Equivalence of adaptive time reversal and least squares for cross talk mitigation

Abstract

A recent paper [H. C. Song et al., J. Acoust. Soc. Am. 127, EL19–EL22 (2010)] demonstrated adaptive time reversal (ATR) using at-sea experimental data which significantly suppressed the cross talk among users (or transmitters) over conventional time reversal. In this letter, the ATR approach is shown essentially equivalent to the least squares solution to an over-determined system.