Radiation of an array in a multimode waveguide with smoothly varying parameters

OLR (1986)33 (3)

A. PhysicalOceanography

A240. Optical properties 86:1454 Arst, Helgi, Kalju F.arme and hare Purga, 1984. On

the brightness coeffident of the Baltic Sea. Dt. hydrogr. Z., 37(6):221-233. Inst. of Thermophys. and Electrophys., Acad. of Sci. of the Estonian SSR, Paldiski st. 1, Tallinn 200031, USSR. 86:1455 Siegel, Herbert and Torsten Seifert, 1985. Influence of the sea bottom on the spectral reflectance in the Oder Bank region [Baltic Sea I. Beitr. Meeresk., 52:65-71. Bottom reflection is noticeable up to the surface between 450 nm and 650 nm at the most shallow station (8 m depth). In the region of maximum remission, near 560 nm, the remission coefficient of shallow waters is higher by a factor of two than of a 15 m water colunm for which bottom effects are negligible in the Baltic Sea. Akad. der Wissenschaften, Inst. fur Meeresk., DDR-2530 RostockWarnemunde, Seestr. 15, DRG.

A250. Electromagnetic properties 86:1456 Blanchard, D.C., 1985. Flow of electrical current from World Ocean to atmosphere. J. geophys. Res., 90(C5):9147-9148. The positively charged drops from bubbles bursting at the surface of the sea produce a flow of current from ocean to atmosphere. The charge flux has been measured to be about 4 × 10-tl C m -2 s-~. Multiplying this by the latest estimates of the area convered by whitecaps on the World Ocean between 70°N and 70°S gives a maximum current of 130 A. Atmos. Sci. Res. Center, SUNY, Albany, NY, USA.

A260. Acoustics

211

for estimating ray angle. In general, ocean maps degrade when the tracking data are withheld. However, when many high-precision ray travel time measurements are available, the degradation is small; in these cases it would be possible to deploy free-drifting instruments as part of a monitoring experiment. Inst. of Geophys. and Planet. Phys., Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA. 86:1458 Galkin, O.P. and V.M. Frolov, 1985. Fluctuations of the arrival angle of a sound signal reflected from the ocean surf~e. Sov. Phys. Acoust. (a translation of Akust. Zh.), 31(2):98-99. N.N. Andreev Acoustics Inst., Acad. of Sci., USSR. 86:1459 Godin, O.A. and I.V. Prokopyuk, 1985. Theory of the displacement of bounded wave beams In refleclion. Sov. Phys. Acoust. (a translation of Akust. Zh.), 31(2):103-107. P.P. Shirshov Inst. of Oceanol., Acad. of Sci., USSR. 86:1460 Gorskaya, N.S. and M.A. Raevskii, 1985. Acoustic mode ¢unverslun on a rough surface. Soy. Phys. Acoust. (a translation of Akust. Zh.), 31(2):107111. Inst. of Appl. Phys., Acad. of Sci., USSR. 86:1461 Kandelaki, D.V., 1985. Correlation characteristics of a modulated field in a randomly inbomoganeons medium. Soy. Phys. Acoust. (a translation of Akust. Zh.), 31(2):117-119. 86:1462 Kravtsov, Y.A. and V.M. Kuz'kin, 1985. Radiation of an array in a multtmode waveg~le with smoothly varying parameters. Soy. Phys. Acoust. (a translation of Akust. Zh.), 31(2): 119-122. Inst. of Gen. Phys., Acad. of Sci., USSR. 86:1463 Moose, R.L. and T.E. Dailey, 1985. Adaptive

underwater target tracking using passive multi-

86:1457 Cornuelle, B.D., 1985. Simulations of acoustic tomography array performance with untracked or drifting sources and receivers. J. geophys. Res, 90(C5):9079-9088.

path time-delay mensuremeuts. IEEE Trans. Acoust. Speech Signal Process~ ASSP-33(4):777-

It is possible to process tomographic travel times to estimate both ocean sound speed perturbations and mooring offsets, effecting a separation without external tracking. A side effect of this processing is a check on the ray identification since the varying instrument positions can be used as a synthetic array

86:1464 Reed, F.A., P.L. Feintuch and C.L. Weber, 1985. The LMS cancellation of narrow, extended

787. Dept. of Elect. Engrg., Virginia Polytech. Inst., Blacksburg, VA 24061, USA.

inlerferemees in sonar. IEEE Trans. Acoust. Speech Signal Process., ASSP-33(4):788-805. Hughes Aircraft Co., Fullerton, CA 92634, USA.