Micromachined Microwave Filters
By: by Ignacio Llamas Garro.
Publisher: University of Birmingham
Published: 2003
Place of publication: Birmingham UK
Language: eng
Copyright date: April 2003
Subjects: Microwave Engineering
Description: Microwave circuits in the millimetre wave region demand low loss, and low
dispersion transmission lines. The work carried out in this thesis is on low loss transmission
lines and filters, based on a square coaxial transmission line which is made only of metal,
avoiding dielectric and radiation losses. The metal structure inside the square coaxial
transmission line is supported by stubs, which provide the mechanical support for the centre
conductor for the coaxial transmission lines and filters.

The coaxial structure is made by stacking thick planar layers of material to suit
microfabrication, providing the means to design high Q Microwave and RF passive devices,
this transmission line structure is compact compared with a microstrip or a stripline, and gives
better loss performance.

Through this thesis, the way of optimising the square coaxial transmission line to
provide a low loss will be presented, which will end in the presentation of one dielectric
supported coaxial structure and three self supported filters, three of them were designed for
the X-band, and one of them was designed for the Ka band. The application of the coaxial
transmission line is demonstrated with wideband and narrow band designs.
Notes: Thesis (PhD) - University of Birmingham UK, School of Engineering, Department of Electronic, Electrical and Computer Engineering.
Table of contents: value: CHAPTER ONE: INTRODUCTION 14; value: CHAPTER TWO: LITERATURE REVIEW 21; value: CHAPTER THREE: TRANSMISSION LINE THEORY 52; value: CHAPTER FOUR: MICROWAVE RESONATORS 78; value: CHAPTER FIVE: GENERAL FILTER DESIGN 102; value: CHAPTER SIX: MICROMACHINED TRANSMISSION LINES AND RESONATORS 126; value: CHAPTER SEVEN: SQUARE COAXIAL MICROWAVE BANDPASS FILTERS 145; value: CHAPTER EIGHT: CONCLUSIONS AND FURTHER WORK 191; value: APENDIX: LIST OF PUBLICATIONS 197