ASA 128th Meeting - Austin, Texas - 1994 Nov 28 .. Dec 02

1pUW10. Stability of signal plus noise in performance evaluation of processing schemes.

Jacob George

Ronald A. Wagstaff

Naval Res. Lab., Code 7176, Stennis Space Center, MS 39529

The stability of signal plus noise and the mechanisms governing the combination of signal and noise at the receiver are reported. These questions become important in performance evaluation of processing schemes which are designed to enhance the S/N ratio. Of special interest is the case of a weak signal combining with a relatively stronger noise. Even though the nonlinear interaction of sound by sound continues to be a hot topic [see, for example, P. J. Westervelt, ``Answer to criticism of experiment on scattering of sound by sound,'' J. Acoust. Soc. Am. 95, 2865 (1994)], the largely linear effects governed by the superposition principle are of primary importance in the present application. Simple rules governing the combination of signal and noise, obtained through analysis of experimental data and model calculations, will be discussed. [Work supported by ONR, with technical management provided by NRL/SSC.]