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Frank H. P. Fitzek

Other affiliations: Aalborg University, Freescale Semiconductor, Siemens  ...read more
Bio: Frank H. P. Fitzek is an academic researcher from Dresden University of Technology. The author has contributed to research in topics: Linear network coding & Wireless network. The author has an hindex of 38, co-authored 558 publications receiving 8404 citations. Previous affiliations of Frank H. P. Fitzek include Aalborg University & Freescale Semiconductor.


Papers
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Journal ArticleDOI
TL;DR: A publicly available library of frame size traces of long MPEG-4 and H.263 encoded videos, generated at the Technical University Berlin are presented and a thorough statistical analysis of the traces are conducted.
Abstract: MPEG-4 and H.263 encoded video is expected to account for a large portion of the traffic in future wireline and wireless networks. However, due to a lack of sufficiently long frame size traces of MPEG-4 and H.263 encoded videos, most network performance evaluations currently use MPEG-1 encodings. We present and study a publicly available library of frame size traces of long MPEG-4 and H.263 encoded videos, which we have generated at the Technical University Berlin. The frame size traces have been generated from MPEG-4 and H.263 encodings of over 10 video sequences each 60 minutes long. We conduct a thorough statistical analysis of the traces.

710 citations

BookDOI
01 Jan 2006
TL;DR: This book summarizes the strength of cooperation for upcoming generation of wireless communication systems, clearly motivating the use of cooperative techniques and pointing out that cooperation will become one of the key technologies enabling 4G and beyond.
Abstract: Cooperation in Wireless Networks: Principles and Applications covers the underlying principles of cooperative techniques as well as several applications demonstrating the use of such techniques in practical systems. The work is written in a collaborative manner by several authors from Asia, America, and Europe. Twenty chapters introduce and discuss in detail the main cooperative strategies for the whole communication protocol stack from the application layer down to the physical layer. Furthermore power saving strategies, security, hardware realization, and user scenarios for cooperative communication systems are introduced and discussed. The book also summarizes the strength of cooperation for upcoming generation of wireless communication systems, clearly motivating the use of cooperative techniques and pointing out that cooperation will become one of the key technologies enabling 4G and beyond. This book puts into one volume a comprehensive and technically rich view of the wireless communications scene from a cooperation point of view.

374 citations

Proceedings ArticleDOI
11 Jun 2006
TL;DR: In this paper, the authors advocate exploiting channel descriptor information in packet data communication networks to gain transmission capacity, where the channel descriptor (or character of the channel) can be used to convey data.
Abstract: In this paper we advocate exploiting channel descriptor information in packet data communication networks to gain transmission capacity. Besides the normal data transmission also the channel descriptor (or character of the channel) can be used to convey data. This novel access technique is suitable for wired as well as for wireless networks. By the example of a wireless spread spectrum system with pseudo?noise spreading sequences, we can report that a gain of nearly an order of magnitude in terms of capacity can be achieved compared to the standard spread spectrum transmission for a given scenario. Our approach is not limited to spread spectrum technologies, but applies to all systems with the property that the number of channel descriptors is larger than the actual number of simultaneously usable resources.

362 citations

Proceedings ArticleDOI
15 May 2011
TL;DR: In this survey, the energy consuming entities of a mobile device such as wireless air interfaces, display, mp3 player and others are measured and compared and allow the reader to understand what the energy hungry parts of aMobile device are and use those findings for the design of future mobile protocols and applications.
Abstract: The full degree of freedom in mobile systems heavily depends on the energy provided by the mobile phone's batteries. Their capacity is in general limited and for sure not keeping pace as the mobile devices are crammed up with new functionalities. The discrepancy of Moore's law, offering twice the processing power at least each second year, and the development in batteries, which did not even double over the last decade, makes a shift in researchers' way of designing networks, protocols, and the mobile device itself. The bottleneck to take care of in the design process of mobile systems is not only the wireless data rate, but even more the energy limitation as the customers ask for new energy-hungry services, e.g., requiring faster connections or even multiple air interfaces, and longer standby or operational times of their mobile devices at the same time. In this survey, the energy consuming entities of a mobile device such as wireless air interfaces, display, mp3 player and others are measured and compared. The presented measurement results allow the reader to understand what the energy hungry parts of a mobile device are and use those findings for the design of future mobile protocols and applications. All results presented in this work and further results are made public on our web page [2].

337 citations

Journal ArticleDOI
TL;DR: This article gives a pragmatic definition of 4G derived from a new user-centric methodology that considers the user as the "cornerstone" of the design and contributes to the identification of the real technical step-up of4G with respect to 3G.
Abstract: The ever-increasing growth of user demand, the limitations of the third generation of wireless mobile communication systems, and the emergence of new mobile broadband technologies on the market have brought researchers and industries to a thorough reflection on the fourth generation. Many prophetic visions have appeared in the literature presenting 4G as the ultimate boundary of wireless mobile communication without any limit to its potential, but in practical terms not giving any design rules and thus any definition of it. In this article we give a pragmatic definition of 4G derived from a new user-centric methodology that considers the user as the "cornerstone" of the design. In this way, we devise fundamental user scenarios that implicitly reveal the key features of 4G, which are then expressed explicitly in a new framework - the "user-centric" system - that describes the various level of interdependency among them. This approach consequently contributes to the identification of the real technical step-up of 4G with respect to 3G. Finally, an example of a potential 4G application is also given in order to demonstrate the validity of the overall methodology

183 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

Journal ArticleDOI
TL;DR: This paper provides a taxonomy based on the D2D communicating spectrum and review the available literature extensively under the proposed taxonomy to provide new insights into the over-explored and under- Explored areas that lead to identify open research problems of D1D communications in cellular networks.
Abstract: Device-to-device (D2D) communications was initially proposed in cellular networks as a new paradigm for enhancing network performance. The emergence of new applications such as content distribution and location-aware advertisement introduced new user cases for D2D communications in cellular networks. The initial studies showed that D2D communications has advantages such as increased spectral efficiency and reduced communication delay. However, this communication mode introduces complications in terms of interference control overhead and protocols that are still open research problems. The feasibility of D2D communications in Long-Term Evolution Advanced is being studied by academia, industry, and standardization bodies. To date, there are more than 100 papers available on D2D communications in cellular networks, but there is no survey on this field. In this paper, we provide a taxonomy based on the D2D communicating spectrum and review the available literature extensively under the proposed taxonomy. Moreover, we provide new insights into the over-explored and under-explored areas that lead us to identify open research problems of D2D communications in cellular networks.

1,784 citations

Journal ArticleDOI
TL;DR: In this article, a taxonomy based on the D2D communicating spectrum and review the available literature extensively under the proposed taxonomy is provided, which provides new insights to the over-explored and underexplored areas which lead to identify open research problems of D2DM communication in cellular networks.
Abstract: Device-to-Device (D2D) communication was initially proposed in cellular networks as a new paradigm to enhance network performance. The emergence of new applications such as content distribution and location-aware advertisement introduced new use-cases for D2D communications in cellular networks. The initial studies showed that D2D communication has advantages such as increased spectral efficiency and reduced communication delay. However, this communication mode introduces complications in terms of interference control overhead and protocols that are still open research problems. The feasibility of D2D communications in LTE-A is being studied by academia, industry, and the standardization bodies. To date, there are more than 100 papers available on D2D communications in cellular networks and, there is no survey on this field. In this article, we provide a taxonomy based on the D2D communicating spectrum and review the available literature extensively under the proposed taxonomy. Moreover, we provide new insights to the over-explored and under-explored areas which lead us to identify open research problems of D2D communication in cellular networks.

1,590 citations

Proceedings ArticleDOI
25 May 2005
TL;DR: This paper proposes four different jamming attack models that can be used by an adversary to disable the operation of a wireless network, and evaluates their effectiveness in terms of how each method affects the ability of a Wireless node to send and receive packets.
Abstract: Wireless networks are built upon a shared medium that makes it easy for adversaries to launch jamming-style attacks. These attacks can be easily accomplished by an adversary emitting radio frequency signals that do not follow an underlying MAC protocol. Jamming attacks can severely interfere with the normal operation of wireless networks and, consequently, mechanisms are needed that can cope with jamming attacks. In this paper, we examine radio interference attacks from both sides of the issue: first, we study the problem of conducting radio interference attacks on wireless networks, and second we examine the critical issue of diagnosing the presence of jamming attacks. Specifically, we propose four different jamming attack models that can be used by an adversary to disable the operation of a wireless network, and evaluate their effectiveness in terms of how each method affects the ability of a wireless node to send and receive packets. We then discuss different measurements that serve as the basis for detecting a jamming attack, and explore scenarios where each measurement by itself is not enough to reliably classify the presence of a jamming attack. In particular, we observe that signal strength and carrier sensing time are unable to conclusively detect the presence of a jammer. Further, we observe that although by using packet delivery ratio we may differentiate between congested and jammed scenarios, we are nonetheless unable to conclude whether poor link utility is due to jamming or the mobility of nodes. The fact that no single measurement is sufficient for reliably classifying the presence of a jammer is an important observation, and necessitates the development of enhanced detection schemes that can remove ambiguity when detecting a jammer. To address this need, we propose two enhanced detection protocols that employ consistency checking. The first scheme employs signal strength measurements as a reactive consistency check for poor packet delivery ratios, while the second scheme employs location information to serve as the consistency check. Throughout our discussions, we examine the feasibility and effectiveness of jamming attacks and detection schemes using the MICA2 Mote platform.

1,350 citations