scholarly journals Channel Aware Scheduling Algorithm for LTE Uplink and Downlink

2015 ◽  
Vol 7 (3) ◽  
pp. 111 ◽  
Author(s):  
Aswin Kanagasabai ◽  
Amiya Nayak
Keyword(s):  
Resource Allocation ◽  
Scheduling Algorithm ◽  
Vital Role ◽  
System Throughput ◽  
Proportional Fairness ◽  
Channel Condition ◽  
Allocation Process ◽  
Efficient Resource ◽  
Specific Implementation ◽  
Lte Uplink

In the past two decades, there has been a drastic increase in the mobile traffic, which is caused by the improved user experience with smart phones and its applications. In LTE system, the packet scheduler plays a vital role in the effective utilization of the resources. This field is not standardized and has immense scope of improvement, allowing vendor-specific implementation. LTE scheduling can be categorized into two extremes, namely, Opportunistic scheduling and Fairness scheduling. The Best Channel Quality Indicator (BCQI) algorithm falls under the former category while Proportional Fairness (PF) algorithm under the later. BCQI algorithm provides high system throughput than PF algorithm, however, unlike BCQI algorithm, PF algorithm considers users with poor channel condition for allocation process. In this work, a new scheduling algorithm called as Opportunistic Dual Metric (ODM) Scheduling Algorithm is proposed for LTE uplink and downlink.The objective of the algorithm is to prioritize the users with good channel condition for resource allocation, at the same time not to starve the users with poor channel conditions. The proposed algorithm has two resource allocation matrices, one being throughput-centric and the other being is fairness-centric. The uplink algorithm uses the two resource allocation matrices to allocate the resources to the users and to ensure contiguous resource allocation. The downlink algorithm is an extension of the proposed uplink algorithm avoiding uplink constraints. The downlink algorithm employs the two resource distribution matrices to provide an efficient resource allocation by expanding the allocation for the users considering intermittent resources. The performance of ODM is measured in terms of throughput, fairness. Additionally, the uplink algorithm is analyzed in terms of transmit power. From the results it is observed that the proposed algorithm has better trade-off in terms of all the performance parameters than PF scheduler and BCQI scheduler.

A Novel Proportional Fairness Scheduling for Subcarrier Allocation in OFDM Based Relaying Systems

2013 ◽  
Vol 765-767 ◽  
pp. 436-439
Author(s):  
Ya Ru Fu ◽  
Qi Zhu
Keyword(s):  
Communication Networks ◽  
Orthogonal Frequency Division Multiplexing ◽  
Transmission Rate ◽  
Scheduling Algorithm ◽  
Proportional Fairness ◽  
Wireless Communication Networks ◽  
Subcarrier Allocation ◽  
Frequency Division ◽  
Channel Condition ◽  
Relaying Systems

Different data rate services are expected to support for heterogeneous users in OFDM based relaying networks. And fairness of users is an important factor that cannot be neglected in the process of resource allocation, particularly for users at the cell edge. The traditional proportional fairness (PF) scheduling algorithm provides a trade-off between average throughout and fairness in wireless communication networks. This paper investigates subcarrier allocation problem of Orthogonal Frequency Division Multiplexing (OFDM) aided relaying systems with PF constraint and proposes an efficient PF scheduling priority by using the users channel condition of past scheduling time and current scheduling time more comprehensively and uniformly which can both maximize the system transmission rate and enhance the system fairness no less than traditional ones. The simulation results show the validity.

scholarly journals IEEE 802.11ax OFDMA Resource Allocation with Frequency-Selective Fading

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6099
Author(s):  
Sergei Tutelian ◽  
Dmitry Bankov ◽  
Dmitri Shmelkin ◽  
Evgeny Khorov
Keyword(s):  
Resource Allocation ◽  
Scheduling Algorithm ◽  
Access Point ◽  
Selective Fading ◽  
Resource Allocation Algorithm ◽  
Frequency Selective Fading ◽  
Ieee 802.11Ax ◽  
Channel Conditions ◽  
Efficient Resource ◽  
Frequency Selective

This paper studies the usage of orthogonal frequency division multiple access (OFDMA) for uplink transmissions in IEEE 802.11ax networks. OFDMA enables simultaneous multi-user transmissions in Wi-Fi, but its usage requires efficient resource allocation algorithms. These algorithms should be able to adapt to the changing channel conditions, including the frequency-selective fading. This paper presents an OFDMA resource allocation algorithm for channels with frequency-selective fading and proposes an approach to adapt the user transmission power and modulation and coding schemes to the varying channel conditions, which is efficient even in the case when the access point has outdated channel state information. The proposed scheduling algorithm and power allocation approach can double the goodput and halve the data transmission time in Wi-Fi networks even in dense deployments of access points.

Downlink and Uplink Resource Allocation in LTE Networks

2016 ◽  
pp. 199-233
Author(s):  
Johann Max Hofmann Magalhães ◽  
Saulo Henrique da Mata ◽  
Paulo Roberto Guardieiro
Keyword(s):  
Resource Allocation ◽  
Spectral Efficiency ◽  
Scheduling Algorithm ◽  
Scheduling Algorithms ◽  
Complex Task ◽  
Lte Networks ◽  
Allocation Process ◽  
High Spectral Efficiency ◽  
Resource Allocation Process

The design of a scheduling algorithm for LTE networks is a complex task, and it has proven to be one of the main challenges for LTE systems. There are many issues to be addressed in order to obtain a high spectral efficiency and to meet the application's QoS requirements. In this context, this chapter presents a study of the resource allocation process in LTE networks. This study starts with an overview of the main concepts involved in the LTE resource allocation, and brings two new proposals of scheduling algorithms for downlink and uplink, respectively. Simulations are used to compare the performance of these proposals with other scheduler proposals widely known and explored in the literature.

scholarly journals Comparison Study of Resource Allocation Strategies for OFDM Multimedia Networks

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Cédric Guéguen ◽  
Sébastien Baey
Keyword(s):  
Resource Allocation ◽  
Multipath Fading ◽  
System Throughput ◽  
Multimedia Networks ◽  
Channel State ◽  
Multimedia Services ◽  
Application Range ◽  
Time Frequency ◽  
Allocation Process ◽  
Allocation Strategies

Advanced MAC scheduling schemes provide efficient support of multimedia services in multiuser OFDM wireless networks. Designed in a cross layer approach, they opportunistically consider the channel state and are well adapted to the wireless multipath fading environment. These schedulers take advantage of time, frequency, and multiuser diversity. Thereby they maximize the global system throughput while ensuring the highest possible level of fairness. However their performances heavily depend on the bandwidth granularity (i.e., the number of elementary resource units) that is used in the resource allocation process. This paper presents and compares the main OFDM scheduling techniques. In particular it studies the influence of bandwidth granularity on the resource allocation strategies performances. The paper reveals that though bandwidth granularity has never been considered in former studies, it is of major importance for determining the application range of advanced OFDM scheduling techniques.

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