A Cavity-Backed Shorted Annular Patch (SAP) Array for Mid-Range V-Band Backhauling Applications

This paper presents a new improved gain array configuration well suited for mid-range V-band backhauling applications. The proposed solution is based on a cavity-backed shorted annular patch (SAP) antenna loaded with a parasitic patch element for gain maximization. This solution is proved by designing and measuring a 4 × 4 array which presents a reflection coefficient bandwidth covering the frequencies from 58.7 to 63.25 GHz (7.6% at 60 GHz). The experimentally validated array gain is equal to 18 dBi corresponding to 37.9% of aperture efficiency. The antenna and array configurations presented in this paper are optimized to minimize the manufacturing cost and complexity. This result is achieved through a novel beamforming network (BFN) configuration, implemented using a dual-layer substrate-integrated waveguide (SIW) technology, and partly integrated on the array aperture. The achieved results demonstrate how the performance of the cavity backed SAP array is comparable to the ones achieved with more complex and expensive solutions

ANALYSIS OF LOSSY SIW STRUCTURES BASED ON THE PARALLEL PLATES WAVEGUIDE GREEN'S FUNCTION

Abstract—In this paper, a full-wave analysis technique of lossy substrate integrated waveguides, based on the dyadic Green’s function of the parallel plate waveguide, is presented. The field inside the waveguide is expressed in terms of cylindrical vector wave-functions and the finite conductivity of the top and of the bottom plates, and of the metallic vias are taken into account. Losses into the dielectric substrate are also included. Coaxial ports are considered as sources and self and mutual admittances are evaluated. Cases of practical structure taken from literature are presented showing a very good agreement with the most used commercial software. 1

A Gain Levelling Technique for On-Chip Antennas Based on Split-Ring Resonators

This paper introduces a gain enhancement technique for monolithically integrated antennas. Such devices can suffer from gain dips within their operating bandwidth due to standing waves arising in the die or caused by interactions with other on-chip components. In this work, it is shown how these effects can be significantly mitigated by parasitically coupling square Split Ring Resonators (SRR) to the fed antenna. The SRRs geometry and their coupling with the master antenna can be set in such a way that they create an additional resonance that cancels gain drops and improves impedance matching. The proposed configuration has been validated using a W-band monopole antenna in a standard $0.13~\mu \text{m}$ SiGe BiCMOS process. Thanks to the proposed approach, it was possible to compensate a gain drop of about 7 dB at about 85 GHz. As a result, the experimental assessment showed a maximum measured antenna gain of 1.61 dB at 81.5 GHz and an operating bandwidth from 77 to 87 GHz

Estudio jurisprudencial sobre el derecho al trabajo de los vendedores ambulantes en Bogotá

Artículo de ReflexiónEl presente artículo de investigación presenta el resultado de la realización de una revisión jurisprudencial en torno a los pronunciamientos de las Altas Cortes acerca del derecho al trabajo de los vendedores ambulantes, su importancia se enmarca en la vulneración constante que se ha ido presentando frente al derecho de los vendedores ambulantes y en el conflicto que se da entre este derecho y el derecho que tienen los ciudadanos en general a disfrutar del espacio público.INTRODUCCIÓN 1. DESARROLLO JURISPRUDENCIAL 2. CONSIDERACIONES DEL AUTOR 3. CONCLUSIONES 4. REFERENCIASPregradoAbogad

Time, intersubjectivity, and musical relationship in Alfred Schutz

In questo lavoro, affronto alcuni aspetti della relazione tra tempo e intersoggettività in Alfred Schutz . Presento una sintesi dell’architettura metodologica del sociologo austriaco, delineando la specificità della relazione tra tempo e coscienza. Prendo in esame la trattazione dell’esperienza musicale come esempio di declinazione peculiare di una serie di dinamiche temporali connesse alla costituzione intersoggettiva dei significati. Infine, espongo alcune tesi di autori che si sono occupati della relazione tra tempo, intersoggettività e musica in Schutz. La relazione musicale è un esempio di contesto dotato di senso, non oggetto di concettualizzazione, che esemplifica la relazione tra senso soggettivo ed esperienza dell’altro. La teoria dell’appresentazione di Schutz è il centro del processo di costituzione dei significati della prensione dell’altro. L’emersione dei significati è legata alle dinamiche dei poli passivi e attivi della coscienza e alla costituzione, nella we-relation, di una dimensione radicalmente intersoggettiva nella quale si supera la distinzione cartesiana tra interno ed esterno.Time, intersubjectivity, and musical relationship in Alfred Schutz Riccardo Venturini In this work I tackle certain aspects of the relationship between time and intersubjectivity in Alfred Schutz. I present a summary of the methodological architecture of the Austrian sociologist, outlining the specificity of the relationship between time and consciousness. I discuss the treatment of the musical experience as an example of the peculiar declination of a series of temporal dynamics connected to the intersubjective creation of meanings. Finally, I set out some thoughts related to the debate on the relationship between time, intersubjectivity and music in Schutz. The musical relationship is a context endowed with meaning, not the object of conceptualization, that allows us to identify in a paradigmatic way the relationship between the subjective sense and experience of the other. The theory of appresentation of Schutz is the center of the process of constitution of meaning of the understanding of the other. The emergence of meaning is related to the dynamics of the passive and active poles of the consciousness and the constitution, in the we-relation, of a radically intersubjective dimension that exceeds the Cartesian distinction between inside and outside

X/Ka-Band Dual-Polarized Digital Beamforming Synthetic Aperture Radar

This paper presents a digital beamforming (DBF) synthetic aperture radar (SAR) for future spaceborne earth observation systems. The objective of the DBF-SAR system is to achieve a low cost, lightweight, low-power consumption, and dual-band (X/Ka) dual-polarized module for the next-generation spaceborne SAR system in Europe. The architectures and modules of the proposed DBF-SAR system are designed according to a realistic mission scenario, which is compatible with the future small/microsatellites platforms. This system fills an important gap in the conception of the future DBF-SAR, facilitating a high level of integration and complexity reduction. The proposed system is considered not only the first demonstrator of a receive-only spaceborne DBF system, but also the first X/Ka-band dual-polarized SAR system with shared aperture. This paper presents a description of the proposed instrument hardware and first experimental validations. The concept and design of the DBF multistatic SAR system are discussed and presented first, followed by the design of subsystems such as DBF networks, microwave integrated circuit, and antennas. Simulated and measured results of the subsystems are presented, demonstrating that the proposed SAR instrument architecture is well-suited for the future SAR applications

mm-Wave Antennas For Satellite And Mobile Communications

Dottorato di Ricerca in Information and Communication Engineering For Pervasive Intelligent Environments, Ciclo XXIXEver growing demands for higher data rate and bandwidth are pushing wireless applications to millimetre-wave band (3-300GHz), where sufficient bandwidth is available and high performance can be achieved without using complex modulation systems. In addition to Telecom applications, millimetre-wave bands has enabled novel short range and long range radar sensors for automotive as well as high resolution imaging systems for medical and security. The major obstacle for the wide deployment of commercial wireless and radar systems in this frequency range is the high cost of the overall system. The main object of this work is to investigate and to develop different type of antenna that could be applied in satellite communications, in the future fifth generation of mobile networks and on radar automotive systems. In particular, in the present thesis, four antennas have been developed. A dual band dual polarized antenna array for Satcom-On-The-Move application that gives the possibility to obtain a fixed beam on the frequency range 19-21GHz (Rx band) and 29-31GHz (Tx band). This structure could be used in association with a fully mechanical pointing system. A Reflector terminal in the Q/V bands that could be use on the backhaul point of the 5G future architecture. A Ka band scaled version of the antenna has been realized and measured proving that it can be a valid solution for compact earth terminals. A novel reflectarray with potential applications in both satellite communications and high speed point-to-point radio links. Finally, a 77GHz transmit-array antenna mounted on a QFN package. This kind structure, due to the compact dimensions, could be represent a possible solution for automotive radar systemUniversità della Calabri