Search results for "Communications system"
showing 10 items of 78 documents
‘Communication breakdown’: the evolution of signal unreliability and deception
2014
For a signalling system to be stable, signals must confer net fitness benefits to senders and receivers, which means that some aspect of their design must correlate with a quality that receivers benefit from knowing about. However, examples abound where this correlation is complicated by phenomena commonly referred to as deception and/or signal unreliability. We argue here that unreliability and deception are notions marred with conceptual ambiguities, often used as equivalent or as catch-all terms for qualitatively different processes. Signal unreliability refers to a pattern of design–information dissociation that can arise through different processes, some deceptive and some not, with di…
Survey of Cyber Threats in Air Traffic Control and Aircraft Communications Systems
2018
Air traffic control systems based on the ADS-B standard have been widely adopted in civil aviation to the point that they are now considered the de facto standard. ADS-B provides major benefits to airports and airlines by increasing the safety of air traffic management and control and allowing more flights to travel near busy airports. However, the ADS-B technology lacks sufficient security measures. The ADS-B system is vulnerable and exposed to cyberattacks. We survey the potential known threats and attacks against ADS-B and assess the potential cybersecurity threats to air traffic management and control. The widespread use of ADS-B and the lack of security features in it, i.e., all the AD…
A webGIS-based system for real time shelf life prediction
2016
Technologies to acquire and monitor changes in the product shelf life were described.Four different SL predictive models were considered.A simulated transport using a prototype of Smart Logistic Unit was analysed.Real time shelf life prediction system was implemented in a webGIS platform. Shelf-life (SL) prediction and Least Shelf-life First Out (LSFO) stock strategy are important factors in perishable food supply chain in order to reduce quality and economic losses.In particular, distribution represents one of the main critical phases in logistic chain management and only the introduction of monitoring procedure can allow a reduction in food losses. Literature shows several mathematical mo…
A Geometrical Three-Ring-Based Model for MIMO Mobile-to-Mobile Fading Channels in Cooperative Networks
2011
Published version of an article published in the journal: Eurasip Journal on Advances in Signal Processing. Also available from the publisher at: http://dx.doi.org/10.1155/2011/892871. OA This paper deals with the modeling and analysis of narrowband multiple-input multiple-output (MIMO) mobile-to-mobile (M2M) fading channels in relay-based cooperative networks. In the transmission links from the source mobile station to the destination mobile station via the mobile relay, non-line-of-sight (NLOS) propagation conditions are taken into account. A stochastic narrowband MIMO M2M reference channel model is derived from the geometrical three-ring scattering model, where it is assumed that an infi…
A simulation model for wideband MIMO vehicle-to-vehicle fading channels in T-junction propagation environments
2010
In this paper, we propose a high-performance simulation model for wideband multiple-input multiple-output (MIMO) vehicle-to-vehicle (V2V) fading channels in T-junction propagation environments. The so-called Riemann sum method (RSM) is applied for the parametrisation of the simulation model. Furthermore, the statistical properties of the wideband MIMO V2V channel simulation model, such as the space-time-frequency cross-correlation function (STF-CCF), the two-dimensional spatial cross-correlation function (2D spatial CCF) and the temporal auto-correlation function (ACF) are studied. Finally, the high accuracy of the proposed simulation model is demonstrated by comparing the correlation prope…
Middleware with QoS Support to Control Intelligent Systems
2008
This paper presents the architecture of a middleware for control component-based distributed systems. The fundamental idea underlying this architecture is the use of a hierarchical communications structure called "logical namespace tree" and a structured set of control processes interconnected, called "logical sensors graph". This architecture is named frame sensor adapter control (FSA-Ctrl). The aim of FSA-Ctrl is to provide a simple interface to specify the control actions and ensure a communication with some specified QoS parameters restrictions. In this architecture both systems, communication and control, manages the QoS policies. The communication system is based on the data distribut…
A Bacterial-Based Algorithm to Simulate Complex Adaptative Systems
2014
Paper presented at the 13th International Conference on Simulation of Adaptive Behavior which took place at Castellón, Spain in 2014, July 22-25. Bacteria have demonstrated an amazing capacity to overcome envi-ronmental changes by collective adaptation through genetic exchanges. Using a distributed communication system and sharing individual strategies, bacteria propagate mutations as innovations that allow them to survive in different envi-ronments. In this paper we present an agent-based model which is inspired by bacterial conjugation of DNA plasmids. In our approach, agents with bounded rationality interact in a common environment guided by local rules, leading to Complex Adaptive Syste…
Power-Line Communication in Medium-Voltage System: Simulation Model and Onfield Experimental Tests
2012
The aim of this paper is to develop a complete model of a power-line communication (PLC) system operating on a medium-voltage (MV) network. The core-shield configuration was chosen for signal transmission in the power cables. In order to validate the developed model experimental, the medium-voltage network of the Favignana island was used to carry out detailed testing. The transmission was performed between two transformer substations in the presence of mains voltage (i.e., 24 kV). ST7540 FSK power-line transceivers, together with capacitive coupling interfaces, were used for the transmission and the reception of the communication signal. The correlation between the experimental measurement…
On the spectral moments of non-WSSUS mobile-to mobile double-Rayleigh fading channels
2017
This paper deals with the mathematical analysis of the spectral moments of non-wide-sensestationary uncorrelated-scattering (non-WSSUS) mobile-to-mobile (M2M) double-Rayleigh fading channels. The point of departure is a recently proposed geometry-based statistical model (GBSM) for M2M double-Rayleigh fading channels from which general analytical expressions are derived for the average Doppler shift, Doppler spread, average delay, and delay spread. Closed-form solutions of such expressions are presented for the particular case of the geometrical two-rings scattering model. The obtained results indicate that the average Doppler shift and Doppler spread are directly influenced by not only the …
An RF-Based Positioning Method for Tracing a Cluster of Moving Scatterers in Non-Stationary Indoor Environments
2021
Author's accepted manuscript © 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. This letter presents a novel iterative positioning method for tracing the body segments of a person moving indoors using radio-frequency (RF) signals. The indoor space is equipped with a multiple-input multiple-output (MIMO) communication system. The person is modelled by a cluster of …