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In this work, we present an acoustic modem system that transmits data using multicarrier modulation through the air interface. The choice for this type of modulation over single carrier modulation arises from the need for an efficient use of the limited bandwidth, the minimization of multipath effects as frequency fading. The system transmits data using sound waves resting on the output and input...
We compare three clipping techniques for reducing the PAPR of an UFMC signal over an AWGN channel. First, the techniques are analyzed probabilistically showing that deep clipping reduces the most, but it also has the worst performance. Then, the percentile levels of deep factor and level clipping are optimized, achieving similar performance that common techniques.
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...
Minimum mean square error (MMSE) linear detector has been considered as one of the potential detection algorithm for uplink multi-user massive MIMO systems, because it can achieve the near-optimal bit error rate (BER) performance. However, it involves matrix inversion with high complexity. Thus, the conventional Gauss-Seidel (GS) method has been applied for obtain a low-complexity MMSE detector without...
In this paper, we have proposed a novel passive ultra high frequency (UHF) radio frequency identification (RFID) metal tag antenna mountable on the metallic surface to resonate at 930 MHz. The techniques with double slits for impedance matching and reading distance enhancement is used to obtain a good performance. All simulations are carried out by Ansoft HFSS software and Intermec read verifies the...
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, self-interference (SI) cancellation algorithm based on Space Projection Algorithm (SPA) is proposed for Full-Duplex (FD) Multiple-Input Multiple-Output (MIMO) relays in an indoor wireless communication system. The simultaneous transmission and reception of the same radio signal imply a SI around the relay transceiver. The principal challenge of implementing the FD-MIMO relay is to this...
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...
In massive multiple-input multiple-output (MIMO) systems, with the increase of the number of received antennas at base station (BS), the linear detectors, as minimum mean-square error (MMSE), are able to achieve the near-optimal performance. However, these detectors involve matrix inversion with high complexity. Thus, in order to reduce the complexity, Neumann Series (NS) expansion has been proposed...
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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