RF-MEMS based passive components and integration concepts for adaptive millimetre wave front-ends
FacultiesFakultät für Ingenieurwissenschaften und Informatik
LicenseStandard (Fassung vom 01.10.2008)
The thesis is dedicated to RF-MEMS based components for fixed and adaptive millimetre-wave front-ends. It is focused on the realisation of components forming the "passive front-end" of RF-systems. This includes the antennas, the phase shifters, and the filters, but excludes all the active circuitry, such as the power amplifiers and mixers. Further, beyond the design of individual components, a large part of the work is concerned about the way the various circuits can be integrated at component level, but also at system level. Aside a first chapter providing an overview of the experimental techniques employed in the work, two kinds of components are principally addressed: the fixed and frequency-agile band-pass filters and the electrically steerable antennas. In the second chapter, band-pass filters micro-machined out of silicon are demonstrated. For these filters, a novel architecture is proposed, which makes possible their fabrication with a single low-cost micro-machining process: the KOH-wet etching of silicon. In a later section, an RF-MEMS-based tuning technique is proposed for these filters. Also, the chapter presents Ku-band fixed and tunable band-pass filters on ceramics. These filters are cavity resonator filters made out of LTCC according to the substrate-integrated technique. The chapter ends with an investigation into the temperature dependence of a cavity resonator processed in LTCC, and an actuation-free compensation technique is presented. The third chapter addresses phased array antennas. Three antennas are presented, where two are made electrically steerable by means of RF-MEMS phase shifters. The phase shifters are processed on silicon and they are integrated in a hybrid fashion onto the substrate of the antennas. One of these antennas is designed on LTCC for operation at Ka-band, and it is electrically steerable in the H-plane. For all three antennas also, the integration concepts are presented and the related measurement results are provided.
Subject HeadingsMillimeterwellenschaltung [GND]
Microelectromechanical devices [LCSH]
Millimeter wave devices [LCSH]
Phase shift circuits [LCSH]