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State of the Art Analysis of Wireless Mesh Technologies
, 2006
"... Wireless mesh networks are a recent architecture for multihop wireless networks. Also, standards for realizing mesh networks are being actively developed, especially in the IEEE working groups. In contrast with mobile ad hoc networks, mesh networks consist of static nodes communicating with each oth ..."
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Wireless mesh networks are a recent architecture for multihop wireless networks. Also, standards for realizing mesh networks are being actively developed, especially in the IEEE working groups. In contrast with mobile ad hoc networks, mesh networks consist of static nodes communicating with each other over wireless links. The static nodes are essentially wireless routers. Such networks can be used, for example to provide a cost effective alternative to a wireline Internet access network. As opposed to the nodes in mobile ad hoc networks, the nodes in mesh networks are not energy constrained and node mobility is not a concern in protocol scalability. Instead, the main technical problems relate to achieving high user data rates over multihop wireless paths by using advanced MAC/routing layer solutions. This report presents a state-of-the-art analysis of wireless mesh networks, both from the point of view of standardization and academic research activities. In the standardization, we focus on the recent developments on defining new physical layer and MAC layer standards for mesh network in the IEEE 802.11 and 802.16 working groups. At the IP layer, in addition to routing, mobility management is a key issue, and these are reviewed from the point of view of recent IETF activities in the field. In academic research, the emphasis has been on identifying feasible mechanisms that can be used to mitigate the impact of interference
An efficient delay constrained scheduling scheme for IEEE 802.16 networks
, 2007
"... Abstract In this paper, we propose a simple yet efficient delay-constrained scheduling scheme for IEEE 802.16 networks. The proposed scheduling scheme not only can satisfy delay constraints of different service types by manipulating a simple operation parameter but also can achieve a good fairness p ..."
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Abstract In this paper, we propose a simple yet efficient delay-constrained scheduling scheme for IEEE 802.16 networks. The proposed scheduling scheme not only can satisfy delay constraints of different service types by manipulating a simple operation parameter but also can achieve a good fairness performance. An analytical model is developed to evaluate the performance in terms of interservice time, average queue length, and mean waiting time, and is verified through extensive simulations. Furthermore, an implementation procedure of the proposed scheme is given, which reflects the scheme’s good features of the fast re-configurability and adaptability.
Three Dimension QoS Deviation based Scheduling in Adaptive Wireless Networks
"... AbstractQoS provisioning over wireless fading channel is challenging. We develop a novel scheduler design in cellular packet-switched wireless networks which provides QoS for users in all three aspects of QoS i.e. throughput, delay and packet loss simultaneously. We establish a three-dimensional spa ..."
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AbstractQoS provisioning over wireless fading channel is challenging. We develop a novel scheduler design in cellular packet-switched wireless networks which provides QoS for users in all three aspects of QoS i.e. throughput, delay and packet loss simultaneously. We establish a three-dimensional space with specific basis vectors for QoS and find the efficient point of system performance in that space. Then we develop a generalized measure, the QoS Deviation, which is the Euclidean distance between flow QoS work point and the efficient QoS point in the 3D space. Based on this measure, a scheduling approach, namely BQDF is outlined and will be extended to AQDC scheduler for wireless channels which makes it possible to tune the tradeoff between QoS provisioning and optimizing throughput in an adaptive manner depending on current cell QoS Deviation level (CDL). Finally, we introduce a QoS Deviation-based CAC policy for the proposed system Index Termsthreedimensional quality of service (3D-QoS), QoS Deviation, cell QoS Deviation level (CDL), call admission control (CAC), adaptive modulation and coding (AMC). I.
Energy-aware scheduling with probabilistic deadline constraints in wireless networks
"... a b s t r a c t In a shared-medium wireless network, an effective technique that allows for a tradeoff of message transmission time for energy savings is to transmit messages over multiple smaller hops as opposed to using the long direct source-destination hop. In this context, we address the probl ..."
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a b s t r a c t In a shared-medium wireless network, an effective technique that allows for a tradeoff of message transmission time for energy savings is to transmit messages over multiple smaller hops as opposed to using the long direct source-destination hop. In this context, we address the problem of scheduling messages with probabilistic deadline constraints. Unlike most other works in this area, we consider the practical aspects of the erroneous channel condition and the receiver energy consumption while solving the scheduling problem. Our solution is three fold -first we prove that the problem is NP-hard. We then present an Integer Linear Program (ILP) formulation for the scheduling problem. Finally, we present efficient heuristic scheduling algorithms which minimize the energy consumption while providing the required guarantees. Our simulation studies show that the proposed heuristic algorithms achieve energy savings comparable to that obtained using the linear programming methodology under practical channel conditions.
Wireless Evolution with 4G Technologies
"... Abstract: The better the technology, the more user friendly it becomes. This is what 4G brings to us than 3G. 4G provides us 3 times faster speed than 3G technology.4G is the short name of fourth generation of wireless /mobile communication That will enable things like IP -based voice, data, gammin ..."
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Abstract: The better the technology, the more user friendly it becomes. This is what 4G brings to us than 3G. 4G provides us 3 times faster speed than 3G technology.4G is the short name of fourth generation of wireless /mobile communication That will enable things like IP -based voice, data, gamming services & high quality streamed multimedia on portable devices with cable modem like transmission speed. The expectation for the 4G technology is basically the high quality audio/video streaming over end to end Internet Protocol. Third generation mobile, data rates are 384 Kbps (download) maximum, typically around 200kbps, and 64kbps upload. These are comparable to home broadband connections. Fourth generation mobile communications will have higher data transmission rates than 3G. 4G mobile data transmission rates are planned to be up to 100 Mbps on the move and 1Gbps stationary, this is a phenomenal amount of bandwidth, only comparable to the bandwidth workstations get connected directly to a LAN.
Cross-Layer Optimization for Multimedia Transport over Multicode CDMA Networks
"... Abstract—Most previous work on code division multiple access (CDMA) considers the bit error ratio (BER) at the physical layer and the frame drop ratio (FDR) at the medium access control layer separately. However, a better system performance, e.g., in terms of a lower overall frame loss ratio (FLR), ..."
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Abstract—Most previous work on code division multiple access (CDMA) considers the bit error ratio (BER) at the physical layer and the frame drop ratio (FDR) at the medium access control layer separately. However, a better system performance, e.g., in terms of a lower overall frame loss ratio (FLR), can be achieved if BER and FDR are jointly optimized. In this paper, we propose a cross-layer optimization scheme called traffic-adaptive scheme for multicode CDMA operating over a time division multiple access (TDMA) channel. Based on the traffic condition and buffer status, this scheme employs a Markov Decision Process (MDP) to determine the optimal value of the maximum number of simultaneous data frames that can be transmitted in each time slot of a TDMA frame so as to minimize the overall FLR of the system. To facilitate implementation, we also propose an approximation scheme named the rateadaptive scheme to reduce the computation cost. Simulation and analytical results show that both the traffic-adaptive scheme and rate-adaptive scheme can significantly reduce FLR, increase the system throughput, and optimize the packet access delay of the system. Furthermore, the rate-adaptive scheme can achieve a performance close to the traffic-adaptive scheme when the traffic load in the system is high. Index Terms—Multimedia communication, wireless, multicode code division multiple access. Ç 1
1 End-to-end Scheduling Techniques for Mobile Broadcast and Multicast Services
"... Abstract — Several mobile operators have started “broadcastlike” services based on the classical radio and TV channel delivery model. In order to efficiently support mobile multicast and broadcast services 3GPP has standardized MBMS (Multimedia Broadcast Multicast Services) for UMTS (Universal Mobil ..."
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Abstract — Several mobile operators have started “broadcastlike” services based on the classical radio and TV channel delivery model. In order to efficiently support mobile multicast and broadcast services 3GPP has standardized MBMS (Multimedia Broadcast Multicast Services) for UMTS (Universal Mobile Telecommunication System) and GPRS (General Packet Radio Service) in Release 6. MBMS aims at providing a richer set of multimedia experience to its subscribers and is able to serve many more subscribers than its unicast counterpart. The delivery of multicast/broadcast channels over capacity limited radio links requires intelligent scheduling mechanisms that make best use of the available resources. This paper highlights the need for the design of an end-to-end scheduling framework for MBMS by studying scheduling at both the RAN (Radio Access Network) and CN (Core Network) level. The methodology involves introducing a distribution of the identified scheduling sub-functions among all involved entities and includes feedback strategies as well as proposals for the architectural evolution.
QoS in Wireless Data Networks file:///X:/www-docs/cse574-06/ftp/wireless_qos/index.html QoS in Wireless Data Networks
"... Quality of service (QoS) is an important consideration in networking, but it is also a significant challenge. Providing QoS guarantees becomes even more challenging when you add the complexities of wireless and mobile networks. This paper discusses the challenges and solutions involved in providing ..."
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Quality of service (QoS) is an important consideration in networking, but it is also a significant challenge. Providing QoS guarantees becomes even more challenging when you add the complexities of wireless and mobile networks. This paper discusses the challenges and solutions involved in providing QoS in wireless data networks. Multiple techniques for providing service guarantees are presented, including data link layer QoS schemes, network layer schemes, integrated (multiple layer) approaches, QoS routing, dynamic class
