Digital Pre-distortion using Legendre Polynomials for Band 25 Transmitters

  • Reddy A.

In this paper, we discuss the implementation of a digital pre-distorter for wideband wireless applications using Legendre polynomials as the orthogonal polynomial basis. The implementation discusses a multicarrier configuration using a wideband amplifier. Structures based on polynomial functions are widely used for both power amplifiers (PAs) and pre-distorters. Higher non-linear ...

BRACE: Cloud-based Software Reliability Assurance

  • Asthana A.
  • Mijumbi R.
  • Okumoto K.

The evolution towards virtualized network functions (VNFs) is expected to enable service agility within the telecommunications industry. To this end, the software (or VNFs) from which such services are composed must be developed and delivered over very short time scales. In order to guarantee the required levels of software quality ...

Coherent frequency tuneable thz wireless signal generation using an optical phase lock loop system

  • Balakier K.
  • Fice M.
  • Graham C.
  • Ponnampalam L.
  • Renaud C.
  • Seeds A.
  • Shams H.
  • Van Dijk F.

We demonstrate experimentally, for the first time, the photonic generation of a continuous tunable THz wireless signal based on using an optical phase lock loop (OPLL) subsystem and optical frequency comb generator (OFCG). The OPLL is employed to select one line from the optical comb and shift it by the ...

Electro-Absorption modulator-based optoelectronic oscillator

  • Alouini M.
  • Debregeas H.
  • Lanteri D.
  • Primiani P.
  • Van Dijk F.

In the perspective of a monolithic integration of an optoelectronic oscillator on photonic integrated circuits, we evaluate the performances of integrated DFB laser and electro-absorption modulator devices. For this purpose two identical chips have been used, the first for laser emission and amplitude modulation and the second for photo-detection. The ...

Analytics-Enhanced Automated Code Verification for Dependability of Software-Defined Networks

  • Jagadeesan L.
  • Mendiratta V.

Software-defined networking (SDN) is a key emerging technology that enables networks to be programmed and dynamically reconfigured through software-based network applications. This programability also significantly increases the exposure of these networks to software application faults, which can compromise or crash the underlying SDN network. It is thus imperative to detect ...

360-Degree Video Streaming and its Subjective Quality

Traditional challenges for deploying end-to-end streaming systems are made harder when considering 360-degree media content. One of these challenges relates to the lack of commonly accepted standardized methodologies for subjective 360-degree video quality assessment, especially oriented towards streaming services. The contribution of this paper falls in the area of subjective ...

Passive cooling and thermal management in data centers

  • Conte A.
  • Le Masson S.
  • Louahlia H.
  • Nadjahi C.

This article introduces the first experimental and analytical results of a two-phase thermosyphon loop, designed to cool a data center. This loop, composed by a mini-channels evaporator and an air condenser, is a passive system capable of decreasing electricity consumption in a data center. An analytical model has been developed ...

Cross-correlation based clustering and dimension reduction on multivariate time series for KPIs in a data processing system

  • Egri A.
  • Horváth I.
  • Kovacs F.
  • Molontay R.
  • Varga K.

In this paper, we investigate multi-dimensional time series data and we introduce a graph based clustering approach using the cross-correlation between the time series. The procedure is applied to Key Performance Indicators (KPIs) measured during a specific data processing system in order to identify connections between the various KPIs. The ...

Nonlinear Characterisation for Microstrip Circuits with Low Passive Intermodulation

  • Kozlov Dmitry
  • Schuchinsky A.
  • Shitvov A.

This paper presents a new methodology for experimental charaterisation of distributed nonlinearity in microstrip circuits fabricated on commercial grade microwave laminate materials. The circuits exhibit excessive intermodulation response when subject to relatively high power transmit multi-carrier waveforms. Weak intermodulation products generated in passive circuits may cause strong interference in the ...

An RNS-based forwarding approach to implement SFC

Because of the more and more diversified service, SFC needs to be dynamically and feasibly implemented. Thanks to NFV and SDN ideas, the new SFC architecture is defined to meet the requirements in the IETF. Based on the OpenFlow, the approach of the single flow table is used to implement ...

Tailor-made tuneable dielectric and optical characteristics of inorganic electro-chromic materials

  • Bulja S.
  • Kopf R.

Electro-chromic materials (EC) have the ability to reversibly change their optical properties by charge insertion/extraction and have, since their discovery by Deb, been chiefly used in applications related to display technology. Examples are many - smart windows and mirrors and active optical filters being some of them. Owing to their ...

Network Service Descriptors as a Factory - Agile Networking for differentiating MSO Business Services

  • Acke W.
  • Fagadar M.
  • Six E.
  • Vanderstraeten H.

Orchestration has become an overloaded word in the industry. While Network Orchestration and Application Orchestration share a lot of technologies coming from the domains of SDN and NFV, the 2 approaches serve different objectives. The paper will specifically address Network Orchestration, aiming at launching new revenue generating Business Connectivity services ...

Sustained Throughput Requirements for Future Residential Broadband Service - Traffic Model for Bandwidth Estimates

  • Kapauan P.
  • Mukhopadhyay A.
  • Wellen J.

This paper presents a model to estimate the 10 years maximum sustained throughput requirements for residential broadband services. The model is used to estimate the maximum throughputs during busy hour and to assess how upper throughput percentiles compare to mean expected value.

Comparison of HEVC coding schemes for tile-based viewport-adaptive streaming of omnidirectional video

Virtual reality applications make use of 360-degree panoramic or omnidirectional video with high resolution and high frame rate in order to create the immersive experience to the user. The user views only a portion of the captured 360-degree scene at each time instant, hence streaming the whole omnidirectional video in ...

High responsivity coherent photonic receiver integrating an SOA, a 90° hybrid and high speed UTC photodiodes

  • Achouche M.
  • Caillaud C.
  • Mekhazni K.
  • Paret J.
  • Pommereau F.
  • Santini G.

We demonstrate a monolithically integrated coherent receiver on an InP substrate with a SOA preamplifier, a 90° optical hybrid and four 40 GHz UTC photodiodes. Record performances with responsivity above 4 A/W with low imbalance <1 dB and error free detection of 32 Gbauds QPSK signals were simultaneously demonstated

Gate-Controlled Kondo Effect in a Single Molecule Transistor with Elliptical Ferromagnetic Leads

  • Hu T.
  • Scott G.

We present low temperature transport measurements of C60-based single molecule transistors fabricated using ferromagnetic break junction devices with planar elliptical leads, revealing a gate-modulated single channel spin-1/2 Kondo effect. The shape anisotropy and dipole interaction of the source and drain electrodes allows for the relative alignment of their respective magnetic ...

Visualization of the wake behind a sliding bubble

  • Davis I.
  • Grennan K.
  • Meehan R.
  • Murray D.
  • Nolan K.

In this work, Schlieren measurements are presented for the wake of an air bubble sliding under a heated, inclined surface in quiescent water to provide new insights into the intricate sliding bubble wake structure and the associated convective cooling process. This is a two-phase flow configuration that is pertinent to ...

Investigating activity zones on smartphones: An empirical study with older adults

This paper investigates and extends existing knowledge on older adults' (65+) gestural interaction with smartphones. Specifically, it looks at the effect touch targets location has on older adults' performance of tap and swipe gestures. Two separate experiments, each with 40 participants, showed older adults' performance for tap is best toward ...

Edge Computing in the ePC --- A Reality Check

  • Abe Y.
  • Hadzic I.
  • Woithe H.

Mobile Edge Computing (MEC) has received much attention from the research community in recent years. A significant part of the published work has studied the telecom-centric MEC architecture, which assumes that the computing resource is located at the edge of the mobile access network (e.g., the Evolved Packet Core), typically ...

Vectoring-Based Dynamic Spectrum Management for Multi-User Full-Duplex Transmission

  • Lanneer W.
  • Maes J.
  • Moonen M.
  • Tsiaflakis P.

Full-duplex transmission is a new challenging technique emerging in DSL networks that may double the spectral efficiency by transmitting in the downstream (DS) and upstream (US) at the same time on identical frequencies. Unfortunately, this leads to severe near-end crosstalk (NEXT) interference in addition to the conventional far-end crosstalk (FEXT) ...