A proportional fair scheduling algorithm based on qos. In this paper we explore this fundamental problem of lte scfdma uplink scheduling by adopting the conventional timedomain proportional fair algorithm to maximize its objective i. They exploit the users channel state diversity induced by fastfading, and are optimal for stationary channel state distributions and an in. An opportunistic feedback technique is proposed for proportional fair pf scheduling in a downlink multiuser system. Consider a model where there are n active users sharing a wireless channel with the channel condition. Trying to maximize total throughput of the network wired or not while at the same time allowing all users at least a minimal level of service.
User fairness scheme with proportional fair scheduling in. The proportional fair pf scheduling technique is well known technique that is used to schedule radio resources at the mobile base station to the endusers. Pdf the weighted proportional fair scheduler eitan altman. Nov 15, 2012 the optimal power allocation parameters of each sc layer are derived by analysis. In this paper, we determine the strength of the effect of feedback delay on the scheduler in a longterm evolution lte system. The selection of the user to schedule is based on a balance between the current possible rates and fairness.
In a practical wireless system, a greedy algorithm that selects the user with the best channel. Analytical insight under rayleigh fading environment. Enhanced throughput and fairness in lte dl mahir ayhan. Considering firstly a twouser relay broadcast channel, we design a scheme based on superposition coding sc which maximizes the achievable sumrate under a proportional fairness constraint. We study this degradation under fairness constraints using a proportional fair scheduler. Proportionalfair resource allocation for coordinated. I would also be glad if the same terminology was used to explain the difference between proportional fair, maxmin fairness, maximum throughput scheduling and channeldependent scheduling. Qosaware proportional fair qapf downlink scheduling algorithm for lte network 1zin mar myo, 2myat thida mon 1,2university of computer studies, yangon email. The worstcase single packet delay of bsfq is proportional to the number of o ws. Performance comparison between round robin and proportional. Pdf in this work we consider the problem of downlink re source allocation for proportional fairness of long term received rates of data users and. Abstractproportional fair pf scheduling algorithms are the defacto standard in cellular networks.
Pdf the weighted proportional fair scheduler eitan. Proportional fair scheduling with superposition coding in a. Aug, 2019 in practical communication systems, there are always multiple subscribers competing for limited resources, such as time and frequency, hence effective user scheduling is essential to multiuser communications in achieving good system throughput and fairness performance. Proportional fair scheduling algorithm proportional fair is used mostly in wireless networks. Utilizing geometric mean in proportional fair scheduling. The proportional fair scheduling pfs algorithm is considered an attractive bandwidth allocation criterion in wireless networks for supporting high resource utilization while maintaining good fairness among network flows. Wo2019192307a1 proportional fair scheduling implementation.
We apply proportional fair pf, round robin rr and modifiedpf scheduling algorithm for lte in order to find the best scheduler which provides. Performance evaluation of proportional fairness scheduling. Performance of proportional fairness scheduling pfs 1 and. It is based upon maintaining a balance between two competing interests. An efficient scheduling for radio resources in the physical layer of ltea base stations is challenging due to the high demand for various types of 4g. An efficient scheduling for radio resources in the physical layer of ltea base stations is. Note that having an o1 gpsrelative delay is not suf. In this paper, we consider the effects of scheduling algorithms on the throughput performance.
The most commonly used and powerful scheduling algorithm in ltea is proportional fair 12. Proportional fair multiuser scheduling in lte request pdf. Qosaware proportional fair qapf downlink scheduling algorithm for lte network proceedings of seventh theiier international conference, singapore, 3rd january 2015, isbn. In case of transmit diversity, an improvement of signal to noise ratio is obvious. Coordinated multipoint comp transmission and reception are introduced as a promising technology in the 3gpp lteadvanced standard, to manage interference, improve the overall system performance, and enhance system reliability. Weighted proportional fair scheduling for downlink nonorthogonal multiple access marierita hojeij, student member, ieee, charbel abdel nour, member, ieee, joumana farah, member, ieee, and catherine douillard, senior member, ieee abstractin this paper, a weighted proportional fair pf scheduling method is proposed in the context of non. Ofdma represents a promising multiple access scheme for transmission over wireless channels, as it combines the orthogonal frequency division multiplexing ofdm modulation and subcarrier. Proportional fair scheduling algorithm based on traffic in. Lottery scheduling p the scheduler picks a winning ticket. In 20, a weighted pf algorithm is proposed in order to maximize best. Hybrid scheduling schemes 14, 15 have also been proposed. However, with the deployment of new technologies, such as hdr high date rate and hsdpa high speed downlink packet access, this situation is bound to evolve rapidly and. Pdf proportional fair scheduling algorithm in ofdmabased.
Proportional fair is a compromisebased scheduling algorithm. Generalized proportional fair scheduling in third generation. In 3g data networks, network operators would like to balance system throughput while serving users in a fair manner. Proportional fair resource allocation also corresponds to an allocation that maximizes the sum of logarithms of received rates 5.
May 22, 2017 in order to reduce these collisions, we propose and evaluate through simulations a novel scheduling algorithm, called neighboraware proportional fair npf, which takes into account both channel state conditions and the number of uncoordinated nodes neighboring each scheduled node in the aggregate scheduling metric. Analytical evaluation of the performance of proportional. In practical communication systems, there are always multiple subscribers competing for limited resources, such as time and frequency, hence effective user scheduling is essential to multiuser communications in achieving good system throughput and fairness performance. A forward link, which can make a degree of balance between fairness and throughput. In cdma spread spectrum cellular networks, the cost may be the required energy per bit in the transmit power control the.
It was first presented in codedivision multiple access high datarates cdmahdr 15, 16, but is now used extensively in ofdma based systems as well. Proportional fair scheduling was recently studied for multi. Proportional fair scheduling with superposition coding in. A proportional fair scheduling algorithm pf provides balance between fairness and the overall system throughput. A proportional fair scheduling algorithm based on qos utility. The user with the highest metric is allocated the resource available in the given interval, the metrics for all users are updated before the next scheduling interval, and the process repeats. User fairness scheme with proportional fair scheduling in multiuser mimo limited feedback system. The conventional proportional fair pf scheduling achieves fairness at the cost. The weighted proportional fair scheduler proceedings of. Neighborsaware proportional fair scheduling for future. Proportional fair pf scheduling algorithms are the defacto standard for opportunistic schedulers in cellular networks. Proportional fair frequencydomain packet scheduling for 3gpp lte uplink sukbok lee. School of electronics and information engineering, harbin institute of technology, harbin, china.
This is achieved using the notion of proportional fairness. The most challenge of a pfs problem is the lack of analytic expression. Proportional share scheduling of operating system services. A proportional fair schedule is such that any positive change of a user in rate allocation must result in a negative overall change in the system. Lte proportional fair scheduling free open source codes. While the algorithm components of these schemes are similar to those.
Such an approach can result in nonpareto optimal bandwidth allocation when considering the network. How are the wfq weights and the priority function related to each other. This paper provides an analytical evaluation of the performance of proportional fair pf scheduling in orthogonal frequencydivision multiple access ofdma wireless systems. The weighted proportional fair scheduler proceedings of the. In order to reduce these collisions, we propose and evaluate through simulations a novel scheduling algorithm, called neighboraware proportional fair npf, which takes into account both channel state conditions and the number of uncoordinated nodes neighboring each scheduled node in the aggregate scheduling metric. Proportionally fair scheduling can be achieved by means of weighted fair queuing wfq, by setting the scheduling weights for data flow to, where the cost is the amount of consumed resources per data bit. An apparatus for implementing a proportional fair scheduling, wherein the apparatus comprises. Proposed scheduling algorithm the main important role of the scheduler is the allocation of resources to ues at each time slot to achieve maximization in throughput and fairness for each user. This solution was shown to achieve both high capacity and high fairness. Proportional fair frequencydomain packet scheduling for 3gpp.
Request pdf proportional fair multiuser scheduling in lte the challenge of scheduling user transmissions on the downlink of a long term evolution lte cellular communication system is addressed. Using the channel state information csi from the receiver, the opportunistic pf scheduling pfs algorithm for wireless networks was proposed in 4. In broadband wireless access systems proportional fairness maintains a good tradeoff between spectral efficiency and fair ness. Bei yang, kai niu, zhiqiang he, wenjun xu, and yingpei. The algorithm tries is provide fairness among ues while maximizing the. Enhanced proportional fair scheduling for cdma2000 1x ev. We show the nphardness of the frequencydomain scheduling. Pdf performance comparison between round robin and. Consider a model where there are active users sharing a wireless channel with the channel condition seen. In 46 proposed proportional fair pf scheduling algorithm that exploits the multiuser diversity to achieve fairness among users without. Rr algorithm gives equal scheduling chance to each user in the cell, whereas pf. In case of long term evolution lte, the scheduler in the mac layer of the enodeb allocates the available radio resources among different ues in a cell through proper handling of priority. Weighted proportional fair scheduling for downlink.
Currently, the classic scheduling algorithms are mainly round scheduling round robin, rr algorithm 7, the maximum carrier to interference scheduling max carrier to interference, max ci algorithm 8, proportional fair scheduling proportional fair, pf algorithm 10. Disclosed in the present application are a proportional fair pf scheduling implementation method and apparatus, and a device and a computerreadable storage medium. The distinguishing value of the proposal resides in its. Proportional fair scheduling in hierarchical modulation aided. However, so far, proportional fairness has been applied at each base station independently. Rr algorithm gives equal scheduling chance to each. Reduction of the feedback delay effect on a proportional fair. Throughput analysis of the proportional fair scheduler in. Ioannis pefkianakis adam meyerson shugong xu songwu lu. However, since a realistic deployment of wireless lans can consist of a network of aps, this paper considers proportional fairness in this much wider setting. The proportional fair scheduling pfs algorithm 2 4 9. There should be an article on scheduling communication. Pdf proportional fair scheduling algorithm in ofdma.
Analytical evaluation of the performance of proportional fair. Thus, at the cell edge, a combination of round robin and transmit diversity achieves very good data rate. Proportionalfair resource allocation for coordinated multipoint transmission in lteadvanced abstract. Computer science department huawei technologies ucla, ca 90095 shanghai, china abstractwith the power consumption issue of mobile handset taken into account, singlecarrier fdma scfdma has been. The scheduling of mobile users often relies on accurate feedback from the channel quality indicator cqi. Next, we consider the general multiuser case in a cellular relay system, for which we design resource allocation algorithms based on proportional fair scheduling exploiting the proposed scbased scheme. These novel technologies implement opportunistic scheduling, taking advantage of the delaytolerance of elastic traffic, to augment the global capacity of the system. Abstract to this day, traffic in cellular networks is still mainly realtime. Proportionalfair resource allocation for coordinated multi. Weighted proportional fair scheduling for downlink non. Throughput analysis of the proportional fair scheduler in hsdpa.
Pf scheduling algorithms have been extensively studied in the past e. The scheduling algorithm running in the base station for the downlink can quickly adapt to fading channel conditions thanks to the feedback of the channel states. Proportional fair scheduling in a wireless network, as the channels of different users are independent and heterogeneous, opportunistic scheduling was proposed to exploit the multiuser diversity gain to improve system ef. In this paper, we analyzed the performances of round robin and proportional fair scheduling methods for two different. Previous work has shown that proportional fair pf is an opportunistic scheduler that provides a good compromise between fairness and efficiency. This technique requires each mobile station, the scheduling metric of which is higher than a threshold, to send onebit feedback for pf scheduling. Exploiting mobility in proportional fair cellular scheduling. Performance evaluation of proportional fairness scheduling in lte.
At each scheduling instance, the priority of user i, ri, is calculated based on the users. Lte mac scheduler analysis based on qos aware proportional. We show how a monolithic, singlethreaded operating system kernel such as the freebsd kernel can be extended to allow proportional share execution of network packet and protocol processing. Various scheduling strategies have been implemented in ofdma systems. Scheduling algorithm an overview sciencedirect topics.
Proportional fair is a channelstate based scheduling algorithm that relies on the concept of exploiting user diversity. The new scheme introduces weights that adapt the classical pf metric to the noma scenario, improving performance indicators and enabling new services. Lottery fairness study to make this process most ef. The lte link level simulator simulator is provided with a test simulation scenario that can be used to verify that the simulator runs in the expected way. Improved proportional fair scheduling algorithm in. These schedulers intend for gbr services by taking into not only channel condition but. Proportional fair resource allocation for coordinated multipoint transmission in lteadvanced abstract. In the satellite communication network system, in order to solve the problem of low system capacity and user fairness in multiuser access to satellite communication network in the downlink, combined with the characteristics of user data service, an algorithm study on throughput capacity and user fairness scheduling is proposed proportional fairness algorithm based on trafficbpf. The basic algorithm the proportional fair algorithm is a packet scheduling method that provides reasonable level of fairness to the users and in the same time it is able to achieve high overall throughput. For example, a maximum rate scheduling is demonstrated to enhance both system throughput and fairness in multicarrier ofdma systems 3. Request pdf proportional fair multiuser scheduling in lte the challenge of scheduling user transmissions on the downlink of a long term evolution lte cellular communication system is. Bin sort fair queuing bsfq 4 uses an approximate bin sort mechanism to schedule packets.
They aim to provide high throughput while maintaining fairness among the users. Reduction of the feedback delay effect on a proportional. This script provides a means to test the performance of an lte. A weighted proportional fair pf scheduling method is proposed in the context of nonorthogonal multiple access noma with successive interference cancellation sic at the receiver side. Performance study of round robin and proportional fair. In the satellite communication network system, in order to solve the problem of low system capacity and user fairness in multiuser access to satellite communication network in the downlink, combined with the characteristics of user data service, an algorithm study on throughput capacity and user fairness scheduling is proposed proportional fairness. Introduction cellular networks are facing a considerable increase in mobile data traf. In our work, we propose a novel algorithm for scheduling of downlink resources with the objective of overcoming the performance limits of the wellknown existing solutions. Currently, proportional fair scheduling is adopted in cdma2000 1x evdo rev. The scheduler determines the optimal modulation and coding scheme for a scheduled user. Improved proportional fair scheduling algorithm in lte. Proportional fair frequencydomain packet scheduling for.
Proportional fair scheduling algorithm in ofdmabased wireless systems with qos constraints article pdf available in journal of communications and networks 121. Also, it is the most powerful algorithm used in ltea because, it can work based on maintaining a balance between throughput and fairness for. Analytical model of proportional fair scheduling in. Ofdma represents a promising multiple access scheme for transmission over wireless channels, as it combines the orthogonal frequency division multiplexing ofdm modulation and subcarrier allocation. Adaptive proportional fair scheduling with globalfairness. Quadratic proportional fair scheduling algorithm for ltea. The scheduling method used largely impacts the throughput. The proportional fair scheduling algorithm calculates a metric for all active users for a given scheduling interval.