Be. Mcdonald et al., COMPARISON OF DATA AND MODEL PREDICTIONS FOR HEARD ISLAND ACOUSTIC TRANSMISSIONS, The Journal of the Acoustical Society of America, 96(4), 1994, pp. 2357-2370
Propagation paths and signal characteristics from the Heard Island Fea
sibility Test are modeled using a combination of adiabatic mode theory
, coupled mode theory, and parabolic equation (PE) methods. Adiabatic
mode theory predicts the horizontal propagation paths (including small
grazing angle reflections from bathymetry), group travel times, and e
stimates of signal loss due to bottom interaction. The PE calculations
are performed primarily to illustrate modal coupling near sharp ocean
ic fronts and bathymetry intruding into the sound channel. They are ca
rried out in depth and range along selected horizontal ray paths. For
the Heard Island to Christmas Island path, we carry out a time domain
pulse transmission using coupled mode equations. The result gives a pu
lse envelope in approximate agreement with observations.