Now showing items 1-10 of 27
Dual channel bidirectional wavelength division multiplexing datalink
(Virginia Tech, 1988-06-05)
Wavelength division multiplexing two channels on one fiber is one approach that enables us to make use of the extremely large bandwidth of optical fibers. We start with an analysis of optical fibers, sources, detectors, ...
Synthesis of Ultra-Wideband Array Antennas
(Virginia Tech, 2014-01-20)
Acquisition of ultra-wideband signals by means of array antennas requires essentially frequency-independent radiation characteristics over the entire bandwidth of the signal in order to avoid distortions. Factors contributing ...
Designs for Zero Polarization-Mode Dispersion And Polarization-Maintaining Fibers
(Virginia Tech, 1998-05-08)
This dissertation addresses several aspects pertaining to polarization in optical fibers and optical waveguide devices. In particular, the analysis and design of fibers that maintain polarization over long lengths, ...
A Generalized Analysis of Multiple-Clad Fibers with Arbitrary Step-Indx Profiles and Applications
(Virginia Tech, 1997-04-22)
A generalized analysis of multiple-clad cylindrical dielectric structures with step-index profiles is presented. This analysis yields unified expressions for fields, dispersion equation and cutoff conditions for weakly ...
Log-Periodic Loop Antennas
(Virginia Tech, 1999-07-27)
The Log-Periodic Loop Antenna with Ground Reflector (LPLA-GR) is investigated as a new type of antenna, which provides wide bandwidth, broad beamwidth, and high gain. This antenna has smaller transverse dimensions (by a ...
Low Nonlinearity Optical Fibers for Broadband and Long-Distance Communications
(Virginia Tech, 1998-02-11)
A class of low nonlinearity dispersion-shifted and dispersion-flattened fibers for broadband and long haul applications is presented. The refractive index profiles of these fibers assume a depressed-core multi-clad geometry ...
New Designs for Wideband Hemispherical Helical Antennas
(Virginia Tech, 2008-07-29)
A unique property of spherical and hemispherical helical antennas is that they provide very broad half-power beamwdiths and circular polarization over a narrow bandwidth. In this thesis, new designs for hemispherical helical ...
Multifilar Hemispherical Helical Antennas
(Virginia Tech, 2003-10-31)
Helices are broadband antennas that provide moderate gain, largely real input impedance and circular polarization when operating in the axial mode regime. A modified form of the helix, the spherical helix, has been shown ...
Coupled-waveguide Fabry-Perot resonator
(Virginia Tech, 1992-12-04)
Investigation of High-Nonlinearity Glass Fibers for Potential Applications in Ultrafast Nonlinear Fiber Devices
(Virginia Tech, 2005-07-28)
Nonlinear fiber devices have been attracting considerable attention in recent years, due to their inherent ultrafast response time and potential applications in optical communication systems. They usually require long ...