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The probability of instantaneous accepted packet error outage (IAPEO) is proposed as a performance measure for packet transmission with automatic-repeat-request (ARQ) schemes over wireless channels. It is defined as the probability that the instantaneous accepted packet error probability (IAPEP) exceeds an IAPEP threshold. We obtain a closed-form upper bound expression for IAPEO of a pure ARQ over...
Research and industries are recently more interesting and attracting to the Vehicular Ad hoc Networks (VANETs) development domain. They contribute to safer and more efficient roads by providing timely and accuracy information to drivers and authorities. Thus, the definition of a quality of service routing protocol for VANETs is one of their challenges. In this paper, we propose QoSBeeVanet, a new...
Multicell coordinated beamforming (MCBF) has been recognized as a promising approach to enhancing the system throughput and spectrum efficiency of wireless cellular systems. In contrast to the conventional single-cell beamforming (SBF) design, MCBF jointly optimizes the beamforming vectors of cooperative base stations (BSs) (via a central processing unit (CPU)) in order to mitigate the intercell interference...
Scheduling is an essential mechanism in IEEE 802.16 networks for distributing the available bandwidth among the active connections so that their quality of service requirements can be furnished. Scheduling mechanisms adopted in wired networks, when used in wireless networks lead to inefficient use of the bandwidth since the location dependent and time varying characteristics of the wireless link usually...
The paper studies a protocol and a control architecture aimed at implementing bandwidth and call admission optimization over a DVB Return Channel Satellite Terminal (RCST) under Quality of Service (QoS) contraints. The approach can be applied in all cases where traffic flows, coming from a terrestrial portion of the network, are merged together within a single DVB flow, which is then forwarded over...
Anypath routing, a new routing paradigm, has been proposed to improve the performance of wireless networks by exploiting the spatial diversity and broadcast nature of the wireless medium. In this paper, we study the problem of finding an anypath subject to multiple (K) constraints, which has been proved to be NP-hard. We present a polynomial distributed K-approximation routing algorithm. Our algorithm...
Multiple Input Multiple Output (MIMO) adds a new dimension to be exploited in Cognitive Radio (CR) by simultaneously serving several users. The spatial domain that is added through MIMO is another system resource that has to be optimized, and shared when possible. In the current paper, we present a spatial sharing that is carried out through Zero Forcing beamforming (ZFB). The power consumption in...
One of the most important problems in the field of performance optimization for data networks is the problem of routing to achieve delay minimization. This becomes extremely important in the context of providing Quality of Service while satisfying demand. The problem is classical and was considered three decades ago by a number of authors primarily Gallagher, Bertsekas and Garcia-Luna-Aceves. The...
In this paper, we propose centralized and distributed power allocation algorithms for a multi-user, multi relay cellular network using decode-and-forward (DF) cooperation strategy taking channel uncertainty into account. The objective is to minimize the total uplink power of the network taking each user's target data rate as the quality of service (QoS) constraint under imperfect channel state information...
In NCS (networked control systems), the control performance depends on not only the control algorithm but also the communication protocol stack. This paper presents a framework for the protocol reconfiguration in NCSs. Task queuing, network transmission policy and communication link control are emphasized as three key protocol functionalities related to the system performance. Based on it, data and...
Network virtualization has been recognized as a promising solution to enable the rapid deployment of customized services by building multiple Virtual Networks (VNs) on a shared substrate network. Whereas various VN embedding schemes have been proposed to allocate the substrate resources to each VN requests, little work has been done to provide backup mechanisms in case of substrate network failures...
In this paper, wireless systems operating under queueing constraints in the form of limitations on the buffer violation probabilities are considered. The throughput of wireless systems operating under such constraints is captured by the effective capacity formulation. It is assumed that finite blocklength codes are employed for transmission. Under this assumption, a recent result on the channel coding...
Radio Resource Management (RRM) techniques used in the Worldwide Interoperability for Microwave Access (WiMAX) can provide for many of the services and features promised by 4G wireless networks, such as supporting multimedia services with high data rates, and wide coverage area, as well as all-IP with security and Quality of Service (QoS) support. The IEEE 802.16 standard, associated with the WiMAX,...
This study provides a general framework for distributed multi-user power control problems in cognitive radio (CR) networks over fading channels. Using a non-cooperative game with coupled constraints in CR and primary channel outages, the fundamental performance traits of power control for multiple CR users are analyzed in the present of multiple primary users (PUs) in fading environments for the first...
To provide live streaming service to mobile users, traditionally each user pulls content from a server over his cellular network. In order to overcome the scalability problem of last-hop bandwidth bottleneck, mobile peer-to-peer (P2P) streaming can be used where mobile devices relay their stream received in a multi-hop manner by means of a secondary channel (such as Wi-Fi or bluetooth). We investigate...
Service composition is a useful technology to achieve dynamic requests. But in cloud, the cloud provider should guarantee the QoS of the user request as well. Previous work investigated how to select proper available replicas (the similar functional services located on different physical nodes) to effectively achieve the composite services. However, as the requirements for some service grow, even...
Enhanced Multimedia Broadcast/Multicast Service (eMBMS) is a new function defined in 3GPP specification to support PTMP (point to multiple points) transmission in LTE networks. In order to improve reliability, two mechanisms are implemented in single-cell eMBMS: (1) Raptor is implemented at the eBMSC (Enhanced Broadcast/Multicast Service Center) to provide packet-level protection; (2) HARQ is used...
In wireless networks using hybrid MAC, nodes can reserve time periods inside scheduling cycles, and the time which is not reserved can be used by all the nodes through contention-based access. The hybrid MAC is attractive because it can provide satisfactory QoS by resource reservation and also achieve high channel utilization by multiplexing gain in the contention periods. However, we are still lacking...
This paper investigates the performance of wireless systems that employ finite-blocklength channel codes for transmission and operate under queueing constraints in the form of limitations on buffer overflow probabilities. A block fading model, in which fading stays constant in each coherence block and change independently between blocks, is considered. It is assumed that channel coding is performed...
We consider an underlay cognitive radio network, in which the cognitive users (also referred to as secondary users (SUs)) are allowed to access the licensed spectrum simultaneously with the primary users (PUs). Specifically we solve a beamforming and power allocation problem in the downlink with mixed quality-of-service (QoS) requirements where a set of SUs are required to achieve a specific signal-to-interference...
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