A Study on Secret Key Rate in Wideband Rice Channel

Standard cryptography is expected to poorly fit IoT applications and services, as IoT devices can hardly cope with the computational complexity often required to run encryption algorithms. In this framework, physical layer security is often claimed as an effective solution to enforce secrecy in IoT systems. It relies on wireless channel characteristics to provide a mechanism for secure communications, with or even without cryptography. Among the different possibilities, an interesting solution aims at exploiting the random-like nature of the wireless channel to let the legitimate users agree on a secret key, simultaneously limiting the eavesdropping threat thanks to the spatial decorrelation properties of the wireless channel. The actual reliability of the channel-based key generation process depends on several parameters, as the actual correlation between the channel samples gathered by the users and the noise always affecting the wireless communications. The sensitivity of the key generation process can be expressed by the secrecy key rate, which represents the maximum number of secret bits that can be achieved from each channel observation. In this work, the secrecy key rate value is computed by means of simulations carried out under different working conditions in order to investigate the impact of major channel parameters on the SKR values. In contrast to previous works, the secrecy key rate is computed under a line-of-sight wireless channel and considering different correlation levels between the legitimate users and the eavesdropper

Toward Ubiquitous Real-Time Radio Propagation Modeling: The Exploitation of Cyber Resources, GPU and Fast and Accurate EM Algorithms

Radio propagation modeling and prediction play an important role in the understanding of electromagnetic (EM) wave propagation in complex environments, as well as in the design of wireless communications and radar systems

Tecnologie ad Agenti per Piattaforme di Gaming: un caso di studio basato su JaCaMo e Unity

Progettazione di un middleware che permetta la comunicazione tra piattaforme ad agenti e piattaforme di gaming. Unity3D e JaCaMo sono stati utilizzati come caso di studio

Strategies and Alliances into Action to Improve National Collaboration

The Italian NILDE network of libraries continues to grow through the use of the NILDE system and currently comprises more than 600 Italian librarians and about 10.000 registered end-users.The system allows to daily manage and to record all the Inter-Library-Loan (ILL) operations, with a high national coverage. This paper presents the NILDE network governance and evolution and the strategies that have been put into action to improve collaboration in resource sharing among the participants. These strategies include: − release of best practices and worst practices; − activities to promote the knowledge about the network; − cooperation with the Italian national catalogs and consortia; − data analysis about ILL and its performance, related to: turn around time, reciprocity factor, requested/supplied documents imbalance analysis, analysis of ILL requested serial titles and their relationship with consortial e-only acquisitions. The availability of such a high volume of ILL data has allowed for the first time to analyze the trends and gaps of ILL and to help future cooperative acquisitions planning

Fast-Fading Modeling in Wireless Industrial Communications

Wireless channel properties in industrial environments are significantly impacted by heavy machinery, leading to complex multipath propagation and strong blockage effects. Conventional empirical models employed in factory settings are constrained by their limited flexibility and applicability to diverse industrial conditions. In this study, this limitation is tackled in a twofold way. First, machine learning algorithms, including linear regression and a Multi-Layer Perceptron, are employed to capture the complex relationships between fast-fading effects and key features of the industrial layout. Second, a flexible empirical formula is proposed to model fast-fading phenomena with enhanced adaptability, providing a comprehensive solution for diverse industrial contexts. The results align with previous studies and provide some trends in fast-fading sensitivity to different industrial features. The machine learning model demonstrates superior accuracy compared to the empirical formula, which nevertheless still achieves reasonable performance despite its simplicity

Frequency Diverse Array for Signal Geofencing in Wireless Communications: Does It Work ?

Frequency Diverse Array is an advanced antenna technology for clustering received power spatial distribution in specific areas, which has shown significant potential in many applications, including radar or wireless power transfer. In wireless communications, signal geofencing might be beneficial in increasing communication secrecy or reduce interference issues, but system communications through frequency diverse arrays require careful consideration about several design parameters. In this paper, a detailed analysis of the sensitivity of the geofencing effectiveness to the main array parameters is carried out. The analysis covers many aspects of the design, including the selection of the geometrical layout and the number of elements of the array, the frequency increase policy and the frequency offset across the elements and their spacing. The study also discusses the trade-offs between different design choices and provides insights into the performance in terms of focus efficiency and size of the focus area. Results show that bidimensional layouts, e.g. circular or planar, often represent effective solutions, whereas the linear arrangement can be a viable option only in case the frequencies are spread across the elements in a random-like fashion. Frequencies are usually increased according to either a logarithmic or a linear policy. The linear solution in general yields lower performance, but also lower complexity. Frequency offset, number of elements and their spacing represent further project parameters. Finally, a preliminary assessment of the multipath effect on the focus task shows that the performance of frequency diverse arrays can be affected by complex propagation conditions and deserve further investigations

La historiografía liberal de Miguel Luis Amunátegui

This article establish the influence of the liberal ideology in the works of Chilean historian Miguel L. Amunátegui, which was strongly conditioned by the political contingency (half-full of century XIX). Thus, it understands the Colony like a dark time (blaming to Catholic Church), and he characterizes O'Higgins government like a oppressive dictatorship. Of both ways it opposed the predominance of the authoritarian government of his time. Also, the article analyzes reception that Amunategui's work have generated in the national historiography, which reveals the different political tendencies from the Chilean historians.Este artículo establece la influencia de la ideología liberal en la obra del historiador chileno Miguel L. Amunátegui, la cual estuvo fuertemente condicionada por la contingencia política (mediados del siglo XIX). Así, comprende la Colonia como una época oscura (culpando a la Iglesia), y caracteriza el gobierno de O'Higgins como una opresiva dictadura. De ambos modos impugnaba el predominio de los gobiernos conservadores y autoritarios de su contemporaneidad. Se analiza además la recepción que su obra ha generado en la historiografía nacional, la cual revela las distintas posiciones políticas de los historiadores chilenos

Interleaved-MIMO DAS for Indoor Radio Coverage: Guidelines for Planning

The combination of distributed antenna systems (DAS) and multiple input multiple output (MIMO) schemes opens the way to a variety of coverage solutions for indoor environment. In this paperinterleaved-MIMO (i-MIMO) DASindoor coverage extension strategies are studied. Their performance in high-order MIMO cases is investigated in realistic conditions through LTE-A link-level simulations, based on statistical data extracted from radio channel measurements; the impact of the deployment strategy on performance is then evaluated and useful planning guidelines are derived to determine the optimum deployment for a given propagation environment