Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Cost/Performance Trade-offs of "Two-Layers" Ad Hoc Multihop Cellular Access Systems
KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
2004 (English)In: Proceedings of the fourth Scandinavian Workshop on Wireless Ad-hoc Networks, 2004Conference paper, Published paper (Refereed)
Abstract [en]

Ad Hoc multihop cellular access is considered tobe a strong candidate for the next generation of public phonesystems. In this paper, we present a novel approach for solving the dimensioning problem of an ad hoc system capable of two hopstransmissions. In this respect, is presented and analyzed a method for comparing the expenditure levels, for deploying andrunning a cellular network, implemented through a multihoppingsystem or through a standard cellular solution selected as reference. In particular, we describe the conditions in which the proposed multihopping solution is feasible, and quantify the performance/cost trade-offs that are achievable. Numerical results show that the spectral efficiency of currently deployed single hop systems can almost be doubled, if the user terminals are capable of multihopping and the cell planning is performed so that a critical mass of user per cell can be guaranteed.

Place, publisher, year, edition, pages
2004.
National Category
Telecommunications
Research subject
SRA - ICT
Identifiers
URN: urn:nbn:se:kth:diva-7632OAI: oai:DiVA.org:kth-7632DiVA: diva2:12718
Conference
the fourth Scandinavian Workshop on Wireless Ad-hoc Networks
Note

QC 20100715

Available from: 2007-11-13 Created: 2007-11-13 Last updated: 2014-07-17Bibliographically approved
In thesis
1. Self-organization, cooperation and control distribution in wide and local area networks
Open this publication in new window or tab >>Self-organization, cooperation and control distribution in wide and local area networks
2007 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

To support the future requirements on wireless systems in an affordable manner it is commonly believed that multiple radio access technologies have to be combined. These technologies can be deployed by a single operator or, even, be managed by different competing operators. In order to cope with the increased complexity of such a multifaced wireless environment it has been argued that a transfer of Radio Resource Management (RRM) functionalities towards the network edges (access ports and, ultimately, user terminals) may be beneficial. In addition to detecting varying system conditions in a faster manner this would also allow a more responsive service adaptation. In this thesis we evaluate a set of self-organizing regimes, all with the purpose of supporting the distribution of control at the edge node.

Particular emphasis is put on the design of a mechanism for dynamically establishing cooperation between different network entities whether these are access ports or user terminals.

Terminal cooperation by means of multihopping is considered in the context of service provision in cellular access systems. Previously the opportunity cost associated with sharing own bandwidth, and energy loss have been seen as a major obstacle for relaying other users’ traffic. To mitigate the effects of this selfish behavior the concept of resource delegation is introduced and evaluated in combination with a rewarding scheme designed for compensating the energy losses induced by forwarding. The results show that our proposed schemes not only are capable of fostering significant cooperation among users, but also to create a simultaneous improvement in user utility, data rates as well as in operator revenues.

Opening up networks of user-deployed Access Points (APs) for service provision is considered a means to radically lower the cost of future wireless services. However, since these networks are deployed in an uncoordinated manner, only discontinuous coverage will be provided. The question of how dense these networks need to be, to deliver acceptable user perception, is investigated in this thesis for a set of archetypical services. The results show that already at moderate AP densities the investigated services can be provided with sufficient quality. Epidemic exchange of popular content and inter-AP cooperation are also shown to further decrease the required infrastructure density and improve the APs’ utilization respectively.

As last contribution, “Word-of-Mouth”, a distributed reputation-based scheme, is investigated in the context of access selection in multi-operator environments. By exchanging information concerning the Quality of Service (QoS) associated with the different networks, terminal agents can collectively reveal the capabilities of individual networks. For a vertical handover scenario we show that our proposed scheme can reward access providers capable of ensuring some degrees of QoS. By introducing a model for collusion, between low performing APs and terminal agents, we show that our proposed scheme is also robust to the dissemination of false information.

Place, publisher, year, edition, pages
Stockholm: KTH, 2007. x, 98 p.
Series
Trita-ICT-COS, ISSN 1653-6347 ; 0702
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-4533 (URN)
Presentation
2007-11-23, Sal N2, KTH-Electrum 3, Isafjordsgatan 28, Kista, Stockholm, 13:00
Opponent
Supervisors
Note
QC 20101112Available from: 2007-11-13 Created: 2007-11-13 Last updated: 2010-11-12Bibliographically approved
2. Context-based Resource Management and Architectures for Future Wide and Local Area Wireless Networks
Open this publication in new window or tab >>Context-based Resource Management and Architectures for Future Wide and Local Area Wireless Networks
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In the last few years we have been witnessing the beginning of a revolution in the world of wireless communication. The recent launch of advanced smartphones in the mobile market has been welcomed by mobile operators as an opportunity to finally fulfill the promises of 3G and increase the uptake of mobile services. Driven by unprecedented user experience and flat rate pricing, the success of novel mobile platforms for accessing multimedia content and applications has gone far beyond the most optimistic of expectations. Data-hungry services are currently creating significant capacity limitations in many networks, and projections on future content consumption anticipate that with the next generation of mobile devices the stress on cellular infrastructures will increase. Rolling-out additional capacity is not the most profitable of solutions given the current cost structure of mobile infrastructures. Instead, a significant cost reduction can be achieved by revolutionizing the current content provision paradigm. Accordingly, this thesis proposes solutions for making future services and infrastructures more affordable. From an operator perspective, terminal-to-terminal information forwarding has the potential to increase both coverage and capacity, however it introduces opportunity costs and energy losses at the user side. Resource delegation, together with an energy reimbursement scheme, is presented in this thesis to induce user cooperation. The results show that this approach is successful in fostering significant cooperation among users and can create a simultaneous improvement in user utility, data rates and operator revenues. Opening up for public access privately deployed WLANs might radically lower the cost of wireless services. However, since these networks are deployed in an uncoordinated manner, only discontinuous coverage can be provided. To hide the sparsity of the infrastructure to the end-user perception we propose the adoption of opportunistic schemes for content pre-fetching. Results show that already with moderate AP densities a set of archetypical services, including web-browsing, can be provided with sufficient user perceived quality. Epidemic exchange of popular content, and inter-AP cooperation are also shown to further decrease the required AP density. Moreover, to support informed access selection decisions when performing vertical handovers to WLANs, we propose “Word-of-Mouth”, a reputation-based scheme for revealing the QoS of different networks. By epidemically exchanging grades on their experienced service quality, we show that terminal agents can collectively improve their decision making, avoiding selecting networks not meeting the required QoS. Context-based content delivery is presented in this thesis as means to improve the utilization of wireless resources in cellular systems. Since networks are typically dimensioned for peak hour traffic, the BSs are underutilized for significant portions of the day. By adopting context-based architectures, capable of opportunistically utilizing the instantaneous excess of resources for content pre-fetching, we show that a significant amount of additional traffic can be served in already existing networks. The gains introduced by this content provision paradigm over the current “on-demand” solutions are further expressed in terms of lower requirements on BS density, more users in the system and larger files served while reaching the same level of user experience.

Place, publisher, year, edition, pages
Stockholm: KTH, 2010. xi, 156 p.
Series
Trita-ICT-COS, ISSN 1653-6347
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-12216 (URN)
Public defence
2010-04-16, C1, Electrum 1, Kungliga Tekniska Högskolan, Isafjordsgatan 26, Kista, 14:00 (English)
Opponent
Supervisors
Note
QC20100716Available from: 2010-04-08 Created: 2010-03-26 Last updated: 2010-07-16Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Lungaro, Pietro
By organisation
Microelectronics and Information Technology, IMIT
Telecommunications

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 139 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf