44:. It is based upon maintaining a balance between two competing interests: Trying to maximize the total throughput of the network (wired or not) while at the same time allowing all users at least a minimal level of service. This is done by assigning each data flow a data rate or a scheduling priority (depending on the implementation) that is inversely proportional to its anticipated resource consumption.
771:
This technique can be further parametrized by using a "memory constant" that determines the period of time over which the station data rate used in calculating the priority function is averaged. A larger constant generally improves throughput at the expense of reduced short-term fairness.
376:
in the formula above, we are able to adjust the balance between serving the best mobiles (the ones in the best channel conditions) more often and serving the costly mobiles often enough that they have an acceptable level of performance.
432:) the scheduler acts in a "packet" round-robin fashion and serves all mobiles one after the other (but not equally often in time), with no regard for resource consumption, and such that each user gets the same amount of data. The (
194:
Another way to schedule data transfer that leads to similar results is through the use of prioritization coefficients. Here we schedule the channel for the station that has the maximum of the priority function:
716:) scheduler could be implemented by providing the same amount of time & spectrum for each user, irrespective of the desired packet size, channel quality and data rate (MCS) used. The proportional fair (
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Parruca, Donald; Grysla, Marius; Gortzen, Simon; Gross, James (2013), "Analytical Model of
Proportional Fair Scheduling in Interference-Limited OFDMA/LTE Networks",
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170:, the cost may be the required time to transmit a certain number of bits using the modulation and error coding scheme that this required. An example of this is
74:
185:, the cost may be the number of nearby base station sites that can not use the same frequency channel simultaneously, in view to avoid co-channel interference.
536:
then the scheduler will always serve the mobile with the best channel conditions. This will maximize the throughput of the channel while stations with low
966:; Kumaran, K.; Ramanan, K.; Stoyar, A.; Whitting, Phil (February 2001), "Providing Quality of Service over a Shared Wireless Link",
796:- a more general rule for selecting among different alternatives, based on the same principle of balancing efficiency and fairness.
484:) scheduler could be called "maximum fairness scheduler" (to be used to provide equal throughout to voice users for example). If
1063:
885:
Ji Yang; Zhang Yifan; Wang Ying; Zhang Ping (2004), "Average rate updating mechanism in proportional fair scheduler for HDR",
1022:
814:
Kushner, H. J.; Whiting, P.A. (July 2004), "Convergence of proportional-fair sharing algorithms under general conditions",
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17:
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864:, Jens Zander, Ki Won Sung, and Ben Slimane, Fundamentals of Mobile Data Networks, Cambridge University Press,
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768:) scheduler could be called "equal effort scheduler" or "time/spectrum Round Robin scheduler".
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924:(September 2004), "Instability of the Proportional Fair Scheduling Algorithm for HDR",
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denotes the data rate potentially achievable for the station in the present time slot.
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spread spectrum cellular networks, the cost may be the required energy per bit in the
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is the amount of consumed resources per data bit. For instance:
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Proportionally fair scheduling can be achieved by means of
989:
2013 IEEE 78th
Vehicular Technology Conference (VTC Fall)
986:
608:) scheduler could be called "max rate" scheduler. Using
56:(WFQ), by setting the scheduling weights for data flow
784:- an introduction to the general topic of scheduling.
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is the historical average data rate of this station.
238:{\displaystyle P={\frac {T^{\alpha }}{R^{\beta }}}}
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816:IEEE Transactions on Wireless Communications
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30:For the resource allocation problem, see
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178:is used as the primary costing factor.
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332:tune the "fairness" of the scheduler.
889:, vol. 6, pp. 3464–3466,
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790:- a different scheduling algorithm.
163:(the increased interference level).
24:
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25:
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660:will yield the proportional fair
27:Data network scheduling algorithm
627:{\displaystyle \alpha \approx 1}
653:{\displaystyle \beta \approx 1}
181:In wireless networks with fast
166:In wireless communication with
13:
1:
1064:Network scheduling algorithms
800:
117:{\displaystyle w_{i}=1/c_{i}}
1015:10.1109/VTCFall.2013.6692106
556:are not served at all. The (
38:Proportional-fair scheduling
7:
895:10.1109/GLOCOM.2004.1379010
775:
10:
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664:used in 3G networks. The (
183:Dynamic Channel Allocation
29:
1059:Mobile telecommunications
1049:Radio resource management
735:{\displaystyle \alpha =1}
683:{\displaystyle \alpha =1}
575:{\displaystyle \alpha =1}
503:{\displaystyle \alpha =1}
451:{\displaystyle \alpha =0}
399:{\displaystyle \alpha =0}
174:networks, where reported
761:{\displaystyle \beta =1}
709:{\displaystyle \beta =1}
601:{\displaystyle \beta =0}
529:{\displaystyle \beta =0}
477:{\displaystyle \beta =1}
425:{\displaystyle \beta =1}
1069:Fair division protocols
948:10.1109/TWC.2004.833419
838:10.1109/TWC.2004.830826
349:{\displaystyle \alpha }
305:{\displaystyle \alpha }
794:Proportional-fair rule
788:Round-robin scheduling
782:Scheduling (computing)
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32:Proportional division
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190:User prioritization
18:Proportionally fair
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549:{\displaystyle T}
283:{\displaystyle R}
261:{\displaystyle T}
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16:(Redirected from
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862:Guowang Miao
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1043:Categories
870:1107143217
801:References
998:1303.1778
934:CiteSeerX
824:CiteSeerX
750:β
724:α
698:β
672:α
645:≈
642:β
619:≈
616:α
590:β
564:α
518:β
492:α
466:β
440:α
414:β
388:α
364:β
344:α
320:β
300:α
229:β
219:α
1054:Wireless
956:34595035
776:See also
1033:8236469
1003:Bibcode
872:, 2016.
846:6780351
1031:
1021:
954:
936:
901:
868:
844:
826:
1029:S2CID
993:arXiv
952:S2CID
842:S2CID
1019:ISBN
899:ISBN
866:ISBN
742:and
690:and
634:and
582:and
510:and
458:and
406:and
356:and
312:and
172:EVDO
157:CDMA
1011:doi
976:doi
944:doi
891:doi
834:doi
176:SNR
155:In
76:to
1045::
1027:,
1017:,
1009:,
1001:,
972:39
970:,
950:,
942:,
928:,
897:,
877:^
854:^
840:,
832:,
818:,
1013::
1005::
995::
982:.
978::
958:.
946::
930:3
893::
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836::
820:3
756:1
753:=
730:1
727:=
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675:=
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593:=
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524:0
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495:=
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391:=
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256:T
225:R
215:T
209:=
206:P
137:i
133:c
110:i
106:c
101:/
97:1
94:=
89:i
85:w
64:i
34:.
20:)
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