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Interconnection networks within modern data centers suffer from bandwidth and scalability limitations, and important power consumption. Optical switching solutions can help to overcome such issues when properly designed and optimized. This paper discusses three areas of improvement beyond state of the art: i) the use of more energy-efficient optical devices to realize high-capacity and energy-efficient...
In this paper, we analyze the symbol-error rate of a two-hop fixed-gain amplify-and-forward OFDM relay network when nonlinear distortion, as a consequence of relay amplifier saturation, is considered at the relay. We begin by constructing a theoretical model of the system. Due to the Gaussianity of OFDM waveforms, we are able to employ Bussgang's theorem in our model, which enables the calculation...
In this paper, we present a new FDMA-PON (Frequency Division Multiple Access — Passive Optical Network) architecture proposed by the FP7 EU STREP project titled “FABULOUS”. The paper is focused on the upstream transmission, based on an innovative reflective optical network unit (R-ONU). A detailed theoretical analysis is first presented and used to optimize the system parameters, then we show the...
In this paper, we describe recent architectural and technological advances of the end to end optical network architecture proposed by the DISCUS project (the DIStributed Core for unlimited bandwidth supply for all Users and Services). The two main targets of DISCUS are the principle of equivalence in the access and the reduction of optical-to-electronic conversions in the metro-core network. Technological...
Dense heterogeneous networks constitute the paradigm for the future networks. In fact, recent studies demonstrate that the data traffic demand increases exponentially and the traditional cellular networks are not able to provide enough capacity. For this reason operators and standardisation bodies are particularly eager to solve the problem, hence there is a lot of ongoing research on this direction...
The SI-SAP protocol interface, defined in the framework of the ETSI BSM architecture, has the function of logically separating the Satellite Dependent (SD) from Satellite Independent (SI) layers, thus enabling the implementation of powerful vertical QoS mapping strategies. The paper analyses the use of the SI-SAP interface over DVB-S2/RCS technology in particular with respect to QoS functionalities...
This paper proposes a next generation ubiquitous converged infrastructure to support Cloud and mobile Cloud computing services. The proposed infrastructure facilitates interconnection of fixed and mobile end users with computational resources through a heterogeneous network integrating optical metro and wireless access networks. To satisfy the low-latency requirements of content-rich mobile applications,...
Wireless Body Area Networks (WBANs) have recently received much attention due to the possibility to be used in healthcare applications. For these applications, link reliability and energy efficiency are critical issues, as in many cases, information carried can be vital for the patient and batteries cannot be easily replaced. The wireless on-body channel experiences significant temporal variation...
Based on the definition of the access network architecture and the forecast of voice and data traffic evolution, this paper derives engineering rules for radio network dimensioning of 3G femtocell-based access networks in isolated rural areas. Network dimensioning exercise focuses not only on the access network, but also on the necessary backhaul bandwidth and the required number of solar energy power...
In cognitive radio networks (CRNs), the awareness of the environment is fundamental to efficiently avoid harmful interference toward primary users (PUs) and to improve cognitive radio (CR) performance. Thus, estimating the PUs position, rather than just knowing its presence through traditional spectrum sensing, becomes a key challenge. In this paper a novel cooperative localization algorithm (CLA)...
An AF relay splits an FBMC transmission link into a two-hop channel. The receiver implements a parallel multistage FBMC demodulator/equalizer that is suitable for fading channels whose frequency response cannot be considered flat over the subcarriers. The signal quality at the output of such a receiver is characterized in terms of signal-to-noise-plus-distortion ratio (SNDR), that takes into account...
As agreed at international level, the most reliable way to exploit the white spaces (WS) of UHF band foresees the interrogation of a geolocation database. The database evaluates and provides to the white space devices (WSD) the allowable frequencies and the maximum value of emission power in the WSD position. The common approach adopted in Europe to estimate such limits is based on the definition...
Current over-provisioned and multi-tier data centre networks (DCN) deploy rigid control and management platforms, which are not able to accommodate the ever-growing workload driven by the increasing demand of high-performance data centre (DC) and cloud applications. In response to this, the EC FP7 project LIGHTNESS (Low Latency and High Throughput Dynamic Network Infrastructures for High Performance...
This paper addresses the novel notion of offering a radio access network as a service. Its components may be instantiated on general purpose platforms with pooled resources (both radio and hardware ones) dimensioned on-demand, elastically and following the pay-per-use principle. A novel architecture is proposed that supports this concept. The architecture's success is in its modularity, well-defined...
We study the dynamic spectrum aggregation and allocation problem in cognitive radio networks (CRNs). When the available spectrum is fragmented and the bandwidth of the spectrum holes is narrow, spectrum aggregation can be a solution to use multiple holes. Since the spectrum holes can have different bandwidth and cognitive radios can dynamically adjust the centre frequency and the bandwidth for each...
Elastic optical networks represent one of the most promising candidates for the imminent upgrade of current fixed-grid based optical systems. This novel architecture based on high efficient spectrum allocation (i.e. higher capacity), is necessary to cope with foreseen future exponential increase of Internet traffic. This work discusses the influence of hardware components on the transmission performance...
We present a new PLNC scheme based on the recently developed compute-and-forward (C&F) paradigm and low density lattice codes (LDLC). LDLC possesses high coding gain and good algebraic structure which is inherently suitable for C&F. We also show that the ring-based constellation can be used to improve the average rate per dimension.
In this paper, we present a radio resource allocation algorithm based on interference alignment (IA) for orthogonal frequency division multiplexing (OFDM) and filter bank multicarrier (FBMC) based MIMO cognitive radio (CR) systems. The algorithm provides the opportunity for all secondary users to share the available subcarriers simultaneously using IA technique. Besides, it allocates the power budget...
We consider the problem of secret communication through a relay assisted downlink cognitive interference channel in which secondary base station (SBS) is allowed to transmit simultaneously with the primary base station (PBS) over the same channel instead of waiting for an idle channel which is traditional for a cognitive radio. We propose a cooperative jamming (CJ) scheme to improve the secrecy rate...
Cloud applications and the global delivery of Ethernet services require a scalable, reliable, virtualizable and cost/energy efficient optical transport infrastructure able to support data rates beyond 100 Gb/s. The ICT STRAUSS project addresses the requirement of future optical infrastructures for Ethernet transport beyond 100 Gb/s, by combining two network switching technologies, namely Optical Packet...
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