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- Multimedia (2)
- Video streaming (2)
- WLAN (2)
- Adaptive video streaming (1)
- Data transmission (1)
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- Differentiated prioritization scheme (1)
- End-user perceived quality (1)
- Grading scheme (1)
- IEEE 802.11e EDCA (1)
- IEEE802.11e WLAN (1)
- Location based services (1)
- Location prediction (1)
- Model reduction (1)
- Nonlinear systems (1)
- Performance evaluation (1)
- QoS (1)
- Quality of Service (1)
- Quality of service (1)
- Speech communication (1)
- VoIP over wireless LAN (VoWLAN) (1)
- Voice transmission quality (1)
- WiFi positioning (1)
- Wireless Home Area Network (1)
- Wireless LAN (1)
Articles 1 - 12 of 12
Full-Text Articles in Engineering
Wireless Positioning Techniques: A Developer's Update, Seamus Rooney, Keith Gardiner, James Carswell
Wireless Positioning Techniques: A Developer's Update, Seamus Rooney, Keith Gardiner, James Carswell
Conference papers
This paper describes the current efforts to develop an open source, privacy sensitive, location determination software component for mobile devices. Currently in mobile computing, the ability of a mobile device to determine its own location is becoming increasingly desirable as the usefulness of such a feature enhances many commercial applications. There have been numerous attempts to achieve this from both the network positioning perspective and also from the wireless beacon angle not to mention the integration of GPS into mobile devices. There are two important aspects to consider when using such a system which are privacy and cost. This paper …
The Effects Of Contention Among Stations On Video Streaming Applications Over Wireless Local Area Networks: An Experimental Approach, Nicola Cranley, Tanmoy Debnath
The Effects Of Contention Among Stations On Video Streaming Applications Over Wireless Local Area Networks: An Experimental Approach, Nicola Cranley, Tanmoy Debnath
Conference papers
Multimedia streaming applications have a large impact on the resource requirements of the WLAN. There are many variables involved in video streaming, such as the video content being streamed, how the video is encoded and how it is sent. This makes the role of radio resource management and the provision of QoS guarantees extremely difficult. For video streaming applications, packet loss and packets dropped due to excessive delay are the primary factors that affect the received video quality. In this paper, we experimentally analyse the effects of contention on the performance of video streaming applications with a given delay constraint …
Examination Of Energy And Group Velocities In Positive And Negative Index Chiral Materials With And Without Dispersion, Monish Ranjan Chatterjee, Partha P. Banerjee
Examination Of Energy And Group Velocities In Positive And Negative Index Chiral Materials With And Without Dispersion, Monish Ranjan Chatterjee, Partha P. Banerjee
Electrical and Computer Engineering Faculty Publications
Concepts of energy and group velocities, Poynting and propagation vectors are examined for both positive and negative index materials. Known definitions for these entities are explored in terms of the interplay of chirality and dispersion.
Experimental Tuning Of The Aifsn Parameter To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Experimental Tuning Of The Aifsn Parameter To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally study the impact of one EDCA parameter, namely AIFSN on a mixed voice/data wireless transmission. In particular we investigate how the tuning of this parameter affects both the voice transmission quality and background data throughput. We predict end-to-end voice transmission quality from time varying transmission impairements using the latest Appendix to the ITU-T E-model. Our experiemental results show that the tuning of the AIFSN parameter can successfully prioritize voice transmission over data in a real 802.11e network. To the best of our knowledge this is the first experimental investigation on tuning of MAC layer parameters …
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally study the impact of two EDCA parameters, namely AIFSN and CWmin, on a mixed voice/data wireless transmission. In particular we investigate how the tuning of these parameters affects both the voice transmission quality and background data throughput. We predict end-to-end voice transmission quality from time varying transmission impairments using the latest Appendix to the ITU-T E-model. Our experimental results show that the tuning of the EDCA parameters can be used to successfully prioritize voice transmission over data in real 802.11e networks. We also demonstrate that the AIFSN parameter more effectively protects voice calls against background …
An Experimental Investigation Of Parallel Multimedia Streams Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Tanmoy Debnath, Mark Davis
An Experimental Investigation Of Parallel Multimedia Streams Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Tanmoy Debnath, Mark Davis
Conference papers
In this paper we perform an experimental investigation of the IEEE 802.11 TXOP facility to enhance the transmission of parallel multimedia streaming sessions through efficient bandwidth reservation and explicitly consider both the audio and video streams. The delay constraints associated with the audio and video streams that comprise a multimedia session pose the greatest challenge since real-time multimedia is particularly sensitive to delay as the packets require a strict bounded end-to-end delay. We show how the TXOPlimit parameter can be efficiently dimensioned to reduce the tranmission delay for the video frames. Due to tis frame-based nature, video applications are considered …
Analysis Of Beam Propagation In 90-Degree Holographic Recording And Readout Using Transfer Functions And Numerical 2-D-Laplace Inversion, Monish Ranjan Chatterjee, Partha P. Banerjee, George Nehmetallah
Analysis Of Beam Propagation In 90-Degree Holographic Recording And Readout Using Transfer Functions And Numerical 2-D-Laplace Inversion, Monish Ranjan Chatterjee, Partha P. Banerjee, George Nehmetallah
Electrical and Computer Engineering Faculty Publications
Recently, 2-D-Laplace analysis of recording and readout of edge-holograms was reported. Numerical Laplace inversion was examined for simple test cases. Inversion algorithms are applied to examine beam shaping and distortion in photovoltaic and photorefractive materials.
User Quality Of Experience-Aware Multimedia Streaming Over Wireless Home Area Network, Gabriel-Miro Muntean, Nicola Cranley
User Quality Of Experience-Aware Multimedia Streaming Over Wireless Home Area Network, Gabriel-Miro Muntean, Nicola Cranley
Conference papers
For multimedia streaming over wireless networks, there is a trade-off between the capacity of the wireless links and the end-user perceived-quality, which can be affected by the compression scheme used, content characteristics and adaptation algorithm (if any). In this paper, this trade-off is investigated for streaming various motion content multimedia over an IEEE 802.11b-based Wireless-Home Area Network using the Quality-Oriented Adaptation Scheme (QOAS). QOAS performance is compared to that of a non-adaptive scheme when using MPEG-2 and MPEG-4 encoding in terms of average end-user perceived quality, number of streaming sessions concurrently supported, loss rate, delay, jitter and total throughput. Simulation …
Atmospheric Turbulence Compensation Of Point Source Images Using Asynchronous Stochastic Parallel Gradient Descent Technique On Amos 3.6 M Telescope, Mikhail Vorontsov, Jim F. Riker, Gary W. Carhart, Venkata S. Rao Gudimetla, Leonid A. Beresnev, Thomas Weyrauch
Atmospheric Turbulence Compensation Of Point Source Images Using Asynchronous Stochastic Parallel Gradient Descent Technique On Amos 3.6 M Telescope, Mikhail Vorontsov, Jim F. Riker, Gary W. Carhart, Venkata S. Rao Gudimetla, Leonid A. Beresnev, Thomas Weyrauch
Electrical and Computer Engineering Faculty Publications
The Stochastic Parallel Gradient Descent Technique-based Adaptive Optics (SPGD-AO) system described in this presentation does not use a conventional wavefront sensor. It uses a metric signal collected by a single pixel detector placed behind a pinhole in the image plane to drive three deformable mirrors (DMs). The system is designed to compensate the image for turbulence effects. The theory behind this method is described in detail in [1]. However this technique, while widely simulated and tested in the laboratory, was not yet verified in astronomical field site experiments. During the month of May 2007, a series of experiments with SPGD-AO …
Adaptive Optics Performance Over Long Horizontal Paths: Aperture Effects In Multi-Conjugate Adaptive Optical Systems, Miao Yu, Mikhail Vorontsov, Svetlana Lachinova, Jim F. Riker, Venkata S. Rao Gudimetla
Adaptive Optics Performance Over Long Horizontal Paths: Aperture Effects In Multi-Conjugate Adaptive Optical Systems, Miao Yu, Mikhail Vorontsov, Svetlana Lachinova, Jim F. Riker, Venkata S. Rao Gudimetla
Electrical and Computer Engineering Faculty Publications
We analyze various scenarios of the aperture effects in adaptive optical receiver-type systems when inhomogeneities of the wave propagation medium are distributed over long horizontal propagation path, or localized in a few thin layers remotely located from the receiver telescope pupil. Phase aberration compensation is performed using closed-loop control architectures based on phase conjugation and decoupled stochastic parallel gradient descent (DSPGD) control algorithms. Both receiver system aperture diffraction effects and the impact of wave-front corrector position on phase aberration compensation efficiency are analyzed for adaptive systems with single or multiple wave-front correctors.
Krylov Subspaces From Bilinear Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov
Krylov Subspaces From Bilinear Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov
Articles
For efficient simulation of state-of-the-art dynamical systems as arise in all aspects of engineering, the development of reduced-order models is of paramount importance. While linear reduction techniques have received considerable study, increasingly nonlinear model reduction is becoming a significant field of interest. From a circuits and systems viewpoint, systems involving micromachined devices or systems involving mixed technologies necessitate the development of reduced-order nonlinear models. From a control systems viewpoint, the design of controllers for nonlinear systems is greatly facilitated by nonlinear model reduction strategies. To this end, the paper proposes two novel model-reduction strategies for nonlinear systems. The first involves …
Study Of Soliton Stabilization In D+1 Dimensions Using Novel Analytical And Numerical Techniques, George Nehmetallah, Partha P. Banerjee
Study Of Soliton Stabilization In D+1 Dimensions Using Novel Analytical And Numerical Techniques, George Nehmetallah, Partha P. Banerjee
Electrical and Computer Engineering Faculty Publications
In this Chapter, we provide a brief review of the underlying nonlinear Schrödinger and associated equations that model spatio-temporal propagation in one and higher dimensions in a nonlinear dispersive environment. Particular attention is given to fast adaptive numerical techniques to solve such equations, and in the presence of dispersion and nonlinearity management, saturating nonlinearity and nonparaxiality. A unique variational approach is also outlined which helps in determining the ranges of nonlinearity and dispersion parameters to ensure stable solutions of the nonlinear equations. The propagation of 3+1 dimensional spatio-temporal pulses, or optical bullets is also modeled using a fast adaptive split-step …