Scheduling Algorithm for Optimal Performance Improvement in LTE System

In currently, the revolution in a high-speed broadband network is the requirement and also endless demand for high data rate and mobility. To achieve above requirement, the 3rd Generation Partnership Project (3GPP) has been established the Long Time Evolution (LTE). LTE has established an improved LTE radio interface named LTE-Advanced (LTE-A) and it is a promising technology for providing broadband, mobile Internet access. But, better Quality of Service (QoS) to provide for customers is the main issue in LTE-A. To reduce the above issue, the packets should be utilized by using one of the most significant function of packet scheduling to upgrading system performance via determines the throughput performance. In existing scheme, the user with poor Channel Quality Indicator (CQI) has smaller throughput issue is not focused. In this paper, a Hybrid Weighted Round Robin with Shortest Job First (HWRR-SJF) Scheduling technique is proposed to enhance efficient throughput and fairness in LTE system for stationary and mobile users. In this proposed scheduling, to schedule users according to a different criterion like fairness and CQI. HWRR-SJF Scheduling has been proposed for scheduling of the users and it produces increased throughput for various SNR values simulated alongside Pedestrian and Vehicular moving models. The proposed method also uses a 4G-LTE filter or Digital Dividend (DD) in order to align the incoming signal. The digital dividend is used to remove white spaces, which refer to frequencies assigned to a broadcasting service but not used locally. The proposed model is very effective for users in terms of the performance metrics like packet loss, throughput, packet delay, spectral efficiency, fairness and it has been verified through MATLAB simulations

Dynamic resource allocation algorithms for long term evolution (LTE) wireless broadband networks

Following the successful standardization of High-Speed Packet Access (HSPA), the 3rd Generation Partnership Project (3GPP) recently specified the Long Term Evolution (LTE) as a next generation radio network technology to meet the increasing performance requirements of mobile broadband. The results include a flexible and spectrally efficient radio link protocol design with low overhead. The first release of LTE provides peak rates of 300 Mbps in downlink and 75 Mbps in uplink. It is a significant increase in spectrum efficiency compared to the previous cellular systems. Single-Carrier Frequency Division Multiple Access (SC-FDMA) has been selected as the uplink access scheme in the LTE. With SC-FDMA, the frequency spectrum resource is divided into time-frequency grids, referred to as resource blocks (RBs). Multiple-access is achieved by distributing resource blocks to users. The function of resource block allocation algorithms is to distribute resource blocks among users in a fair and efficient manner. The Modulation and coding scheme is determined adaptively according to the time-varying channel conditions. Sounding Reference Signals (SRS) are transmitted in the uplink direction to allow for the base station to estimate the uplink channel quality at different frequencies. The LTE system supports wideband SRS and narrowband SRS. We have developed an in-house simulation program in C++ to evaluate and compare the performance of CASA and ICAS algorithms in terms of packet loss ratio, delay, and throughput. Simulation results show that the proposed algorithms are able to satisfy the QoS requirements. Both of proposed algorithms support multiple CoSs simultaneously without impeding the first class (Expedited Forwarding) transmission. Also, both of the proposed algorithms achieve high throughput in a large range cell

Adaptive channel estimation for LTE uplink

Third generation partnership project (3GPP) long term evolution (LTE) uses single carrier frequency division multiple access (SC-FDMA) in uplink transmission and orthogonal frequency division multiple access (OFDMA) scheme for the downlink. A variable step size based least mean squares (LMS) algorithm is formulated for a single carrier frequency division multiple access (SC-FDMA) system, in its channel estimation (CE). The weighting coefficients on the channel condition can be updated using this unbiased CE method. Channel and noise statistics information are not essential. Rather, it uses a phase weighting scheme to eliminate the signal fluctuations due to noise and decision errors. The convergence towards the true channel coefficient is guaranteed. The proposed algorithm is compared with the existing algorithms for BER and MSE performance in different channel environments

SC-FDMA-based resource allocation and power control scheme for D2D communication using LTE-A uplink resource

Device-to-device (D2D) communication-enabled cellular networks allow cellular devices to directly communicate with each other without any evolved NodeB (eNB). D2D communication aims to improve the spectral efficiency and increases the overall system capacity. For future mobile networks, intelligent radio resource allocation and power control schemes are required to accommodate the increasing number of cellular devices and their growing demand of data traffic. In this paper, a combined resource allocation and power control scheme for D2D communication is proposed. In the proposed scheme, D2D communication reuses the uplink (UL) resources of conventional cellular user equipments (CUEs); therefore, we have adopted single-carrier frequency division multiple access (SC-FDMA) as UL transmission scheme. The proposed scheme uses fractional frequency reuse (FFR)-based architecture to efficiently allocate the resources and mitigate the interference between CUEs and D2D user equipments (DUEs). In order to guarantee the user fairness, the proposed scheme uses the well-known proportional fair (PF) scheduling algorithm for resource allocation. We have also proposed an intelligent power control scheme which provides equal opportunity to both CUEs and DUEs to achieve a certain minimum signal-to-interference and noise ratio (SINR) value. The performance evaluation results show that the proposed scheme significantly improves the overall cell capacity and achieves low peak-to-average power ratio (PAPR)