Design and performance evaluation of millimeter-wave flat lens antennas for communications, radar and imaging applications

Millimeter-wave systems introduce a set of particular severe requirements from the antenna point of view in order to achieve specific performances. In this sense, high directive antennas are required to overcome the huge extra path loss. Moreover, each particular application introduces additional re...

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Detalles Bibliográficos
Autor: Imbert Villà, Marc
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2016
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/397648
Acceso en línea:http://hdl.handle.net/10803/397648
https://dx.doi.org/10.5821/dissertation-2117-96599
Access Level:acceso abierto
Palabra clave:Dielectric flat lenses
Cylindrically distributed parameters lens
Millimeter-wave antennas
Automotive radar systems
Beam-steering
Reconfigurable antennas
Switched-beam array
Passive imaging
Power delay profile (PDP)
Root mean square (RMS)
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació
621.3
Descripción
Sumario:Millimeter-wave systems introduce a set of particular severe requirements from the antenna point of view in order to achieve specific performances. In this sense, high directive antennas are required to overcome the huge extra path loss. Moreover, each particular application introduces additional requirements. For example, in very high throughput (VHT) wireless personal area networks (WPANs) communication systems at 60 GHz band beam-steering antennas are needed to deal with high user random mobility and human-body shadowing characteristic of indoor environments. Similarly, beam-steering capabilities are also needed in automotive radar applications at 79 GHz, since the determination of the exact position of an object is essential for most of the functions realized by the radar sensor. In the same way, beam-scanning, which is still commonly mechanically performed nowadays, is also needed in passive imaging systems at 94 GHz. Finally, from the integration perspective, the antennas must be small, low-profile, light weight and low-cost, in order to be successfully integrated in a commercial millimeter-wave wireless system. For these reasons, many types of antenna structures have been considered to achieve high directivity and beam-steering capabilities for the aforementioned millimeter-wave communication, radar and imaging applications at 60, 79 and 94 GHz. The most part of the currently adopted solutions are based on the expensive, complex and bulky phased-array antena concept. Actually, phased-array antenna systems can scan the beam at a fast rate. However, they require a complex integration of many expensive, lossy and bulky circuits, such as solid-state phase shifters and beam-forming networks. This doctoral thesis has contributed to the study, development, and assessment of the performance of innovative antena solutions in order to improve the existing architectures at millimeter-wave frequencies, conveniently solving the problems related specifically to short-range high data rate communication systems at 60 GHz WPAN band (including future 5G millimeter-wave systems), automotive radar sensors at 79 GHz band, and communications, radar, and imaging systems at 94 GHz. The specific goals pursued in this work, focused on defining an alternative antenna architecture able to achieve a full reconfigurable 2-D beam-scanning of high gain radiation beams at millimeter-wave frequencies, has been fulfilled. In this sense, this thesis has been mainly devoted to study in depth and practically develop the fundamental part of an innovative switched-beam antenna array concept: novel inhomogeneous gradient-index dielectric flat lenses, which, despite their planar antenna profile configurations, allow full 2-D beam-scanning of high gain radiation beams. A transversal study, going from theoretical investigations, passing by numerical analysis, new fabrication strategies, performance evaluation, and to full experimental assessment of the new antenna architectures in real application environment has been successfully carried out.