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  • 1.
    Aggerstam, Thomas
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Lourdudoss, Sebastian
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Radamson, Henry H.
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Sjödin, Mikael
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Lorenzini, P.
    CNRS-CHREA.
    Look, D.C.
    Semiconductor Research Center, Wright State University.
    Investigation of the interface properties of MOVPE grown AlGaN/GaN high electron mobility transistor (HEMT) structures on sapphire2006In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 515, no 2, p. 705-707Article in journal (Refereed)
    Abstract [en]

    We have developed a virtual GaN substrate on sapphire based on a two-step growth method. By optimizing the growth scheme for the virtual substrate we have improved crystal quality and reduced interface roughness. Our Al0.22Ga0.78N/GaN HEMT structure grown on the optimized semi-insulating GaN virtual substrate, exhibits Hall mobilities as high as 1720 and 7350 cm(2)/Vs and sheet carrier concentrations of 8.4 x 1012 and 10.0 x 1012 cm(-2) at 300 K and 20 K, respectively The presence of good AlGaN/GaN interface quality and surface morphology is also substantiated by X-Ray reflectivity and Atomic Force Microscopy measurements. A simplified transport model is used to fit the experimental Hall mobility.

  • 2.
    Aggerstam, Thomas
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Sjödin, Mikael
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    Lourdudoss, Sebastian
    KTH, School of Information and Communication Technology (ICT), Centres, Electrum Laboratory, ELAB.
    AlGaN/GaN high-electron-mobility transistors on sapphire with Fe-doped GaN buffer layer by MOVPE2006In: Physica Status Solidi C - Current Topics in Solid State Physics: Vol 3, No 6 / [ed] Hildebrandt S; Stutzmann M, 2006, Vol. 3, p. 2373-2376Conference paper (Refereed)
    Abstract [en]

    A simple AlGaN/GaN HEMT structure without any interlayer on Fe-doped GaN (GaN:Fe) grown by LP-MOVPE in one single run on sapphire is demonstrated. The surface segregation of Fe in GaN occurring during growth is identified. Hall measurements yield 2DEG (two dimensional electron gas) mobilities of 1700 and 10700 cm2/Vs and sheet carrier concentrations of 5.1×10 12 and 5.7×1012 cm-2 at 300 K and 20 K, respectively. Good pinch-off current-voltage (ID-VD) characteristics is observed from AlGaN/GaN HEMTs. A maximum drain current density of 0.6 A/mm and a peak extrinsic transconductance of 200 mS/mm have been observed. The HEMT structure yields very good device isolation as indicated by an isolation current of ≀1 nA at 20 V.

  • 3.
    Agüero, Ramón
    et al.
    University of Cantabria, Spain.
    Berg, Miguel
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Choque, Johnny
    University of Cantabria, Spain.
    Hultell, Johan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Jennen, Ralf
    RWTH Aachen University, Germany.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Muñoz, Luis
    University of Cantabria, Spain.
    Prytz, Mikael
    Ericsson Research.
    Strandberg, Ove
    Nokia, Finland.
    RRM Challenges for Non-Conventional and Low-Cost Networks in Ambient Networks2005Conference paper (Refereed)
    Abstract [en]

    This paper presents an overview of the Radio Resource Management (RRM) functionalities needed for Non-Conventional and Low-Cost Networks. These types of networks are characterized by increased cooperation between different types of networks and providers and they are believed to play a fundamental role for future wireless network networking. The paper describes three specific concepts, which latter is used to identify new RRM challenges. In addition, it identifies the relation between the RRM challenges and the Ambient Networks architecture and functionalities, in particular the multiradio resource management functionality.

  • 4. Ahlberg, M.
    et al.
    Lindmark, B.
    Simons, J.
    Beckman, Claes
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Downlink propagation measurements in the GSM 900 and 1800 MHz bands1999In: IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010), 1999, Vol. 3, p. 1506-1509 vol.3Conference paper (Refereed)
    Abstract [en]

    The authors investigate radio propagation in the GSM 900 and 1800 MHz bands in a typical Swedish suburban environment to determine whether or not it is practically feasible to co-site GSM 900 with GSM 1800 systems. They show that propagation in the GSM 1800 band is considerable higher (about 12 dB) than in the old GSM 900. In many cases this difference can be reduced by using dual band sector antennas with 3 dB higher gain at 1800 MHz. However, they also show that in small cells (radius <1000 m) this difference is of little concern and therefore it is possible to co-locate GSM 1800 sites within existing 900 MHz sites as a cost-effective way to increase the system capacity.

  • 5.
    Ahmad, Ashfaq
    et al.
    Univ Engn & Technol, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Arshad, Farzana
    Univ Engn & Technol, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Naqvi, Syeda I.
    Univ Engn & Technol, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. Univ Engn & Technol, ACTSENA Res Grp, Taxila 47050, Pakistan.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. Univ Turku, Dept Informat Technol, TUCS, FIN-20520 Turku, Finland..
    Design, Fabrication, and Measurements of Extended L-Shaped Multiband Antenna for Wireless Applications2018In: Applied Computational Electromagnetics Society Journal, ISSN 1054-4887, Vol. 33, no 4, p. 388-393Article in journal (Refereed)
    Abstract [en]

    This article expounds a multi-band compact shaped antenna, which is based on CPW ground plane. FR-4 with a thickness of 1.6 mm is used as a substrate for the proposed antenna. The proposed antenna is capable of operating at 1.56 GHz for (Global Positioning System), 2.45 GHz (Wireless Local Area Network) and 4.49 GHz (Aeronautical Mobile Telemetry (AMT) fixed services). The efficiency at 1.56, 2.45, and 4.49 GHz is 79.7, 76.9 and 76.7%, respectively. The VSWR of the presented antenna is less than 1.5 at all the desired resonance modes, which confirms its good impedance matching. The performance of the proposed antenna is evaluated in terms of VSWR, return loss, radiation pattern and efficiency. CST (R) MWS (R) software is used for simulations. In order to validate the simulation results, a prototype of the designed antenna is fabricated and a good agreement is found between the simulated and measured results.

  • 6.
    Ahmad, Waqar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Weerasekera, Roshan
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Weldezion, Awet Yemane
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Power Integrity Optimization of 3D Chips Stacked Through TSVs2009In: ELECTRICAL PERFORMANCE OF ELECTRONIC PACKAGING AND SYSTEMS, NEW YORK: IEEE , 2009, p. 105-108Conference paper (Refereed)
    Abstract [en]

    On-chip power distribution network model for simultaneous switching of 3D ICs stacked through TSVs to choose TSV pattern, maximum number of chips in a stack and location of the decoupling capacitor for early design trade-offs.

  • 7.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Chatzimichail, Konstantinos
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Techno-economics of Green Mobile Networks Considering Backhauling2014In: European Wireless 2014; 20th European Wireless Conference; Proceedings of, Barcelona: VDE Verlag GmbH, 2014, p. 1-6Conference paper (Refereed)
    Abstract [en]

    In this paper we consider a comparative analysis of different deployment solutions in terms of total cost of ownership (TCO) and impact of energy efficiency as a cost parameter, i.e. mobile operator's electric bill. Different deployment options for the wireless segment of the network are considered: macro only versus heterogeneous networks with femto cells to support indoor traffic demand. In addition to the wireless segment different technologies for the backhauling segment are also considered: microwave versus fiber (10G-PON). Considering different user traffic intensities in an urban area and different environments such as business and residential areas, the impact of energy consumption on the TCO has been analyzed. The scope of the paper is extended to compare different backhaul technologies considering the annual increase in the traffic demand up to year 2020. The obtained results indicate that the impact of electric bill becomes more significant over the TCO especially after year 2018. Moreover, the heterogeneous deployment strategy utilizing indoor femto-cells achieves significant savings in terms of electric bill and TCO compared to the macro only solution. However, the saving ratio varies according to the adopted backhauling technology.

  • 8.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Interplay Between Cost,Capacity and Power Consumption in Heterogeneous Mobile Networks2014In: 2014 21st International Conference on Telecommunications, ICT 2014, Lisbon: IEEE Press, 2014, , p. 5p. 98-102Conference paper (Refereed)
    Abstract [en]

    Mobile operators nowadays tend to deploy dense heterogeneous layers of 3G and 4G networks in outdoor and indoor environments by adding more macrocells and small cells (e.g. microcells, picocells and femtocells) in response to the increasing demand for coverage and capacity. Another main driver and enabler behind this tendency is the phenomenon that around 80% of power consumption in mobile communication networks stems from the radio base stations. This situation makes mobile operators opt for the use of lowpower radio base stations to provide better coverage, capacity and an environmentally-friendly operation. In this paper the interplay between the deployment costs, targeted QoS and power consumptions have been studied considering two deployment options for the provisioning of the required mobile broadband coverage and capacity; namely the heterogeneous network (HetNet) option versus the homogenous macrocell deployment option. The main findings indicate that, the perceived saving in the total cost of ownership (TCO) resulting from offloading percentage of network traffic to indoor smallcell, in the case of HetNet, is bounded by the mobile subscriber density per area, their usage patterns, the adopted backhaul solution and the used spectrum resources. In general, a quite paying cost and power saving can be achieved by the heterogonous deployment solution for scenarios with high demand levels especially when there is a need to use the spectrum resources more efficiently.

  • 9.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Study on the effects of backhual solutions on indoor mobile deployment "macrocell vs. femtocell"2013In: 2013 IEEE 24th International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC), IEEE conference proceedings, 2013, p. 2444-2448Conference paper (Refereed)
    Abstract [en]

    The deployment of low cost and low power base stations has been recognized in recent years as a promising cost-efficient solution and energy-efficient strategy. In this paper the femtocell and macrocell deployment options have been compared in the context of indoor mobile broadband deployment, with focus on the effect of different backhauling solutions in power consumption and the total deployment cost. This study has been based on the deployment of mobile broadband services within an area of one square kilometers in a new densely populated business district where the different user demands, spectrum bandwidths, backhaul technologies and radio access technologies are taken into account. Moreover, various deployment scenarios reflecting the business perspectives of mobile operators have been looked into as well. The main findings reached indicate that backhaul solutions contribute differently to cost and power consumption depending on the employed deployment strategy. However, contributions to the total power consumption and to the CapEx and OpEx elements of the total deployment cost elements turned to be more significant in the case of femtocell deployment scenarios than in the case of macrocell ones. It is worthy of notice that the femtocell deployment is more cost-efficient, especially in high demand situation when new macro sites are needed to be deployed.

  • 10.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Evaluation of Spectrum Access Options for Indoor Mobile Network Deployment2013In: 2013 IEEE 24th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC Workshops), IEEE , 2013, p. 138-142Conference paper (Refereed)
    Abstract [en]

    The investments in indoor mobile networks are highly related to the spectrum availability and its associated authorization options. The aim of this paper is to discuss the differences in the spectrum demand taking into consideration both wide and local area network deployment requirements and the kind of actor that provides the indoor wireless access. The analysis covers different authorizations options namely licensed, unlicensed, licensed shared access (LSA) and secondary access. A quantitative approach is used to analyze the differences between macrocell and femtocell deployments focusing on deployment cost and spectrum demand. This is complemented by a qualitative study to explore and discuss the strategic business decisions of different actors in view of the available spectrum bands and spectrum authorization options. The main conclusions from this study are; spectrum has more value in macrocell deployment scenarios than in femtocell ones. More spectrum in macrocell deployment scenarios means that operators can deploy less number of new sites and exploit previous infrastructure investments. Femtocell networks are often coverage limited which allows for frequency re-use. As a consequence, the value of spectrum is not the same for mobile network operators (MNOs) and for local network operator (LNOs). MNOs are traditionally confined to macrocell deployment strategies which entail the exclusive usage of licensed bands. While, the use of licensed spectrum by LNOs may incur more cost than the cost of infrastructure deployment. This explains why the use of unlicensed bands is lucrative and viable for LNOs. Furthermore, the LSA scheme may or could soon become an enabler for LNO's business due to the prevailing technical, regulation and policies developments.

  • 11.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Investment strategies for different actors in indoor mobile market: "in view of the emerging spectrum authorization schemes"2013In: 24th European Regional Conference of the International Telecommunication Society, Florence, Italy, 20-23 October 2013, 2013Conference paper (Refereed)
    Abstract [en]

    The regulatory landscape is changing towards more flexible spectrum management schemes. Such schemes are expected to make additional spectrum resources available and lower the spectrum access barriers. Emerging spectrum authorization schemes such as secondary access (TV White Space) and Licensed Shared Access (LSA) are expected to open doors for new actors rather than traditional MNOs to access licensed spectrum resources at reasonable costs. These schemes will allow actors such as Facility Owners (FO), Mobile Virtual Network Operators (MVNO) and Internet Service Providers (ISPs) to invest in indoor mobile network infrastructure. These actors can act as Local Network Operators (LNO) and build their business models around provisioning of mobile services in locations where there seems to be a hole or lack of service coverage in a particular area within the mobile network operators (MNOs) service footprint. This paper highlights the differences between indoor deployment and outdoor deployment in the light of the available spectrum bands to be used and the possible business models for MNOs and LNOs. In short, the possible investment strategies for provisioning indoor mobile services vary between MNOs and LNOs cases due to economic and regulatory aspects surrounding them. The main finding in this study indicates that the willingness of MNOs to invest in dedicated indoor solutions is driven by the balance between the potential revenues and the deployment cost. Moreover MNOs have more spectrum and investment options compared to LNOs who must bond their investment strategies to the available spectrum resources (i.e. the regulations of spectrum access).

  • 12.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    The Incentives and Challenges of Delivering Linear Broadcasting Services over Cellular Network in Developing Countries: Sudan as Case study2014In: The 25th European Regional Conference of the International Telecommunications Society,Brussels, Belgium, 22nd - 25th June 2014, Brussels: nternational Telecommunications Society , 2014Conference paper (Other academic)
    Abstract [en]

    The Broadcasting sector has been evolved in terms of service production, transmission platform and reception devices in the last few decades. In contrast to cable and satellite platform, which are suitable for fixed reception only, the terrestrial digital platform can support portable, mobile and fixed reception scenarios. In general, there are two options of mobile multimedia service; one is based on a mobile communication network with IP cast known as MBMS (Multimedia Broadcast Multicast Services), while the other is based on broadcast technology. In the context of convergence, the players in the mobile sector argues that unlike traditional mobile  network systems, where the use was restricted to a given application, emerging  mobile networks will be able to carry a variety of services and accordingly separate broadcasting networks will no longer be required. In line with argument, it is not economically viable to roll out dedicated wireless broadband networks by the broadcasters to meet the increasing demand for interactive broadcasting services. That is why the broadcasters may look for innovative mechanism to deliver the broadcast services over mobile broadband network owned by the telecommunication operators.

    The focus on this paper is to investigate the incentives and challenges for such trend in developing countries; taking Sudan as case study. The main conclusion in this paper indicate that a potential economic incentive for delivering the broadcasting service over cellular network in Sudan subject to the deployment of high efficient mobile network. Moreover, the mobile operators may consider support such approach considering the increase demand for additional frequency resource.  However, the key challenges remain in how to develop a suitable regulations landscape to assure fair and competitive business practices on hand while guaranteeing the continuation of the public broadcasting service. In this regard, a new regulation framework needs to be developed to separate the three key functions in digital terrestrial broadcasting value chain (namely the content production and distribution). Further on, the necessary interconnection regulations need to put on place in order to pave the way for rollout of common platform that are necessary for interactive and nonlinear services. 

  • 13.
    Ahmed, Ashraf Awadelkarim Widaa
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Toward capacity-efficient, cost-efficient and power-efficient deployment strategy for indoor mobile broadband2013In: 24th European Regional ITS Conference, Florence 2013, 2013Conference paper (Refereed)
    Abstract [en]

    Mobile operators nowadays tend to deploy dense heterogeneous layers of 3G and 4G networks in outdoor and indoor environments by adding more macrocells and smallcells (e.g. microcells, picocells and femtocells) in response to the increasing subscriber demand for coverage and capacity. The main driver and enabler behind this tendency is the phenomenon that around 80% of power consumption in mobile communication networks stems from the radio base stations. This situation makes mobile operators opt for the use low-power radio base stations to provide better coverage, capacity and a more environment-friendly operation. The use of low-power radio base stations leads to reduction of energy consumption in mobile communication networks power. The aim of this study is to conduct a comparative study between homogenous macrocell deployment and indoor smallcell deployments as alternative solutions for provision of the required indoor coverage and capacity. Moreover, the study highlights the importance of backhaul solutions being critical components in the smallcell network deployment. Furthermore, the scope of the study is extended to cover the investigation of the value of the heterogeneous (i.e. hybrid marcocell-femtocell) deployment scenario as a cost and power-efficient solution versus the homogenous marcocell deployment scenario in view of the variations in the mobile network traffic during the day. The main findings indicate that the CapEx and OpEx of the backhaul solution represent the major part of the total deployment cost in the indoor smallcell deployment scenario (i.e. femtocell case) compared to those of the macrocell deployment scenario. Nonetheless, the perceived saving in the total cost of ownership (TCO) resulting from the use of indoor smallcell (i.e. femtocell) remains a satisfactory and convenient motivation considering the traffic variation across the day, traffic distribution between indoor and outdoor locations and the keenness to use the spectrum resources more efficiently.

  • 14.
    Ahsin, Tafzeel Ur Rehman
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Ben Slimane, Slimane
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Energy Efficiency using Cooperative Relaying2011In: 2011 IEEE 22nd International Symposium On Personal Indoor And Mobile Radio Communications (PIMRC), New York: IEEE , 2011, p. 1698-1702Conference paper (Refereed)
    Abstract [en]

    The rising demand for the high data rates in the future cellular systems, is directly linked with the power consumption at the transmitting nodes. Due to the various economical and environmental factors, it is becoming difficult to maintain the current rate of power consumption per unit of data, for the upcoming generations of the cellular systems. This has shifted the focus of many researchers towards the energy efficiency aspect of the cellular systems and power consumption has become an important design parameter in the recent works. In this article, we propose the use of cooperative communications using low cost fixed relays, in order to reduce the energy consumption at the transmitting nodes for a given quality of service requirement. It has been investigated that, how different factors, such as cell radius, relay position, number of relays and target data rate effects the area energy consumption for the different relaying schemes. It has been shown that, the cooperative relaying schemes along with adaptive resource allocation provides minimum energy consumption along with the better coverage as compared to the non adaptive cooperative relaying schemes.

  • 15.
    Ahsin, Tafzeel Ur Rehman
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Slimane, Ben
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Energy efficient resource allocation and deployment strategies for wireless networks2012In: 2012 5th International Conference on New Technologies, Mobility and Security - Proceedings of NTMS 2012 Conference and Workshops, IEEE , 2012, p. 6208715-Conference paper (Refereed)
    Abstract [en]

    Future wireless systems are being designed for extremely high data rates and are directly contributing to the global energy consumption. This trend is undesirable not only due to the environmental concerns, but to cost as well since energy costs are becoming a significant part of the operating expenditures for the telecom operators. Recently, energy efficient wireless systems have become a new research paradigm. Cooperative communication has shown good potential in improving coverage, providing robust radio links, reducing infrastructure cost, and has the possibility to reduce the total system energy consumption. This paper looks at possible deployment strategies for wireless networks that can reduce the energy consumption. We look at the tradeoff between the number of relay nodes and the number of base stations and their implications on the total energy consumption of wireless networks. The obtained results show that adaptive resource allocation between the base station and the relay node is an efficient way of reducing the energy consumption of the system. Furthermore, this reduction in energy consumption increases with increasing the system target spectral efficiency.

  • 16.
    Aidi, Laili
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Huang, Jin
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Selvakumar, Ekambar
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Tollmar, Konrad
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Blennerud, Greger
    Ericsson.
    How can Mobile Music Streaming Service Take off in India, China and Indonesia?: Analysis of Drivers and Obstacles2012In: , 2012Conference paper (Refereed)
  • 17.
    Aidi, Laili
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Tollmar, Konrad
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Blennerud, Greger
    Ericsson.
    Competing or Aligning? Assessment for Telecom Operator's strategy to address OTT TV/Video services2012Conference paper (Refereed)
    Abstract [en]

    Up until recently, it was rarely direct competition between telecom operators, cable and satellite Pay-TV providers in digital TV/Video, as their business area were different and value chain was well established. However, technology advance has altered digital TV/Video landscape, made these Communication Service Providers (CSPs) cross other’s area and opened door for new actor (OTT player) to enter the market. This triggers second change in the landscape, as it potentially bypasses CSP’s role in digital media value chain.

    There are generic potential options for telecom operator to address OTT service‘s treat, where the trend shows gradual shifts toward allowing or promoting. This study assesses telecom operator’s reaction strategies to react to this digital TV/Video convergence trend. Our analysis reveals two typical relation patterns in the value network, used by telecom operators based on strategy options above, which are ”point-to-point” and ”point-to-multipoint” relation model. We explore the underlining motivations that based these strategies, as well as analysis of the eco-systems: actors identification, business roles and distributed responsibilities among them, where we use ARA (Actors, Resource, Activities) point of view to model these value networks.

  • 18.
    Akhtar, Faiza
    et al.
    UET, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Naqvi, Syeda Iffat
    UET, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Arshad, Farzana
    UET, ACTSENA Res Grp, Taxila 47050, Pakistan..
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. UET, ACTSENA Res Grp, Taxila 47050, Pakistan.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. Univ Turku, TUCS, FIN-20520 Turku, Finland..
    A Flexible and Compact Semicircular Antenna for Multiple Wireless Communication Applications2018In: Radioengineering, ISSN 1210-2512, E-ISSN 1805-9600, Vol. 27, no 3, p. 671-678Article in journal (Refereed)
    Abstract [en]

    This work presents a compact, quad-band planar antenna intended for assimilation into flexible and conformal devices. The CPW-fed semicircular shaped prototype with rake-shaped slots is designed, realized and characterized experimentally. The frequency bands covered by the proposed radiator are centered at 2.5, 3.7, 5.5 and 8 GHz with measured impedance bandwidths of 16%, 13.5%, 11.8% and 14.63%, respectively. The proposed antenna is thus enabled to support WLAN, ISM, Bluetooth, WiMAX LTE and X-band applications. The antenna exhibits a significant gain. The radiation characteristics of the proposed radiator are measured in concave and convex bent shapes at various radii to analyze its flexibility. Performance of the antenna remains almost unaffected in the bent situation. Measurements demonstrate good coherence with simulations. The compactness and good performance of the design both in bent and unbent conditions proves it to be the better contender for future multiband conformal wireless applications.

  • 19.
    Akhtar, Nadeem
    et al.
    University of Surrey, UK.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Queseth, Olav
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Analysis of Signaling Load and Negotiation Complexity using Network Composition2007Conference paper (Refereed)
    Abstract [en]

    In future mobile communications networks using Ambient Networks (AN) technology, users will be able to connect to a multitude of networks operated by different business entities. The technology enablers are advertising of access and service offers, multi-radio access, network selection and roaming support, negotiation of terms and conditions for attachment to networks. In this paper, we investigate the additional load on users and network resources for establishment and management of multiple network connections and business relations. The administrative load is analyzed using commercial uses cases and scenarios with a number of available networks, service providers and payment and ID providers. The signaling load for multiple attachment and negotiation procedures is estimated by modeling signaling sequences for a WLAN system enabled with AN technology. The signaling load is computed for varying numbers of users and for users with varying "willingness to evaluate and negotiate offers". The results show that the most important parameters are the number of attachment attempts per time unit. In the investigated scenarios, the relative load of business related signaling is 0.1 -1.0 % of the transferred user data. Although a large of number of different networks may be used, the number of business agreements and network connections that need to be handled simultaneously will be quite low.

  • 20.
    Alasali, Mohammad
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Beckman, Claes
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    LTE MIMO Performance Measurements on Board Passenger Trains2013Conference paper (Other academic)
    Abstract [en]

    Providing passenger internet on board trains with continuous connectivity at high speeds and over large rural distances is a challenging issue. A frequently used solution to the problem is to use an on board WiFi network connected to the 3G or 4G networks deployed outside the train. In order to be able to provide the capacity and the data rates that tomorrow's business travelers are expecting it has been suggested to use a combination of MIMO and carrier aggregation in the LTE-Advance standard. In this study, we practically investigate the plausibility of using MIMO functionality in an 900 LTE system when the receive antennas are mounted at a train roof about 4m above ground and the base stations antennas are on average placed 2.3km away from the track in towers with an average height of 45m and, hence, most of the time in line of site. It is found that along our test route MIMO is in practice supported by the radio channel at around 70% of the time when the train is travelling with an average speed of 185km/h and the MIMO antennas are mounted 10.5m apart.

  • 21.
    Alasali, Mohammad
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Beckman, Claes
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    LTE MIMO performance measurements on trains2013In: 2013 7th European Conference on Antennas and Propagation (EuCAP), New York: IEEE , 2013, p. 2327-2330Conference paper (Refereed)
    Abstract [en]

    Providing passenger internet on board trains with continuous connectivity at high speeds and over large rural distances is a challenging issue. A frequently used solution to the problem is to use an on board WiFi network connected to the 3G or 4G networks deployed outside the train. In order to be able to provide the capacity and the data rates that tomorrow's business travelers are expecting it has been suggested to use a combination of MIMO and carrier aggregation in the LTE-Advance standard. In this study, we practically investigate the plausibility of using MIMO functionality in an 900 LTE system when the receive antennas are mounted at a train roof about 4m above ground and the base stations antennas are on average placed 2.3km away from the track in towers with an average height of 45m and, hence, most of the time in line of site. It is found that along our test route MIMO is in practice supported by the radio channel at around 70% of the time when the train is travelling with an average speed of 185km/h and the MIMO antennas are mounted 10.5m apart.

  • 22.
    Alasali, Mohammad
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Beckman, Claes
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab). KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Karlsson, M.
    Providing internet to trains using MIMO in LTE networks2014In: 2014 International Conference on Connected Vehicles and Expo, ICCVE 2014 - Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2014, p. 810-814Conference paper (Refereed)
    Abstract [en]

    Providing broadband passenger internet on board trains with continuous connectivity at high speeds and over large rural distances is a challenging issue. One solution to the problem is to use an onboard WiFi network connected to multiple 3G and 4G networks deployed outside the train and aggregate their combined capacity at the IP protocol level. In order to be able to provide the capacity and the data rates that tomorrow’s travelers are expecting, the future 4G standard (LTE-Advance) uses a combination of high order MIMO and carrier aggregation. In this study we use the Swedish company Icomera’s passenger internet system for our investigation. The system provides aggregation of multiple carrier and handover on an IP level. For about 10 years the system has in Sweden primarily been using multiple 3G communication links. However, here we present analysis and onboard measurements of a 2×2 MIMO channel to fast moving train in a live LTE 900 network. The results indicate that MIMO works surprisingly well and it is discussed that by combining 8×8 MIMO with carrier aggregation in future releases of 4G, it may be possible to bring gigabit internet connections to trains.

  • 23. Ali, Amjad
    et al.
    Jafri, Syeda I.
    Habib, Ayesha
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. University of Engineering and Technology (UET), Pakistan.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronics, Integrated devices and circuits. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    RFID Humidity Sensor Tag for Low-cost Applications2017In: APPLIED COMPUTATIONAL ELECTROMAGNETICS SOCIETY JOURNAL, ISSN 1054-4887, Vol. 32, no 12, p. 1083-1088Article in journal (Refereed)
    Abstract [en]

    This article presents a low-cost, flexible, chipless Radio Frequency Identification (RFID) tag for humidity monitoring applications. The tag exhibits moisture sensing feature within a compact geometrical dimension of 20mm x 17.6mm. The design is loaded with 12 resonators, where each resonator represents 1 bit in the frequency domain. For the designed 12-bit tag, 11 inverted C-shaped resonators are dedicated for encoding 11-bit information in their spectral signature. An integrated meandered-shaped resonator, covered with moisture sensitive Kapton (R) HN film, functions as a 1-bit moisture sensor. It is deployed for monitoring relative humidity (RH) levels, simultaneously. The passive RFID tag is realized on Taconic TLX-0 and has an operational bandwidth of 2.62 GHz. Furthermore, the design is modeled and analyzed for multiple substrates. The performance of the sensor tag for various humidity levels indicates that it is a potential solution for inexpensive sensing applications.

  • 24.
    Alvarez Alvarez, Oscar
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    A COMPARATIVE STUDY OF SMART GRID DEVELOPMENT IN DEVELOPED AND DEVELOPING COUNTRIES2014Conference paper (Refereed)
    Abstract [en]

    During recent years, there has been an increasing interest in the potential opportunities that can be attained with the use of smart devices in order to gather data or automate processes. This type of communications between devices with minimal human intervention is referred to as Machine-to-machine (M2M) communications that can be applied to optimize resources and improve service delivery applications. Smart Grid is one of the M2M communications applications that is attaining more attention during recent years, because of its potential to change the complete energy ecosystem; going from a unidirectional system to a bidirectional one where customers will have an important role in the ecosystem.Depending on the country and its characteristics and situation, Smart Grid development can be very different. This article identifies commonalities and differences in Smart Grid communication development considering the current status in developed and developing countries. The process is done by evaluating the following techno-economic aspects: Technology development, Public initiatives, Regulator policies and Economic situation/Business perspective of the country. The article is concluded by showing that regulator policies regarding the level of liberalization in the energy market are a key element when defining business strategies and different stages of Smart Grid communications development has a critical influence in the definition of business models, as it defines the key activities, partners and value proposition for the business.

  • 25.
    Alvarez Alvarez, Oscar
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Ghanbari, Amirhossein
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Smart Energy: Competitive Landscape and Collaborative Business Models2015In: 2015 18th International Conference on Intelligence in Next Generation Networks, ICIN 2015, IEEE Communications Society, 2015Conference paper (Refereed)
    Abstract [en]

    During the recent years several technologies and services based in Internet of Things (IoT) and Machine-to-Machine communications (M2M) have appeared in many different sectors, like healthcare, transport, logistics, media or utilities. When new technologies (like Smart Grid or Smart Energy) appear two types of challenges can be defined: technical and business challenges, therefore innovation has to be applied in both of them. Too often innovation is focus on the technical evolution and underestimated on the business field, however it is a key aspect for new technologies and services to reach commercial success. Traditional business models in the energy sector will suffer big changes in the next years, as the Smart Grid concept is developed.By the advent of new services and applications, horizontal and vertical partnerships with competitors and other actors will take place. In this context collaboration between actors, partnerships and agreements will be of key importance. This paper investigates the different actors involved in a Smart Energy ecosystem, its possible activities and suitable business models for the different Smart Grid building blocks or milestones.

  • 26.
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Printable Green RFID Antennas for Embedded Sensors2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the recent years, radio-frequency identification (RFID) technology has been widely integrated into modern society applications, ranging from barcode successor to retail supply chain, remote monitoring, detection and healthcare, for instance. In general, an RFID tag or transponder is composed of an antenna and an application-specific integrated circuit chip. In a passive UHF RFID system (which is the focus of presented research), the communication between the transponder tag and the reader is established by modulating the radar cross section (RCS) of the transponder tag. The need for flexible RFID tags has recently been increased enormously; particularly the RFID tags for the UHF band ensure the widest use but in the meantime face considerable challenges of cost, reliability and environmental friendliness.

    The multidimensional focus of the aforementioned research encompasses the production of low-cost and reliable RFID tags. The state-of-the-art fabrication methods and materials for proposed antennas are evaluated in order to surmount the hurdles for realization of flexible green electronics. Moreover, this work addresses the new rising issues interrelated to the field of economic and eco-friendly tags comprising of paper substrate. Paper substrates offer numerous advantages for manufacturing RFID tags, not only is paper extensively available, and inexpensive; it is lightweight, recyclable and can be rolled or folded into 3D configurations.

    The most important aspect of an RFID system's performance is the reading range. In this research several pivotal challenges for item-level tagging, are resolved by evolving novel structures of progressive meander line, quadrate bowtie and rounded corner bowtie antennas in order to maximize the reading distance with a prior selected microchip under the various constraints (such as limited antenna size, specific antenna impedance, radiation pattern requirements). This approach is rigorously evolved for the realization of innovative RFID tag antenna which has incorporated humidity sensor functionality along with calibration mechanism due to distinctiveness of its structural behavior which will be an optimal choice for future ubiquitous wireless sensor network (WSN) modules.

    The RFID market has grown in a two-dimensional trend, one side constitutes standalone RFID systems. On the other side, more ultramodern approach is paving its way, in which RFID needs to be integrated with broad operational array of distinct applications for performing different functions including sensors, navigation, broadcasting, and personal communication, to mention a few. Using different antennas to include all communication bands is a straightforward approach, but at the same time, it leads to increase cost, weight, more surface area for installation, and above all electromagnetic compatibility issues. The indicated predicament is solved by realization of proposed single wideband planar spirals and sinuous antennas which covers several bands from 0.8-3.0GHz. These antennas exhibit exceptional performance throughout the operational range of significance, thus paving the way for developing eco-friendly multi-module RF industrial solutions.

  • 27.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Design and Analysis of Efficient and Compact Antenna for Paper Based UHF RFID Tags2008In: ISAPE 2008: THE 8TH INTERNATIONAL SYMPOSIUM ON ANTENNAS, PROPAGATION AND EM THEORY, PROCEEDINGS, VOLS 1-3 / [ed] Su D; Yan Z, NEW YORK: IEEE , 2008, p. 62-65Conference paper (Refereed)
    Abstract [en]

    Paper substrate is one of the paramount nominees for Radio Frequency Identification (RFID) tags but at the same time it is extremely prone towards environmental changes. In this paper, antennas for UHF RFID tags on paper based substrate are investigated and analyzed for the first time to evaluate the effect of change in dielectric constant on the antenna parameters and performance. On the basis of analysis a concrete meander line antenna is proposed, designed and evaluated which has tremendous immunity towards variation in dielectric constant.

  • 28.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Evolutionary Versatile Printable RFID Antennas For "Green" Electronics2012In: Journal Electromagnetic Waves and Applications, ISSN 0920-5071, E-ISSN 1569-3937, Vol. 26, no 2-3, p. 264-273Article in journal (Refereed)
    Abstract [en]

    The development of low cost directly printable RFID tag antennas is essential for item level tracking. We present evolutionary design approach to achieve robust extremely versatile RFID antennas on paper/flexible substrates which allow a simple integration directly on, e.g., paperboard in a roll-to-roll production line. Fully integrated printed tags for "green" electronics are designed for operability in frequencies 866-868 MHz & 902-928 MHz. We present benchmarking results for various challenges of antennas in terms of ruggedness, reliability and flexing performance.

  • 29.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Performance-Optimized Quadrate Bowtie RFID Antennas For Cost-Effective and Eco-Friendly Industrial Applications2012In: Progress in Electromagnetics Research-PIER, ISSN 1559-8985, Vol. 126, p. 49-64Article in journal (Refereed)
    Abstract [en]

    Fully integrated printed RFID antennas show potential solution for item level labeling applications. In order to accommodate the antenna during the package printing process, it is vastly preferred that antenna structures are printed on paper substrates. However, the electromagnetic properties and thickness of paper substrates are susceptible to change due to various environmental effects. Thus, adequately consistent in performance and material insensitive printed Quadrate Bowtie RFID antennas are proposed. This paper presents an in-depth efficient optimization for high performance tag antenna designs for operability in frequencies 866-868MHz & 902-928MHz. It is demonstrated that the proposed antennas can tolerate a considerable variation in the permittivity on thin paper substrates, and present benchmarking results when n across metal and water containing objects.

  • 30.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Design and Fabrication of Wideband Archimedean Spiral Antenna Based Ultra-Low Cost "Green" Modules for RFID Sensing and Wireless Applications2012In: Progress In Electromagnetics Research-PIER, ISSN 1559-8985, Vol. 130, p. 241-256Article in journal (Refereed)
    Abstract [en]

    A parametric analysis is performed for a wideband Archimedean spiral antenna in recognition of an emerging concept to integrate RFID along with several applications by using a single antenna. The antenna is fabricated using state-of-the-art inkjet printing technology on various commercially available paper substrates to provide the low-cost, flexible RF modules for the next generation of "green" electronics. The effects on electromagnetic characteristics of the planar Archimedean spiral antenna, due to the use of paper are investigated besides other parameters. The proposed antenna is evaluated and optimized for operational range from 0.8-3.0GHz. It exhibits exceptional coverage throughout numerous RFID ISM bands so do for other wireless applications.

  • 31.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Development and Analysis of Flexible UHF RFID Antennas For "Green" Electronics2012In: Progress In Electromagnetics Research-PIER, ISSN 1070-4698, Vol. 130, p. 1-15Article in journal (Refereed)
    Abstract [en]

    In this paper, novel Bowtie antennas which cover complete UHF RFID band (860-960MHz), fabricated on various ultra-low-cost substrates using state-of-the-art printing technologies are investigated as an approach that aims to accommodate the antenna during the package printing process whilst faster production on commercially available paper. The proposed antenna structures are evaluated in reference to circuit and field concepts, to exhibit extreme degree of functional versatility. These antennas are developed to cater the variations which appear in electromagnetic properties and thickness of paper substrate due to various environmental effects. Computed (simulated) and well-agreed measurement results confirm a superior performance of the tag modules while stepping towards next generation of "green" tags.

  • 32.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    "Green" Wideband Log-Spiral Antenna for RFID Sensing and Wireless Applications2012In: Journal of Electromagnetic Waves and Applications, ISSN 0920-5071, Vol. 26, no 14-15, p. 2043-2050Article in journal (Refereed)
    Abstract [en]

    The novel idea of integrating RFID with sensors along with other wireless applications by using single tag antenna is implemented, by fabricating proposed antenna using state-of-the-art inkjet printing technology on commercially available paper substrates. For the first time, a parametric analysis is performed for realization of planar log-spiral antenna on paper for operational range from 0.8-3.0GHz, which also exhibits excellent coverage throughout numerous RFID ISM bands, and for other wireless applications. The ANSYS HFSS tool is used to design and predict the performance of the proposed antenna in terms of radiation pattern and input impedance.

  • 33.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Two-arm Sinuous Antenna for RFID Ubiquitous Sensors and Wireless Applications2012In: Journal Electromagnetic Waves and Applications, ISSN 0920-5071, E-ISSN 1569-3937, Vol. 26, no 17-18, p. 2365-2371Article in journal (Refereed)
    Abstract [en]

    For the first time, two-arm planar sinuous antenna is demonstrated to realize the emerging concept of integrating RFID functionalities along with sensors and other wireless applications for "green" electronics. In-depth, parametric analysis is performed for the proposed antenna which is fabricated on a paper substrate using revolutionary inkjet printing technology to develop a system-level solution for ultra-low-cost mass production of multipurpose wireless tags in an approach that could be easily expanded to other microwave and wireless "cognition" applications. The proposed antenna exhibits excellent performance throughout several RFID ISM bands and for other wireless applications in its operational range from 0.8 to 3.0 GHz.

  • 34.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Feng, Yi
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    RFID antenna humidity sensor co-design for USN applications2013In: IEICE Electronics Express, ISSN 1349-2543, E-ISSN 1349-2543, Vol. 10, no 4, p. 20130003-Article in journal (Refereed)
    Abstract [en]

    We demonstrate for the first time an RFID tag antenna which itself is humidity sensor and also provides calibration functionality. The antenna is comprised of T-matching network and horizontally meandered lines for impedance matching and reliable near-field communication. The novel contour design provides humidity sensing, and calibration functions whilst concurrently acts as a radiating element along with quadrangular capacitive tip-loading with covered middle portion for far-field communication. The inkjet printed prototypes of the antenna provide effective ambient humidity sensing while demonstrating stable RFID communication. The antenna has a compact size of 1.1 x 10.2 cm for 902-928MHz band.

  • 35.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Prokkola, Satu
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Robust Flexible High Performance UHF RFID Tag Antenna2009In: 2009 11TH ELECTRONICS PACKAGING TECHNOLOGY CONFERENCE (EPTC 2009), NEW YORK: IEEE , 2009, p. 235-239Conference paper (Refereed)
    Abstract [en]

    This paper describes a novel Flexo, Screen and Inkjet printed rounded edges bowtie antenna with T-matching stubs on paper, Kapton (HN) and Teonex Q51 substrate. Paper is one of the paramount nominees for Radio Frequency Identification (RFID) tags, for the reason that it is one of the widely and the cheapest available substrates. Kapton (HN) and Teonex Q51 are distinguished for their flexibility and reliability. The antenna exhibits compact size with outstanding read range of 4 meters and complete coverage of UHF RFID band (860-960 MHz). The results show extreme immunity of versatile antenna against harsh environments. These antennas are flexible which give autonomy for their applications.

  • 36.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Design of Novel Paper-based Inkjet Printed Rounded Corner Bowtie Antenna for RFID Applications2010In: Sensors & Transducers Journal, ISSN 2306-8515, E-ISSN 1726-5479, Vol. 115, no 4, p. 160-167Article in journal (Refereed)
    Abstract [en]

    This paper presents a novel inkjet printed rounded corner bowtie antenna with T-matching stubs on paper substrate which is the cheapest and widest available substrate. The antenna exhibits compact size with outstanding read range and complete coverage of UHF RFID band (860-960 MHz). The results show extreme immunity of proposed antenna against paper dielectric constant variation.

  • 37.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Kanth, R. K.
    Liljeberg, P.
    Akram, A.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Printable RFID antenna with embedded sensor and calibration functions2013In: Progress In Electromagnetics Research Symposium Proceedings, Stockholm, Sweden, Aug. 12-15, 2013, Electromagnetics Academy , 2013, p. 567-570Conference paper (Refereed)
    Abstract [en]

    An RFID antenna with integrated humidity sensor and calibration functionality for wireless sensor network is proposed. The antenna is composed of series and shunt stubs for impedance matching and reliability for near-field communication. The innovative ladder contour structure plays the key role for humidity sensing, and sensor calibration. The quadrangular end-tip loading is employed to offer capacitance and stability for far-field communication. The prototypes of the antenna are fabricated and tested: antenna effectively senses the ambient humidity levels while demonstrating stable behavior for RFID communication. The antenna has a compact size of 1 × 10cm for 902-928 MHz RFID band.

  • 38.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems.
    Kanth, Rajeev Kumar
    Turku Centre for Computer Science (TUCS).
    Liljeberg, Pasi
    Turku Centre for Computer Science (TUCS).
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Green wideband RFID tag antenna for supply chain applications2012In: IEICE Electronics Express, ISSN 1349-2543, Vol. 9, no 24, p. 1861-1866Article in journal (Refereed)
    Abstract [en]

    In this paper, we demonstrate an RFID tag antenna manufactured by advanced inkjet printing technology on paper substrate using novel hole-matching technique for reducing the consumption of substrate material and conductive ink while attaining green RFID tags. In-depth electromagnetic analysis is performed methodologically for optimizing the parameters that effectuate the antenna dimensions. The antenna design is optimized for consistent wideband performance and extended read range throughout the complete UHF RFID band (860-960MHz), while exhibiting benchmarking results when n across cardboard cartons filled with metal or water containing objects.

  • 39.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Kumar Kanth, Rajeev
    University of Turku, Finland.
    Liljeberg, Pasi
    University of Turku, Finland.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Performance-optimized Printed Wideband RFID Antenna and Environmental Impact AnalysisIn: ETRI Journal, ISSN 1225-6463, E-ISSN 2233-7326Article in journal (Refereed)
    Abstract [en]

    This paper presents performance optimized RFID tag antenna, developed by using commercially accessible paper substrates and advanced inkjet printing process to guarantee mechanical flexibility and ultra-low production costs. The proposed antenna structure can endure the variations which emerge in electromagnetic properties of paper substrate due to varying environmental effects. Hole-matching technique is implemented to eliminate the matching network for reducing the consumption of conductive ink. The proposed structure is uniquely evaluated by demonstrating, sustainability and environmental impact analysis that validate the potential for ultra-low cost mass production of RFID tags for future generation of organic electronics. The antenna performance is assessed for cardboard cartons exclusively containing metal cans and water bottles. The experimental characterization of the proposed antenna endorses the wider bandwidth to cover UHF RFID ISM band (860-960MHz), which empowers its usage throughout the globe for supply chain applications. The improved design effectuates return loss of better than -15dB over a wide frequency range while exhibiting outstanding readability from 10.1 meters.

  • 40.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Prokkola, Satu
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Low Cost Paper Based Bowtie Tag Antenna for High Performance UHF RFID Applications2009In: NANOTECH CONFERENCE & EXPO 2009, VOL 1, TECHNICAL PROCEEDINGS - NANOTECHNOLOGY 2009: FABRICATION, PARTICLES, CHARACTERIZATION, MEMS, ELECTRONICS AND PHOTONICS / [ed] Laudon M; Romanowicz B, BOCA RATON: CRC PRESS-TAYLOR & FRANCIS GROUP , 2009, p. 538-541Conference paper (Refereed)
    Abstract [en]

    Radio frequency identification (RFID) antenna's versatility in terms of complete coverage of UHF RFID band (860-960 MHz), while keeping the cost factor low, is an important aspect of today's growing demand for security and tracking of multiple objects in a very short time in addition to tag's readability across the globe. This paper presents a novel inkjet printed rounded corner bowtie antenna with T-matching stubs on paper substrate which is the cheapest and widest available substrate. The antenna exhibits compact size with outstanding read range.

  • 41.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Prokkola, Satu
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Inkjet Printed Paper Based Quadrate Bowtie Antennas For UHF RFID Tags2009In: 11TH INTERNATIONAL CONFERENCE ON ADVANCED COMMUNICATION TECHNOLOGY, VOLS I-III, PROCEEDINGS, - UBIQUITOUS ICT CONVERGENCE MAKES LIFE BETTER!, TAEJON: ELECTRONICS TELECOMMUNICATIONS RESEARCH INST , 2009, p. 109-112Conference paper (Refereed)
    Abstract [en]

    Paper substrate is one of the paramount nominees for Radio Frequency Identification (RFID) tags, for the reason that it is one of the widely and the cheapest available substrates. In this paper, for the first time quadrate bowtie antennas with round corners [1] are realized and analyzed on paper substrate for UHF RFID tags. These inkjet printed antennas exhibit high performance which give freedom for their applications. Their area is smaller than the general triangle bowtie antenna and have advantages of smaller area, better return loss in high frequency and higher gain in normal direction of antenna plane compared with general triangular bowtie antenna.d

  • 42.
    Amin, Yasar
    et al.
    University of Engineering and Technology, Taxila, Punjab, Pakistan.
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Electromagnetic Analysis of Radio Frequency Identification Antennas for Green Electronics2013In: Electromagnetics, ISSN 0272-6343, E-ISSN 1532-527X, Vol. 33, no 4, p. 319-331Article in journal (Refereed)
    Abstract [en]

    This article demonstrates in-depth electromagnetic analysis of a radio frequency identification tag antenna manufactured by inkjet printing technology on different paper substrates to achieve ultra-low cost flexible radio frequency identification tags using a novel hole-matching technique for reducing the consumption of substrate material, and conductive ink. Nevertheless, the electromagnetic properties of the paper substrate are vulnerable to various environmental effects. Thus, the proposed antenna design is optimized for consistent wideband performance throughout the complete UHF radio frequency identification band (860960 MHz) while presenting a greater degree of material insensitivity. An advanced antenna design methodological analysis is performed to accomplish an extended read range, while exhibiting benchmarking results when across cardboard cartons filled with metal or water containing objects.

  • 43.
    Amin, Yasar
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Shao, Botao
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Hållstedt, Julius
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Prokkola, Satu
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Zheng, Li-Rong
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Design and Characterization of Efficient Flexible UHF RFID Tag Antennas2009In: 2009 3RD EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION, NEW YORK: IEEE , 2009, p. 2682-2684Conference paper (Refereed)
    Abstract [en]

    In this paper meander line antennas with end tip loading, designed for UHF RFID tags are presented. These novel antennas are screen printed on Kapton HN for European frequency band (866-868 MHz) and for North American frequency band (902-928 MHz). Asahi ink is used for screen printing of 25 mu m thick antenna traces which remains conductive even after several times sharp bending of these tag antennas. The results show that the antennas exhibit high performance regarding smaller area, high realized gain and better return loss in the frequency band of interest. These antennas are extremely flexible which give autonomy for their applications.

  • 44. An, J.
    et al.
    Yang, X.
    Wang, W.
    Li, J.
    Wang, H.
    Yu, Z.
    Gong, C.
    Wang, X.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Information and Communication Technology (ICT), Centres, Zhejiang-KTH Joint Research Center of Photonics, JORCEP.
    Stable and efficient PbS colloidal quantum dot solar cells incorporating low-temperature processed carbon paste counter electrodes2017In: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 158, p. 28-33Article in journal (Refereed)
    Abstract [en]

    Colloidal quantum dot (CQD) solar cells with a ZnO/PbS-TBAI/PbS-EDT/carbon structure were prepared using a solution processing technique. A commercially available carbon paste that was processed at low-temperatures was used as a counter electrode in place of expensive noble metals, such as Au or Ag, which are used in traditional PbS CQD solar cells. These CQD solar cells exhibited remarkable photovoltaic performance with a short circuit density (Jsc) of 25.6 mA/cm2, an open circuit voltage (Voc) of 0.45 V, a fill factor (FF) of 51.8% and a power conversion efficiency (PCE) as high as 5.9%. A reference device with an Au counter electrode had a PCE of 6.0%. The PCE of the carbon-containing CQD solar cell remained stable for 180 days when tested in ambient atmosphere, while the PCE of the Au-containing CQD solar cell lost 48.3% of its original value. Electrochemical impedance spectroscopy (EIS) demonstrated that holes within the PbS CQD were effectively transported to the carbon counter electrode.

  • 45. Anam, Hafsa
    et al.
    Habib, Ayesha
    Jafri, Syeda Irum
    Amin, Yasar
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Directly Printable Frequency Signatured Chipless RFID Tag for IoT Applications2017In: Radioengineering, ISSN 1210-2512, E-ISSN 1805-9600, Vol. 26, no 1, p. 139-146Article in journal (Refereed)
    Abstract [en]

    This paper proposes a low-cost, compact, flexible passive chipless RFID tag that has been designed and analyzed. The tag is a bowtie-shaped resonator based structure with 36 slots; where each patch is loaded with 18 slots. The tag is set in a way that each slot in a patch corresponds to a metal gap in the other patch. Hence there is no mutual interference, and high data capacity of 36 bits is achieved in such compact size. Each slot corresponds to a resonance frequency in the RCS curve, and each resonance corresponds to a bit. The tag has been realized for Taconic TLX-0, PET, and Kapton (R) HN (DuPont (TM)) substrates with copper, aluminum, and silver nanoparticlebased ink (Cabot CCI-300) as conducting materials. The tag exhibits flexibility and well optimized while remaining in a compact size. The proposed tag yields 36 bits in a tag dimension of 24.5. 25.5 mm(2). These 36 bits can tag 2(36) number of objects/items. The ultimate high capacity, compact size, flexible passive chipless RFID tag can be arrayed in various industrial and IoT-based applications.

  • 46.
    Andersson, Daniel
    et al.
    Radarbolaget, Gävle.
    Wallin, Kjell
    Radarbolaget, Gävle.
    Javashvili, Otar
    Högskolan i Gävle, Radio Center Gävle.
    Beckman, Claes
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    M-Sequence UWB Radar for Industrial Applications2010In: Program of GigaHertz Symposium 2010, March 9-10, at Lund University, 2010Conference paper (Other academic)
    Abstract [en]

    Ultra Wideband Radar has the potential of dramatically improving the control and surveillance of industrial processes in confined areas. An example is the application of UWB radar for surveillance of furnaces for heath treatment of steel billets developed by Radarbolaget in Gävle.

    In our installation at AB Sandvik Materials Technology, we have shown that by using a non-destructive UWB Radar technique it is possible to visualize in real-time the ongoing process inside the furnace behind a 0.5 m thick ceramic wall. Since the operating temperature inside the furnace is 1200 °C, there is today no other known method capable of visualizing the process for the operator of the furnace. The system is therefore designed to sustain high temperatures and powerful electromagnetic disturbances while performing measurement with wide dynamics and high stability.

    The design of this radar is based on the idea of transmitting a continuous m-sequence and then detecting the correlated impulse response (see figure below). The wide bandwidth is a requirement for obtaining high spatial accuracy and resolution but puts further requirements on the design of the antennas and the electronics. Our results show that with this technique it is possible to determine the deformation of the steel billets inside the furnace with an accuracy of less than 5 mm. The radar system is also able to detect deformations in the furnace wall

    The m-sequence radar has many advantages over other UWB radar technologies since it e.g. does not require many analogue components. Its performance is a result of the choice of code length, sampling rate and averaging. However, the resolution is still limited by the impulse response of the analogue antenna (ringing).

    In this paper system parameters that affect the overall performance of an m-sequence radar are reviewed and means of enhancing its performance are discussed.

  • 47.
    Andersson, Göran
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Västberg, Anders
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Devlic, Alisa
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Cavdar, Cicek
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Energy efficient heterogeneous network deployment with cell DTX2016In: 2016 IEEE International Conference on Communications (ICC),, IEEE, 2016, p. 1-6Conference paper (Refereed)
    Abstract [en]

    This paper evaluates different means of reducing power consumption of macro base stations (BS) and heterogeneous mobile network deployments (HetNet) considering the time dimension. These approaches are based on the same idea of reducing the load of heavily loaded macro cells and putting them to discontinuous transmission (DTX) mode during the time of inactivity by either (1) macro cell densification or (2) offloading traffic to small cells. Activity factor of a BS is defined as the fraction of time the BS is transmitting over a fixed time period. It is shown that by macro cell layer network densification, the average daily area power consumption can be reduced by up to 73 % with the use of cell DTX. However, reducing the activity factor by macro layer densification is not cost effective, as already demonstrated in previous studies. Alternatively, by adding small cells and enabling their DTX capability, power consumption can be reduced by up to 29 %. Adding small cells is especially effective in terms of energy savings, when users are distributed around hot spots, where additional coverage and capacity is required.

  • 48.
    Andersson, Per
    et al.
    Handelshögskolan, Stockholm School of Economics.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Capabilities for Network Operations and Support of Customers’ Working Processes2007Conference paper (Refereed)
    Abstract [en]

    In this work in progress paper we will discuss company capabilities related to telecom services and how they can be developed or acquired in order to increase the compositeness of the firm. Traditionally, the technical infrastructure and platforms are designed and deployed by the vendors and operators and the role of end-users, private persons or enterprises,  is to accept the offered service, pay and use. This may be a sustainable model when the user requirements are limited to connectivity, communication between persons and internet access, and to delivery of media services where the network acts as a channel. However, we argue that the design and deployment process of telecom services must be changed in order to provide flexible support of customers´ working processes. As a supplier you also have to consider how value is added in the working process of the customer. The full paper will include problem formulation, research questions, theoretical analysis and empirical data from case studies. 

  • 49.
    Andersson, Per
    et al.
    Handelshögskolan, Stockholm School of Economics.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS. KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Value added services and new business roles for support of mobile professional users and project working processes2008Conference paper (Refereed)
    Abstract [en]

    In this paper we will discuss services that support the value creation process and the interaction between companies in the supply chain. The value added services for professional users hence should support both the internal working processes within a company and, maybe even more important, the interaction between different market actors.   We will discuss how communication systems and value added services can be designed in order to support professional users.

    We target business users using services supporting work in mobile environments with a temporary project organization. The discussion and some analysis will be based on findings from construction projects and from public safety services.  These “projects” are usually temporary with different duration, highly mobile and geographically distributed organizations with common work processes that require close interaction between multiple users and partners belonging to different organizations.

    The analysis starts with characterization of user behavior, user environments and project organizations.  Communication and mobility patterns are described and possible services and business roles are proposed.

    Analysis of empirical results in identification of different types of organization of the provider network. The position of actors within this network is important. Using these findings we discuss adaptive or adaptable business models that could be configured in different ways depending on the duration and the position of actors within the network. An important aspect is the ability for companies to change perspective and consider new ways to assess business opportunities and/or to organize the value creation activities. 

  • 50.
    Andersson, Per
    et al.
    Handelshögskolan, Stockholm School of Economics.
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth.
    Mattsson, Lars-Gunnar
    Handelshögskolan, Stockholm School of Economics.
    Global policy networks’ involvement in service innovation. Turning the mobile phone into a wallet by applying NFC technology2011In: The IMP Journal, ISSN 2059-1403, E-ISSN 0809-7259, Vol. 5, no 3, p. 193-211Article in journal (Refereed)
    Abstract [en]

    The mobile phone attracts an increasing number of service applications enabled by technical developments. On-going efforts aim to widen the scope of mobile payments and “turning the mobile phone into a wallet” with the help of Near Field Technology (NFC). A number of industries are involved in this development. To enable large scale commercial application of the new technology for mobile payments, several global industry associations, what we label Global Policy Networks (GPNs), are involved in standard setting, certification, visions and promotion of business applications, etc. The purpose of the paper is to analyze the role of GPNs in establishing global policies to enable business actors to develop and implement local policies applying the new technology for business purposes. The paper focuses on how some yet to be settled global policy issues affect local policies.

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