Active high resolution time delay estimation for large BT signals

Two different high-resolution time-delay estimation (HRTDE) methods, a temporal method and a frequency method, specially adapted to large bandwidth duration (BT) product time-resolvent signals, are described. The performance gain of these methods is shown to be about four times better in comparison with the classical time-delay resolution methods. The frequency HRTDE method is applied to real data obtained from an ocean acoustic experiment. Although classic methods cannot distinguish close signal components, the method presented yields estimates of the delay differences and the attenuation associated with each propagation path