|Title||The relation between the waveguide invariant and array invariant|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Song HC, Cho C|
|Journal||The Journal of the Acoustical Society of America|
|Keywords||acoustic arrays; acoustic wave interference; acoustic waveguides|
The waveguide invariant ββ is based on the dependence of group speed on phase speed and summarizes the robust interference phenomenon in the range-frequency plane. Over the last decade the elegant approach has been utilized for various applications including passive source ranging. Separately, the array invariant approach [Lee and Makris, J. Acoust. Soc. Am. 119, 336–351 (2006)] has been proposed for a robust source-range estimator from beam-time intensity data using either a horizontal or vertical array. In this paper, it is shown that the array invariant can be derived from the waveguide invariant theory assuming β=1β=1 .