AN EXPANDED CHARACTERIZATION OF THE INFORMATION CAPACITY OF A SHORT RANGE UNDERWATER COMMUNICATIONS CHANNEL.

The report considers theoretical limits in transmitting information through an underwater communications channel. Acoustic energy is the vehicle for information transfer since virtually no other form of energy propagates usefully in sea water. Short range near surface transmissions between computer...

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Bibliographic Details
Main Author: Kelley,Robert Lee
Other Authors: GEORGE WASHINGTON UNIV WASHINGTON D C SCHOOL OF ENGINEERING AND APPLIED SCIENCE
Format: Text
Language:English
Published: 1970
Subjects:
Cybernetics
Acoustics
Non-radio Communications
(*UNDERWATER COMMUNICATION SYSTEMS
*INFORMATION THEORY)
(*SOUND TRANSMISSION
UNDERWATER SOUND)
TRANSDUCERS
TRANSMITTER RECEIVERS
WHITE NOISE
GAIN
ATTENUATION
DETECTION
INTEGRAL EQUATIONS
STATISTICAL FUNCTIONS
TRANSFER FUNCTIONS
POWER SPECTRA
PROBABILITY
DISTRIBUTION FUNCTIONS
THESES
FILTERING THEORY
GAUSSIAN NOISE
*INFORMATION CAPACITY
North Atlantic
Online Access:http://www.dtic.mil/docs/citations/AD0713146
http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0713146
Description
Summary:The report considers theoretical limits in transmitting information through an underwater communications channel. Acoustic energy is the vehicle for information transfer since virtually no other form of energy propagates usefully in sea water. Short range near surface transmissions between computer bearing ocean vessels in the mid North Atlantic are evaluated. The characterization conducted provides valuable guidance needed for designing optimum signal generation and detection systems. The fundamental mechanism involved in undersea transmissions is analyzed to develop a channel model. Major channel characteristics are high energy absorption and the severe time varying multipath environment. It is shown that directive transmitting and receiving transducers mitigate the multipath problems and allow a frequency dispersive, time selective model to be employed. (Author)

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