Author: Daniel E. Frye
Publisher:
ISBN:
Category : Oceanographic buoys
Languages : en
Pages : 710
Book Description
A system concept has been developed by Viasat, Inc. and Woods Hole Oceanographic Institution for improving the data telemetry bandwidth available on ocean buoys. This concept utilizes existing communications satellites as data relay stations and mechanically steered antenna arrays to achieve increased data rates and improved power efficiency needed for ocean applications. This report describes an initial feasibility and design study to determine if a mechanically steered antenna array can meet the requirements of open ocean buoy applications. To meet the system requirements, an 18-element microstrip antenna (9-element transmit, 9-element receive) was designed and fabricated under subcontract by Seavey Engineering Associates, Inc. It operates in the 4-6 GHz frequency band (C-band) and provides 14 dB of gain. The % power beamwidth is j150 in azimuth and elevation. This antenna design, in conjunction with a simple rotating mount, was used to evaluate the potential of this approach to keep a geostationary satellite in view when mounted on an ocean buoy. The evaluation is based on laboratory measurements using a magnetic compass and a small stepper motor to maintain antenna orientation while the complete assembly was rotated and tilted at speeds similar to what would be expected on an offshore buoy equipped with a stabilizing wind vane.
Design and Evaluation of a Directional Antenna for Ocean Buoys
Author: Daniel E. Frye
Publisher:
ISBN:
Category : Oceanographic buoys
Languages : en
Pages : 710
Book Description
A system concept has been developed by Viasat, Inc. and Woods Hole Oceanographic Institution for improving the data telemetry bandwidth available on ocean buoys. This concept utilizes existing communications satellites as data relay stations and mechanically steered antenna arrays to achieve increased data rates and improved power efficiency needed for ocean applications. This report describes an initial feasibility and design study to determine if a mechanically steered antenna array can meet the requirements of open ocean buoy applications. To meet the system requirements, an 18-element microstrip antenna (9-element transmit, 9-element receive) was designed and fabricated under subcontract by Seavey Engineering Associates, Inc. It operates in the 4-6 GHz frequency band (C-band) and provides 14 dB of gain. The % power beamwidth is j150 in azimuth and elevation. This antenna design, in conjunction with a simple rotating mount, was used to evaluate the potential of this approach to keep a geostationary satellite in view when mounted on an ocean buoy. The evaluation is based on laboratory measurements using a magnetic compass and a small stepper motor to maintain antenna orientation while the complete assembly was rotated and tilted at speeds similar to what would be expected on an offshore buoy equipped with a stabilizing wind vane.
Publisher:
ISBN:
Category : Oceanographic buoys
Languages : en
Pages : 710
Book Description
A system concept has been developed by Viasat, Inc. and Woods Hole Oceanographic Institution for improving the data telemetry bandwidth available on ocean buoys. This concept utilizes existing communications satellites as data relay stations and mechanically steered antenna arrays to achieve increased data rates and improved power efficiency needed for ocean applications. This report describes an initial feasibility and design study to determine if a mechanically steered antenna array can meet the requirements of open ocean buoy applications. To meet the system requirements, an 18-element microstrip antenna (9-element transmit, 9-element receive) was designed and fabricated under subcontract by Seavey Engineering Associates, Inc. It operates in the 4-6 GHz frequency band (C-band) and provides 14 dB of gain. The % power beamwidth is j150 in azimuth and elevation. This antenna design, in conjunction with a simple rotating mount, was used to evaluate the potential of this approach to keep a geostationary satellite in view when mounted on an ocean buoy. The evaluation is based on laboratory measurements using a magnetic compass and a small stepper motor to maintain antenna orientation while the complete assembly was rotated and tilted at speeds similar to what would be expected on an offshore buoy equipped with a stabilizing wind vane.
Design and Evaluation of a Directional Antenna for Ocean Buoys
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Funding was provided by Viasat, Inc., under subcontract No. SC95001 and by a Cecil H. and Ida M. Green Technology Innovation Award.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Funding was provided by Viasat, Inc., under subcontract No. SC95001 and by a Cecil H. and Ida M. Green Technology Innovation Award.
Evaluation, Comparison and Calibration of Oceanographic Instruments
Author: Society for Underwater Technology (SUT)
Publisher: Springer Science & Business Media
ISBN: 9780860106692
Category : Science
Languages : en
Pages : 286
Book Description
Publisher: Springer Science & Business Media
ISBN: 9780860106692
Category : Science
Languages : en
Pages : 286
Book Description
Water Spectrum
Author:
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 232
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 232
Book Description
International Ocean Systems Design
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Maritime Information Review
Design of a Mobile Coastal Communications Buoy
Author: Meghan Hendry-Brogan
Publisher:
ISBN:
Category : Oceanographic buoys
Languages : en
Pages : 86
Book Description
(Cont.) The NEC buoy displaces approximately 140 kg of sea water and is roughly 11 feet long when fully assembled, not including its 5 foot antenna mast. The buoy employs a PC104 stack to control an 802.1 lb wireless card and antenna, an acoustic modem card and transducer, other peripheral instrumentation, a main battery, and a solar power system.
Publisher:
ISBN:
Category : Oceanographic buoys
Languages : en
Pages : 86
Book Description
(Cont.) The NEC buoy displaces approximately 140 kg of sea water and is roughly 11 feet long when fully assembled, not including its 5 foot antenna mast. The buoy employs a PC104 stack to control an 802.1 lb wireless card and antenna, an acoustic modem card and transducer, other peripheral instrumentation, a main battery, and a solar power system.
Antennas
Author: Boris Levin
Publisher: CRC Press
ISBN: 1000220052
Category : Technology & Engineering
Languages : en
Pages : 421
Book Description
The book comprises a new method of solving the integral equation of Leontovich, the most rigorous and most effective equation for the current in thin linear antennas. The book describes the features of the new method in its application in various types of antennas. It considers new ways of analyzing antennas, in particular in the calculation of an antenna gain based on main radiation patterns and the calculation of the directional characteristics of radiators with known distribution of current amplitude. The method of electrostatic analogy proposed by the author, provides the base for comparison of electromagnetic fields of high-frequency currents and electrostatic charges located on linear conductors to improve the directional characteristics of log-periodic and director-type antennas. A new approach to the analysis of the electrical characteristics of a microstrip antenna, which allows expansion of its operation range, is substantiated and developed. New results of antenna synthesis are obtained. The second part of the book is devoted to specific types of antennas (the author had a significant role in their creation). Particular attention is given to ship antennas for different frequency ranges. The book is intended for professionals, working in electrodynamics and those working on development, placement and exploitation of antennas. It will be useful for lecturers (university-level professors), teachers, students of radio engineering and researchers working in various fields of radio electronics and interested in an in-depth study of theoretical problems and designs f antennas. It can also be used for short university courses.
Publisher: CRC Press
ISBN: 1000220052
Category : Technology & Engineering
Languages : en
Pages : 421
Book Description
The book comprises a new method of solving the integral equation of Leontovich, the most rigorous and most effective equation for the current in thin linear antennas. The book describes the features of the new method in its application in various types of antennas. It considers new ways of analyzing antennas, in particular in the calculation of an antenna gain based on main radiation patterns and the calculation of the directional characteristics of radiators with known distribution of current amplitude. The method of electrostatic analogy proposed by the author, provides the base for comparison of electromagnetic fields of high-frequency currents and electrostatic charges located on linear conductors to improve the directional characteristics of log-periodic and director-type antennas. A new approach to the analysis of the electrical characteristics of a microstrip antenna, which allows expansion of its operation range, is substantiated and developed. New results of antenna synthesis are obtained. The second part of the book is devoted to specific types of antennas (the author had a significant role in their creation). Particular attention is given to ship antennas for different frequency ranges. The book is intended for professionals, working in electrodynamics and those working on development, placement and exploitation of antennas. It will be useful for lecturers (university-level professors), teachers, students of radio engineering and researchers working in various fields of radio electronics and interested in an in-depth study of theoretical problems and designs f antennas. It can also be used for short university courses.
The Federal Plan for Meteorological Services and Supporting Research
Author: United States. Office of Federal Coordinator for Meteorological Services and Supporting Research
Publisher:
ISBN:
Category : Meteorology
Languages : en
Pages : 68
Book Description
Publisher:
ISBN:
Category : Meteorology
Languages : en
Pages : 68
Book Description