Time Smear and Frequency Smear Studies of the BIFI Range.
Abstract
The BIFI range is a shallow water acoustic range in Long Island Sound, about 19 miles long and 120 feet deep. Results of time smear and frequency smear studies made on this range are presented. It is shown how these results may be used to predict signal fluctuation. In time smear studies, the received signal is divided into a front, main arrival and tail. The relative energies of the three sections of the signal are computed and these results are used to predict the range of signal fluctuations. The above analysis and computation are easily carried out on a digital computer using as input data automatically punched on IBM cards. Frequency smear is the doppler shift undergone by a signal as a result of being reflected from a moving surface. Many frequnecy smear spectra were obtained for varying sea states, and from these, dispersion as a function of sea state was calculated. The dispersion increased with sea state, in agreement with theory. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 20, 1970
- Accession Number
- ADA033133
Entities
People
- Bernard Sussman
- William G. Kanabis
Organizations
- Navy Underwater Sound Laboratory