Current Search: Wang, Xin (x)
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Title
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QUIC-TCP: validation of QUIC-TCP through network simulations.
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Creator
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Boughen, Brian, Wang, Xin, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
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Abstract/Description
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The scalability of QUIC-TCP was examined by expanding previous developmental 11-node, 4-flow topology to over 30 nodes with 11 flows to validate QUIC-TCP for larger networks. The topology was simulated using ns-2 network simulator with the same ns-2 module of FAST-TCP modified to produce QUIC-TCP agent that the original development used. A symmetrical topology and a random topology were examined. Fairness, aggregate throughput and the object of the utility function were used as validation...
Show moreThe scalability of QUIC-TCP was examined by expanding previous developmental 11-node, 4-flow topology to over 30 nodes with 11 flows to validate QUIC-TCP for larger networks. The topology was simulated using ns-2 network simulator with the same ns-2 module of FAST-TCP modified to produce QUIC-TCP agent that the original development used. A symmetrical topology and a random topology were examined. Fairness, aggregate throughput and the object of the utility function were used as validation criteria. It was shown through simulation that QUICTCP optimized the utility function and demonstrated a good balance between aggregate throughput and fairness; therefore QUIC-TCP is indeed scalable to larger networks.
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Date Issued
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2013
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PURL
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http://purl.flvc.org/fau/fd/FA0004007
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Subject Headings
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Ad hoc networks (computer networks), Embedded computer systems -- Programming, QUIC TCP (Computer network protocol), Wireless communication systems
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Format
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Document (PDF)
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Title
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Optimal chunk-based resource allocation for OFDMA systems with multiple BER requirements.
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Creator
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He, Tianzhou, Wang, Xin, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
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Abstract/Description
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In wireless orthogonal frequency division multiple-access (OFDMA) standards, subcarriers are grouped into chunks and a chunk of subcarriers is made as the minimum allocation unit for subcarrier allocation. We investigate the chunk-based resource allocation for OFDMA downlink, where data streams contain packets with diverse bit-errorrate (BER) requirements. Supposing that adaptive transmissions are based on a number of discrete modulation and coding modes, we derive the optimal resource...
Show moreIn wireless orthogonal frequency division multiple-access (OFDMA) standards, subcarriers are grouped into chunks and a chunk of subcarriers is made as the minimum allocation unit for subcarrier allocation. We investigate the chunk-based resource allocation for OFDMA downlink, where data streams contain packets with diverse bit-errorrate (BER) requirements. Supposing that adaptive transmissions are based on a number of discrete modulation and coding modes, we derive the optimal resource allocation scheme that maximizes the weighted sum of average user rates under the multiple BER and total power constraints. With proper formulation, the relevant optimization problem is cast as an integer linear program (ILP). We can rigorously prove that the zero duality gap holds for the formulated ILP and its dual problem. Furthermore, it is shown that the optimal strategy for this problem can be obtained through Lagrange dual-based gradient iterations with fast convergence and low computational complexity per iteration. Relying on the stochastic optimization tools, we further develop a novel on-line algorithm capable of dynamically learning the underlying channel distribution and asymptotically approaching the optimal strategy without knowledge of intended wireless channels a priori. In addition, we extend the proposed approach to maximizing the a-fair utility functions of average user rates, and show that such a utility maximization can nicely balance the trade-off between the total throughput and fairness among users.
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Date Issued
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2014
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PURL
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http://purl.flvc.org/fau/fd/FA00004291, http://purl.flvc.org/fau/fd/FA00004291
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Subject Headings
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Adaptive signal processing, Mathematical optimization, Orthogonal frequency division multiplexing, Wireless communication systems
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Format
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Document (PDF)
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Title
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Studies on Stochastic Multi-user Scheduling in Wireless Communication.
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Creator
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Wang, Di, Morgera, Salvatore D., Wang, Xin, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
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Abstract/Description
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We developed a cross layer design which combines retransmission diversity and multi-user diversity for wireless communication. To this end, a joint design of adaptive modulation and coding with retransmission-based automatic repeat request protocol is outlined. This design is applied to devise multi-user scheduling schemes, which can optimally capture the available multi-user and retransmission diversities. In addition, the proposed on-line scheduling algorithms can operate even when the...
Show moreWe developed a cross layer design which combines retransmission diversity and multi-user diversity for wireless communication. To this end, a joint design of adaptive modulation and coding with retransmission-based automatic repeat request protocol is outlined. This design is applied to devise multi-user scheduling schemes, which can optimally capture the available multi-user and retransmission diversities. In addition, the proposed on-line scheduling algorithms can operate even when the underl ying fading channel distribution is unknown, while asymptotically converging to the offline benchmark with guarantees on prescribed fairness and rate requirements. Numerical results are provided to verify the merits of our novel schemes for multi-user transmissions over Nakagami block fading channels.
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Date Issued
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2008
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PURL
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http://purl.flvc.org/fau/fd/FA00012568
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Subject Headings
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Stochastic processes--Data processing, Wireless communication systems, Computer network protocols, Code division multiple access, Modulation (Electronics), Signal processing--Digital techniques
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Format
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Document (PDF)
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Title
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Integrating Multi-user Scheduling with Retransmission Diversity over Wireless Links.
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Creator
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Li, Irena, Zhuang, Hanqi, Wang, Xin, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
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Abstract/Description
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Research presented in this thesis develops a mainly theoretical basis and computer models for enhancing the throughput of multi-user wireless communication networks. The cross-layer combination of an adaptive modulation and coding (AMC) scheme at the physical layer and the use of automatic repeat request (ARQ) retransmi ssions at the data link layer is integrated into a scheduling framework for multi-user networks. Scheduling algorithms incorporating retransmission diversity are derived for...
Show moreResearch presented in this thesis develops a mainly theoretical basis and computer models for enhancing the throughput of multi-user wireless communication networks. The cross-layer combination of an adaptive modulation and coding (AMC) scheme at the physical layer and the use of automatic repeat request (ARQ) retransmi ssions at the data link layer is integrated into a scheduling framework for multi-user networks. Scheduling algorithms incorporating retransmission diversity are derived for three cases of typical network traffic: best-effort, non-realtime, and realtime. For each case, numeric computer si mulations of wireless communications over Nakagami-m block fading channels are developed to examine the effectiveness of the formulated schemes.
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Date Issued
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2008
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PURL
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http://purl.flvc.org/fau/fd/FA00012533
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Subject Headings
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Wireless communication networks, Code division multiple access, Modulation (Electronics), Signal processing (Digital techniques)
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Format
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Document (PDF)