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Non redundant spatiotemporal array for time average fourier telescopy applications
Title
Non redundant spatiotemporal array for time average fourier telescopy applications.
Creator
Pava, Diego F., Rhodes, William T., Graduate College
Date Issued
2013-04-12
PURL
http://purl.flvc.org/fcla/dt/3361950
Subject Headings
Fourier transform optics, Optics--Research
Format
Document (PDF)
High-resolution imaging through atmospheric turbulence: Simulation tool development
Title
High-resolution imaging through atmospheric turbulence: Simulation tool development.
Creator
Randunu-Pathirannehelage, Nishantha, Torres Moreno, Yezid, Rhodes, William T., Graduate College
Abstract/Description
We are currently investigating a novel method, known as time-average Fourier telescopy TAFT, for high-resolution imaging through the turbulent atmosphere. This method, which can be applied to long-horizontal-path terrestrial imaging, addresses a need that is not solved by the adaptive optics methods being used in astronomical imaging. Because experimental verification of the method is quite complicated and requiring of considerable instrumentation, we are developing a set of computer...
Show moreWe are currently investigating a novel method, known as time-average Fourier telescopy TAFT, for high-resolution imaging through the turbulent atmosphere. This method, which can be applied to long-horizontal-path terrestrial imaging, addresses a need that is not solved by the adaptive optics methods being used in astronomical imaging. Because experimental verification of the method is quite complicated and requiring of considerable instrumentation, we are developing a set of computer simulation tools that will allow us to establish the validity of the underlying concept and to assess its limitations in ground-level imaging over distances of kilometers to tens of kilometers. The simulation tools, to be described in this poster presentation, allow us to model with high accuracy the passage of light waves through typical ground-level turbulence and for large distances. Preliminary results suggest that, at a minimum, TAFT will allow diffraction-limited imaging with meter-scale optical apertures operating at distances exceeding a kilometer, a capability that improves on that of conventional imaging by orders of magnitude. In this poster we describe the basic scheme of simulation tools, atmospheric turbulence modeling, split-steps Gaussian beam propagation, phase screen modeling, recent progress and remaining challenges.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00005848
Format
Document (PDF)
Fourier telescopy test system
Title
Fourier telescopy test system.
Creator
Randunu-Pathirannehelage, Nishantha, Torres Moreno, Yezid, Rhodes, William T., Graduate College
Date Issued
2013-04-12
PURL
http://purl.flvc.org/fcla/dt/3361948
Subject Headings
Fourier transform optics, Imaging systems, Remote sensing
Format
Document (PDF)
Secure Communication by Coherence Modulation at the Photon Counting Level
Title
Secure Communication by Coherence Modulation at the Photon Counting Level.
Creator
Boughanmi, Abdellatif, Rhodes, William T., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Secure communication is a topic of great importance. The goal of our research reported here is to develop a scheme of secure communication system using coherence modulation at the photon counting level. When operated at the photon counting level, coherence modulation can provide quantifiably secure binary transmission between two entities, security being based on the nonclonability of photons. The objectives of the research are as follows: Show that interferometer-based coherence modulation...
Show moreSecure communication is a topic of great importance. The goal of our research reported here is to develop a scheme of secure communication system using coherence modulation at the photon counting level. When operated at the photon counting level, coherence modulation can provide quantifiably secure binary transmission between two entities, security being based on the nonclonability of photons. The objectives of the research are as follows: Show that interferometer-based coherence modulation can provide physics guaranteed secure binary transmission where each bit is associated with a countable number of photons. Review the operation of conventional high-light-level coherence modulation communication and then show, by means of example, that through the reduction of light intensities to photon-counting levels the system can be made secure. Analyze a particular attack on the system to demonstrate the quantifiability of the scheme’s security. Implement a version of the BB84 quantum key distribution protocol by slightly modifying our scheme in order to achieve a greater security. Identify a variety of issues related to hardware and the challenges of implementing our scheme in the real world.
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Date Issued
2017
PURL
http://purl.flvc.org/fau/fd/FA00004809, http://purl.flvc.org/fau/fd/FA00004809
Subject Headings
Photonics., Statistical communication theory., Optical data processing., Nanotechnology--Technological innovations., Quantum communication.
Format
Document (PDF)
Imaging through ground-level turbulence by fourier telescopy: simulations and preliminary experiments
Title
Imaging through ground-level turbulence by fourier telescopy: simulations and preliminary experiments.
Creator
Randunu-Pathirannehelage, Nishantha, Rhodes, William T., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Fourier telescopy imaging is a recently-developed imaging method that relies on active structured-light illumination of the object. Reflected/scattered light is measured by a large “light bucket” detector; processing of the detected signal yields the magnitude and phase of spatial frequency components of the object reflectance or transmittance function. An inverse Fourier transform results in the image. In 2012 a novel method, known as time-average Fourier telescopy (TAFT), was introduced by...
Show moreFourier telescopy imaging is a recently-developed imaging method that relies on active structured-light illumination of the object. Reflected/scattered light is measured by a large “light bucket” detector; processing of the detected signal yields the magnitude and phase of spatial frequency components of the object reflectance or transmittance function. An inverse Fourier transform results in the image. In 2012 a novel method, known as time-average Fourier telescopy (TAFT), was introduced by William T. Rhodes as a means for diffraction-limited imaging through ground-level atmospheric turbulence. This method, which can be applied to long horizontal-path terrestrial imaging, addresses a need that is not solved by the adaptive optics methods being used in astronomical imaging. Field-experiment verification of the TAFT concept requires instrumentation that is not available at Florida Atlantic University. The objective of this doctoral research program is thus to demonstrate, in the absence of full-scale experimentation, the feasibility of time-average Fourier telescopy through (a) the design, construction, and testing of smallscale laboratory instrumentation capable of exploring basic Fourier telescopy datagathering operations, and (b) the development of MATLAB-based software capable of demonstrating the effect of kilometer-scale passage of laser beams through ground-level turbulence in a numerical simulation of TAFT.
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Date Issued
2015
PURL
http://purl.flvc.org/fau/fd/FA00004401, http://purl.flvc.org/fau/fd/FA00004401
Subject Headings
Fourier analysis, Fourier integral operators, Interconnects (Integrated circuit technology), Remote sensing, Spread spectrum communications, Wireless sensor networks
Format
Document (PDF)
Transmitter-receiver system for time average fourier telescopy
Title
Transmitter-receiver system for time average fourier telescopy.
Creator
Pava, Diego F., Rhodes, William T., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Time Average Fourier Telescopy (TAFT) has been proposed as a means for obtaining high-resolution, diffraction-limited images over large distances through ground-level horizontal-path atmospheric turbulence. Image data is collected in the spatial-frequency, or Fourier, domain by means of Fourier Telescopy; an inverse two dimensional Fourier transform yields the actual image. TAFT requires active illumination of the distant object by moving interference fringe patterns. Light reflected from the...
Show moreTime Average Fourier Telescopy (TAFT) has been proposed as a means for obtaining high-resolution, diffraction-limited images over large distances through ground-level horizontal-path atmospheric turbulence. Image data is collected in the spatial-frequency, or Fourier, domain by means of Fourier Telescopy; an inverse two dimensional Fourier transform yields the actual image. TAFT requires active illumination of the distant object by moving interference fringe patterns. Light reflected from the object is collected by a “light-bucket” detector, and the resulting electrical signal is digitized and subjected to a series of signal processing operations, including an all-critical averaging of the amplitude and phase of a number of narrow-band signals.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00004314
Subject Headings
Digital communications, Fourier analysis, Fourier integral operators, Interconnects (Integrated circuit technology), Radio -- Transmitter receivers -- Design and construction, Spread spectrum communications, Wireless sensor networks
Format
Document (PDF)