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Some of the future wireless networks are related to the provision of higher data rates and lower energy consumption. In contrast to the clear increasing spectrum demand, bandwidth is a limited resource. Cooperative diversity allows to increase the spectral efficiency and the reliability of the communication. However, in scenarios with high node density and high mobile data traffic volume the collaboration...
In this paper, we address the issue of profiling users over the Internet using meta-data logs derived from network flow data (hence preserving a high degree of privacy). In this broader context, we specifically aim to empirically demonstrate that Internet volume and time of usage of humans do exhibit repeatable behavior over time. In our experimental study, Internet usage statistics of octets and...
A greenhouse monitoring system using hierarchical wireless sensor network (WSN) is presented in this paper. The main parameters required to monitor and control a greenhouse are air humidity and temperature, ground moisture and environment lightness. For the data gathering of these parameters, a hierarchical WSN is presented in this work. In this configuration, the sensors, aggregated with all gathering...
In this paper a practical application of an electrooptical communication system based on external modulation is reported. The sixteen ATSC TV-channels located at 2.4 GHz, were transmitted over a 30 km of standard optical fiber. The transmitted TV-signal uses Single-Side Band Full Carrier (SSBFC) modulation, allowing in this way an adequate management of the transmitted power and the bandwidth. The...
The introduction of Space division multiplexing (SDM) in optical networks brings new challenges for protection of networks since a lightpath can span multiple cores. In this paper, we investigate the problem of dynamic protection against two simultaneous failures in spacial division multiplexing elastic optical networks. For that, we propose a new path-protection sharing spectrum and straddling p-cycle...
The VST-TDMA access protocol has shown to have many advantages over existing protocols in centralized (star) wireless network architectures. As most data-link layer protocols, it does not have a recovery feature as data integrity is supervised by the connection-oriented transport protocols. Nevertheless, VST-TDMA possesses the flexibility to easily incorporate a retransmission feature that allows...
Low voltage, in-home power-line communications (PLC) networks allow direct communication between smart meters (SM) and in-home devices (IHD). In order to minimize security issues, in many deployment scenarios transmission takes place only towards the IHD to display consumption data, with no backwards channel. As a result, channel estimation is difficult and it is necessary to use robust transmission...
The shifting towards New Radio waveforms for future cellular networks will require a smooth transition from the existing 4G physical layer (PHY), which is based on the LongTerm Evolution-Advance (LTE-A) system. This will allow the service provider to develop less cost multi-standard devices that rely on the same master clock compatibility and with the same time-frequency grid representation of the...
This article presents the analysis of the influence of environmental variables on the received signal power from a point to point wireless link (f = 5.52 GHz) in a tropical urban environment, in the cities of Guayaquil and Duran, of Ecuador. The study included data of five variables such as relative humidity (HR), atmospheric temperature (T), solar radiation (RS), rainfall (Pr) and signal power (P)...
Bringing to the market intelligent vehicles is one of the current challenges faced by car manufacturers. These vehicles must be able to communicate in order to cooperate and be more effective. The issue of inter-vehicle communications is an active research topic. This paper proposes a reliable geographical broadcasting protocol which has a twofold goal: limiting the risk of interference and reducing...
All-optical (transparent) wavelength-division multiplexing (WDM), a cost-effective and low power consumption solution for core transport networks, suffers from physical-layer impairments that accumulate along optical paths. In this context, it is important to find dynamic routing schemes with good performance that can consider the optical-layer constraints. In this paper, we propose the alternative...
In digital communication systems the use of filters that fulfill the first Nyquist criterion (Nyquist-I), guarantees that a sequence of pulses will not be affected by inter-symbol interference (ISI) if the receiver samples signals at optimum and uniformly spaced instants. In this manuscript the Nyquist-I pulse, called exponential linear pulse (ELP), is evaluated in the time and frequency domain using...
We describe a “crowd measurement” project, referred to as PoQeMoN, whose main objective is to identify Quality of Service (QoS) indicators in order to predict the Quality of Experience (QoE) for HTTP YouTube content on mobile networks. Results are based on experiments on an operational network. The second contribution of this paper is to show that the proposed indicator is easy to implement in order...
In this paper, we present a channel model that characterizes the non-stationarities of small-scale multipleinput multiple-output (MIMO) vehicle-to-vehicle (V2V) double-Rayleigh fading channels that arise from the temporal variations of the propagation delays. The analysis of the correlation properties of the proposed channel model is the main objetive of our paper. To achieve this goal, we derive...
In a MIMO wireless communications system, a space-time block code specifies how the data symbols are transmitted over different antennas at different time instants. A hybrid space-time code attempts to obtain some of the available diversity and multiplexing gains, achieving low error probability and high data rate. The LD StBc-VBLAST hybrid code layers one spatial-multiplexing antenna (to increase...
Although Fog computing specifies a scalable architecture for computation, communication and storage, there is still a demand for better Quality of Service (QoS), especially for agile mobile services. Both industry and academia have been working on novel and efficient mechanisms for QoS provisioning in Fog computing. This paper presents a classification of services according to their QoS requirements...
In this paper, we consider a Device-to-Device (D2D) cellular network in which idle users can work as relays between cell users and the base station to improve their data rate. The relaying induces a cost for the User Equipment Relays (UER), that should be compensated with a payment from the mobile operator so that UERs accept to offer the service. The problem hence arises for the operator to match...
For complex large scale networks, like social networks, it is typically impossible to observe complete information about their topology structure or link weight directly. A recent proposal, the network resonance method, can estimate the eigenvalues and eigenvectors of the Laplacian matrix for representing network structure, by using the resonance phenomena of oscillation dynamics on networks. However,...
A possible scenario for the evolution of Television Broadcast is the adoption of 8 K resolution video broadcasting. To achieve the required bit-rates MIMO technologies are an actual candidate. In this scenario, this paper collected electric field levels from a MIMO experimental system for TV broadcasting to tune the parameters of the ITU-R P.1546 propagation model, which has been employed to model...
Location-aware devices will create new services and applications in emerging fields such as autonomous driving, smart cities, and the Internet of Things. Many existing localization systems rely on anchors such as satellites at known positions which broadcast radio signals. However, such signals may be blocked by obstacles, corrupted by multipath propagation, or provide insufficient localization accuracy...
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