Article

A Selective Downlink Scheduling Algorithm to Enhance Quality of VOD Services for WAVE Networks

EURASIP Journal on Wireless Communications and Networking (Impact Factor: 0.72). 01/2009; 2009. DOI: 10.1155/2009/478157
Source: DBLP

ABSTRACT

Providing quality-of-service- (QoS-) guaranteed video on demand (VOD) services over wireless access in vehicular environments (WAVEs) is a challenge as WAVE adopts enhanced distributive channel access (EDCA), a contention-based channel access mechanism, for air interface access control. This paper proposes a selective downlink scheduling (SDS) algorithm to enhance the quality of VOD for WAVE networks. According to the importance of video decoding, video packets are categorized into high and low priorities. The categorized packets are put into different queues in roadside units (RSUs) to contend for transmission opportunities. Aiming to improve video playback quality and reduce video playback delay, the proposed SDS algorithm schedules video packets based on their importance, playback deadline, and their real-time parameters of receiving onboard units (OBUs), such as velocity and remaining dwelling time. The effectiveness of SDS algorithm is verified by simulations.

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    • "Several studies devise the QoS mechanisms [6] to provide guaranteed service to on-board passengers. [5] proposes a downlink scheduler to deliver high-quality video on demand services over V2I networks. The proposed scheduler is deployed at the RSU to coordinate the transmission of packets according to their importance to the video quality, playback deadline and the real-time information of vehicles such as the velocity, link quality and sojourn time in the RSU. "
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    • "Analysis in[4]and[5]presents performance results for heartbeat broadcasts which relate node populations and probability of frame collisions when ackowledgements are not present. Recent works have also analyzed features and requirements of in-vehicle comfort and infotainment applications[6],[7]. In this work we combine M/G/1 queuing analysis and Markov chain analysis partly used in our previous work on non-saturation analysis[9]In this work we consider the neighborhood of single Roadside Unit RSU operating in non-saturation regime. "

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