complex problems associated with passage 

 through dangerous and restricted waters, and 

 evaluate the relationships between the watch 



officer, the ship dynamics, the wheelhouse and 

 equipment, and the sea environment. 



OFFICE OF TELECOMMUNICATIONS 



The research and engineering arm of the Office 

 of Telecommunications is known as the Institute 

 for Telecommunication Sciences (ITS) and is lo- 

 cated in Boulder, Colorado. The role of the Office 

 of Telecommunications is to provide specialized 

 research and analysis essential for increasing suc- 

 cessful applications of telecommunications tech- 

 nology. In turn, the goals of the ITS are to: 



• Increase the availability of usable spectrum 

 by engineering methods. 



• Increase the likelihood of satisfactory tele- 

 communication system performance, as af- 

 fected by natural, engineering, and economic 

 factors. 



ITS's contributions are made through three broad 

 programs: (1) Efficient use of the spectrum. (2) 

 engineering and evaluation of systems, and (3) 

 electromagnetic wave transmission research and 

 services. 



These three prtigrams are highly dependent 

 upon one another. For example, transmission 

 phenomena play an important role in determining 

 whether radio systems will work in the field, as do 

 questions of mutual interference between systems 

 or subsystems. Variability of transmission loss 

 through the atmosphere determines the physical 

 separation between systems sharing the same fre- 

 quency and thus affects the efficiency of spectrum 

 use. Engineering of systems to obtain the required 

 performance demands adequate knowledge of 



transmission loss and distortion, as well as the 

 effects of interference. 



Basic research in ITS represents a small portion 

 of the total etTort and is that long-term discipli- 

 nary research that underpins the engineering ef- 

 fort. It is found primarily within the wave trans- 

 mission area. Most of ITS's work is in applied 

 research. 



In electromagnetic wave transmission research, 

 the basic research effort is aimed at improving the 

 successful deployment of radio systems designed 

 to operate near the state of the art, insofar as 

 propagation is concerned. Deleterious propagation 

 effects form a basic limitation to the performance 

 of radio systems. Attenuation, scattering, ducting, 

 and refraction affect both wanted and unwanted 

 signals. Scattering the multipath may limit the 

 available band width. 



Recent work of a long-term character of particu- 

 lar interest includes: 



• Studies of the strength and width of the Ot 

 microwave spectra in relation to the attenua- 

 tion of microwave signals. 



• Studies of the effects of rain on terrestrial and 

 satellite microwave paths, and development 

 of predictive techniques. 



• Development of improved models for pre- 

 dicting multihop high frequency. 



COMMERCE 



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