The Experts below are selected from a list of 49788 Experts worldwide ranked by ideXlab platform

Mahbub Hassan - One of the best experts on this subject based on the ideXlab platform.

  • VTC Spring - Fairness Control by Mobile Routers in On-Board Communication Networks
    2007 IEEE 65th Vehicular Technology Conference - VTC2007-Spring, 2007
    Co-Authors: Adeel Baig, Lavy Libman, Mahbub Hassan
    Abstract:

    Communication solutions for passengers on public transport vehicles, in the form of on-Board networks connected to the Internet via a mobile router (MR) and a wireless link, are increasingly offered by public transport providers in many countries. An important challenge in such networks is to guarantee a fair access to the scarce wireless bandwidth by all on-Board users, particularly in networks with multiple wireless interfaces. Accordingly, we consider an active fairness control scheme, where the MR transparently overrides the TCP advertised receiver window size to limit the transmission rates of on-Board TCP connections to their fair share. We focus on the overhead that this scheme places on the mobile router and the wireless interface, due to the need for the MR to estimate the round-trip time (RTT) of each on-Board connection. We investigate the performance of three strategies that differ in the timing of RTT estimations, and show that a fairness target-based strategy, which continuously monitors the ongoing fairness index and invokes an RTT reestimation whenever it drops below a predetermined value, consistently achieves a significant improvement in fairness for only a mild overhead cost.

  • Performance Enhancement of On-Board Communication Networks Using Outage Prediction
    IEEE Journal on Selected Areas in Communications, 2006
    Co-Authors: Adeel Baig, Lavy Libman, Mahbub Hassan
    Abstract:

    A research area that has become increasingly important in recent years is that of on-Board mobile Communication, where users on a vehicle are connected to a local network that attaches to the Internet via a mobile router and a wireless link. In this architecture, link disruptions (e.g., due to signal degradation) may have an immediate impact on a potentially large number of connections. We argue that the advance knowledge of public transport routes, and their repetitive nature, allows a certain degree of prediction of impending link disruptions, which can be used to offset their catastrophic impact. Focusing on the transmission control protocol (TCP) and its extension known as Freeze-TCP, we present a detailed analysis of the performance improvement of TCP connections in the presence of disruption prediction. In particular, we propose a Markov model of Freeze-TCP that captures both the TCP behavior and the prediction+"freezing" feature and, using simulations, show that it accurately predicts the performance of the protocol. Our results demonstrate the significant throughput improvement that can be gained by disruption prediction, even with random packet losses or imperfect timing of the predicted disruptions

Michael Jenning - One of the best experts on this subject based on the ideXlab platform.

  • Integrated Butler Matrix and $1\times 4$ Antenna Array for Board-to-Board Communication in the mmWave-range
    2018 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT), 2018
    Co-Authors: Bernhard Klein, Michael Jenning, Ronny Hahnel, Dirk Plettemeier
    Abstract:

    An integrated butler matrix with a $1\times 4$ antenna array consisting of log-spiral antenna elements is presented. The design is taped-out in a state-of-the-art indium phosphide technology of Teledyne. By the implementation of the butler matrix as a passive phase shifting element, the whole system enables beam-steering capabilities in the frequency range from 165 GHz to 195 GHz. Therefore, this system allows the design of adaptive and energy-efficient wireless links for Board-to-Board Communication in the mmW-range.

  • energy efficient transceivers for ultra highspeed computer Board to Board Communication
    IEEE International Conference on Ubiquitous Wireless Broadband, 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

  • ICUWB - Energy-Efficient Transceivers for Ultra-Highspeed Computer Board-to-Board Communication
    2015 IEEE International Conference on Ubiquitous Wireless Broadband (ICUWB), 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

  • Wideband half-cloverleaf shaped on-chip antenna for 160 GHz – 200 GHz applications
    2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2014
    Co-Authors: Bernhard Klein, Michael Jenning, Patrick Seiler, Dirk Plettemeier
    Abstract:

    A wideband on-chip antenna for the frequency range of 160GHz to 200 GHz has been developed and taped out in the IHP SG13 process. Simulation results show a maximum absolute gain of 2.2 dBi at 200 GHz. The antenna is designed for high-speed Board-to-Board Communication.

  • optimal antenna positioning for wireless Board to Board Communication using a butler matrix beamforming network
    International ITG Workshop on Smart Antennas, 2013
    Co-Authors: Johannes Israel, Michael Jenning, Andreas Fischer, John Martinovic, Lukas Landau
    Abstract:

    For wireless Board-to-Board Communication the problem of an optimal positioning of antenna arrays on two Boards facing each other is described, where each antenna array uses the same kind of Butler matrix beamforming network. We discuss possible design criteria for the positioning problem. To obtain a position with both a high response and a low pathloss for as many as possible links we introduce a corresponding optimization problem and show how it can be solved.

M Schroter - One of the best experts on this subject based on the ideXlab platform.

  • energy efficient transceivers for ultra highspeed computer Board to Board Communication
    IEEE International Conference on Ubiquitous Wireless Broadband, 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

  • ICUWB - Energy-Efficient Transceivers for Ultra-Highspeed Computer Board-to-Board Communication
    2015 IEEE International Conference on Ubiquitous Wireless Broadband (ICUWB), 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

Adeel Baig - One of the best experts on this subject based on the ideXlab platform.

  • VTC Spring - Fairness Control by Mobile Routers in On-Board Communication Networks
    2007 IEEE 65th Vehicular Technology Conference - VTC2007-Spring, 2007
    Co-Authors: Adeel Baig, Lavy Libman, Mahbub Hassan
    Abstract:

    Communication solutions for passengers on public transport vehicles, in the form of on-Board networks connected to the Internet via a mobile router (MR) and a wireless link, are increasingly offered by public transport providers in many countries. An important challenge in such networks is to guarantee a fair access to the scarce wireless bandwidth by all on-Board users, particularly in networks with multiple wireless interfaces. Accordingly, we consider an active fairness control scheme, where the MR transparently overrides the TCP advertised receiver window size to limit the transmission rates of on-Board TCP connections to their fair share. We focus on the overhead that this scheme places on the mobile router and the wireless interface, due to the need for the MR to estimate the round-trip time (RTT) of each on-Board connection. We investigate the performance of three strategies that differ in the timing of RTT estimations, and show that a fairness target-based strategy, which continuously monitors the ongoing fairness index and invokes an RTT reestimation whenever it drops below a predetermined value, consistently achieves a significant improvement in fairness for only a mild overhead cost.

  • Performance Enhancement of On-Board Communication Networks Using Outage Prediction
    IEEE Journal on Selected Areas in Communications, 2006
    Co-Authors: Adeel Baig, Lavy Libman, Mahbub Hassan
    Abstract:

    A research area that has become increasingly important in recent years is that of on-Board mobile Communication, where users on a vehicle are connected to a local network that attaches to the Internet via a mobile router and a wireless link. In this architecture, link disruptions (e.g., due to signal degradation) may have an immediate impact on a potentially large number of connections. We argue that the advance knowledge of public transport routes, and their repetitive nature, allows a certain degree of prediction of impending link disruptions, which can be used to offset their catastrophic impact. Focusing on the transmission control protocol (TCP) and its extension known as Freeze-TCP, we present a detailed analysis of the performance improvement of TCP connections in the presence of disruption prediction. In particular, we propose a Markov model of Freeze-TCP that captures both the TCP behavior and the prediction+"freezing" feature and, using simulations, show that it accurately predicts the performance of the protocol. Our results demonstrate the significant throughput improvement that can be gained by disruption prediction, even with random packet losses or imperfect timing of the predicted disruptions

Dirk Plettemeier - One of the best experts on this subject based on the ideXlab platform.

  • Integrated Butler Matrix and $1\times 4$ Antenna Array for Board-to-Board Communication in the mmWave-range
    2018 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT), 2018
    Co-Authors: Bernhard Klein, Michael Jenning, Ronny Hahnel, Dirk Plettemeier
    Abstract:

    An integrated butler matrix with a $1\times 4$ antenna array consisting of log-spiral antenna elements is presented. The design is taped-out in a state-of-the-art indium phosphide technology of Teledyne. By the implementation of the butler matrix as a passive phase shifting element, the whole system enables beam-steering capabilities in the frequency range from 165 GHz to 195 GHz. Therefore, this system allows the design of adaptive and energy-efficient wireless links for Board-to-Board Communication in the mmW-range.

  • energy efficient transceivers for ultra highspeed computer Board to Board Communication
    IEEE International Conference on Ubiquitous Wireless Broadband, 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

  • ICUWB - Energy-Efficient Transceivers for Ultra-Highspeed Computer Board-to-Board Communication
    2015 IEEE International Conference on Ubiquitous Wireless Broadband (ICUWB), 2015
    Co-Authors: Michael Jenning, Bernhard Klein, Ronny Hahnel, Dirk Plettemeier, David Fritsche, Gregor Tretter, Corrado Carta, Frank Ellinger, Tobias Nardmann, M Schroter
    Abstract:

    Enabling the vast computational and throughput requirements of future high performance computer systems and data centers requires innovative approaches. In this paper, we will focus on the Communication between computer Boards. One alternative to the bottleneck presented by copper wire based cable-bound Communication is the deployment of wireless links between nodes consisting of processors and memory on different Boards in a system. In this paper, we present an interdisciplinary approach that targets an integrated wireless transceiver for short-range ultra-high speed computer Board-to-Board Communication. Based on our achieved results and current developments, we will also estimate energy consumption of such a transceiver.

  • Wideband half-cloverleaf shaped on-chip antenna for 160 GHz – 200 GHz applications
    2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 2014
    Co-Authors: Bernhard Klein, Michael Jenning, Patrick Seiler, Dirk Plettemeier
    Abstract:

    A wideband on-chip antenna for the frequency range of 160GHz to 200 GHz has been developed and taped out in the IHP SG13 process. Simulation results show a maximum absolute gain of 2.2 dBi at 200 GHz. The antenna is designed for high-speed Board-to-Board Communication.