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29
A Performance Study of Uplink Scheduling Algorithms in Point to Multipoint WiMAX Networks
, 2007
"... Applications such as video and audio streaming, online gaming, video conferencing, Voice over IP (VoIP) and File Transfer Protocol (FTP) demand a wide range of QoS requirements such as bandwidth and delay. Existing wireless technologies that can satisfy the requirements of heterogeneous traffic are ..."
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Applications such as video and audio streaming, online gaming, video conferencing, Voice over IP (VoIP) and File Transfer Protocol (FTP) demand a wide range of QoS requirements such as bandwidth and delay. Existing wireless technologies that can satisfy the requirements of heterogeneous traffic are very costly to deploy in rural areas and “last mile ” access. Worldwide Interoperability for Microwave Access (WiMAX) provides an affordable alternative for wireless broadband access supporting a multiplicity of applications. The IEEE 802.16 standard provides specification for the Medium Access Control (MAC) and Physical (PHY) layers for WiMAX. A critical part of the MAC layer specification is scheduling, which resolves contention for bandwidth and determines the transmission order of users. It is imperative for a scheduling algorithm to have a multi-dimensional objective of satisfying QoS requirements of the users, maximizing system utilization and ensuring fairness among the users. In this thesis, we categorize and study various scheduling algorithms for the uplink traffic in WiMAX in view of these objectives. The algorithms
Semi-reliable Transport Protocol for IPTV over
"... Abstract—As Internet IPTV extends to mobile devices, suitable transport protocols are sought that can adapt streaming to wireless access networks. This paper proposes a semi-reliable video-rate protocol that provides selective retransmission of scalable video layers should channel packet loss occur. ..."
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Abstract—As Internet IPTV extends to mobile devices, suitable transport protocols are sought that can adapt streaming to wireless access networks. This paper proposes a semi-reliable video-rate protocol that provides selective retransmission of scalable video layers should channel packet loss occur. The semi-reliable protocol leads to good video quality but reduces end-to-end delay and start-up delay. Keywords- error resiliency; H.264/SVC; mobile TV; transport protocols I.
An Improved IEEE 802.16 WiMAX Module for the NS-3 Simulator
"... IEEE 802.16 WiMAX is a promising new wireless technology for providing broadband ubiquitous network access. As more and more researchers and industrials are interested in simulating such networks, a number of WiMAX simulators have been emerged in the networking community. One of the most recent WiMA ..."
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IEEE 802.16 WiMAX is a promising new wireless technology for providing broadband ubiquitous network access. As more and more researchers and industrials are interested in simulating such networks, a number of WiMAX simulators have been emerged in the networking community. One of the most recent WiMAX simulator is the one developed for ns-3. This module provides a standard compliant and well designed implementation of the standard and benefits from the major enhancements provided by ns-3 (compared to other network simulators) which has all the capabilities of becoming the leading network simulator in near future. However, this WiMAX module still lacks some important features which motivated this work. In this paper, we first provide a snapshot of existing WiMAX simulators available in the public domain, while highlighting their limitations. Then, we describe the new features and enhancements we have integrated within the ns-3 WiMAX module, and in particular: a realistic and scalable physical model, an IP packet classifier for the convergence sub-layer, efficient uplink and downlink schedulers, support for multicast traffic and pcap packet tracing functionality. The new design of the physical layer has improved the simulation time by several magnitude orders while still providing a realistic implementation of the standard. Furthermore, the IP classifier has enabled the simulation of an unlimited number of service flows per subscriber station, while the proposed schedulers improve the management of the QoS requirements for the different service flows.
Options for WiMAX Uplink Media Streaming
"... IEEE 802.16e (mobile WiMAX) uplink behavior is a relatively neglected area of investigation, but emerging interactive media services have highlighted the need for closer investigation of uplink issues. In this simulation study of uplink queue management, media streaming by TCP-Friendly Rate Control ..."
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IEEE 802.16e (mobile WiMAX) uplink behavior is a relatively neglected area of investigation, but emerging interactive media services have highlighted the need for closer investigation of uplink issues. In this simulation study of uplink queue management, media streaming by TCP-Friendly Rate Control (TFRC) was found to offer advantages. However, temporal behavior of the queuing disciplines exhibits oscillations in buffer occupancy with build-up of delay during video streaming. The paper suggests a possible remedy lies in the choice of the more complex H.264/AVC Main profile, though this will impact upon mobile devices. It was also found that WiMAX video delivery is sensitive to choice of transmission frame size.
Optimal Rate Allocation for Scalable Video Multicast over WiMAX
"... Abstract—The IEEE 802.16 standard (commonly known as WiMAX), which has been proposed as a new wireless broadband standard, is capable of delivering very high data rate and covering wide area. Video multicast service would become one potential application over WiMAX with the popularity of streaming a ..."
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Abstract—The IEEE 802.16 standard (commonly known as WiMAX), which has been proposed as a new wireless broadband standard, is capable of delivering very high data rate and covering wide area. Video multicast service would become one potential application over WiMAX with the popularity of streaming applications in the Internet. Our method mainly uses adaptive modulation to achieve the goal of rate-adaptive multicast, and combines with the concept of layered multicast. According to the size of video layer, SS distribution, and available symbols, our method adaptively changes the modulations of each video layer in each group of picture (GOP) time. We also propose a Genetic Algorithm (GA) to reduce computational complexity when finding optimal modulation. Experimental results show that the proposed method can achieve promising performance. I.
Robust IPTV Delivery with Adaptive Rateless Coding over a Mobile WiMAX Channel
"... ABSTRACT—As intelligent content management of IPTV moves popular material nearer to the end-user, applicationlayer channel coding schemes, involving retransmission of extra redundant data, become attractive as a result of the reduced latency. Application-layer, adaptive rateless channel coding is ex ..."
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ABSTRACT—As intelligent content management of IPTV moves popular material nearer to the end-user, applicationlayer channel coding schemes, involving retransmission of extra redundant data, become attractive as a result of the reduced latency. Application-layer, adaptive rateless channel coding is exploited in this paper’s scheme to reconstruct streamed video across an IEEE 802.16e (mobile WiMAX) channel. The paper concentrates on the trade-offs in implementing the scheme, showing that exact calculation of the redundant data has the potential to reduce the forward error correction bit-rate overhead. To reduce delay, an appropriate compression rate should also be selected. I.
Protection Modes for Segmented Video Streaming over Broadband Wireless
"... Abstract—Segmented or data-partitioned H.264/AVC codec video streaming separates-out important information from the compressed bitstream and places it into separate packets. Because of the damaging impact of error bursts on real-time video streams, it has become common to apply application-layer for ..."
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Abstract—Segmented or data-partitioned H.264/AVC codec video streaming separates-out important information from the compressed bitstream and places it into separate packets. Because of the damaging impact of error bursts on real-time video streams, it has become common to apply application-layer forward error correction (FEC) for transport over broadband wireless access networks, herein IEEE 802.16e. In this paper an adaptive FEC scheme using Raptor coding is applied to segmented video. The paper sets out to answer the question whether equal or unequal error protection is preferable in that situation. Though UEP offers a reduction in bitrate there are multiple dB gains in video quality, which will prove attractive to end-users, if equal error protection is provided. Overhead from using EEP rather than UEP was found to be about 1 % of the overall bitrate. Keywords-data-partitioning; equal error protection; IEEE 802.16e; unequal error protection; video streaming; WiMAX I.
2012 The Society for Modeling and Simulation International
"... sim.sagepub.com Simulation of points of interest distribution in vehicular networks ..."
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sim.sagepub.com Simulation of points of interest distribution in vehicular networks
Error Resilient IPTV for an IEEE 802.16e Channel
"... Data-partitioning of IPTV video streams is a way of providing graceful quality degradation in a form that will work in good and difficult wireless channel conditions, as experienced by mobile devices. This paper’s proposal is to combine redundant slice protection along with an adaptive channel codin ..."
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Data-partitioning of IPTV video streams is a way of providing graceful quality degradation in a form that will work in good and difficult wireless channel conditions, as experienced by mobile devices. This paper’s proposal is to combine redundant slice protection along with an adaptive channel coding scheme that is also proposed in the paper. Adaptive channel coding is achieved by retransmission when necessary of additional redundant data to reconstruct corrupted packets. In the proposal, outright packet loss is provided for by a form of redundant slice protection. The paper finds that it is preferable: not to simply protect only the highest priority packets; that a moderate quantization level should be employed; and that video quality is differentiated by content type. It is important also to configure the partitioning correctly to remove inter-partition dependencies when possible.
Impact of Modeling Different Fading Channels on Wireless MAN Fixed IEEE802.16d OFDM System with Diversity Transmission Technique
"... is a promising technology which can offer high speed data, voice and video service to the customer end, which is presently, dominated by the cable and digital subscriber line (DSL) technologies. The performance assessment of Wimax systems is dealt with. The biggest advantage of Broadband wireless ap ..."
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is a promising technology which can offer high speed data, voice and video service to the customer end, which is presently, dominated by the cable and digital subscriber line (DSL) technologies. The performance assessment of Wimax systems is dealt with. The biggest advantage of Broadband wireless application (BWA) over its wired competitors is its increased capacity and ease of deployment. The aims of this paper are to model and simulate the fixed OFDM IEEE 802.16d physical layer under variant combinations of digital modulation (BPSK, QPSK, and 16-QAM) over diverse combination of fading channels (AWGN, SUIs). Stanford University Interim (SUI) Channel serial was proposed to simulate the fixed broadband wireless access channel environments where IEEE 802.16d is to be deployed. It has six channel models that are grouped into three categories according to three typical different outdoor Terrains, in order to give a comprehensive effect of fading channels on the overall performance of the system.
