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1 – 4 of 4Linli Cui, Zhenhai Shao, Tian Zhou and Aiyun Li
The purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and…
Abstract
Purpose
The purpose of this paper is to introduce a resource allocation mechanism for Multimedia Broadcast/Multicast Service (MBMS) in a wireless cellular system and to obtain a rapid and efficient transmission scheme over various types' services. The proposed algorithm is evaluated by simulation results.
Design/methodology/approach
A big problem for wireless communication is the limited time/frequency resources. Therefore, the most important issue is how to utilize these limited resources to transmit various services over a wireless broadband network, especially for MBMS services. In this paper, resource allocation mechanism in a full unicast system is first analyzed with three classical methods, then improved modulation and coding schemes (MCS) methods are proposed in a full multicast system to improve system throughput and spectral efficiency. Based on the foregoing discussions, research on resource allocation mechanism for mixed multicast and unicast traffic is developed in single‐cell and multi‐cell system (MBSFN, MBMS over single frequency network), respectively. Different transmission proportions between multicast and unicast are analyzed and a multiplexing scenario is also considered.
Findings
Resource allocation is a hot topic in wireless communication and there are many investigations on it. However, resource allocation for multicast system, especially for mixed multicast and unicast traffic system, is still a problem worthy of further study. Under same transmission condition in a single cell scenario, system throughput in multicast mode is worse than in unicast mode, which is partly because the number of valid date in multicast resource block (RB) is less than the one in unicast in 3GPP LTE/LTE‐A, on the other hand, because that multicast need to select a relative low MCS to satisfy most MBMS users, even the users with a very poor transmission condition. Fortunately, multicast in MBSFN (MBMS over single frequency network) transfer mode can largely improve system performance.
Originality/value
Improved MCS selection schemes are proposed for full multicast transmission and three transmission scenarios for mixed multicast and unicast traffic are presented to discuss resource allocation mechanism over various types' services. Simulation results show that system performance of multicast system can be greatly enhanced in MBSFN transmission mode, especially with MIMO technology.
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Svetlana Boudko, Wolfgang Leister and Stein Gjessing
Coexistence of various wireless access networks and the ability of mobile terminals to switch between them make an optimal selection of serving networks for multicast groups a…
Abstract
Purpose
Coexistence of various wireless access networks and the ability of mobile terminals to switch between them make an optimal selection of serving networks for multicast groups a challenging problem. Since optimal network selection requires large dimensions of data to be collected from several network locations and sent between several network components, the scalability can easily become a bottleneck in large-scale systems. Therefore, reducing data exchange within heterogeneous wireless networks is important. The paper aims to discuss these issues.
Design/methodology/approach
The authors study the decision-making process and the data that need to be sent between different network components. To analyze the operation of the wireless heterogeneous network, the authors built a mathematical model of the network. The objective is defined as a minimization of multicast streams in the system. To evaluate the heuristic solutions, the authors define the upper and lower bounds to their operation.
Findings
The proposed heuristic solutions substantially reduce the usage of bandwidth in mobile networks and exchange of information between the network components.
Originality/value
The authors proposed the approach that allows network selection in a decentralized manner with only limited information shared among the decision makers. The authors studied how different sets of information available to decision makers influenced the performance of the system. The work also investigates the usage of multiple paths for multicast in heterogeneous mobile environments.
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Peter Curwen and Jason Whalley
The purpose of this paper is to analyse technological and regulatory issues arising from the introduction of TV services on mobile handsets.
Abstract
Purpose
The purpose of this paper is to analyse technological and regulatory issues arising from the introduction of TV services on mobile handsets.
Design/methodology/approach
The paper looks at the various technological solutions to the provision of mobile TV and records the progress to date of trials of these technologies. It also examines the regulatory framework in the EU and certain individual countries and analyses the effects of spectrum shortages.
Findings
The paper finds that the existence of competing, incompatible technologies, the constraints on the availability of suitable spectrum, the issue of what content to broadcast and the difficulties of persuading customers to pay for it are holding back the widespread dissemination of mobile TV, but only on a temporary basis.
Originality/value
This paper is the first detailed attempt to investigate this topic.
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Dirk Kutscher, Jörg Ott and Steffen Bartsch
This paper aims to discuss large‐scale operational aspects for network service maps and to present technical solutions and evaluation results.
Abstract
Purpose
This paper aims to discuss large‐scale operational aspects for network service maps and to present technical solutions and evaluation results.
Design/methodology/approach
The paper reviews related work on service discovery specifically for wireless networks and services in, introduces network service maps and their operation in detail and describes their implementation and addresses two specific usage scenarios, based upon which it evaluates its approach through measurements and simulations.
Findings
The paper finds that, in the presence of today's ever‐increasing WLAN services, better support for service selection and automated service configuration is an urgent need to enable people to access these new services efficiently and thus increase their value and utilisation further. This is clearly reflected in different solutions being developed by service providers, roaming operators and device manufacturers that aim to facilitate WLAN usage.
Originality/value
The ubiquity of WLAN services, ranging from campus networks to commercial hotspots and community WLAN services, requires a new approach for automatically locating and using services. The paper presents a service selection infrastructure that is independent of a user's current network attachment and location in a way that users can obtain information of a specific network (or any other service) without being required to be connected to a particular one. Information about networks and services are distributed in a way that allows for using this information offline, e.g. when still looking for appropriate network access.
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