arq aware scheduling for the ieee 802.16 base station
Post on 02-Jan-2016
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ARQ Aware Scheduling for the IEEE 802.16 Base StationARQ Aware Scheduling for the IEEE 802.16 Base Station
Alexander Sayenko
Nokia Research Center
Helsinki, Finland
Olli Alanen and Timo Hamalainen
Telecommunication laboratory, MIT department,
University of Jyvaskyla, Finland
ICC 2008
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OutlineOutline
IntroductionARQ Aware SchedulingSimulationConclusions
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IntroductionIntroduction
IEEE 802.16, called WiMAX Point-to-MultiPoint (PMP)
BSSS
Automatic Repeat Request (ARQ) Retransmission
MAC protocol data unit (PDU)
BSBSBSBS
SSSSSSSS SSSSSSSS SSSSSSSS
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IntroductionIntroduction
ARQ aware scheduling for the 802.16 BS ARQ block size ARQ transmission window ARQ block rearrangement
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ARQ Aware SchedulingA. Basics of the 802.16 ARQ mechanismARQ Aware SchedulingA. Basics of the 802.16 ARQ mechanism
If ARQ is enabled for a connection General MAC header (GMH)
Extended fragmentation subheader (FSH)Extended packing subheader (PSH)
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ARQ Aware SchedulingA. Basics of the 802.16 ARQ mechanismARQ Aware SchedulingA. Basics of the 802.16 ARQ mechanism
Subheader Block Sequence Number (BSN)
indicates the first ARQ block number in the PDU
BSN
?802.16d 802.16e
1~2040 bytes 16~1024 bytese.g.,16, 32, 64 …
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ARQ Aware SchedulingB. Basics of the 802.16 schedulingARQ Aware SchedulingB. Basics of the 802.16 scheduling
minimum (Ni
min )
maximum (Ni
max )
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ARQ Aware SchedulingC. ARQ block sizeARQ Aware SchedulingC. ARQ block size
SGMH: GMH size (6 bytes) SFSH : FSH size (2 bytes for the ARQ enabled connection)
SiARQ: the ith connection ARQ block size
SCRC : CRC field size (4 bytes)
Si : slot size (by modulation and coding scheme (MCS))
Uplink connection:+ GMSH size (2 byte)
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ARQ Aware SchedulingD. ARQ transmission windowARQ Aware SchedulingD. ARQ transmission window
SiARQ: the ith connection ARQ block size
Wi : the ARQ transmission window size
FPS : the number of frames per second
DF : the delay factor
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ARQ Aware SchedulingD. ARQ transmission windowARQ Aware SchedulingD. ARQ transmission window
SGMH: GMH size (6 bytes) SFSH : FSH size (2 bytes for the ARQ enabled connection) Si
ARQ: the ith connection ARQ block size Wi : the ARQ transmission window size SCRC : CRC field size (4 bytes) Si : slot size (by modulation and coding scheme (MCS))
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ARQ Aware SchedulingE. ARQ block rearrangementARQ Aware SchedulingE. ARQ block rearrangement
if the BS knows that an SS does not support ARQ block rearrangement
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ARQ Aware SchedulingF. SS uplink schedulerARQ Aware SchedulingF. SS uplink scheduler
BSBSBSBS
SSSS11SSSS11 SSSSmmSSSSmm
CC11CC11 CC22CC22 CCnnCCnn
SSSS22SSSS22
CID
Connection:
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SimulationSimulation NS-2 simulator :802.16 MAC and PHY levels MAC
Frames Bursts Downlink and uplink transmission Connections MAC PDUs
Packing and fragmentation Contention and ranging periods MAC level management messages Dynamic size of the MAP messages ARQ mechanism
ARQ blocks, ARQ transmission window Retransmission with rearrangement All the ARQ feedback types
PHY OFDMa
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SimulationSimulation
Network structure
1 UL BE connection
1 DL BE connection
FTP-like application
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SimulationSimulation
Fixed
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SimulationSimulation
Each simulation lasts for 10 seconds
Applications start to transmit data at the 1.5th second of a simulation run
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SimulationA. ARQ block sizeSimulationA. ARQ block size
Downlink
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SimulationA. ARQ block sizeSimulationA. ARQ block size
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SimulationB. ARQ block rearrangementSimulationB. ARQ block rearrangement
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SimulationB. ARQ block rearrangementSimulationB. ARQ block rearrangement
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SimulationC. ARQ transmission windowSimulationC. ARQ transmission window
ARQ block size is 16 bytes
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SimulationC. ARQ transmission windowSimulationC. ARQ transmission window
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ConclusionsConclusions
ARQ aware resource allocation in the 802.16 networks ARQ block size ARQ transmission window ARQ block rearrangement
A better performance can be achieved Larger ARQ block sizes Create large PDUs Dropped UGS and rtPS classes vs. nrtPS and BE classes
Smaller ARQ block sizes vs. Larger ARQ block sizes
ARQ transmission window To avoid wasting resources on connections
ARQ block rearrangement
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Thank You
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