Nonlinear Detection, Estimation, and Control for Free-Space Optical Communication

Abstract

In free-space optical communication, the intensity of a laser beam is modulated by a message, the beam propagates through free-space or atmosphere, and eventually strikes the receiver. At the receiver, an optical sensor converts the optical energy into an electrical signal, which is processed to reconstruct the original message. The promising features of this communication scheme such as high-bandwidth, power efficiency, and security, render it a viable means for high data rate point-to-point communication. In this dissertation, we adopt a stochastic approach to address two major issues associated with free-space optics: digital communication over an atmospheric channel and maintaining optical alignment between the transmitter and the receiver, in spite of their relative motion. Associated with these issues, we consider several detection, estimation, and optimal control problems with point process observations. Although these problems are motivated by applications in free-space optics, they are also of direct relevance to the general field of estimation theory and stochastic control. We study the detection aspect of digital communication over an atmospheric channel. This problem is formulated as an M-ary hypothesis testing problem involving a doubly stochastic marked and filtered Poisson process in white Gaussian noise. The formal solutions we obtain for this problem are hard to express in an explicit form, thus we approximate them by appropriate closed form expressions. These approximations can be implemented using finite-dimensional, nonlinear, causal filters.

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Document Details

Document Type
Technical Report
Publication Date
Aug 17, 2008
Accession Number
ADA500103

Entities

People

  • Arash Komaee

Organizations

  • University of Maryland

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Space

DTIC Thesaurus Topics

  • Atmospheric Motion
  • Charge Carriers
  • Computational Science
  • Computer Simulations
  • Detection
  • Detectors
  • Differential Equations
  • Mathematical Filters
  • Mathematical Models
  • Military Research
  • Nonlinear Dynamics
  • Optical Detection
  • Optical Detectors
  • Partial Differential Equations
  • Random Variables
  • Stochastic Processes
  • Two Dimensional

Readers

  • Optical Fiber Sensing and Electromagnetic Propagation.
  • Radio communications and signal processing.
  • Systems Analysis and Design

Technology Areas

  • Directed Energy
  • Space
  • Space - Space Objects