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Sunhun Lee and Kwangsue ChungSchool of Electronics Engineering,
Kwangwoon University22nd International Conference on Advanced
Information Networking and Application
Joint Quality and Rate Adaptation Scheme for
Wireless Video Streaming
OutlineIntroductionBackgroundCross-layer designPerformance evaluationConclusion
IntroductionThis paper proposed a new cross-layer
design for video streaming over wireless network that jointly considers the application and the lower layers(PHY and MAC) to imporve the wireless link utilization by adapting the data transmission to the current channel condition.
Quality adaptation scheme – ApplicationRate adaptation scheme – MAC and PHY
BackgroundIEEE 802.11 WLAN
DCF (Distributed Coordination Function) – CSMA/CAPCF (Point Coordination Function) – pollingetc…(RTS/CTS)IEEE 802.11 PHY provides multiple data transmission
modes. (ex.1, 2, 5.5 and 11 Mbps are support at 2.4GHz
ISM band in 802.11b)
BackgroundIEEE 802.11 WLANRate adaptation scheme
Higher data rate does not yield a higher throughput.Basic idea of these scheme have been proposed is
to estimate the channel quality and adjust the data transmission mode accordingly.
1. Statistics-basedMaintain statistics about the data delivery such as
the PER/BER (Packet Error Rate / Bit Error Rate). o ARF (Auto Rate Fallback)o CARA (Collision-Aware Rate Adapation)
2. Quality-basedMeasure SNR (Signal to Noise Ratio) or SSI (Signal
Strength Indicator).o RBAR (Receiver-Based Auto Rate)
Cross-layer designOverview
Cross-layer designOverviewRate adaptation scheme in our design
This paper proposed a new scheme, called SARA (Sender-oriented Automatic Rate Adaptation)
Quality-basedRTS frame is used when the size of pending data is
equal to or larger than the RTS threshold.RSSI (Received Signal Strength Indicator) instead of
SNR
Cross-layer designOverviewRate adaptation scheme in our design
Cross-layer designOverviewRate adaptation scheme in our designQuality adaptation scheme in our design
Rate limit is calculated based on the packet pair algorithm and periodically notified to the quality of video stream.
Quality adaptation scheme uses the hierarchical encoding scheme, specifically the FGS (Fine Granularity Scheme) algorithm of MPEG-4 standards determined sending rate.
This paper think that the hierarchical encoding scheme is not employed to streaming application because encoders with this capability are rare.
Performance evaluationNS-2BSS mode (Include AP and Stations)CBR (Constant Bit Rate) traffic at a rate
4MbpsSimulation time 50s
10-30 low speed30-40 medium speed40-50 high speed
Performance evaluation
Performance evaluation
Performance evaluation
Performance evaluation
Performance evaluation
Performance evaluation
Performance evaluation
Quality adaptation
ConclusionThis paper proposed a idea that combines
the rate adaptation with the quality adaptation for providing improved wireless video streaming service.
In future, they want to extend their design to the wired-cum-wireless convergence network environments.