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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Analysis and Design of W-Band Phase Shifters

Sarkas, Ioannis 28 July 2010 (has links)
This thesis describes 80−94GHz and 70−77GHz interpolating phase shifters and the corresponding transmitter and receiver ICs, fabricated in 65-nm CMOS and SiGe BiCMOS technologies, respectively. Lumped inductors and transformers are employed to realize small-form factor 90 degree hybrids as needed in high density phased arrays. The CMOS transmitter exhibits absolute phase and amplitude errors of 4 degrees and 4dB, respectively, at 90GHz, when the phase is varied from 0 degrees to 360 degrees in steps of 22.5 degrees. The absolute phase error in the SiGe BiCMOS receiver is less than 5 degrees, with a maximum gain imbalance below 3dB at 74GHz. The peak gain and power consumption are 3.8dB and 142mW from 1.2V supply for the CMOS transmitter, and 17dB and 128mW from 1.5V and 2.5V supplies for the SiGe BiCMOS receiver.
2

Analysis and Design of W-Band Phase Shifters

Sarkas, Ioannis 28 July 2010 (has links)
This thesis describes 80−94GHz and 70−77GHz interpolating phase shifters and the corresponding transmitter and receiver ICs, fabricated in 65-nm CMOS and SiGe BiCMOS technologies, respectively. Lumped inductors and transformers are employed to realize small-form factor 90 degree hybrids as needed in high density phased arrays. The CMOS transmitter exhibits absolute phase and amplitude errors of 4 degrees and 4dB, respectively, at 90GHz, when the phase is varied from 0 degrees to 360 degrees in steps of 22.5 degrees. The absolute phase error in the SiGe BiCMOS receiver is less than 5 degrees, with a maximum gain imbalance below 3dB at 74GHz. The peak gain and power consumption are 3.8dB and 142mW from 1.2V supply for the CMOS transmitter, and 17dB and 128mW from 1.5V and 2.5V supplies for the SiGe BiCMOS receiver.
3

Low-cost microstrip line-based ferrite phase shifter

Hui, William W. G January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 73). / xii, 73 leaves, bound ill. (some col.) 29 cm
4

Tuning of electrical properties in InAlN/GaN HFETs and Ba0.5Sr0.5TiO3/YIG phase shifters

Leach, Jacob H., January 1900 (has links)
Thesis (Ph.D.)--Virginia Commonwealth University, 2010. / Prepared for: Dept. of Electrical Engineering. Title from title-page of electronic thesis. Bibliography: leaves 177-185.
5

Magnetic control of superconducting phase-shifters with experimental verification

Troxler, Robert Ernest 12 1900 (has links)
No description available.
6

Generalized inverse lithography methods for phase-shifting mask design

Ma, Xu. January 2007 (has links)
Thesis (M.E.E.)--University of Delaware, 2007. / Principal faculty advisor: Gonzalo Arce, Dept. of Electrical and Computer Engineering. Includes bibliographical references.
7

Integrated MEMS-Based Phase Shifters

Al-Dahleh, Reena January 2008 (has links)
Multilayer microwave circuit processing technology is essential in developing more compact radio frequency (RF) electronically scanned arrays (ESAs) for next generation radar systems. ESAs are typically realized using the hybrid connection of four discrete components: RF manifold, phase shifters or Butler matrices, antennas and T/R modules. The hybrid connection of these components increases the system size, packaging cost and introduces parasitic effects that lead to higher losses. In order to eliminate these drawbacks, there is a need to integrate these components on the same substrate, forming a monolithic phased array. RF MEMS technology enables the monolithic integration of the ESA components into one highly integrated multifunctional module, thereby enhancing ESA designs by significantly reducing size, fabrication cost and interconnection losses. A novel capacitive dual-warped beam shunt MEMS switch is presented that utilizes warped beams to enhance its RF performance. This switch exhibits an off-to-on capacitive ratio of almost 170, isolation better than 40dB, switching speeds as low as 6μs without the need for thin dielectrics or high dielectric constant materials. These MEMS switches are implemented into single pole three throw (SP3T) and single pole four throw (SP4T) configurations. A novel 3-bit finite ground coplanar waveguide switched delay line MEMS phase shifter is developed with four cascaded SP3T dual-warped beam capacitive switches to achieve low-loss performance and simplify ESA design. The fabricated prototype unit exhibits an insertion loss of 2.5∓0.2dB with a phase error of ∓6°. Moreover, a compact 4 x 4 Butler matrix switchable with the use of a MEMS SP4T switch is investigated as an alternative passive beamforming method. The overall beam-switching network is monolithically integrated within a real-estate area of 0.49cm2. This technique provides a unique approach to fabricate the entire beamforming network monolithically. An 8-mask fabrication process is developed that monolithically integrates the MEMS phase shifter and RF combining network on one substrate. The wafer-scale integrated ESA prototype unit has an area of 2.2cm2. It serves as the basic building block to construct larger scanning array modules and introduces a new level of functionality previously achieved only by the use of larger, heavier and expensive systems
8

Integrated MEMS-Based Phase Shifters

Al-Dahleh, Reena January 2008 (has links)
Multilayer microwave circuit processing technology is essential in developing more compact radio frequency (RF) electronically scanned arrays (ESAs) for next generation radar systems. ESAs are typically realized using the hybrid connection of four discrete components: RF manifold, phase shifters or Butler matrices, antennas and T/R modules. The hybrid connection of these components increases the system size, packaging cost and introduces parasitic effects that lead to higher losses. In order to eliminate these drawbacks, there is a need to integrate these components on the same substrate, forming a monolithic phased array. RF MEMS technology enables the monolithic integration of the ESA components into one highly integrated multifunctional module, thereby enhancing ESA designs by significantly reducing size, fabrication cost and interconnection losses. A novel capacitive dual-warped beam shunt MEMS switch is presented that utilizes warped beams to enhance its RF performance. This switch exhibits an off-to-on capacitive ratio of almost 170, isolation better than 40dB, switching speeds as low as 6μs without the need for thin dielectrics or high dielectric constant materials. These MEMS switches are implemented into single pole three throw (SP3T) and single pole four throw (SP4T) configurations. A novel 3-bit finite ground coplanar waveguide switched delay line MEMS phase shifter is developed with four cascaded SP3T dual-warped beam capacitive switches to achieve low-loss performance and simplify ESA design. The fabricated prototype unit exhibits an insertion loss of 2.5∓0.2dB with a phase error of ∓6°. Moreover, a compact 4 x 4 Butler matrix switchable with the use of a MEMS SP4T switch is investigated as an alternative passive beamforming method. The overall beam-switching network is monolithically integrated within a real-estate area of 0.49cm2. This technique provides a unique approach to fabricate the entire beamforming network monolithically. An 8-mask fabrication process is developed that monolithically integrates the MEMS phase shifter and RF combining network on one substrate. The wafer-scale integrated ESA prototype unit has an area of 2.2cm2. It serves as the basic building block to construct larger scanning array modules and introduces a new level of functionality previously achieved only by the use of larger, heavier and expensive systems
9

Designs of true-time-delay lines and digital phase shifters using composite right/left-handed transmission lines

Zhang, Jun, 张君 January 2012 (has links)
The studies of the designs on true-time-delay lines (TTDLs), n-bit digital phase shifters and wideband switched-line phase shifters using composite right/left-handed transmission-line (CRLH TL) unit cells are presented in this thesis. To simplify these designs, a symmetrical CRLH TL unit cell having equal input and output impedance is proposed. In the design of TDDLs, the symmetrical CRLH TL unit cell with higher time-delay efficiency helps achieve a size reduction of 67.9%, compared with the TTDL designed using right-handed transmission line (RH TL). The symmetrical CRLH TL unit cell is further modified to a compact CRLH TL unit cell to further reduce the size by 58%. For performances comparison, the TTDLs using the compact CRLH TL unit cells, symmetrical CRLH TL unit cells and RH TL are studied using computer simulation and measurement. Results show that the TTDLs using the compact CRLH TL unit cells can achieve much longer time delays. The TTDLs designed using CRLH TL unit cells have narrow bandwidths because CRLH TL unit cells have narrow bandwidths. In this thesis, a wideband unit cell obtained by rotating the CRLH TL unit cell by 900is proposed in the design of TTDLs. Simulation and measurement show that the TTDL using wideband unit cells can achieve a time delay about 3 times and 6 times longer than that of the periodic microstrip line (PML) and RH TL, respectively. A 2-bit, 3-bit and 6-bit phase shifters using symmetrical CRLH TL unit cells are designed using computer simulation. In these designs, positive-intrinsic-negative (PIN) diodes mounted on the fingers of the CRLH TL unit cells are used as switches to control the phase response at the output. Different phase shifts are achieved using different switching states determined by controlling bits. The phase shifters are fabricated and measured. Simulated and measured results agree very well. Power-handling capability is also analyzed using surface-current density on the CRLH TL unit cells. Results show that the phase shifters have much higher power-handling capabilities than that of the PIN diodes. A wideband 1800-switched-line phase shifter using symmetrical CRLH TL unit cell is proposed. The switched-line phase shifter employs a symmetrical CRLH TL unit cell as the reference arm and a RH TL as the delay arm to produce a constant phase shift across a wide frequency band. For comparison, a traditional 1800-switched-line phase shifter using RH TLs for both reference and delay arms is also designed. To reduce the size, the CRLH TL unit cell is realized using lump elements (LEs). Wideband 900-and 1800-switched-line phase shifters using LE-CRLH TL unit cells are studied and compared with the traditional 900-and 1800-switched-line phase shifters. Simulated and measured results show that the proposed designs using symmetrical CRLH TL unit cells and LE-CRLH TL unit cells have very constant phase shifts with smaller variations compared with the traditional designs. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
10

RF variable phase shifters for multiple smart antenna transceivers /

Zarei, Hossein. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 135-143).

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