Tesis doctoral de Esperanza Alfonso Alos
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 suffer 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 artificial surfaces in order to confine and channel the fields within these waveguides. methodology: the work follows a logical sequence of specific 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 efficient 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. results: it has been shown numerical and experimentally that the two guiding structures, which have been studied here, one designed to support a slot array, and the other one especially interesting for the realization of circuits and components, have particular characteristics that give them great potential for application in antennas and circuits at high frequencies. The feasibility study culminates with the design of a two-dimensional slot array fed by the proposed guide. For this design an efficient ad-hoc code based on a new method for the analysis of corrugated surfaces has been used. this numerical implementation is one of the main contributions of this work. The application of the second guiding structure to the realization of circuits has been demonstrated through the design, fabrication and measurement of some microwave circuits.
Datos académicos de la tesis doctoral «New quasi-tem waveguides using artificial surfaces and their application to antennas and circuits«
- Título de la tesis: New quasi-tem waveguides using artificial surfaces and their application to antennas and circuits
- Autor: Esperanza Alfonso Alos
- Universidad: Politécnica de Valencia
- Fecha de lectura de la tesis: 16/06/2011
Dirección y tribunal
- Director de la tesis
- Alejandro Valero Nogueira
- Tribunal
- Presidente del tribunal: María no Baquero escudero
- per-simon Kildal (vocal)
- zvonimir Sipus (vocal)
- eva Rajo iglesias (vocal)