New quasi-TEM waveguides using artificial surfaces and their application to antennas and circuits

Research interest: In recent years we have seen the emergence of commercial applications at high frequencies, such as the top part of the microwave band and the millimeter and sub-millimeter bands, and it is expected a big increase in the coming years. This growing demand requires a rapid development of low-cost technology with good performance at these frequencies, where common technologies, such as microstrip and standard waveguides, have some shortcomings. In particular, existing solutions for high-gain planar scanning antennas at these frequencies su er from the disadvantages of these technologies giving rise to high-cost products not suitable for high volume production. Objectives: The main objective of this thesis is to study the feasibility of a new proposal to improve existing solutions to date for low-cost high-gain planar scanning antennas at high frequencies. This overall objective has resulted in another central objective of this thesis, which is the research of new quasi-TEM waveguides that are more appropriate than current technologies for the realization of circuits and components at these frequency bands. These guided solutions make use of periodic or arti cial surfaces in order to con- ne and channel the elds within these waveguides. Methodology: The work follows a logical sequence of speci c tasks aimed at achieving the main objective of this thesis. Chapter 2 presents the proposed guiding solution and shows its performance numerical and experimentally. The optimized design of high-gain antennas based on waveguide slot arrays requires the development of e cient ad-hoc codes. The implementation and validation of this code is presented in Chapter 3, where a new method for the analysis of corrugated surfaces is proposed, and in Chapter 4, which extends this code to the analysis of waveguide slot arrays. The process design and optimization of a two-dimensional array is described in Chapter 5, where a preliminary experimental validation is also described. Moreover, the proposed guiding solution has inspired the development of a new guiding technology of wider bandwidth and more versatile for the realization of circuits and components at high frequencies. Chapter 6 presents the contributions to the study of this technology and its application to the design of circuits.Alfonso Alós, E. (2011). New quasi-TEM waveguides using artificial surfaces and their application to antennas and circuits [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11073Palanci

La mentoría en la Escuela Universitaria Politécnica de la Universidad de Sevilla

XVIII Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas. Escuela Técnica Superior de Ingenieros Industriales y de Telecomunicación. Universidad de Cantabria : Santander, 6 a 9 de julio de 2010Con el fin de integrar a los alumnos de nuevo ingreso, la Escuela Universitaria Politécnica de la Universidad de Sevilla ha puesto en marcha en el curso 2008-09 un Plan de Acción Tutorial (EUPAT) basado en una red en la que participan el profesorado tutor, alumnado mentor y alumnado tutorizado. En el presente trabajo se resumirá el proceso de formación del alumnado mentor y el trabajo desarrollado por el mismo dentro del Plan de Acción Tutorial. Así mismo, se analizarán las dificultades encontradas durante el transcurso de su formación y realización de la labor de mentoría y el nivel de satisfacción alcanzado. Finalmente, se hará una reflexión sobre las debilidades y los puntos de mejora que se pueden deducir del desarrollo hasta el momento de esta acción tutorialIn order to integrate new students, the Polytechnic School of the University of Seville has launched in the year 2008-09 an Tutorial Action Plan (EUPAT) based on a network involving teachers, mentor students and tutored students. In this paper we resume the formation of mentor students and work developed by the same within the Tutorial Action Plan. Also, analyzing the difficulties encountered during the course of their training and carrying out the work of mentoring and the satisfaction level achieved. Finally, we will reflect on the weaknesses and areas for improvement that can be deducted from the development until the time of this action tutorial

Protagonismo del mentor en una actividad tutorial de carácter multidisciplinar en Ingeniería

XIX Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas : Barcelona, 6 a 8 de julio de 2011En la Escuela Politécnica Superior (EPS) de la Universidad de Sevilla se ha trabajado, por tercer curso consecutivo, en un Plan de Acción Tutorial desarrollado por 16 profesores tutores y 20 alumnos mentores de 5 titulaciones de Ingeniería Técnica. El objetivo perseguido en este curso ha sido potenciar actividades que han surgido del propio albedrío de los alumnos mentores, lo que ha dado como resultado la realización de una serie de actividades de mentoría motivadas y dirigidas desde el principio por los alumnos mentores. La actividad conjunta de todos ellos ha llevado a organizar unos subgrupos de mentorías en función de determinadas características del alumnado de primer curso (deportistas, trabajadores, becarios de otras universidades…), a realizar reuniones presenciales de mentores para puesta a punto de estas actividades así como de puesta al día de los resultados que se iban consiguiendo, además de organizar una segunda captación de mentorizados tras las notas del primer cuatrimestre, y la protagonización de una Jornada de Mentoría al final del curso.A third edition with 16 tutorial lecturers and 20 tutorial students from five different degrees (Technical Engineering of the Polytechnical School, EPS, at University of Seville) in a Tutorial Plan development, has been prepared. During the present year, the main characteristic has been a serial of mentoring actions motivated and directed by these mentors. This activity has been organized considering several subgroups of mentoring depending on special characteristics in first year students (sportsplayers, workers, grant holders from other universities…), moreover the organization of a second recruiting of new students after the first term marks, updating meetings for mentors only, and to be main figures in a Congress on Mentoring at the end of the academic year

Gap Waveguides using a suspended stripon a bed of nails

This letter discusses the feasibility of a new type of waveguide consisting of a strip suspended on a bed of nails. The bed of nails enforces a stopband, while the strip opens a propagating path that can be used to design circuits and feeding networks for the microwave and millimeter-wave bands. Advantages and drawbacks with respect to existing ridge gap waveguide are discussed. Experimental demonstration is also given. © 2011 IEEE.Manuscript received July 19, 2011; accepted August 17, 2011. Date of publication September 08, 2011; date of current version October 06, 2011. This work was supported in part by the Spanish Ministerio de Ciencia e Innovacion under Projects TEC2010-20841-C04-01 and CSD2008-00068.Valero-Nogueira, A.; Baquero Escudero, M.; Herranz Herruzo, JI.; Domenech Navarro, J.; Alfonso Alós, E.; Vila Jiménez, A. (2011). Gap Waveguides using a suspended stripon a bed of nails. IEEE Antennas and Wireless Propagation Letters. 10(1):1006-1009. doi:10.1109/LAWP.2011.2167591S1006100910