Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Farrokh Ayazi; Committee Member: James D. Meindl; Committee Member: Joy Laskar; Committee Member: Mark G. Allen; Committee Member: Paul A. Kohl. Part of the SMARTech Electronic Thesis and Dissertation Collection.

No description available.

No description available.

Bibliography: leaves 222-230 / xiv, 230 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1992

Thesis(M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (p.40-41).

Thesis: Elec. E., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 1976 / Bibliography: leaves 255-263. / by Dennis V. Marsicano. / Elec. E. / Elec. E. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science

No description available.

Low cost bandpass filters (less than $100) at microwave frequencies cannot be purchased commercially. However, such filters are essential in the design of RF circuits in communications and radar equipment. Reliable microstrip band pass filters which provide an accurate filter response at microwave frequencies can be easily fabricated with low cost. Equations concerning the design of coupled microstrips and microstrip filters are published in the literature and were implemented in a design procedure for maximally flat microstrip band pass filters. The published equations were theoretical and had not been extensively compared with experimental data. Thus, this work established an enhanced microstrip filter design procedure based on experimental data, for a wide range of frequencies and dielectric substrates. The result of this work is an enhanced design procedure for microstrip band pass filters. The new procedure includes a correction factor for the length of the filter resonators which which controls the center frequency of the filter. This correction factor has been found from the measured responses of over 60 filters, which were designed with two different circuit board materials, three different substrate thicknesses, and frequencies ranging between 0.9 and 6 GHz. The experimentally determined length correction factor decreases the error in center frequency from ±5.9% down to ±L7% of the desired design frequency for a wide range of filter designs. The improved procedure has been implemented in a personal computer (PC) program which calculates all dimensions necessary to fabricate microstrip band pass filters in the low microwave frequency range. The maximally flat response obtained is accurate and requires very little tuning. Low cost microstrip band pass filters can now be designed and fabricated easily and with greater accuracy at microwave frequencies. This thesis describes the development of the enhanced design procedure and the results of the filters designed with the new procedure. / Master of Science

This dissertation reports, for the first time, on the design and implementation of tunable micromachined bandpass filters in the ultra high frequency (UHF) range that are fully integrated on CMOS-grade (resistivity=10-20 ohm.cm) silicon. Filters, which are designed in the Elliptic and coupled-resonator configuration, are electrostatically tuned using tunable microelectromechanical (MEM) capacitors with laterally movable interdigitated fingers. Tunable filters and high-quality factor (Q) integrated passives are made in silver (Ag), which has the highest conductivity of all materials in nature, to reduce the ohmic loss. The loss of the silicon substrate is eliminated by using micromachining techniques. The combination of the highest-conductivity metal and a low-loss substrate significantly improves the performance of lumped components at radio frequencies (RF), resulting in an insertion loss of 6 dB for a tunable lumped bandpass filter at 1075 MHz with a 3 dB-bandwidth of 63 MHz and tuning range of 123 MHz. The bandpass filters are encapsulated at the wafer level using a low-temperature, thermally released, polymer packaging process. This thesis details the design, fabrication, and measurement results of the filters and provides strategies to improve their performance. The performance of filter components, including the tunable capacitors and inductors, is characterized and compared to the state-of-the-art micromachined passive components. The silver inductors reported in this thesis exhibit the record high Q, and the silver bandpass filters show the minimum insertion loss that has been achieved on a CMOS-grade silicon substrate, to the best of our knowledge. Alternatively, tunable capacitors can be made in the bulk of silicon using a modified version of the high-aspect-ratio polysilicon and single crystal silicon (HARPSS) fabrication technique to obtain a larger capacitance density at the expense of a higher conductive loss. Using this process, a 15 pF two-port tunable capacitor is fabricated and tuned by 240% with the application of 3.5 V to the isolated actuator. Silver inductors can be post integrated with HARPSS tunable capacitors to obtain tunable filters in the very high frequency (VHF) range. The reported bandpass filters can be monolithically integrated with CMOS and have the potential to replace several transmit and receive acoustic filters currently used in cellular phones.

Graduation date: 1996