MIT Libraries logoDSpace@MIT

MIT
View Item 
  • DSpace@MIT Home
  • MIT Libraries
  • MIT Theses
  • Graduate Theses
  • View Item
  • DSpace@MIT Home
  • MIT Libraries
  • MIT Theses
  • Graduate Theses
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Inertially stabilized platforms for SATCOM on-the-move applications : a hybrid open/closed-loop antenna pointing strategy

Author(s)
Marsh, Eric Allen
Thumbnail
DownloadFull printable version (17.60Mb)
Other Contributors
Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics.
Advisor
Dan Asta, Timothy Gallagher and Jonathan P. How.
Terms of use
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582
Metadata
Show full item record
Abstract
The increasing need for timely information in any environment has led to the development of mobile SATCOM terminals. SATCOM terminals seeking to achieve high data-rate communications require inertial antenna pointing to within fractions of a degree. The base motion of the antenna platform complicates the pointing problem and must be accounted for in mobile SATCOM applications. Antenna Positioner Systems (APSs) provide Inertially Stabilized Platforms (ISPs) for accurate antenna pointing and may operate in either an open or closed-loop fashion. Closed-loop antenna pointing strategies provide greater inertial pointing accuracies but typically come at the expense of more complex and costly systems. This thesis defines a nominal two-axis APS used on an EHF SATCOM terminal on a 707 aircraft. The nominal APS seeks to accomplish mobile SATCOM using the simplest possible system; therefore, the system incorporates no hardware specific to closed-loop pointing. This thesis demonstrates that the nominal APS may achieve accurate antenna pointing for an airborne SATCOM application using a hybrid open/closed-loop pointing strategy. The nominal APS implements the hybrid pointing strategy by employing an open-loop pedestal feedback controller in conjunction with a step-tracking procedure. The open-loop feedback controller is developed using optimal control techniques, and the pointing performance of the controller with the nominal APS is determined through simulation. This thesis develops closed-loop step-tracking algorithms to compensate for open-loop pointing errors.
 
(cont.) The pointing performance of several step-tracking algorithms is examined in both spatial pull-in and tracking simulations in order to determine the feasibility of employing hybrid pointing strategies on mobile SATCOM terminals. Keywords: Mobile SATCOM, Antenna Pointing, Inertially Stabilized Platform, Two-axis Positioner, Linear Quadratic Gaussian Control, Nonlinear Optimization.
 
Description
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2008.
 
Includes bibliographical references (p. 213-216).
 
Date issued
2008
URI
http://hdl.handle.net/1721.1/45259
Department
Massachusetts Institute of Technology. Department of Aeronautics and Astronautics
Publisher
Massachusetts Institute of Technology
Keywords
Aeronautics and Astronautics.

Collections
  • Graduate Theses

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

Login

Statistics

OA StatisticsStatistics by CountryStatistics by Department
MIT Libraries
PrivacyPermissionsAccessibilityContact us
MIT
Content created by the MIT Libraries, CC BY-NC unless otherwise noted. Notify us about copyright concerns.